Active toe angle adjustment of a wheel of an electric vehicle

The invention pertains to a method for active toe angle adjustment of a wheel of an electric vehicle, an active toe angle adjustment system, an electric vehicle comprising an active toe angle adjustment system and computer program for carrying out instructions pertaining to active toe angle adjustment of a wheel of an electric vehicle.

The toe angle is the angle in a horizontal plane at which a wheel of a vehicle is arranged relative to the horizontal longitudinal axis of that vehicle when the vehicle is driving in a straight line (i.e. when the vehicle does not turn a corner). The toe angle relates to the angle of rotation of the wheel around a vertical rotation axis.

The angle in a horizontal plane between the left front wheel and the right front wheel is referred to as the combined front toe angle. The angle in a horizontal plane between the left rear wheel and the right rear wheel is referred to as the combined rear toe angle. The combined toe angle pertains to a combination of a wheel on the left side of the vehicle and a wheel on the right side of the vehicle, wherein both wheels of the combination have the same position as seen in the longitudinal direction, so e.g. both are front wheels or both are rear wheels.

If the wheels of a combination of wheels are arranged such that at the front of the wheels (as seen in the forward driving direction of the vehicle) the wheels are closer together than at the rear of the same wheels, this is called “toe-in”. If the wheels of a combination of wheels are arranged such that at the rear of the wheels (as seen in the forward driving direction of the vehicle) the wheels are closer together than at the front of the same wheels, this is called “toe-out”.

In general, if the right front wheel has a toe angle of x°, the left front wheel has a toe angle of -x°, and likewise, if the right rear wheel has a toe angle of y°, the left rear wheel has a toe angle of -y°. However, in some situations deviations from this general rule are possible, although such deviations may require a steering correction. If the right front wheel has a toe angle of x° and the left front wheel has a toe angle of -x°, the combined front toe angle is 2x°. If the right rear wheel has a toe angle of y° and the left rear wheel has a toe angle of -y°, the combined rear toe angle is 2y°.

The toe angle (and therewith also the combined toe angle) has an influence on the driving properties of the vehicle, for example on the straight-line stability, turning response, and stability during cornering, and for example on tire wear. Normally, the toe angle of a vehicle is set in the factory, and sometimes after maintenance or changes of wheels and/or tires. Active toe angle adjustment is also known, for example setting the toe angle to a predetermined value when the vehicle is switched to front wheel drive and setting a different predetermined toe angle when the vehicle is switched to four wheel drive. Active toe angle adjustment is known for vehicles that are designed to be able to deal with a variety of driving terrain, and for high performance vehicles such as race cars or rally cars.

EP1958841 discloses an embodiment in which the toe angle of the rear wheels is changed intentionally during driving. During a time interval of e.g. 3 minutes, the real time fuel consumption of the combustion engine is measured and the fuel consumption is calculated.

A disadvantage of the disclosure of D1 is that in a vehicle which is driven by a combustion engine, it takes time to monitor the fuel consumption in order to determine the fuel consumption, e.g. due to inertia-effects in the fuel system. This means that in a practical implementation, the relation between toe angle and fuel consumption is determined only once in a while, the results are stored in a database and then re-used during a later period of time, also when for example the road conditions or weather conditions are different.

It is an object of the invention to improve the energy efficiency of an electric vehicle.

In a first aspect of the invention, this object is achieved by a method for active toe angle adjustment of a wheel of an electric vehicle, which method comprises the following steps:

- during driving, with a first wheel of the electric vehicle being arranged at a first toe angle, generating a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the first toe angle,

- during driving, changing the toe angle of the first wheel to a second toe angle which is different from the first toe angle, and while the first wheel is at the second toe angle, generating a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle,

- determining which toe angle is associated with the lowest electric propulsion power consumption,

- arranging the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption.

In the method according to the first aspect of the invention, a first power consumption data set is generated which is indicative for real time electric propulsion power consumption when the first wheel is at the first toe angle. The first power consumption data set is generated during driving of the vehicle. The first wheel is at the first toe angle when the first power consumption data set is generated.

The first wheel is for example a front wheel or a rear wheel. The electric vehicle is for example a front wheel driven vehicle, a rear wheel driven vehicle, a four wheel driven vehicle or an all wheel driven vehicle. The electric vehicle may be powered by a central electric motor that supplies electrical propulsion power to all driven wheels of the vehicle. Alternatively or in addition, the electric vehicle may comprise an in-wheel electric motor for at least one driven wheel, optionally for all driven wheels. A hybrid vehicle is in the context of the invention also considered to be an electric vehicle when it runs in full electric mode. The electric vehicle optionally is a high efficiency electric vehicle. The electric vehicle is optionally a solar vehicle, i.e. an electric vehicle which is at least partly chargeable by means of solar cells which are integrated in the vehicle. Typically, such a solar vehicle comprises at least one traction battery for supplying electrical power to the electric motor or motors, and vehicle integrated solar cells for charging the traction battery. Additional charging of the traction battery via for example an external electrical power grid (e.g. the main power grid) is also possible.

The electric vehicle is for example a car (e.g. a passenger car), a delivery vehicle, a recreational vehicle or a van.

The first power consumption data set comprises at least a datapoint relating to a measured or otherwise determined value of a parameter that is indicative for the consumed electric propulsion power at the time of generating the data set (’’real time”) and a datapoint pertaining to the value of the first toe angle. Electric propulsion power is the electric power that is used to propel the vehicle, e.g. the electric power to operate a central electric motor or one or more or all in-wheel motors of the electric vehicle.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set allows to establish or estimate how much electric power is consumed to propel the car. The parameter is for example measured instantaneously (i.e. at one discrete moment) or during a time period or over a certain distance travelled by the vehicle. Optionally, the first power consumption data set comprises one or more processed values, e.g. values calculated from measured data, such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set.

For example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined by measuring the amount of electric propulsion power that is required for keeping the vehicle at a constant velocity. Alternatively, for example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined by interrupting the supply of electric propulsion power to the vehicle, e.g. to the wheels of the vehicle, and determining the length of the time period that passes before the velocity of the vehicle is reduced by a certain amount or percentage (e.g. 2 km/h or 1%). Alternatively or in addition, for example the one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined during regenerative braking, e.g. by determining (e.g. measuring) the amount of power that is supplied to the battery by the regenerative braking system, optionally in combination with determining the reduction in velocity of the vehicle, e.g. during the time the power supply to the battery by the regenerative braking system is determined.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is for example electric power, an electric current, an electric voltage, a combination of an electric current and an electric voltage. Optionally, the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is not only indicative but also representative for the consumed electric propulsion power at the time of generating the data set.

Optionally, the first power consumption data set is stored in a computer memory, e.g. in a vehicle-specific database. The vehicle-specific database contains information about the specific, individual vehicle for which the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set has been generated.

The first power consumption data set is generated during driving, i.e. during normal operation of the vehicle, so that a vehicle-specific power consumption data set is generated. The value or values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set may depend on various driving condition parameters, e.g. velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. Optionally, parameter values indicative or representative for one or more of such driving condition parameters are also comprised in the first power consumption data set. The method may be initiated by the driver or by a vehicle control system.

In a further step of the method according to the first aspect of the invention, during driving the toe angle of the first wheel is changed to a second toe angle which is different from the first toe angle. While the first wheel is at the second toe angle, a second power consumption data set is generated which is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle. The difference between the first and the second toe angle is for example 0.1° - 1.5° (both mentioned values included), e.g. 0.25°- 1.0° (both mentioned values included), for example 0.5°.

The second power consumption data set comprises at least a datapoint relating to a measured or otherwise determined value of a parameter that is indicative for the consumed electric propulsion power at the time of generating the data set (’’real time”) and a datapoint pertaining to the value of the second toe angle.

The second power consumption data set optionally comprises at least parameter values of parameters that are comprised in the first data set so that comparison of data in the first power consumption data set and data in the second power consumption data set is possible.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set allows to establish or estimate how much electric power is consumed to propel the car. The parameter is for example measured instantaneously (i.e. at one discrete moment) or during a time period or during a predetermined distance travelled by the vehicle. Optionally, the second power consumption data set comprises one or more processed values, e.g. values calculated from measured data, such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the second power consumption data set.

For example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is determined by measuring the amount of electric propulsion power that is required for keeping the vehicle at a constant velocity or by interrupting the supply of electric propulsion power to the vehicle, e.g. to the wheels of the vehicle, and determining the length of the time period that passes before the velocity of the vehicle is reduced by a certain amount or percentage (e.g. 2 km/h or 1%). Alternatively or in addition, for example the one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined during regenerative braking, e.g. by determining (e.g. measuring) the amount of power that is supplied to the battery by the regenerative braking system, optionally in combination with determining the reduction in velocity of the vehicle, e.g. during the time the power supply to the battery by the regenerative braking system is determined.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is for example electric power, an electric current, an electric voltage, a combination of an electric current and an electric voltage. Optionally, the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is not only indicative but also representative for the consumed electric propulsion power at the time of generating the data set.

Optionally, the second power consumption data set is stored in a computer memory, e.g. in a vehicle-specific database. The vehicle-specific database contains information about the specific, individual vehicle for which the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set has been generated.

The second power consumption data set is generated during driving, i.e. during normal operation of the vehicle, so that a vehicle-specific power consumption data set is generated. The value or values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set may depend on various driving condition parameters, e.g. velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. Optionally, parameter values indicative or representative for one or more of such driving condition parameters are also comprised in the second power consumption data set. The method may be initiated by the driver or by a vehicle control system.

In a further step of the method according to the first aspect of the invention, it is determined which toe angle is associated with the lowest electric propulsion power consumption. This step is carried out based on the first and second power consumption data sets, e.g. on the full power consumption data sets or on processed values in these power consumption data sets, such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set. For example, the average power consumption of the first power consumption data set and the average of the second power consumption data set are compared with each other.

In practical cases, this step will be carried out during driving. However, alternatively it may be carried out at a stop, e.g. the next stop, of the vehicle.

The toe angle which is associated with the lowest electric propulsion power consumption can be for example be the first toe angle, the second toe angle or a toe angle that is different from the first and the second to angle. In the latter case, the toe angle that is associated with the lowest electric propulsion power consumption is determined by processing the first and second power consumption data set, e.g. based on further analysis of the power consumption datasets, which optionally includes a data analysis operation such as curve fitting. The toe angle which is associated with the lowest electric propulsion power consumption can be for example alternatively be determined on the basis of a straightforward comparison of the data in the first and second power consumption data sets.

In a further step of the method according to the first aspect of the invention, the first wheel of the electric vehicle is arranged at the toe angle that is associated with the lowest electric propulsion power consumption.

In practical cases, this step will be carried out during driving. However, alternatively it may be carried out at a stop, e.g. at the next stop, of the vehicle.

The toe angle of a wheel of an electric vehicle has an influence on the propulsion power consumption of the vehicle. The optimal toe angle in view of energy efficiency however depends on various driving condition parameters, such as velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. These driving conditions vary from vehicle to vehicle, from trip to trip and even during a trip.

The method according to the first aspect of the invention allows to optimize the energy efficiency of the electric vehicle, in particular with respect to the propulsion power consumption of the vehicle, under varying driving conditions and specifically for each individual vehicle, instead of having to rely on generally factory-determined settings, which will be sub-optimal in many practical driving conditions.

In an electric vehicle, the power consumption can be determined within a much shorter measurement time than in a vehicle that is driven by a combustion engine. In an electric vehicle, the power consumption can be determined very quickly, e.g. within seconds or even less than a second, while in a combustion engine powered vehicle this takes at least several minutes. The short measuring time makes it possible to determine the relation between toe angle and fuel consumption more often, e.g. during each trip or even several times during a single trip. This makes it easier to take driving conditions (such as the type of road, speed of the vehicle and/or weather conditions) into account, which makes the system more effective. In some embodiments, it may even remove the need for a database, resulting in a simpler, lighter and/or cheaper system.

Optionally, the method according to the invention is carried out by an active toe angle adjustment system in accordance with the first aspect of the invention, for example by an active toe angle adjustment system according to in the first invention in accordance with a described embodiment and/or a combination of described embodiments.

In an embodiment, the method according to the first aspect of the invention includes the step of, during driving, changing the toe angle of the first wheel to a further toe angle which is different from the first toe angle and from the second toe angle. Then, a further power consumption data set is generated which is indicative for real time electric propulsion power consumption when the first wheel is at the further toe angle.

In this embodiment, optionally this step is repeated for one or more additional mutually different further toe angles of the first wheel. Therewith, multiple further power consumption data sets are obtained, each further power consumption data set being associated with a single further toe angle.

The difference between a further toe angle and the first, the second toe angle or a different further toe angle is for example 0.1° - 1.5° (both mentioned values included), e.g. 0.25°- 1.0° (both mentioned values included), for example 0.5°.

This embodiment provides more than two power consumption data sets, which allows to more accurately determine the toe angle that is associated with the lowest electric propulsion power consumption.

The further power consumption data set comprises at least a datapoint relating to a measured or otherwise determined value of a parameter that is indicative for the consumed electric propulsion power at the time of generating the data set (’’real time”) and a datapoint pertaining to the value of the further toe angle.

The further power consumption data set optionally comprises at least parameter values of parameters that are comprised in the first data set so that comparison of data in the first power consumption data set and data in the further power consumption data set is possible.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set allows to establish or estimate how much electric power is consumed to propel the car. The parameter is for example measured instantaneously (i.e. at one discrete moment) or during a time period or during a predetermined distance travelled by the vehicle. Optionally, the further power consumption data set comprises one or more processed values, e.g. values calculated from measured data, such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the further power consumption data set.

For example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is determined by measuring the amount of electric propulsion power that is required for keeping the vehicle at a constant velocity, or by interrupting the supply of electric propulsion power to the vehicle, e.g. to the wheels of the vehicle, and determining the length of the time period that passes before the velocity of the vehicle is reduced by a certain amount or percentage (e.g. 2 km/h or 1%). Alternatively or in addition, for example the one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined during regenerative braking, e.g. by determining (e.g. measuring) the amount of power that is supplied to the battery by the regenerative braking system, optionally in combination with determining the reduction in velocity of the vehicle, e.g. during the time the power supply to the battery by the regenerative braking system is determined.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is for example electric power, an electric current, an electric voltage, a combination of an electric current and an electric voltage. Optionally, the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is not only indicative but also representative for the consumed electric propulsion power at the time of generating the data set.

Optionally, the further power consumption data set is stored in a computer memory, e.g. in a vehicle-specific database. The vehicle-specific database contains information about the specific, individual vehicle for which the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set has been generated.

The further power consumption data set is generated during driving, i.e. during normal operation of the vehicle, so that a vehicle-specific power consumption data set is generated. The value or values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set may depend on various driving condition parameters, e.g. velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. Optionally, parameter values indicative or representative for one or more of such driving condition parameters are also comprised in the further power consumption data set.

In an embodiment of the method according to the first aspect of the invention, the first toe angle of the first wheel is combined with a first additional toe angle of a second wheel when generating the first power consumption data set. In this embodiment, the second wheel is a front wheel when the first wheel is a front wheel and the second wheel is a rear wheel when the first wheel is a rear wheel. The first power consumption data set is in this embodiment indicative for real time electric propulsion power consumption when the first wheel is at the first toe angle and the second wheel is at the first additional toe angle.

Alternatively or in addition, in this embodiment, the second toe angle of the first wheel is combined with a second additional toe angle of a second wheel when generating the second power consumption data set. In this embodiment, the second wheel is a front wheel when the first wheel is a front wheel and the second wheel is a rear wheel when the first wheel is a rear wheel. The second power consumption data set is in this embodiment indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle and the second wheel is at the second additional toe angle.

Alternatively or in addition, in this embodiment, at least one further toe angle of the first wheel is combined with a further additional toe angle of a second wheel when generating the further power consumption data set. In this embodiment, the second wheel is a front wheel when the first wheel is a front wheel and the second wheel is a rear wheel when the first wheel is a rear wheel. The respective further power consumption data set is indicative for real time electric propulsion power consumption when the first wheel is at the at least one further toe angle and the second wheel is at the further additional toe angle.

In this embodiment, the toe angle of e.g. the left front wheel and the right front wheel, and/or the left rear wheel and the right rear wheel are considered in combination with each other when generating art least one, an optionally multiple or all, power consumption data set(s). This is likely to provide a more accurate outcome of the determination of the optimal setting of the toe angle and additional toe angle in order to obtain the lowest electric propulsion power consumption.

In this embodiment, optionally the second wheel is arranged at the additional toe angle that is associated with the lowest electric propulsion power consumption. So, in this case, the combination of the toe angle of the first wheel and additional toe angle of the second wheel that is associated with the lowest electric propulsion power consumption is determined, and the first wheel is arranged at the toe angle associated with this combination and the second wheel is arranged at the additional toe angle that is associated with this same combination. For example, the first wheel is arranged at the first toe angle and the second wheel is arranged at the first additional toe angle if it turns out that the combination of the first toe angle and the first additional toe angle is associated with the lowest electric propulsion power consumption, or the first wheel is arranged at the second toe angle and the second wheel is arranged at the second additional toe angle if it turns out that the combination of the second toe angle and the second additional toe angle is associated with the lowest electric propulsion power consumption, or the first wheel is arranged at a further toe angle and the second wheel is arranged at the further additional toe angle that is associated with this particular further toe angle if it turns out that the combination of the further toe angle and the associated further additional toe angle is associated with the lowest electric propulsion power consumption.

In this embodiment, optionally the first toe angle and the first additional toe angle have the same value but are opposite in direction. For example, the first toe angle is 0.5°and the first additional toe angle is -0.5°. Alternatively, optionally the first toe angle and the first additional toe angle do not have the same value but still are opposite in direction. For example, the first toe angle is 0.45°and the first additional toe angle is -0.55°. This may occur e.g. due to a different wear pattern in the left and right tire. In this case, additional steering corrections may be required.

Likewise, optionally the second toe angle and the second additional toe angle have the same value but are opposite in direction. For example, the second toe angle is 0.5°and the second additional toe angle is -0.5°. Alternatively, optionally the second toe angle and the second additional toe angle do not have the same value but still are opposite in direction. For example, the second toe angle is 0.45°and the second additional toe angle is -0.55°.

Likewise, optionally the further toe angle and the further additional toe angle have the same value but are opposite in direction. For example, the further toe angle is 0.5°and the further additional toe angle is -0.5°. Alternatively, optionally the further toe angle and the further additional toe angle do not have the same value but still are opposite in direction. For example, the further toe angle is 0.45°and the further additional toe angle is -0.55°.

In a variant of this embodiment, the first toe angle of the first wheel is combined with a first additional toe angle of a second wheel when generating the first power consumption data set, and the second toe angle of the first wheel is combined with a second additional toe angle of a second wheel when generating the second power consumption data set, and at least one further toe angle of the first wheel is combined with a further additional toe angle of a second wheel when generating the further power consumption data set. In this variant, optionally, the first toe angle is the same as the second toe angle, and the first additional toe angle is different from the second additional toe angle, and the further toe angle is different from the first toe angle and from the second toe angle, and the further additional toe angle is the same as either the first additional toe angle or the second additional toe angle. Alternatively, the first toe angle, second toe angle and further toe angle(s) are all different from each other and the first additional toe angle, second additional toe angle and further additional toe angle(s) are also all different from each other.

In an embodiment of the method according to the first aspect of the invention, the step of determining which toe angle is associated with the lowest electric propulsion power consumption includes comparing the first power consumption data set and the second power consumption data set with each other, and determining which power consumption data set indicates the lowest electric propulsion power consumption.

This is a straightforward way of determining which power consumption data set indicates the lowest electric propulsion power consumption, requiring little computer power and data processing power.

Optionally, in this embodiment, the first wheel is arranged into the first or the second toe angle after determination which of these toe angles is associated with the lowest electric propulsion power consumption.

In an embodiment, the method according to the first aspect of the invention includes the step of, during driving, changing the toe angle of the first wheel to a further toe angle which is different from the first toe angle and from the second toe angle. Then, a further power consumption data set is generated which is indicative for real time electric propulsion power consumption when the first wheel is at the further toe angle. Optionally this step is repeated for one or more additional mutually different further toe angles of the first wheel. Therewith, multiple further power consumption data sets are obtained, each further power consumption data set being associated with a single further toe angle. Furthermore, in this embodiment, the step of determining which toe angle is associated with the lowest electric propulsion power consumption includes comparing at least one further power consumption data set with at least one of the first power consumption data set and the second power consumption data set and determining which of the first, second and further power consumption data sets indicates the lowest electric propulsion power consumption.

For example, first the first power consumption data set and the second power consumption data set are compared with each other, and it is determined which of these two power consumption data sets is associated with the lowest electric propulsion power consumption, and then that power consumption data set is compared to the further power consumption data set.

This is a straightforward way of determining which power consumption data set indicates the lowest electric propulsion power consumption, requiring little computer power and data processing power.

Optionally, in this embodiment, the first wheel is arranged into the first or the second toe angle or the further toe angle after determination which of these toe angles is associated with the lowest electric propulsion power consumption.

In an embodiment, the method according to the first aspect of the invention includes the step of, during driving, changing the toe angle of the first wheel to a further toe angle which is different from the first toe angle and from the second toe angle. Then, a further power consumption data set is generated which is indicative for real time electric propulsion power consumption when the first wheel is at the further toe angle. Optionally this step is repeated for one or more additional mutually different further toe angles of the first wheel. Therewith, multiple further power consumption data sets are obtained, each further power consumption data set being associated with a single further toe angle. Furthermore, in this embodiment, the step of determining which toe angle is associated with the lowest electric propulsion power consumption includes determining a relation between the toe angle and the electric propulsion power consumption based on the generated power consumption data sets, e.g. through curve fitting, and selecting the toe angle that is associated with the lowest electric propulsion power consumption on the basis of this determined relation.

This embodiment may result in arranging the first wheel at a toe angle which is different from the first, second and further toe angle, in case the determined relation between the toe angle and the electric propulsion power consumption shows that e.g. an intermediate toe angle provides a lower electric propulsion power consumption.

This embodiment allows to further optimize the toe angle in order to achieve a low electric propulsion power consumption while at the same time limiting the number of power consumption data sets that is used to determine the toe angle that is associated with the lowest electric propulsion power consumption.

Optionally, in this embodiment, the step of determining which toe angle is associated with the lowest electric propulsion power consumption additionally includes comparing at least one further power consumption data set with at least one of the first power consumption data set and the second power consumption data set and determining which of the first, second and further power consumption data sets indicates the lowest electric propulsion power consumption.

In an embodiment, in the method according to the first aspect of the invention, prior to the steps of generating a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the first toe angle, generating a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle, determining which toe angle is associated with the lowest electric propulsion power consumption and arranging the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption, the following computer-implemented steps are carried out:

- determining a driving situation parameter value,

- on the basis of the driving situation parameter value, determining whether to start carrying out the steps of generating a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the first toe angle, generating a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle, determining which toe angle is associated with the lowest electric propulsion power consumption and arranging the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption or not.

In this embodiment, it is first checked whether it is for example safe and useful to carry out an adjustment of the toe angle in order to obtain a low electric propulsion power consumption before actually initiating the toe angle adjustment procedure.

Optionally, the steps of this embodiment of the method according to the first aspect of the invention are carried out during driving.

In this embodiment, optionally the determination of the driving parameter value includes one or more of:

- determining the velocity and/or changes in velocity and/or expected velocity and/or expected changes in velocity of the electric vehicle over a time period or distance, and/or

- using navigation data, determining the expected amounts of steering actions for a coming time period or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination, and/or

- determining a vehicle vibration parameter, and/or

- determining a tire parameter, e.g. tire pressure and/or tire wear and/or tire type,

- determining a weather related parameter.

For example, the velocity of the vehicle may be influence how much energy efficiency can be gained by carrying out the method according to the first aspect of the invention. If the velocity is such that hardly any benefit is to be expected, it may be decided not to initiate the toe angle adjustment procedure.

For example, if the vehicle is used in driving through urban traffic with many velocity changes, starts/stops and turns, the amount of energy efficiency can be gained by carrying out the method according to the first aspect of the invention will be different than when driving on a highway at near constant velocity.

For example, navigation data from the navigation system can be used to determine the expected amounts of steering actions for a coming time period or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination. These are all examples of parameters that influence how much energy efficiency can be gained by carrying out the method according to the first aspect of the invention.

For example, a vehicle vibration parameter may be used as an indication whether the vehicle is driving on smooth roads or rough roads, which may influence how much energy efficiency can be gained by carrying out the method according to the first aspect of the invention. For example, a tire parameter, e.g. tire pressure and/or tire wear and/or tire type, may be determined in order to find out whether carrying out the toe angle adjustment procedure is likely to obtain sufficient benefits in terms of increasing energy efficiency.

For example, a weather parameter may be determined, either by directly measuring a weather parameter or by obtaining weather parameter data e.g. from weather forecasting websites, weather monitoring websites or weather forecasting services. Examples of weather parameters are wind speed, wind direction (optionally in relation to the driving direction), atmospheric pressure, amount and/or type of precipitation or expected precipitation.

Optionally, a score parameter value of a score parameter is determined which is based on multiple driving condition parameters values. Optionally, the score parameter value is based on weighted driving parameter values.

Optionally, the toe angle adjustment procedure is initiated only if a threshold value of a driving condition parameter or score parameter is exceeded.

Optionally, the steps of this embodiment are carried out at the start-up of the vehicle and/or when a destination is inputted in a navigation system and/or at a moment during driving when stable and/or constant driving conditions are expected.

In an embodiment, in the method according to the first aspect of the invention, prior to determining which toe angle is associated with the lowest electric propulsion power consumption and arranging the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption, the following computer-implemented steps are carried out:

- determining a driving situation parameter value,

- on the basis of the driving situation parameter value, determining whether to start carrying out the steps of determining which toe angle is associated with the lowest electric propulsion power consumption and arranging the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption or not.

In this embodiment, optionally the determination of the driving parameter value includes one or more of:

- determining the velocity and/or changes in velocity and/or expected velocity and/or expected changes in velocity of the electric vehicle over a time period or distance, and/or

- using navigation data, determining the expected amounts of steering actions for a coming time period or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination, and/or

- determining a vehicle vibration parameter, and/or

- determining a tire parameter, e.g. tire pressure and/or tire wear and/or tire type,

- determining a weather related parameter. In this embodiment, optionally power consumption data sets are already generated before it is decided whether or not to determine which toe angle is associated with the lowest electric propulsion power consumption and to arrange the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption.

In an embodiment of the method according to the first aspect of the invention, the method according to the first aspect of the invention is carried out in the first trip after maintenance and/or tire change. Alternatively or in addition, the method according to the first aspect of the invention is carried out after it has been established that the first wheel and/or the second wheel has been subjected to g-forces which were higher than normal, e.g. due to the respective wheel hitting a curb or a pothole in the road.

In an embodiment of the method according to the first aspect of the invention, the method according to the first aspect of the invention is carried out at the start-up of the vehicle and/or when a destination is inputted in a navigation system and/or at a moment during driving when stable and/or constant driving conditions are expected.

In an embodiment of the method according to the first aspect of the invention, the method according to the first aspect of the invention is carried out while driving at a constant speed.

In an embodiment of the method according to the first aspect of the invention, the method according to the first aspect of the invention is carried out while driving straight ahead.

In an embodiment of the method according to the first aspect of the invention, the method according to the first aspect of the invention is carried out while driving at a constant inclination.

In an embodiment of the method according to the first aspect of the invention, the method according to the first aspect of the invention is carried out while driving straight ahead at a constant speed and at a constant inclination.

In an embodiment of the method according to the first aspect of the invention, generating a first, second and/or further power consumption data set includes measuring electrical current and/or voltage that is provided by a traction battery of the electric vehicle.

Electrical current and electrical voltage are indicators of electric power consumption. Measuring one or both at the traction battery of the electrical vehicle, gives a direct indication of the electric propulsion power consumption. In an embodiment of the method according to the first aspect of the invention, generating a first, second and/or further power consumption data set includes measuring electric power consumption of at least one driven wheel of the electric vehicle.

Optionally, the method is carried out in an electric vehicle which comprises an in-wheel motor, and wherein generating a first, second and/or further power consumption data set includes measuring a parameter value which is indicative of electric power consumption by the in-wheel motor.

Optionally, the first wheel is a driven wheel, optionally driven by an in-wheel motor.

Optionally, generating a first, second and/or further power consumption data set includes measuring a parameter value which is indicative of electric power consumption of all driven wheels of the electric vehicle.

In an embodiment of the method according to the first aspect of the invention, a lateral acceleration parameter of the electric vehicle is monitored during driving. In case a value of a lateral acceleration parameter exceeds a threshold value, the first wheel, and optionally also the second wheel, is arranged into a stability toe angle.

A stability toe angle is a toe angle value which is known to result in good vehicle stability, e.g. good roadholding behaviour and/or stable straight line driving. The stability toe angle is for example a factory setting or other default setting, or a known compromise between vehicle stability and energy efficiency.

Alternatively, a stability toe angle, optionally a preferred stability toe angle, can be determined on a vehicle-specific basis.

This embodiment allows to switch from a toe angle that is optimised for energy efficiency to a toe angle that takes more account of vehicle stability when this is necessary.

In an embodiment of the method according to the first aspect of the invention, when a value of a lateral acceleration parameter exceeds a threshold value, a preferred stability toe angle is determined by:

- during driving, with a first wheel of the electric vehicle at a first stability test toe angle, generating a first lateral acceleration data set which is indicative for a real time lateral acceleration parameter value when the first wheel is at the first stability test toe angle,

- during driving, changing the toe angle of the first wheel to a second stability test toe angle which is different from the first stability test toe angle, and while the first wheel is at the second stability test toe angle, generating a second lateral acceleration parameter data set which is indicative for the real time lateral acceleration parameter value when the first wheel is at the second stability test toe angle, - determining which stability test toe angle is associated with the most advantageous value or values of the lateral acceleration parameter.

The stability test toe angle which is associated with the most advantageous value or values of the lateral acceleration parameter is the preferred stability toe angle.

Optionally, the lateral acceleration parameter is monitored during driving.

Optionally, the lateral acceleration parameter which exceeds a threshold value is the same as the parameter to which to real time lateral acceleration parameter value pertains. Alternatively, the lateral acceleration parameter which exceeds a threshold value is a different parameter than the parameter to which to real time lateral acceleration parameter value pertains.

Optionally, the first stability test toe angle is the toe angle at which the value of the lateral acceleration parameter exceeded the threshold value.

Optionally, the first stability test toe angle is the toe angle which is associated with the lowest electric propulsion power consumption, e.g. as determined in the method according to the first aspect of the invention.

Optionally, in this embodiment, the method further comprises the following steps:

- during driving, changing the toe angle of the first wheel to a further stability test toe angle which is different from the first stability test toe angle and from the second stability test toe angle, and generating a further lateral acceleration parameter data set which is indicative for the real time lateral acceleration parameter value when the first wheel is at the further stability test toe angle, and optionally repeating this step for one or more additional mutually different further stability test toe angles of the first wheel and therewith obtaining multiple further lateral acceleration parameter data sets, each lateral acceleration parameter data set being associated with a single further stability test toe angle.

Optionally, in a variant of this embodiment, the first stability test toe angle of the first wheel is combined with a first additional stability test toe angle of a second wheel when generating the lateral acceleration parameter data, the second wheel being a front wheel when the first wheel is a front wheel and the second wheel being a rear wheel when the first wheel is a rear wheel, and the first lateral acceleration parameter data being indicative for the real time lateral acceleration parameter value when the first wheel is at the first stability test toe angle and the second wheel is at the first stability test additional toe angle.

Alternatively or in addition, in this variant, the second stability test toe angle of the first wheel is combined with a second additional stability test toe angle of a second wheel when generating the second lateral acceleration parameter data, the second wheel being a front wheel when the first wheel is a front wheel and the second wheel being a rear wheel when the first wheel is a rear wheel, and the second lateral acceleration parameter data being indicative for the real time lateral acceleration parameter value when the first wheel is at the second stability test toe angle and the second wheel is at the second additional stability test toe angle,

Alternatively or in addition, in this variant, at least one further stability test toe angle of the first wheel is combined with a further additional stability test toe angle of a second wheel when generating the further lateral acceleration parameter data, the second wheel being a front wheel when the first wheel is a front wheel and the second wheel being a rear wheel when the first wheel is a rear wheel, and the respective further lateral acceleration parameter data being indicative for the real time lateral acceleration parameter value when the first wheel is at the at least one further stability test toe angle and the second wheel is at the further additional stability test toe angle.

Optionally, in this variant, after determining which stability test toe angle is associated with the most advantageous value or values of the lateral acceleration parameter, the first wheel is brought to a toe angle that corresponds to this stability test toe angle and the second wheel is brought into the additional stability test toe angle that is associated with this stability test toe angle.

Optionally, after bringing the first wheel in the stability test toe angle which is associated with the most advantageous value or values of the lateral acceleration parameter, the lateral acceleration parameter of the electric vehicle is monitored, and in case a value of the lateral acceleration parameter remains below a threshold value, the first wheel, and optionally also the second wheel, is brought back to a vehicle efficiency toe angle. Optionally, the monitoring takes place during a predetermined time period or distance travelled by the vehicle.

A vehicle efficiency toe angle is a toe angle which is selected on the basis of an advantageous level of electric propulsion power consumption.

Optionally, the vehicle efficiency toe angle is the toe angle that is associated with lowest electric propulsion power consumption, e.g. the toe angle that is associated with the lowest electric propulsion power consumption as determined in accordance with the first aspect of the invention.

This embodiment allows to switch from a toe angle that is optimised for energy efficiency to a toe angle that takes more account of vehicle stability when this is necessary, and allows to determine which toe angle is best for vehicle stability. When the vehicle is stable again, the toe angle can be switched back again to a toe angle that is optimised for energy efficiency.

This embodiment can also be carried out independently from the method according to claim 1.

In an embodiment, in the method according to the first aspect of the invention, prior to the steps of generating a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the first toe angle, generating a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle, determining which toe angle is associated with the lowest electric propulsion power consumption and arranging the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption, the following step is carried out:

- during driving, determining whether the toe angle of the first wheel is within a predetermined toe angle range, and if not, changing the toe angle of the first wheel such that the toe angle comes to lie within the predetermined toe angle range.

In an embodiment, the method according to the first aspect of the invention further includes correcting a generated power consumption data set for a driving condition that occurred during the generation of the power consumption data set.

For example, at least one a generated power consumption data set is corrected based on at least one driving condition parameter value, e.g. a value for vehicle velocity, average vehicle velocity over a time period or distance travelled by the vehicle, a weather-related parameter such as wind speed, wind direction relative to travel direction and/or atmospheric pressure, road conditions and/or tire pressure.

Optionally, at least one driving condition parameter value is measured or otherwise determined in real time during generation of at least one, optionally multiple or even all, power consumption data set(s). Optionally, alternatively or in addition, at least one driving condition parameter value is obtained from a website, e.g. a weather forecasting website or a weather monitoring website.

The first aspect of the invention further pertains to an active toe angle adjustment system for use in an electric vehicle, which system comprises:

- a first toe angle adjuster which is adapted to adjust the toe angle of a first wheel of an electric vehicle in which the active toe alignment system is arranged,

- a power consumption measurement system, which is adapted to generate propulsion power measurement data relating to real time electric propulsion power consumption of the vehicle,

- a toe angle controller which is configured to:

- from the power consumption measurement system, during driving, obtain a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a first toe angle

- during driving, instruct the first toe angle adjuster to change the toe angle of the first wheel to a second toe angle which is different from the first toe angle, - from the power consumption measurement system, during driving, obtain a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle,

- determining which toe angle is associated with the lowest electric propulsion power consumption,

- instruct the first toe angle adjuster to arrange the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption.

The active toe angle adjustment system according to the first aspect of the invention is suitable for use in an electric vehicle. The electric vehicle is for example a front wheel driven vehicle, a rear wheel driven vehicle, a four wheel driven vehicle or an all wheel driven vehicle. The electric vehicle may be powered by a central electric motor that supplies electrical propulsion power to all driven wheels of the vehicle. Alternatively or in addition, the electric vehicle may comprise an in-wheel electric motor for at least one driven wheel, optionally for all driven wheels. A hybrid vehicle is in the context of the invention also considered to be an electric vehicle when it runs in full electric mode. The electric vehicle optionally is a high efficiency electric vehicle. The electric vehicle is optionally a solar vehicle, i.e. an electric vehicle which is at least partly chargeable by means of solar cells which are integrated in the vehicle. Typically, such a solar vehicle comprises at least one traction battery for supplying electrical power to the electric motor or motors, and vehicle integrated solar cells for charging the traction battery. Additional charging of the traction battery via for example an external electrical power grid (e.g. the main power grid) is also possible.

The electric vehicle is for example a car (e.g. a passenger car), a delivery vehicle, a recreational vehicle or a van.

In the active toe angle adjustment system according to the first aspect of the invention, a toe angle adjuster is present which is adapted to adjust the toe angle of a first wheel of an electric vehicle in which the active toe alignment system is arranged. The first wheel is for example a front wheel or a rear wheel.

The toe angle adjuster is for example a dedicated toe angle adjuster. Alternatively, the toe angle adjuster is partly or fully integrated in the steering system of the electric vehicle.

Optionally, the toe angle adjuster comprises a steering rod length adjuster, which is adapted to adjust the length of a steering rod which extends between a left front wheel and a right front wheel.

The active toe angle adjustment system according to the first aspect of the invention further comprises a power consumption measurement system, which is adapted to generate propulsion power measurement data relating to real time electric propulsion power consumption of the vehicle. The power consumption measurement system optionally comprises at least one sensor device for measuring or otherwise determining a parameter value that is indicative and/or representative for the electric propulsion power consumption of the electric vehicle, either based on the parameter value as such or in combination with one or more other parameter values. A sensor device comprises at least a sensor, optionally in combination with for example a local data processor and/or data transmission device for sending measurement data to a central processor of the power consumption measurement system or directly to the toe angle controller.

Optionally, the power consumption measurement system comprises multiple sensor devices are arranged to measure or otherwise determine a parameter value that is indicative and/or representative for the electric propulsion power consumption of the electric vehicle at different locations within the electric vehicle.

Optionally, the power consumption measurement system comprises multiple sensor devices are arranged to measure or otherwise determine the parameter value of different parameters that are indicative and/or representative for the electric propulsion power consumption of the electric vehicle, either as such or in combination with other parameters.

Optionally, the power consumption measurement system comprises multiple sensor devices are arranged to measure or otherwise determine the parameter value of different parameters that are indicative and/or representative for the electric propulsion power consumption of the electric vehicle, which sensor devices are arranged at different locations within the electric vehicle.

The active toe angle adjustment system according to the first aspect of the invention further comprises a toe angle controller. The toe angle controller is configured to, during driving, obtain a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a first toe angle from the power consumption measurement system.

The first power consumption data set comprises at least a datapoint relating to a measured or otherwise determined value of a parameter that is indicative for the consumed electric propulsion power at the time of generating the data set (’’real time”) and a datapoint pertaining to the value of the first toe angle. The data pertaining to the value of the first toe angle can for example be received from the power consumption measurement system, from the toe angle adjuster or from a different source, e.g. from a vehicle control device. Electric propulsion power is the electric power that is used to propel the vehicle, e.g. the electric power to operate a central electric motor or one or more or all in-wheel motors of the electric vehicle.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set allows to establish or estimate how much electric power is consumed to propel the car. The parameter is for example measured instantaneously (i.e. at one discrete moment) or during a time period or over a certain distance travelled by the vehicle. Optionally, the first power consumption data set comprises processed values such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set.

For example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is determined by measuring the amount of electric propulsion power that is required for keeping the vehicle at a constant velocity or by interrupting the supply of electric propulsion power to the vehicle, e.g. to the wheels of the vehicle, and determining the length of the time period that passes before the velocity of the vehicle is reduced by a certain amount or percentage (e.g. 2 km/h or 1%). Alternatively or in addition, for example the one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined during regenerative braking, e.g. by determining (e.g. measuring) the amount of power that is supplied to the battery by the regenerative braking system, optionally in combination with determining the reduction in velocity of the vehicle, e.g. during the time the power supply to the battery by the regenerative braking system is determined.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is for example electric power, an electric current, an electric voltage, a combination of an electric current and an electric voltage. Optionally, the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is not only indicative but also representative for the consumed electric propulsion power at the time of generating the data set.

The first power consumption data set is generated during driving, i.e. during normal operation of the vehicle, so that a vehicle-specific power consumption data set is generated. The value or values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set may depend on various driving condition parameters, e.g. velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. Optionally, parameter values indicative or representative for one or more of such driving condition parameters are also comprised in the first power consumption data set.

The toe angle controller of the active toe angle adjustment system according to the first aspect of the invention is further configured to, during driving, instruct the first toe angle adjuster to change the toe angle of the first wheel to a second toe angle which is different from the first toe angle. The difference between the first and the second toe angle is for example 0.1° - 1.5° (both mentioned values included), e.g. 0.25°- 1.0° (both mentioned values included), for example 0.5°.

The toe angle controller of the active toe angle adjustment system according to the first aspect of the invention is further configured to, during driving, obtain from the power consumption measurement system a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle.

The second power consumption data set comprises at least a datapoint relating to a measured or otherwise determined value of a parameter that is indicative for the consumed electric propulsion power at the time of generating the data set (’’real time”) and a datapoint pertaining to the value of the second toe angle.

The second power consumption data set optionally comprises at least parameter values of parameters that are comprised in the first data set so that comparison of data in the first power consumption data set and data in the second power consumption data set is possible.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set allows to establish or estimate how much electric power is consumed to propel the car. The parameter is for example measured instantaneously (i.e. at one discrete moment) or during a time period or during a predetermined distance travelled by the vehicle. Optionally, the second power consumption data set comprises processed values such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set.

For example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is determined by measuring the amount of electric propulsion power that is required for keeping the vehicle at a constant velocity or by interrupting the supply of electric propulsion power to the vehicle, e.g. to the wheels of the vehicle, and determining the length of the time period that passes before the velocity of the vehicle is reduced by a certain amount or percentage (e.g. 2 km/h or 1%). Alternatively or in addition, for example the one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined during regenerative braking, e.g. by determining (e.g. measuring) the amount of power that is supplied to the battery by the regenerative braking system, optionally in combination with determining the reduction in velocity of the vehicle, e.g. during the time the power supply to the battery by the regenerative braking system is determined.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is for example electric power, an electric current, an electric voltage, a combination of an electric current and an electric voltage. Optionally, the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is not only indicative but also representative for the consumed electric propulsion power at the time of generating the data set.

The second power consumption data set is generated during driving, i.e. during normal operation of the vehicle, so that a vehicle-specific power consumption data set is generated. The value or values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set may depend on various driving condition parameters, e.g. velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. Optionally, parameter values indicative or representative for one or more of such driving condition parameters are also comprised in the second power consumption data set.

The toe angle controller of the active toe angle adjustment system according to the first aspect of the invention is further configured to determine which toe angle is associated with the lowest electric propulsion power consumption. This determination is carried out based on the first and second power consumption data sets, e.g. on the full power consumption data sets or on processed values in these power consumption data sets, such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set. For example, the average power consumption of the first power consumption data set and the average of the second power consumption data set are compared with each other.

The toe angle which is associated with the lowest electric propulsion power consumption can be for example be the first toe angle, the second toe angle or a toe angle that is different from the first and the second to angle. In the latter case, the toe angle that is associated with the lowest electric propulsion power consumption is determined by processing the first and second power consumption data set, e.g. based on further analysis of the power consumption datasets, which optionally includes a data analysis operation such as curve fitting. The toe angle which is associated with the lowest electric propulsion power consumption can be for example alternatively be determined on the basis of a straightforward comparison of the data in the first and second power consumption data sets. In practical cases, this determination will be carried out during driving. However, alternatively it may be carried out at a stop, e.g. at the next stop, of the vehicle.

The toe angle controller of the active toe angle adjustment system according to the first aspect of the invention is further configured to instruct the first toe angle adjuster to arrange the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption.

In practical cases, this instruction will be given during driving. However, alternatively it may be given at a stop, e.g. at the next stop, of the vehicle.

Optionally, the active toe angle adjustment system according to the first aspect of the invention is suitable for carrying out the method according to the first aspect of the invention, for example for carrying out the method according to the first aspect of the invention in accordance with any of the described embodiments and/or in accordance with any combination of the described embodiments

Optionally, the first power consumption data set is obtained by receiving raw data from a measurement device, e.g. from the power consumption measurement system, and transforming the raw data into a first power consumption data set, e.g. by a processor of the toe angle controller. Alternatively or in addition, at least a part of the first power consumption data set or the entire first power consumption data set is received by the toe angle controller, e.g. from a measurement device, for example from the power consumption measurement system,.

Optionally, the second power consumption data set is obtained by receiving raw data from a measurement device, e.g. from the power consumption measurement system, and transforming the raw data into a second power consumption data set, e.g. by a processor of the toe angle controller. Alternatively or in addition, at least a part of the second power consumption data set or the entire second power consumption data set is received by the toe angle controller, e.g. from a measurement device for example from the power consumption measurement system.

In an embodiment of the active toe angle adjustment system according to the first aspect of the invention, the toe controller of the active toe adjustment system according to the first aspect of the invention is further configured to, during driving:

- instruct the first toe angle adjuster to change the toe angle of the first wheel to a further toe angle which is different from the first toe angle and from the second toe angle, - from the power consumption measurement system, obtain a further power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a further toe angle.

In this embodiment, optionally the toe angle controller is configured to repeat these steps for one or more additional mutually different further toe angles of the first wheel. Therewith, multiple further power consumption data sets are obtained, each further power consumption data set being associated with a single further toe angle.

The difference between a further toe angle and the first, the second toe angle or a different further toe angle is for example 0.1° - 1.5° (both mentioned values included), e.g. 0.25°- 1.0° (both mentioned values included), for example 0.5°.

This embodiment provides more than two power consumption data sets, which allows to more accurately determine the toe angle that is associated with the lowest electric propulsion power consumption.

The further power consumption data set comprises at least a datapoint relating to a measured or otherwise determined value of a parameter that is indicative for the consumed electric propulsion power at the time of generating the data set (’’real time”) and a datapoint pertaining to the value of the further toe angle.

The further power consumption data set optionally comprises at least parameter values of parameters that are comprised in the first data set so that comparison of data in the first power consumption data set and data in the further power consumption data set is possible.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set allows to establish or estimate how much electric power is consumed to propel the car. The parameter is for example measured instantaneously (i.e. at one discrete moment) or during a time period or during a predetermined distance travelled by the vehicle. Optionally, the further power consumption data set comprises processed values such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set.

For example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is determined by measuring the amount of electric propulsion power that is required for keeping the vehicle at a constant velocity or by interrupting the supply of electric propulsion power to the vehicle, e.g. to the wheels of the vehicle, and determining the length of the time period that passes before the velocity of the vehicle is reduced by a certain amount or percentage (e.g. 2 km/h or 1%). Alternatively or in addition, for example the one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined during regenerative braking, e.g. by determining (e.g. measuring) the amount of power that is supplied to the battery by the regenerative braking system, optionally in combination with determining the reduction in velocity of the vehicle, e.g. during the time the power supply to the battery by the regenerative braking system is determined.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is for example electric power, an electric current, an electric voltage, a combination of an electric current and an electric voltage. Optionally, the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is not only indicative but also representative for the consumed electric propulsion power at the time of generating the data set.

The further power consumption data set is generated during driving, i.e. during normal operation of the vehicle, so that a vehicle-specific power consumption data set is generated. The value or values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set may depend on various driving condition parameters, e.g. velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. Optionally, parameter values indicative or representative for one or more of such driving condition parameters are also comprised in the further power consumption data set.

In an embodiment of the active toe angle adjustment system according to the first aspect of the invention, the first toe angle adjuster of the active toe adjustment system according to the first aspect of the invention is, comprises or forms part of a steer-by-wire system.

This way, little or no additional parts have to be added to the electric vehicle, which save weight and is beneficial for obtaining a good energy efficiency.

In an embodiment of the active toe angle adjustment system according to the first aspect of the invention, the toe angle controller is configured to, during driving:

- in determining which toe angle is associated with the lowest electric propulsion power consumption, comparing the first power consumption data set and the second power consumption data set with each other, and determining which power consumption data set indicates the lowest electric propulsion power consumption.

This is a straightforward way of determining which power consumption data set indicates the lowest electric propulsion power consumption, requiring little computer power and data processing power. Optionally, in this embodiment, the first wheel is arranged into the first or the second toe angle after determination which of these toe angles is associated with the lowest electric propulsion power consumption.

In an embodiment of the active toe angle adjustment system according to the first aspect of the invention, the toe angle controller is configured to, during driving:

- instruct the first toe angle adjuster to change the toe angle of the first wheel to a further toe angle which is different from the first toe angle and from the second toe angle,

- from the power consumption measurement system, obtain a further power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a further toe angle,

- in determining which toe angle is associated with the lowest electric propulsion power consumption, comparing at least one further power consumption data set with at least one of the first power consumption data set and the second power consumption data set and determining which of the first, second and further power consumption data sets indicates the lowest electric propulsion power consumption.

For example, first the first power consumption data set and the second power consumption data set are compared with each other, and it is determined which of these two power consumption data sets is associated with the lowest electric propulsion power consumption, and then that power consumption data set is compared to the further power consumption data set.

This is a straightforward way of determining which power consumption data set indicates the lowest electric propulsion power consumption, requiring little computer power and data processing power.

Optionally, in this embodiment, the first wheel is arranged into the first or the second toe angle or the further toe angle after determination which of these toe angles is associated with the lowest electric propulsion power consumption.

In an embodiment of the active toe angle adjustment system according to the first aspect of the invention, the toe angle controller is configured to, during driving:

- instruct the first toe angle adjuster to change the toe angle of the first wheel to a further toe angle which is different from the first toe angle and from the second toe angle,

- from the power consumption measurement system, obtain a further power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a further toe angle,

- in determining which toe angle is associated with the lowest electric propulsion power consumption, determining a relation between the toe angle and the electric propulsion power consumption based on the generated power consumption data sets, e.g. through curve fitting, and selecting the toe angle that is associated with the lowest electric propulsion power consumption on the basis of this determined relation.

This embodiment may result in arranging the first wheel at a toe angle which is different from the first, second and further toe angle, in case the determined relation between the toe angle and the electric propulsion power consumption shows that e.g. an intermediate toe angle provides a lower electric propulsion power consumption.

This embodiment allows to further optimize the toe angle in order to achieve a low electric propulsion power consumption while at the same time limiting the number of power consumption data sets that is used to determine the toe angle that is associated with the lowest electric propulsion power consumption.

Optionally, in this embodiment, the toe angle controller is configured to additionally include comparing at least one further power consumption data set with at least one of the first power consumption data set and the second power consumption data set and determining which of the first, second and further power consumption data sets indicates the lowest electric propulsion power consumption in the step of determining which toe angle is associated with the lowest electric propulsion power consumption.

In an embodiment of the active toe angle adjustment system according to the first aspect of the invention, the toe angle controller is further configured to:

- receive data which pertains to a driving situation parameter value,

- on the basis of the driving situation parameter value, determining whether to initiate the determination which toe angle is associated with the lowest electric propulsion power consumption.

In this embodiment, it is first checked whether it is for example safe and useful to carry out an adjustment of the toe angle in order to obtain a low electric propulsion power consumption before actually initiating the toe angle adjustment procedure.

In this embodiment, optionally power consumption data sets are already generated before it is decided whether or not to determine which toe angle is associated with the lowest electric propulsion power consumption and to arrange the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption.

Optionally the data pertaining to the driving parameter value includes one or more of:

- the velocity and/or changes in velocity and/or expected velocity and/or expected changes in velocity of the electric vehicle over a time period and/or distance, and/or

- based on navigation data, the expected amounts of steering actions for a coming time period and/or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination, and/or - a vehicle vibration parameter, and/or

- a tire parameter, e.g. tire pressure and/or tire wear and/or tire type, and/or

- a weather related parameter.

In this embodiment, optionally the determination of the driving parameter value includes one or more of:

- determining the velocity and/or changes in velocity and/or expected velocity and/or expected changes in velocity of the electric vehicle over a time period or distance, and/or

- using navigation data, determining the expected amounts of steering actions for a coming time period or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination, and/or

- determining a vehicle vibration parameter, and/or

- determining a tire parameter, e.g. tire pressure and/or tire wear and/or tire type,

- determining a weather related parameter.

For example, the velocity of the vehicle may be influence how much energy efficiency can be gained by carrying out the method according to the first aspect of the invention. If the velocity is such that hardly any benefit is to be expected, it may be decided not to initiate the toe angle adjustment procedure.

For example, if the vehicle is used in driving through urban traffic with many velocity changes, starts/stops and turns, the amount of energy efficiency can be gained by carrying out the method according to the first aspect of the invention will be different than when driving on a highway at near constant velocity.

For example, navigation data from the navigation system can be used to determine the expected amounts of steering actions for a coming time period or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination. These are all examples of parameters that influence how much energy efficiency can be gained by carrying out the method according to the first aspect of the invention.

For example, a vehicle vibration parameter may be used as an indication whether the vehicle is driving on smooth roads or rough roads, which may influence how much energy efficiency can be gained by carrying out the method according to the first aspect of the invention.

For example, a tire parameter, e.g. tire pressure and/or tire wear and/or tire type, may be determined in order to find out whether carrying out the toe angle adjustment procedure is likely to obtain sufficient benefits in terms of increasing energy efficiency.

For example, a weather parameter may be determined, either by directly measuring a weather parameter or by obtaining weather parameter data e.g. from weather forecasting websites, weather monitoring websites or weather forecasting services. Examples of weather parameters are wind speed, wind direction (optionally in relation to the driving direction), atmospheric pressure, amount and/or type of precipitation or expected precipitation.

Optionally, a score parameter value of a score parameter is determined which is based on multiple driving condition parameters values. Optionally, the score parameter value is based on weighted driving parameter values.

Optionally, the toe angle adjustment procedure is initiated only if a threshold value of a driving condition parameter or score parameter is exceeded.

Optionally, the steps of this embodiment are carried out at the start-up of the vehicle and/or when a destination is inputted in a navigation system and/or at a moment during driving when stable and/or constant driving conditions are expected.

In an embodiment of the active toe angle adjustment system according to the first aspect of the invention, the toe angle controller is further configured to:

- receive data which pertains to a driving situation parameter value,

- on the basis of the driving situation parameter value, determining whether to initiate obtaining a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a first toe angle.

In this embodiment, it is first checked whether it is for example safe and useful to carry out an adjustment of the toe angle in order to obtain a low electric propulsion power consumption before actually initiating the toe angle adjustment procedure.

Optionally the data pertaining to the driving parameter value includes one or more of:

- the velocity and/or changes in velocity and/or expected velocity and/or expected changes in velocity of the electric vehicle over a time period and/or distance, and/or

- based on navigation data, the expected amounts of steering actions for a coming time period and/or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination, and/or

- a vehicle vibration parameter, and/or

- a tire parameter, e.g. tire pressure and/or tire wear and/or tire type, and/or

- a weather related parameter.

In this embodiment, optionally the determination of the driving parameter value includes one or more of:

- determining the velocity and/or changes in velocity and/or expected velocity and/or expected changes in velocity of the electric vehicle over a time period or distance, and/or

- using navigation data, determining the expected amounts of steering actions for a coming time period or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination, and/or

- determining a vehicle vibration parameter, and/or - determining a tire parameter, e.g. tire pressure and/or tire wear and/or tire type,

- determining a weather related parameter.

In an embodiment of the active toe angle adjustment system according to the first aspect of the invention, the power consumption measurement system comprises a sensor device for measuring electrical current. This sensor device is arranged to measure the electrical current that is provided by a traction battery of an electric vehicle in which the active toe angle adjustment system is arranged.

Alternatively or in addition, the power consumption measurement system comprises a sensor device for measuring voltage. This sensor device is arranged to measure the voltage that is provided by a traction battery of the electric vehicle in which the active toe angle adjustment system is arranged.

Electrical current and electrical voltage are reliable indicators of electric power consumption. Measuring one or both at the traction battery of the electrical vehicle, gives a direct indication of the electric propulsion power consumption.

In an embodiment of the active toe angle adjustment system according to the first aspect of the invention, the power consumption measurement system comprises a sensor device which is adapted to measure a parameter value which is indicative of electric power consumption by an in-wheel motor of the electric vehicle in which the active toe angle adjustment system is arranged.

The electrical power that is consumed by an in-wheel motor and/or by the in-wheel motors of the electric vehicle is a reliable indicator of the electric propulsion power consumption of the electric vehicle.

In an embodiment of the active toe angle adjustment system according to the first aspect of the invention, the toe angle controller is further configured to, during driving:

- obtain a first lateral acceleration data set which is indicative for a real time lateral acceleration parameter value when the first wheel is at a first stability test toe angle,

- instruct the first toe angle adjuster to change the toe angle of the first wheel to a second stability test toe angle which is different from the first stability test toe angle,

- obtain a second lateral acceleration data set which is indicative for a real time lateral acceleration parameter value when the first wheel is at the second stability test toe angle,

- determine which stability test toe angle is associated with the most advantageous value or values of the lateral acceleration parameter.

Optionally, the toe angle controller is further configured to: - instruct the first toe angle adjuster to arrange the first wheel at stability test toe angle is associated with the most advantageous value or values of the lateral acceleration parameter.

Optionally, the toe angle controller is configured to monitor the lateral acceleration parameter during driving.

Optionally, the lateral acceleration parameter which exceeds a threshold value is the same as the parameter to which to real time lateral acceleration parameter value pertains. Alternatively, the lateral acceleration parameter which exceeds a threshold value is a different parameter than the parameter to which to real time lateral acceleration parameter value pertains.

Optionally, the first stability test toe angle is the toe angle at which the value of the lateral acceleration parameter exceeded the threshold value.

Optionally, the first stability test toe angle is the toe angle which is associated with the lowest electric propulsion power consumption, e.g. as determined in the method according to the first aspect of the invention.

Optionally, in this embodiment, the toe angle controller is further configured to:

- during driving, changing the toe angle of the first wheel to a further stability test toe angle which is different from the first stability test toe angle and from the second stability test toe angle, and generating a further lateral acceleration parameter data set which is indicative for the real time lateral acceleration parameter value when the first wheel is at the further stability test toe angle, and optionally repeating this step for one or more additional mutually different further stability test toe angles of the first wheel and therewith obtaining multiple further lateral acceleration parameter data sets, each lateral acceleration parameter data set being associated with a single further stability test toe angle.

Optionally, in a variant of this embodiment, the first stability test toe angle of the first wheel is combined with a first additional stability test toe angle of a second wheel when generating the lateral acceleration parameter data, the second wheel being a front wheel when the first wheel is a front wheel and the second wheel being a rear wheel when the first wheel is a rear wheel, and the first lateral acceleration parameter data being indicative for the real time lateral acceleration parameter value when the first wheel is at the first stability test toe angle and the second wheel is at the first stability test additional toe angle.

Alternatively or in addition, in this variant, the second stability test toe angle of the first wheel is combined with a second additional stability test toe angle of a second wheel when generating the second lateral acceleration parameter data, the second wheel being a front wheel when the first wheel is a front wheel and the second wheel being a rear wheel when the first wheel is a rear wheel, and the second lateral acceleration parameter data being indicative for the real time lateral acceleration parameter value when the first wheel is at the second stability test toe angle and the second wheel is at the second additional stability test toe angle,

Alternatively or in addition, in this variant, at least one further stability test toe angle of the first wheel is combined with a further additional stability test toe angle of a second wheel when generating the further lateral acceleration parameter data, the second wheel being a front wheel when the first wheel is a front wheel and the second wheel being a rear wheel when the first wheel is a rear wheel, and the respective further lateral acceleration parameter data being indicative for the real time lateral acceleration parameter value when the first wheel is at the at least one further stability test toe angle and the second wheel is at the further additional stability test toe angle.

Optionally, in this variant, the toe angle controller is configured to, after determining which stability test toe angle is associated with the most advantageous value or values of the lateral acceleration parameter, instruct he first toe angle adjuster to bring the first wheel into a toe angle that corresponds to this stability test toe angle and instruct the second toe angle adjuster to bring the second wheel into the additional stability test toe angle that is associated with this stability test toe angle.

Optionally, the toe angle controller is configured to, after instructing the first toe angle adjuster to bring the first wheel in the stability test toe angle which is associated with the most advantageous value or values of the lateral acceleration parameter, monitor the lateral acceleration parameter of the electric vehicle, and in case a value of the lateral acceleration parameter remains below a threshold value, and to instruct the first toe angle adjuster to bring back the first wheel, to a vehicle efficiency toe angle. Optionally, the monitoring takes place during a predetermined time period or distance travelled by the vehicle.

A vehicle efficiency toe angle is a toe angle which is selected on the basis of an advantageous level of electric propulsion power consumption.

Optionally, the vehicle efficiency toe angle is the toe angle that is associated with lowest electric propulsion power consumption, e.g. the toe angle that is associated with the lowest electric propulsion power consumption as determined in accordance with the first aspect of the invention.

This embodiment allows to switch from a toe angle that is optimised for energy efficiency to a toe angle that takes more account of vehicle stability when this is necessary, and allows to determine which toe angle is best for vehicle stability. When the vehicle is stable again, the toe angle can be switched back again to a toe angle that is optimised for energy efficiency.

In an embodiment of the active toe angle adjustment system according to the first aspect of the invention, the toe angle controller is further configured to: - correct a generated power consumption data set for a driving condition that occurred during the generation of the power consumption data set.

For example, the toe angle controller is configured to correct at least one a generated power consumption data set based on at least one driving condition parameter value, e.g. a value for vehicle velocity, average vehicle velocity over a time period or distance travelled by the vehicle, a weather-related parameter such as wind speed, wind direction relative to travel direction and/or atmospheric pressure, road conditions and/or tire pressure.

Optionally, the active toe angle adjustment system according to the first aspect of the invention comprises at least one sensor device which is adapted to measure or otherwise determine at least one driving condition parameter in real time during generation of at least one, optionally multiple or even all, power consumption data set(s). Optionally, alternatively or in addition, at least one driving condition parameter value is obtained from a website, e.g. a weather forecasting website or a weather monitoring website.

The first aspect of the invention further pertains to an active toe angle adjustment system for use in an electric vehicle, which system comprises:

- a first toe angle adjuster which is adapted to adjust the toe angle of a first wheel of an electric vehicle in which the active toe alignment system is arranged,

- a second toe angle adjuster which is adapted to adjust the toe angle of a second wheel of the electric vehicle in which the active toe alignment system is arranged, which second wheel is a front wheel if the first wheel is a front wheel and which second wheel is a rear wheel if the first wheel is a rear wheel,

- a power consumption measurement system, which is adapted to generate propulsion power measurement data relating to real time electric propulsion power consumption of the vehicle,

- a toe angle controller which is configured to:

- from the power consumption measurement system, during driving obtain a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a first toe angle and the second wheel is at a first additional toe angle,

- during driving, instruct the first toe angle adjuster to change the toe angle of the first wheel to a second toe angle which is different from the first toe angle,

- during driving, instruct the second toe angle adjuster to change the toe angle of the second wheel to a second additional toe angle which is different from the first additional toe angle, - from the power consumption measurement system, during driving, obtain a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle and the second wheel is at a second additional toe angle,

- determine which combination of toe angle of the first wheel and additional toe angle of the second wheel is associated with the lowest electric propulsion power consumption,

- instruct the first toe angle adjuster to arrange the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption, and

- instruct the second toe angle adjuster to arrange the second wheel at the additional toe angle that is associated with the lowest electric propulsion power consumption.

This active toe angle adjustment system can be combined with any of the embodiments of the active toe adjustment system according to the first aspect of the invention that is described above and/or below.

In this active toe angle adjustment system according to the first aspect of the invention, the toe angle of the first wheel and the toe angle of a second wheel are taken into consideration simultaneously.

In this active toe angle adjustment system according to the first aspect of the invention, the first toe angle of the first wheel is combined with a first additional toe angle of a second wheel when generating the first power consumption data set. In this active toe angle adjustment system, the second wheel is a front wheel when the first wheel is a front wheel and the second wheel is a rear wheel when the first wheel is a rear wheel. The first power consumption data set is indicative for real time electric propulsion power consumption when the first wheel is at the first toe angle and the second wheel is at the first additional toe angle.

Alternatively or in addition, in this active toe angle adjustment system, the second toe angle of the first wheel is combined with a second additional toe angle of a second wheel when generating the second power consumption data set. In this active toe angle adjustment system, the second wheel is a front wheel when the first wheel is a front wheel and the second wheel is a rear wheel when the first wheel is a rear wheel. The second power consumption data set is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle and the second wheel is at the second additional toe angle.

Alternatively or in addition, in this active toe angle adjustment system, at least one further toe angle of the first wheel is combined with a further additional toe angle of a second wheel when generating the further power consumption data set. In this active toe angle adjustment system, the second wheel is a front wheel when the first wheel is a front wheel and the second wheel is a rear wheel when the first wheel is a rear wheel. The respective further power consumption data set is indicative for real time electric propulsion power consumption when the first wheel is at the at least one further toe angle and the second wheel is at the further additional toe angle.

In this active toe angle adjustment system, the toe angle of e.g. the left front wheel and the right front wheel, and/or the left rear wheel and the right rear wheel are considered in combination with each other when generating art least one, an optionally multiple or all, power consumption data set(s). This is likely to provide a more accurate outcome of the determination of the optimal setting of the toe angle and additional toe angle in order to obtain the lowest electric propulsion power consumption.

In this active toe angle adjustment system, optionally the toe angle controller is configured to instruct the second toe angle adjuster to arrange the second wheel at the additional toe angle that is associated with the lowest electric propulsion power consumption. So, in this case, the combination of the toe angle of the first wheel and additional toe angle of the second wheel that is associated with the lowest electric propulsion power consumption is determined, and the first wheel is arranged at the toe angle associated with this combination and the second wheel is arranged at the additional toe angle that is associated with this same combination. For example, the first wheel is arranged at the first toe angle and the second wheel is arranged at the first additional toe angle if it turns out that the combination of the first toe angle and the first additional toe angle is associated with the lowest electric propulsion power consumption, or the first wheel is arranged at the second toe angle and the second wheel is arranged at the second additional toe angle if it turns out that the combination of the second toe angle and the second additional toe angle is associated with the lowest electric propulsion power consumption, or the first wheel is arranged at a further toe angle and the second wheel is arranged at the further additional toe angle that is associated with this particular further toe angle if it turns out that the combination of the further toe angle and the associated further additional toe angle is associated with the lowest electric propulsion power consumption.

In this active toe angle adjustment system, optionally the first toe angle and the first additional toe angle have the same value but are opposite in direction. For example, the first toe angle is 0.5°and the first additional toe angle is -0.5°. Alternatively, optionally the first toe angle and the first additional toe angle do not have the same value but still are opposite in direction. For example, the first toe angle is 0.45°and the first additional toe angle is -0.55°. This may occur e.g. due to a different wear pattern in the left and right tire. In this case, additional steering corrections may be required.

Likewise, optionally the second toe angle and the second additional toe angle have the same value but are opposite in direction. For example, the second toe angle is 0.5°and the second additional toe angle is -0.5°. Alternatively, optionally the second toe angle and the second additional toe angle do not have the same value but still are opposite in direction. For example, the second toe angle is 0.45°and the second additional toe angle is -0.55°.

Likewise, optionally the further toe angle and the further additional toe angle have the same value but are opposite in direction. For example, the further toe angle is 0.5°and the further additional toe angle is -0.5°. Alternatively, optionally the further toe angle and the further additional toe angle do not have the same value but still are opposite in direction. For example, the further toe angle is 0.45°and the further additional toe angle is -0.55°.

In a variant of this active toe angle adjustment system, the first toe angle of the first wheel is combined with a first additional toe angle of a second wheel when generating the first power consumption data set, and the second toe angle of the first wheel is combined with a second additional toe angle of a second wheel when generating the second power consumption data set, and at least one further toe angle of the first wheel is combined with a further additional toe angle of a second wheel when generating the further power consumption data set. In this variant, optionally, the first toe angle is the same as the second toe angle, and the first additional toe angle is different from the second additional toe angle, and the further toe angle is different from the first toe angle and from the second toe angle, and the further additional toe angle is the same as either the first additional toe angle or the second additional toe angle. Alternatively, the first toe angle, second toe angle and further toe angle(s) are all different from each other and the first additional toe angle, second additional toe angle and further additional toe angle(s) are also all different from each other.

The first aspect of the invention further pertains to an electric vehicle comprising a first wheel, and an active toe angle adjustment system according to the first aspect of the invention. In this electric vehicle, the first toe angle adjuster of the active toe angle adjustment system is connected to the first wheel.

In an embodiment, the electric vehicle according to the first aspect of the invention comprises a traction battery. In this embodiment, the power consumption measurement system of the active toe angle adjustment system comprises a sensor device for measuring electrical current. This sensor device is arranged to measure the electrical current that is provided by a traction battery of an electric vehicle in which the active toe angle adjustment system is arranged. Alternatively or in addition, the power consumption measurement system comprises a sensor device for measuring voltage. This sensor device is arranged to measure the voltage that is provided by a traction battery of the electric vehicle in which the active toe angle adjustment system is arranged. In this embodiment, the sensor device for measuring electrical current and/or the sensor for measuring voltage are arranged at or near an electrical wire that is connected to the traction battery.

Electrical current and electrical voltage are reliable indicators of electric power consumption. Measuring one or both at the traction battery of the electrical vehicle, gives a direct indication of the electric propulsion power consumption.

In an embodiment, the electric vehicle according to the first aspect of the invention comprises an in-wheel motor. Optionally, the in-wheel motor is arranged in, part of or at least associated with the first wheel. In this embodiment, the power consumption measurement system of the active toe angle adjustment system comprises a sensor device which is adapted to measure a parameter value which is indicative of electric power consumption by an in-wheel motor of the electric vehicle in which the active toe angle adjustment system is arranged. In this embodiment, the sensor device which is adapted to measure a parameter value which is indicative of electric power consumption by the in-wheel motor is arranged at the in-wheel motor and/or at an electric feed cable of the in-wheel motor.

The electrical power that is consumed by an in-wheel motor and/or by the in-wheel motors of the electric vehicle is a reliable indicator of the electric propulsion power consumption of the electric vehicle.

In an embodiment, the electric vehicle according to the first aspect of the invention comprises the electric vehicle comprises a driving condition sensor device, which is adapted to generate driving condition parameter data. In this embodiment, the toe angle controller of the active toe angle adjustment system is further configured to correct a generated power consumption data set for a driving condition that occurred during the generation of the power consumption data set.

In this embodiment, the driving condition sensor device is adapted to transmit driving condition parameter data to the toe angle controller of the active toe angle adjustment system for correcting a generated power consumption data set for a driving condition that occurred during the generation of the power consumption data set.

In an embodiment, the electric vehicle according to the first aspect of the invention electric vehicle comprises a steer-by-wire system. The first toe angle adjuster of the active toe angle adjustment system and optionally the second toe angle adjuster of the active toe angle adjustment system is connected to or integrated in the steer-by-wire system. The first aspect of the invention further pertains to a computer program comprising instructions which, when the program is executed by a processor of a toe angle controller of an active toe angle adjustment system according to the first aspect of the invention, cause the toe angle controller of the active toe angle adjustment system to carry out the following steps:

- from the power consumption measurement system of the active toe angle adjustment system, during driving, obtain a first power consumption data set which is indicative for real time electric propulsion power consumption when a first wheel is at a first toe angle,

- during driving, instruct the first toe angle adjuster of the active toe angle adjustment system to change the toe angle of the first wheel to a second toe angle which is different from the first toe angle,

- from the power consumption measurement system of the active toe angle adjustment system, during driving, obtain a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle,

- determine which toe angle is associated with the lowest electric propulsion power consumption,

- instruct the first toe angle adjuster of the active toe angle adjustment system to arrange the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption.

In an embodiment, the computer program according to the first aspect of the invention comprises instructions which, when the program is executed by a processor of the toe angle controller of the active toe angle adjustment system according to the first aspect of the invention wherein the toe angle controller is further configured to, during driving:

- instruct the first toe angle adjuster to change the toe angle of the first wheel to a further toe angle which is different from the first toe angle and from the second toe angle,

- from the power consumption measurement system, obtain a further power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a further toe angle, cause the toe angle controller of the active toe angle adjustment system to carry out the following steps:

- during driving, instruct the first toe angle adjuster of the active toe angle adjustment system to change the toe angle of the first wheel to a further toe angle which is different from the first toe angle and from the second toe angle,

- from the power consumption measurement system of the active toe angle adjustment system, during driving, obtain a further power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a further toe angle, - during driving, determine which toe angle is associated with the lowest electric propulsion power consumption.

In an embodiment, the computer program according to the first aspect of the invention comprises instructions which, when the program is executed by a processor of the toe angle controller of an active toe angle adjustment system according to the first aspect of the invention wherein the toe angle controller is further configured to receive data which pertains to a driving situation parameter value, and on the basis of the driving situation parameter value, determining whether to initiate the determination which toe angle is associated with the lowest electric propulsion power consumption, cause the toe angle controller of the active toe angle adjustment system to carry out the following steps:

- receive data which pertains to a driving situation parameter value,

- on the basis of the driving situation parameter value, determining whether to initiate the determination which toe angle is associated with the lowest electric propulsion power consumption, wherein optionally the data pertaining to the driving parameter value includes one or more of:

- the velocity and/or changes in velocity and/or expected velocity and/or expected changes in velocity of the electric vehicle over a time period, and/or

- based on navigation data, the expected amounts of steering actions for a coming time period and/or the expected type of roads to be travelled and/or the remaining distance to a set destination, and/or

- a vehicle vibration parameter, and/or

- a tire parameter, e.g. tire pressure and/or tire wear and/or tire type, and/or

- a weather related parameter.

In an embodiment, the computer program according to the first aspect of the invention comprises instructions which, when the program is executed by a processor of the toe angle controller of an active toe angle adjustment system according to the first aspect of the invention wherein the toe angle controller is further configured to, during driving:

- obtain a first lateral acceleration data set which is indicative for a real time lateral acceleration parameter value when the first wheel is at a first stability test toe angle,

- instruct the first toe angle adjuster to change the toe angle of the first wheel to a second stability test toe angle which is different from the first stability test toe angle,

- obtain a second lateral acceleration data set which is indicative for a real time lateral acceleration parameter value when the first wheel is at the second stability test toe angle, - determine which stability test toe angle is associated with the most advantageous value or values of the lateral acceleration parameter, cause the toe angle controller of the active toe angle adjustment system to carry out the following steps:

- during driving, obtain a first lateral acceleration data set which is indicative for a real time lateral acceleration parameter value when the first wheel is at a first stability test toe angle,

- during driving, instruct the first toe angle adjuster to change the toe angle of the first wheel to a second stability test toe angle which is different from the first stability test toe angle,

- during driving, obtain a second lateral acceleration data set which is indicative for a real time lateral acceleration parameter value when the first wheel is at the second stability test toe angle,

- during driving, determine the stability test toe angle that is associated with the most advantageous value or values of the lateral acceleration parameter, and

- optionally, during driving instruct the first toe angle adjuster to arrange the first wheel at the stability test toe angle that is associated with the most advantageous value or values of the lateral acceleration parameter.

In an embodiment, the computer program according to the first aspect of the invention comprises instructions which, when the program is executed by a processor of the toe angle controller of an active toe angle adjustment system according to the first aspect of the invention, cause the toe angle controller of the active toe angle adjustment system to carry out the following steps:

- when during driving determining which toe angle is associated with the lowest electric propulsion power consumption, comparing the first power consumption data set and the second power consumption data set with each other, and determining which power consumption data set indicates the lowest electric propulsion power consumption.

In an embodiment, the computer program according to the first aspect of the invention comprises instructions which, when the program is executed by a processor of the toe angle controller of an active toe angle adjustment system according to the first aspect of the invention wherein the toe angle controller is further configured to, during driving:

- instruct the first toe angle adjuster to change the toe angle of the first wheel to a further toe angle which is different from the first toe angle and from the second toe angle, - from the power consumption measurement system, obtain a further power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a further toe angle, cause the toe angle controller of the active toe angle adjustment system to carry out the following steps:

- when during driving determining which toe angle is associated with the lowest electric propulsion power consumption, comparing at least one further power consumption data set with at least one of the first power consumption data set and the second power consumption data set and determining which of the first, second and further power consumption data sets indicates the lowest electric propulsion power consumption, and/or

- when during driving determining which toe angle is associated with the lowest electric propulsion power consumption, determining a relation between the toe angle and the electric propulsion power consumption based on the generated power consumption data sets, e.g. through curve fitting, and selecting the toe angle that is associated with the lowest electric propulsion power consumption on the basis of this determined relation.

The first aspect of the invention further pertains to a computer program comprising instructions which, when the program is executed by a processor of the toe angle controller of an active toe angle adjustment system according to the first aspect of the invention, which system comprises:

- a first toe angle adjuster which is adapted to adjust the toe angle of a first wheel of an electric vehicle in which the active toe alignment system is arranged,

- a second toe angle adjuster which is adapted to adjust the toe angle of a second wheel of the electric vehicle in which the active toe alignment system is arranged, which second wheel is a front wheel if the first wheel is a front wheel and which second wheel is a rear wheel if the first wheel is a rear wheel,

- a power consumption measurement system, which is adapted to generate propulsion power measurement data relating to real time electric propulsion power consumption of the vehicle,

- a toe angle controller which is configured to, during driving:

- from the power consumption measurement system, obtain a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a first toe angle and the second wheel is at a first additional toe angle,

- instruct the first toe angle adjuster to change the toe angle of the first wheel to a second toe angle which is different from the first toe angle, - instruct the second toe angle adjuster to change the toe angle of the second wheel to a second additional toe angle which is different from the first additional toe angle,

- from the power consumption measurement system, obtain a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle and the second wheel is at a second additional toe angle,

- determine which combination of toe angle of the first wheel and additional toe angle of the second wheel is associated with the lowest electric propulsion power consumption,

- instruct the first toe angle adjuster to arrange the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption, and

- instruct the second toe angle adjuster to arrange the second wheel at the additional toe angle that is associated with the lowest electric propulsion power consumption, cause the toe angle controller of the active toe angle adjustment system to carry out the following steps:

- from the power consumption measurement system, during driving obtain a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a first toe angle and the second wheel is at a first additional toe angle,

- during driving instruct the first toe angle adjuster to change the toe angle of the first wheel to a second toe angle which is different from the first toe angle,

- during driving instruct the second toe angle adjuster to change the toe angle of the second wheel to a second additional toe angle which is different from the first additional toe angle,

- from the power consumption measurement system, during driving obtain a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at the second toe angle and the second wheel is at a second additional toe angle,

- determine which combination of toe angle of the first wheel and additional toe angle of the second wheel is associated with the lowest electric propulsion power consumption,

- instruct the first toe angle adjuster to arrange the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption, and

- instruct the second toe angle adjuster to arrange the second wheel at the additional toe angle that is associated with the lowest electric propulsion power consumption. The invention will be described in more detail below under reference to the drawing, in which in a non-limiting manner exemplary embodiments of the invention will be shown. The drawing shows in:

Fig. 1 : schematically, in top view, an electric vehicle with the front wheels in a toe-in position,

Fig. 2: schematically, in top view, an electric vehicle with the front wheels in a toe-out position,

Fig. 3: schematically, a first embodiment of an active toe angle adjustment system according to the first aspect of the invention,

Fig. 4: schematically, a variant of the embodiment of fig. 3,

Fig. 5, Fig. 6 and Fig. 7: schematically, subsequent steps in an embodiment of the method according to the first aspect of the invention,

Fig. 1 shows, schematically, in top view, an electric vehicle with the front wheels in a toe-in position. Fig. 2 shows, schematically, in top view, an electric vehicle with the front wheels in a toe-out position.

Fig.1 and fig. 2 show a top view of the front side of an electric vehicle 1. The electric vehicle 1 has a left front wheel 2 and a right front wheel 3.

The toe angle is the angle a1 , a2 in a horizontal plane, at which a wheel 2, 3 of a vehicle 1 is arranged relative to the horizontal longitudinal axis 4 of that vehicle when the vehicle is driving in a straight line (i.e. when the vehicle does not turn a corner). The toe angle a1, a2 relates to the angle of rotation of the wheel around a vertical rotation axis. In fig. 1 and fig. 2, lines 5 represent the position of the wheels 2,3. The lines 5 are horizontal center lines of the respective wheels 2,3

The angle in a horizontal plane between the left front wheel and the right front wheel is referred to as the combined front toe angle a3. The angle in a horizontal plane between the left rear wheel and the right rear wheel is referred to as the combined rear toe angle. The combined toe angle pertains to a combination of a wheel on the left side of the vehicle and a wheel on the right side of the vehicle, wherein both wheels of the combination have the same position as seen in the longitudinal direction, so e.g. both are front wheels or both are rear wheels.

If the wheels of a combination of wheels are arranged such that at the front of the wheels (as seen in the forward driving direction of the vehicle) the wheels are closer together than at the rear of the same wheels, this is called “toe-in”. This situation is shown in fig. 1. If the wheels of a combination of wheels are arranged such that at the front of the wheels (as seen in the forward driving direction of the vehicle) the wheels are closer together than at the rear of the same wheels, this is called “toe-out”. This situation is shown in fig. 2.

In general, if the right front wheel 3 has a toe angle a2 of x°, the left front wheel 2 has a toe angle a1 of -x°, and likewise, if the right rear wheel has a toe angle of y°, the left rear wheel has a toe angle of -y°. However, in some situations deviations from this general rule are possible, although such deviations may require a steering correction. If the right front wheel 3 has a toe angle a2 of x° and the left front wheel 2 has a toe angle a1 of -x°, the combined front toe angle a3 is 2x°. If the right rear wheel has a toe angle of y° and the left rear wheel has a toe angle of -y°, the combined rear toe angle is 2y°.

Fig. 3 shows, schematically, a first embodiment of an active toe angle adjustment system according to the first aspect of the invention, as applied in an electric vehicle.

The active toe angle adjustment system according to fig. 3 is adapted to control the toe angle a1 of first wheel 2 of the electric vehicle. The first wheel 2 is for example a front wheel of an electric vehicle, e.g. a left front wheel or a right front wheel of an electric vehicle, or a rear wheel of an electric vehicle, e.g. a left rear wheel or a right rear wheel of an electric vehicle.

In the example of fig. 3, the electric vehicle is provided with a traction battery 10, which is adapted to provide power to an electric propulsion system of the electric vehicle.

In the example of fig. 3. the electric vehicle is provided with an electric in-wheel motor 12, which is arranged to drive the first wheel 2. The traction battery 10 supplies electric power to the in-wheel motor 12 via electric feed line 11.

The active toe angle adjustment system as shown in fig. 3 comprises a first toe angle adjuster 20 which is adapted to adjust the toe angle of the first wheel 2 of the electric vehicle in which the active toe alignment system is arranged. The toe angle adjuster 20 is for example a dedicated toe angle adjuster. Alternatively, the toe angle adjuster 20 is partly or fully integrated in the steering system of the electric vehicle, e.g. in a steer-by wire steering system. Optionally, the first toe angle adjuster 20 comprises a steering rod length adjuster, which is adapted to adjust the length of a steering rod which extends between a left front wheel and a right front wheel.

The active toe angle adjustment system as shown in fig. 3 further comprises a power consumption measurement system, which is adapted to generate propulsion power measurement data relating to real time electric propulsion power consumption of the vehicle. In the embodiment of fig. 3, the power consumption measurement system comprises at least one sensor device 31 for measuring or otherwise determining a parameter value that is indicative and/or representative for the electric propulsion power consumption of the electric vehicle, either based on the parameter value as such or in combination with one or more other parameter values. The sensor device 31 comprises at least a sensor, optionally in combination with for example a local data processor and/or data transmission device for sending measurement data to a central processor 30 of the power consumption measurement system. The central processor 30 receives data from the sensor device 31 via data connection 32. Data connection 32 is for example a wired or wireless data connection.

Optionally, the power consumption measurement system comprises multiple sensor devices are arranged to measure or otherwise determine a parameter value that is indicative and/or representative for the electric propulsion power consumption of the electric vehicle at different locations within the electric vehicle.

Optionally, the power consumption measurement system comprises multiple sensor devices are arranged to measure or otherwise determine the parameter value of different parameters that are indicative and/or representative for the electric propulsion power consumption of the electric vehicle, either as such or in combination with other parameters.

Optionally, the power consumption measurement system comprises multiple sensor devices are arranged to measure or otherwise determine the parameter value of different parameters that are indicative and/or representative for the electric propulsion power consumption of the electric vehicle, which sensor devices are arranged at different locations within the electric vehicle.

In the embodiment of fig. 3, the sensor device 31 is adapted to measure electrical current. This sensor device 31 is arranged to measure the electrical current that is provided by the traction battery 10 of the electric vehicle in which the active toe angle adjustment system is arranged.

Alternatively or in addition, the sensor device 31 is adapted to measure voltage. The sensor device 31 is arranged to measure the voltage that is provided by the traction battery 10 of the electric vehicle in which the active toe angle adjustment system is arranged.

In the embodiment of fig. 3, the sensor device 31 is arranged to measure electrical current and/or voltage in the electric feed line 11 which provides electric power from the traction battery 10 to the in-wheel motor 12 of the first wheel 2.

This way, the sensor device 31 is adapted to measure a parameter value which is indicative of electric power consumption by the in-wheel motor 12 of the electric vehicle in which the active toe angle adjustment system is arranged. In the embodiment of fig. 3, the active toe angle adjustment system further comprises a toe angle controller 40 which is configured to:

- from the power consumption measurement system, during driving, obtain a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel 2 is at a first toe angle,

- during driving, instruct the first toe angle adjuster 20 to change the toe angle of the first wheel 2 to a second toe angle which is different from the first toe angle,

- from the power consumption measurement system, during driving, obtain a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel 2 is at the second toe angle,

- determining which toe angle is associated with the lowest electric propulsion power consumption,

- instruct the first toe angle adjuster 20 to arrange the first wheel 2 at the toe angle that is associated with the lowest electric propulsion power consumption.

The toe angle controller 40 is configured to, during driving, obtain a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel 2 is at a first toe angle from the power consumption measurement system.

The first power consumption data set comprises at least a datapoint relating to a measured or otherwise determined value of a parameter that is indicative for the consumed electric propulsion power at the time of generating the data set (’’real time”) and a datapoint pertaining to the value of the first toe angle. The data pertaining to the value of the first toe angle can for example be received from the power consumption measurement system, from the toe angle adjuster 20 or from a different source, e.g. from a vehicle control device. Electric propulsion power is the electric power that is used to propel the vehicle, e.g. the electric power to operate a central electric motor or one or more or all in-wheel motors of the electric vehicle.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set allows to establish or estimate how much electric power is consumed to propel the car. The parameter is for example measured instantaneously (i.e. at one discrete moment) or during a time period or over a certain distance travelled by the vehicle. Optionally, the first power consumption data set comprises processed values such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set. For example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is determined by measuring the amount of electric propulsion power that is required for keeping the vehicle at a constant velocity or by interrupting the supply of electric propulsion power to the vehicle, e.g. to the wheels of the vehicle, and determining the length of the time period that passes before the velocity of the vehicle is reduced by a certain amount or percentage (e.g. 2 km/h or 1%). Alternatively or in addition, for example the one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined during regenerative braking, e.g. by determining (e.g. measuring) the amount of power that is supplied to the battery by the regenerative braking system, optionally in combination with determining the reduction in velocity of the vehicle, e.g. during the time the power supply to the battery by the regenerative braking system is determined.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is for example electric power, an electric current, an electric voltage, a combination of an electric current and an electric voltage. Optionally, the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is not only indicative but also representative for the consumed electric propulsion power at the time of generating the data set.

The first power consumption data set is generated during driving, i.e. during normal operation of the vehicle, so that a vehicle-specific power consumption data set is generated. The value or values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set may depend on various driving condition parameters, e.g. velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. Optionally, parameter values indicative or representative for one or more of such driving condition parameters are also comprised in the first power consumption data set.

The toe angle controller 40 of fig. 3 is further configured to, during driving, instruct the first toe angle adjuster 20 to change the toe angle of the first wheel 2 to a second toe angle which is different from the first toe angle. The first toe angle adjuster 20 is connected to the toe angle controller 40 by a data connection 21 , e.g. a wired or wireless data connection. The data connection 21 allows the toe angle controller 40 to send instructions to the first toe angle adjuster 20. The difference between the first and the second toe angle is for example 0.1° - 1.5° (both mentioned values included), e.g. 0.25°- 1.0° (both mentioned values included), for example 0.5°. The toe angle controller of fig. 3 is further configured to, during driving, obtain from the power consumption measurement system a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel 2 is at the second toe angle.

The second power consumption data set comprises at least a datapoint relating to a measured or otherwise determined value of a parameter that is indicative for the consumed electric propulsion power at the time of generating the data set (’’real time”) and a datapoint pertaining to the value of the second toe angle.

The second power consumption data set optionally comprises at least parameter values of parameters that are comprised in the first data set so that comparison of data in the first power consumption data set and data in the second power consumption data set is possible.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set allows to establish or estimate how much electric power is consumed to propel the car. The parameter is for example measured instantaneously (i.e. at one discrete moment) or during a time period or during a predetermined distance travelled by the vehicle. Optionally, the second power consumption data set comprises processed values such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set.

For example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is determined by measuring the amount of electric propulsion power that is required for keeping the vehicle at a constant velocity or by interrupting the supply of electric propulsion power to the vehicle, e.g. to the wheels of the vehicle, and determining the length of the time period that passes before the velocity of the vehicle is reduced by a certain amount or percentage (e.g. 2 km/h or 1%). Alternatively or in addition, for example the one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined during regenerative braking, e.g. by determining (e.g. measuring) the amount of power that is supplied to the battery by the regenerative braking system, optionally in combination with determining the reduction in velocity of the vehicle, e.g. during the time the power supply to the battery by the regenerative braking system is determined.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is for example electric power, an electric current, an electric voltage, a combination of an electric current and an electric voltage. Optionally, the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is not only indicative but also representative for the consumed electric propulsion power at the time of generating the data set.

The second power consumption data set is generated during driving, i.e. during normal operation of the vehicle, so that a vehicle-specific power consumption data set is generated. The value or values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set may depend on various driving condition parameters, e.g. velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. Optionally, parameter values indicative or representative for one or more of such driving condition parameters are also comprised in the second power consumption data set.

The toe angle controller 40 of fig. 3 is further configured to determine which toe angle is associated with the lowest electric propulsion power consumption. This determination is carried out based on the first and second power consumption data sets, e.g. on the full power consumption data sets or on processed values in these power consumption data sets, such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set. For example, the average power consumption of the first power consumption data set and the average of the second power consumption data set are compared with each other.

The toe angle which is associated with the lowest electric propulsion power consumption can be for example be the first toe angle, the second toe angle or a toe angle that is different from the first and the second to angle. In the latter case, the toe angle that is associated with the lowest electric propulsion power consumption is determined by processing the first and second power consumption data set, e.g. based on further analysis of the power consumption datasets, which optionally includes a data analysis operation such as curve fitting. The toe angle which is associated with the lowest electric propulsion power consumption can be for example alternatively be determined on the basis of a straightforward comparison of the data in the first and second power consumption data sets.

In practical cases, this determination will be carried out during driving. However, alternatively it may be carried out at a stop, e.g. at the next stop, of the vehicle.

The toe angle controller 40 of fig. 3 is further configured to instruct the first toe angle adjuster 20 to arrange the first wheel 2 at the toe angle that is associated with the lowest electric propulsion power consumption. In practical cases, this instruction will be given during driving. However, alternatively it may be given at a stop, e.g. at the next stop, of the vehicle.

The embodiment of fig. 3 is suitable for carrying out the method according to the first aspect of the invention, for example for carrying out the method according to the first aspect of the invention in accordance with any of the described embodiments and/or in accordance with any combination of the described embodiments

Optionally, the first power consumption data set is obtained by receiving raw data from a measurement device, e.g. from the power consumption measurement system, and transforming the raw data into a first power consumption data set, e.g. by a processor of the toe angle controller 40. Alternatively or in addition, at least a part of the first power consumption data set or the entire first power consumption data set is received by the toe angle controller 40, e.g. from a power measurement device, for example from e.g. from the power consumption measurement system,.

Optionally, the second power consumption data set is obtained by receiving raw data from a measurement device, e.g. from the power consumption measurement system, and transforming the raw data into a second power consumption data set, e.g. by a processor of the toe angle controller 40. Alternatively or in addition, at least a part of the second power consumption data set or the entire second power consumption data set is received by the toe angle controller 40, e.g. from a measurement device for example from the power consumption measurement system.

Optionally, in the embodiment of fig. 3, the toe angle controller 40 is configured to, during driving:

- in determining which toe angle is associated with the lowest electric propulsion power consumption, comparing the first power consumption data set and the second power consumption data set with each other, and determining which power consumption data set indicates the lowest electric propulsion power consumption.

Optionally, in this embodiment, the first wheel 2 is arranged into the first or the second toe angle after determination which of these toe angles is associated with the lowest electric propulsion power consumption.

Optionally, in the embodiment of fig. 3, the toe angle controller 40 is configured to, during driving:

- instruct the first toe angle adjuster 20 to change the toe angle of the first wheel 2 to a further toe angle which is different from the first toe angle and from the second toe angle, - from the power consumption measurement system, obtain a further power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel 2 is at a further toe angle,

- in determining which toe angle is associated with the lowest electric propulsion power consumption, comparing at least one further power consumption data set with at least one of the first power consumption data set and the second power consumption data set and determining which of the first, second and further power consumption data sets indicates the lowest electric propulsion power consumption.

For example, first the first power consumption data set and the second power consumption data set are compared with each other, and it is determined which of these two power consumption data sets is associated with the lowest electric propulsion power consumption, and then that power consumption data set is compared to the further power consumption data set.

Optionally, the first wheel 2 is arranged into the first or the second toe angle or the further toe angle after determination which of these toe angles is associated with the lowest electric propulsion power consumption.

Optionally, in the embodiment of fig. 3, the toe angle controller 40 is configured to, during driving:

- instruct the first toe angle adjuster 20 to change the toe angle of the first wheel 2 to a further toe angle which is different from the first toe angle and from the second toe angle,

- from the power consumption measurement system, obtain a further power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel 2 is at a further toe angle,

- in determining which toe angle is associated with the lowest electric propulsion power consumption, determining a relation between the toe angle and the electric propulsion power consumption based on the generated power consumption data sets, e.g. through curve fitting, and selecting the toe angle that is associated with the lowest electric propulsion power consumption on the basis of this determined relation.

This may result in arranging the first wheel 2 at a toe angle which is different from the first, second and further toe angle, in case the determined relation between the toe angle and the electric propulsion power consumption shows that e.g. an intermediate toe angle provides a lower electric propulsion power consumption.

Optionally, the toe angle controller 40 is configured to additionally include comparing at least one further power consumption data set with at least one of the first power consumption data set and the second power consumption data set and determining which of the first, second and further power consumption data sets indicates the lowest electric propulsion power consumption in the step of determining which toe angle is associated with the lowest electric propulsion power consumption.

Optionally, in the embodiment of fig. 3, a further sensor device 50 and/or a data receiver 51 are provided. The further sensor device 50 is for example adapted to determine the value of a driving parameter. The date receiver 51 id adapted to receive data from an external source, e.g. from a website or other external data provider, and/or to receive data from an onboard system of the electric vehicle in which the active toe angle adjustment system is arranged, such as a navigation system.

Optionally, the toe angle controller 40 of the embodiment of fig. 3 is further configured to:

- receive data which pertains to a driving situation parameter value, e.g. from the further sensor device 50 and/or from the data receiver 51.

- on the basis of the driving situation parameter value, determining whether to initiate the determination which toe angle is associated with the lowest electric propulsion power consumption.

Optionally power consumption data sets are already generated before it is decided whether or not to determine which toe angle is associated with the lowest electric propulsion power consumption and to arrange the first wheel at the toe angle that is associated with the lowest electric propulsion power consumption.

Optionally the data pertaining to the driving parameter value includes one or more of:

- the velocity and/or changes in velocity and/or expected velocity and/or expected changes in velocity of the electric vehicle over a time period and/or distance, and/or

- based on navigation data, the expected amounts of steering actions for a coming time period and/or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination, and/or

- a vehicle vibration parameter, and/or

- a tire parameter, e.g. tire pressure and/or tire wear and/or tire type, and/or

- a weather related parameter.

In this embodiment, optionally the determination of the driving parameter value includes one or more of:

- determining the velocity and/or changes in velocity and/or expected velocity and/or expected changes in velocity of the electric vehicle over a time period or distance, and/or

- using navigation data, determining the expected amounts of steering actions for a coming time period or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination, and/or

- determining a vehicle vibration parameter, and/or - determining a tire parameter, e.g. tire pressure and/or tire wear and/or tire type,

- determining a weather related parameter.

Optionally, a score parameter value of a score parameter is determined which is based on multiple driving condition parameters values. Optionally, the score parameter value is based on weighted driving parameter values.

Optionally, the toe angle adjustment procedure is initiated only if a threshold value of a driving condition parameter or score parameter is exceeded.

Optionally, the steps of this embodiment are carried out at the start-up of the vehicle and/or when a destination is inputted in a navigation system and/or at a moment during driving when stable and/or constant driving conditions are expected.

Optionally, in the embodiment of fig. 3, the toe angle controller 40 is configured to:

- receive data which pertains to a driving situation parameter value,

- on the basis of the driving situation parameter value, determining whether to initiate obtaining a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel is at a first toe angle.

In this embodiment, it is first checked whether it is for example safe and useful to carry out an adjustment of the toe angle in order to obtain a low electric propulsion power consumption before actually initiating the toe angle adjustment procedure.

Optionally the data pertaining to the driving parameter value includes one or more of:

- the velocity and/or changes in velocity and/or expected velocity and/or expected changes in velocity of the electric vehicle over a time period and/or distance, and/or

- based on navigation data, the expected amounts of steering actions for a coming time period and/or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination, and/or

- a vehicle vibration parameter, and/or

- a tire parameter, e.g. tire pressure and/or tire wear and/or tire type, and/or

- a weather related parameter.

In this embodiment, optionally the determination of the driving parameter value includes one or more of:

- determining the velocity and/or changes in velocity and/or expected velocity and/or expected changes in velocity of the electric vehicle over a time period or distance, and/or

- using navigation data, determining the expected amounts of steering actions for a coming time period or distance and/or the expected type of roads to be travelled and/or the remaining distance to a set destination, and/or

- determining a vehicle vibration parameter, and/or

- determining a tire parameter, e.g. tire pressure and/or tire wear and/or tire type,

- determining a weather related parameter. Optionally, the further sensor device 50 is adapted to determine a value of a lateral acceleration parameter, and the toe angle controller 40 is further configured to, during driving:

- obtain a first lateral acceleration data set which is indicative for a real time lateral acceleration parameter value when the first wheel is at a first stability test toe angle,

- instruct the first toe angle adjuster 20 to change the toe angle of the first wheel 2 to a second stability test toe angle which is different from the first stability test toe angle,

- obtain a second lateral acceleration data set which is indicative for a real time lateral acceleration parameter value when the first wheel 2 is at the second stability test toe angle,

- determine which stability test toe angle is associated with the most advantageous value or values of the lateral acceleration parameter.

Optionally, the toe angle controller 40 is further configured to:

- instruct the first toe angle adjuster 20 to arrange the first wheel 2 at the stability test toe angle which is associated with the most advantageous value or values of the lateral acceleration parameter.

Optionally, the toe angle controller 40 is configured to monitor the lateral acceleration parameter during driving.

Optionally, the lateral acceleration parameter which exceeds a threshold value is the same as the parameter to which to real time lateral acceleration parameter value pertains. Alternatively, the lateral acceleration parameter which exceeds a threshold value is a different parameter than the parameter to which to real time lateral acceleration parameter value pertains.

Optionally, the first stability test toe angle is the toe angle at which the value of the lateral acceleration parameter exceeded the threshold value.

Optionally, the first stability test toe angle is the toe angle which is associated with the lowest electric propulsion power consumption, e.g. as determined in the method according to the first aspect of the invention.

Optionally, in this embodiment, the toe angle controller 40 is further configured to:

- during driving, changing the toe angle of the first wheel 2 to a further stability test toe angle which is different from the first stability test toe angle and from the second stability test toe angle, and generating a further lateral acceleration parameter data set which is indicative for the real time lateral acceleration parameter value when the first wheel 2 is at the further stability test toe angle, and optionally repeating this step for one or more additional mutually different further stability test toe angles of the first wheel 2 and therewith obtaining multiple further lateral acceleration parameter data sets, each lateral acceleration parameter data set being associated with a single further stability test toe angle. Optionally, in the embodiment of fig. 3, the toe angle controller 40 is further configured to:

- correct a generated power consumption data set for a driving condition that occurred during the generation of the power consumption data set.

For example, the toe angle controller 40 is configured to correct at least one a generated power consumption data set based on at least one driving condition parameter value, e.g. a value for vehicle velocity, average vehicle velocity over a time period or distance travelled by the vehicle, a weather-related parameter such as wind speed, wind direction relative to travel direction and/or atmospheric pressure, road conditions and/or tire pressure. Such a driving condition parameter may be obtained by the further sensor device 50 and/or by the data receiver 51.

Fig. 4 shows a variant of the embodiment of fig. 3. In this variant, the embodiment of fig. 3 is adapted for active toe angle control of two wheels.

In the variant of fig. 4, the system comprises not only a first toe angle adjuster 20 which is adapted to adjust the toe angle of the first wheel 2 of the electric vehicle in which the active toe alignment system is arranged, but also a second toe angle adjuster 22 which is adapted to adjust the toe angle of a second wheel 3 of the electric vehicle in which the active toe alignment system is arranged. The second toe angle adjuster 22 is connected to the toe angle controller 40 by a data connection 23, e.g. a wired or wireless data connection. The data connection 23 allows the toe angle controller 40 to send instructions to the second toe angle adjuster 22.

The second wheel 3 is a front wheel if the first wheel 2 is a front wheel and the second wheel 3 is a rear wheel if the first wheel 2 is a rear wheel. In the variant of fig. 4, the second wheel 3 is provided with an electric in-wheel motor 14. Electric feed line 13 which provides electric power from the traction battery 10 to the in-wheel motor 14 of the second wheel 3.

The second toe angle adjuster 22 is the same as or similar to the first toe angle adjuster 20, and may have all or some of the optional features that are described for the first toe angle controller 20 in relation to the embodiment of fig. 3.

In the variant of fig. 4, just like in the embodiment of fig. 3, a power consumption measurement system is provided which is adapted to generate propulsion power measurement data relating to real time electric propulsion power consumption of the vehicle.

Like in the embodiment of fig. 3, in the variant of fig. 4, the power consumption measurement system comprises at least one sensor device 31 for measuring or otherwise determining a parameter value that is indicative and/or representative for the electric propulsion power consumption of the electric vehicle, either based on the parameter value as such or in combination with one or more other parameter values. The sensor device 31 comprises at least a sensor, optionally in combination with for example a local data processor and/or data transmission device for sending measurement data to a central processor 30 of the power consumption measurement system. The central processor 30 receives data from the sensor device 31 via data connection 32. Data connection 32 is for example a wired or wireless data connection. The sensor device 31 and the data connection 32 in the variant of fig. 4 are the same as or similar to the sensor device 31 and the data connection 32 in the embodiment of fig. 3.

In addition, in the variant of fig. 4, the power consumption measurement system further comprises a second sensor device 34 for measuring or otherwise determining a parameter value that is indicative and/or representative for the electric propulsion power consumption of the electric vehicle, either based on the parameter value as such or in combination with one or more other parameter values. The second sensor device 34 comprises at least a sensor, optionally in combination with for example a local data processor and/or data transmission device for sending measurement data to a central processor 30 of the power consumption measurement system. The central processor 30 receives data from the sensor device 35 via data connection 35. Data connection 35 is for example a wired or wireless data connection.

In the variant of fig. 4, the second sensor device 34 is adapted to measure electrical current. This second sensor device 34 is arranged to measure the electrical current that is provided by the traction battery 10 of the electric vehicle in which the active toe angle adjustment system is arranged.

Alternatively or in addition, the second sensor device 34 is adapted to measure voltage. The second sensor device 34 is arranged to measure the voltage that is provided by the traction battery 10 of the electric vehicle in which the active toe angle adjustment system is arranged.

In the variant of fig. 4, the second sensor device 34 is arranged to measure electrical current and/or voltage in the electric feed line 13 which provides electric power from the traction battery 10 to the in-wheel motor 14 of the second wheel 3.

This way, the second sensor device 34 is adapted to measure a parameter value which is indicative of electric power consumption by the in-wheel motor 14 of the electric vehicle in which the active toe angle adjustment system is arranged.

The combined measured parameter values of sensor device 31 and second sensor device 34 together are indicative of electric power consumption by the in-wheel motors 12,14 and therewith of the electric power consumption by the electric vehicle as a whole.

In the variant of fig. 4, the toe angle controller 40 is configured to: - from the power consumption measurement system, during driving obtain a first power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel 2 is at a first toe angle and the second wheel 3 is at a first additional toe angle,

- during driving, instruct the first toe angle adjuster 20 to change the toe angle of the first wheel 2 to a second toe angle which is different from the first toe angle,

- during driving, instruct the second toe angle adjuster 22 to change the toe angle of the second wheel 3 to a second additional toe angle which is different from the first additional toe angle,

- from the power consumption measurement system, during driving, obtain a second power consumption data set which is indicative for real time electric propulsion power consumption when the first wheel 2 is at the second toe angle and the second wheel 3 is at a second additional toe angle,

- determine combination of toe angle of the first wheel 2 and additional toe angle of the second wheel 3 is associated with the lowest electric propulsion power consumption,

- instruct the first toe angle adjuster 20 to arrange the first wheel 2 at the toe angle that is associated with the lowest electric propulsion power consumption, and

- instruct the second toe angle adjuster 22 to arrange the second wheel 3 at the additional toe angle that is associated with the lowest electric propulsion power consumption.

In the variant of fig. 4, the toe angle of the first wheel 2 and the toe angle of a second wheel 3 are taken into consideration simultaneously. lin the variant of fig. 4, the first toe angle of the first wheel 2 is combined with a first additional toe angle of a second wheel 3 when generating the first power consumption data set. The first power consumption data set is indicative for real time electric propulsion power consumption when the first wheel 2 is at the first toe angle and the second wheel 3 is at the first additional toe angle.

Alternatively or in addition, in the variant of fig. 4, the second toe angle of the first wheel 2 is combined with a second additional toe angle of the second wheel 3 when generating the second power consumption data set. The second power consumption data set is indicative for real time electric propulsion power consumption when the first wheel 2 is at the second toe angle and the second wheel 3 is at the second additional toe angle.

Alternatively or in addition, in the variant of fig. 4, at least one further toe angle of the first wheel 2 is combined with a further additional toe angle of a second wheel 3 when generating the further power consumption data set. The respective further power consumption data set is indicative for real time electric propulsion power consumption when the first wheel 2 is at the at least one further toe angle and the second wheel 3 is at the further additional toe angle.

In the variant of fig. 4, the toe angle of e.g. the left front wheel and the right front wheel, and/or the left rear wheel and the right rear wheel are considered in combination with each other when generating art least one, an optionally multiple or all, power consumption data set(s). This is likely to provide a more accurate outcome of the determination of the optimal setting of the toe angle and additional toe angle in order to obtain the lowest electric propulsion power consumption.

In the variant of fig. 4, the toe angle controller 40 is configured to instruct the second toe angle adjuster 22 to arrange the second wheel 3 at the additional toe angle that is associated with the lowest electric propulsion power consumption. So, in this case, the combination of the toe angle of the first wheel 2 and additional toe angle of the second wheel 3 that is associated with the lowest electric propulsion power consumption is determined, and the first wheel 2 is arranged at the toe angle associated with this combination and the second wheel 3 is arranged at the additional toe angle that is associated with this same combination. For example, the first wheel 2 is arranged at the first toe angle and the second wheel 3 is arranged at the first additional toe angle if it turns out that the combination of the first toe angle and the first additional toe angle is associated with the lowest electric propulsion power consumption, or the first wheel 2 is arranged at the second toe angle and the second wheel 3 is arranged at the second additional toe angle if it turns out that the combination of the second toe angle and the second additional toe angle is associated with the lowest electric propulsion power consumption, or the first wheel 2 is arranged at a further toe angle and the second wheel 3 is arranged at the further additional toe angle that is associated with this particular further toe angle if it turns out that the combination of the further toe angle and the associated further additional toe angle is associated with the lowest electric propulsion power consumption.

In the variant of fig. 4, optionally the first toe angle and the first additional toe angle have the same value but are opposite in direction. For example, the first toe angle is 0.5°and the first additional toe angle is -0.5°. Alternatively, optionally the first toe angle and the first additional toe angle do not have the same value but still are opposite in direction. For example, the first toe angle is 0.45°and the first additional toe angle is -0.55°. This may occur e.g. due to a different wear pattern in the left and right tire. In this case, additional steering corrections may be required. Likewise, optionally the second toe angle and the second additional toe angle have the same value but are opposite in direction. For example, the second toe angle is 0.5°and the second additional toe angle is -0.5°. Alternatively, optionally the second toe angle and the second additional toe angle do not have the same value but still are opposite in direction. For example, the second toe angle is 0.45°and the second additional toe angle is -0.55°.

Likewise, optionally the further toe angle and the further additional toe angle have the same value but are opposite in direction. For example, the further toe angle is 0.5°and the further additional toe angle is -0.5°. Alternatively, optionally the further toe angle and the further additional toe angle do not have the same value but still are opposite in direction. For example, the further toe angle is 0.45°and the further additional toe angle is -0.55°.

In a variant of this active toe angle adjustment system, the first toe angle of the first wheel 2 is combined with a first additional toe angle of a second wheel 3 when generating the first power consumption data set, and the second toe angle of the first wheel 2 is combined with a second additional toe angle of a second wheel 3 when generating the second power consumption data set, and at least one further toe angle of the first wheel 2 is combined with a further additional toe angle of a second wheel 3 when generating the further power consumption data set. In this variant, optionally, the first toe angle is the same as the second toe angle, and the first additional toe angle is different from the second additional toe angle, and the further toe angle is different from the first toe angle and from the second toe angle, and the further additional toe angle is the same as either the first additional toe angle or the second additional toe angle.

Optionally, in the variant of fig. 4, the further sensor device 50 is adapted to determine a value of a lateral acceleration parameter, and the toe angle controller 40 is further configured to, during driving:

- obtain a first lateral acceleration data set which is indicative for a real time lateral acceleration parameter value when the first wheel is at a first stability test toe angle,

- instruct the first toe angle adjuster 20 to change the toe angle of the first wheel 2 to a second stability test toe angle which is different from the first stability test toe angle,

- obtain a second lateral acceleration data set which is indicative for a real time lateral acceleration parameter value when the first wheel 2 is at the second stability test toe angle,

- determine which stability test toe angle is associated with the most advantageous value or values of the lateral acceleration parameter.

Optionally, the toe angle controller 40 is further configured to:

- instruct the first toe angle adjuster 20 to arrange the first wheel 2 at the stability test toe angle which is associated with the most advantageous value or values of the lateral acceleration parameter. Optionally, the first stability test toe angle of the first wheel 2 is combined with a first additional stability test toe angle of a second wheel 3 when generating the lateral acceleration parameter data. The first lateral acceleration parameter data is indicative for the real time lateral acceleration parameter value when the first wheel 2 is at the first stability test toe angle and the second wheel 3 is at the first stability test additional toe angle.

Alternatively or in addition, the second stability test toe angle of the first wheel 2 is combined with a second additional stability test toe angle of a second wheel 3 when generating the second lateral acceleration parameter data. The second lateral acceleration parameter data is indicative for the real time lateral acceleration parameter value when the first wheel 2 is at the second stability test toe angle and the second wheel 3 is at the second additional stability test toe angle.

Alternatively or in addition, at least one further stability test toe angle of the first wheel is combined with a further additional stability test toe angle of a second wheel when generating the further lateral acceleration parameter data. The respective further lateral acceleration parameter data is indicative for the real time lateral acceleration parameter value when the first wheel 2 is at the at least one further stability test toe angle and the second wheel 3 is at the further additional stability test toe angle.

Optionally, in the variant of fig. 4, the toe angle controller 40 is configured to, after determining which stability test toe angle is associated with the most advantageous value or values of the lateral acceleration parameter, instruct the first toe angle adjuster 20 to bring the first wheel 2 into a toe angle that corresponds to this stability test toe angle and instruct the second toe angle adjuster 22 to bring the second wheel 3 into the additional stability test toe angle that is associated with this stability test toe angle.

Optionally, the toe angle controller 40 is configured to, after instructing the first toe angle adjuster to bring the first wheel in the stability test toe angle which is associated with the most advantageous value or values of the lateral acceleration parameter, monitor the lateral acceleration parameter of the electric vehicle, and in case a value of the lateral acceleration parameter remains below a threshold value, and to instruct the first toe angle adjuster to bring back the first wheel, to a vehicle efficiency toe angle. Optionally, the monitoring takes place during a predetermined time period or distance travelled by the vehicle.

A vehicle efficiency toe angle is a toe angle which is selected on the basis of an advantageous level of electric propulsion power consumption.

Optionally, the vehicle efficiency toe angle is the toe angle that is associated with lowest electric propulsion power consumption, e.g. the toe angle that is associated with the lowest electric propulsion power consumption as determined in accordance with the first aspect of the invention.

Fig. 5, fig. 6 and fig. 7 show, schematically, subsequent steps in an embodiment of the method according to the first aspect of the invention. This embodiment of the method according to the first aspect of the invention is illustrated using the variant of fig. 4.

For example, the first wheel 2 in fig. 5, fig. 6 and fig. 7 is a left front wheel and the second wheel 3 in in fig. 5, fig. 6 and fig. 7 is a right front wheel.

Fig. 5 shows a first stage of the embodiment of the method according to the first aspect of the invention.

In this first stage, the first wheel 1 is arranged at a first toe angle a1-1 , and the second wheel is arranged at a first additional toe angle a2-1. The toe angle and the additional toe angle are, respectively, the angle between the respective wheel 2, 3 (as represented by the respective lines 5 in fig. 5) and the line 6, which line 6 is parallel to the longitudinal direction of the vehicle when the vehicle is driving straight ahead.

In the example of fig 5, the first toe angle a1-1 and the first additional toe angle a2-1 are the same in value, but opposite in direction.

With the first wheel 2 arranged at the first toe angle a1-1 and the second wheel 3 at the additional first toe angle a2-1, during driving, a first power consumption data set which is indicative for real time electric propulsion power consumption is generated. The first power consumption data set is in this embodiment indicative for real time electric propulsion power consumption when the first wheel 2 is at the first toe angle a1-1 and the second wheel 3 is at the first additional toe angle a2-1.

The first power consumption data set comprises at least a datapoint relating to a measured or otherwise determined value of a parameter that is indicative for the consumed electric propulsion power at the time of generating the data set (’’real time”) and a datapoint pertaining to the value of the first toe angle. Electric propulsion power is the electric power that is used to propel the vehicle, e.g. the electric power to operate a central electric motor or one or more or all in-wheel motors of the electric vehicle.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set allows to establish or estimate how much electric power is consumed to propel the car. The parameter is for example measured instantaneously (i.e. at one discrete moment) or during a time period or over a certain distance travelled by the vehicle. Optionally, the first power consumption data set comprises one or more processed values, e.g. values calculated from measured data, such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set.

For example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined by measuring the amount of electric propulsion power that is required for keeping the vehicle at a constant velocity or by interrupting the supply of electric propulsion power to the vehicle, e.g. to the wheels of the vehicle, and determining the length of the time period that passes before the velocity of the vehicle is reduced by a certain amount or percentage (e.g. 2 km/h or 1%). Alternatively or in addition, for example the one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined during regenerative braking, e.g. by determining (e.g. measuring) the amount of power that is supplied to the battery by the regenerative braking system, optionally in combination with determining the reduction in velocity of the vehicle, e.g. during the time the power supply to the battery by the regenerative braking system is determined.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is for example electric power, an electric current, an electric voltage, a combination of an electric current and an electric voltage. Optionally, the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is not only indicative but also representative for the consumed electric propulsion power at the time of generating the data set.

Optionally, the first power consumption data set is stored in a computer memory, e.g. in a vehicle-specific database. The vehicle-specific database contains information about the specific, individual vehicle for which the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set has been generated.

The first power consumption data set is generated during driving, i.e. during normal operation of the vehicle, so that a vehicle-specific power consumption data set is generated. The value or values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set may depend on various driving condition parameters, e.g. velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. Optionally, parameter values indicative or representative for one or more of such driving condition parameters are also comprised in the first power consumption data set. The method may be initiated by the driver or by a vehicle control system. In a second, subsequent step of the embodiment of the method according to the first aspect of the invention, during driving, the toe angle of the first wheel 2 is changed to a second toe angle a1-2 which is different from the first toe angle a1-2, and the additional toe angle of the second wheel 3 is changed to a second additional toe angle a2-2 which is different from the first additional toe angle a2-1. This situation is shown in fig. 6.

The difference between the first toe angle a1-1 and the second toe angle a1 -2 is for example 0.1° - 1.5° (both mentioned values included), e.g. 0.25°- 1.0° (both mentioned values included), for example 0.5°. The difference between the first additional toe angle a2-1 and the second additional toe angle a2-2 is for example 0.1° - 1.5° (both mentioned values included), e.g. 0.25°- 1.0° (both mentioned values included), for example 0.5°.

With the first wheel 2 arranged at the second toe angle c -2 and the second wheel 3 at the second additional toe angle a2-2, during driving, a second power consumption data set which is indicative for real time electric propulsion power consumption is generated. The second power consumption data set is in this embodiment indicative for real time electric propulsion power consumption when the first wheel 2 is at the second toe angle cd -2 and the second wheel 3 is at the second additional toe angle a2-2.

The second power consumption data set comprises at least a datapoint relating to a measured or otherwise determined value of a parameter that is indicative for the consumed electric propulsion power at the time of generating the data set (’’real time”) and a datapoint pertaining to the value of the second toe angle.

The second power consumption data set optionally comprises at least parameter values of parameters that are comprised in the first data set so that comparison of data in the first power consumption data set and data in the second power consumption data set is possible.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set allows to establish or estimate how much electric power is consumed to propel the car. The parameter is for example measured instantaneously (i.e. at one discrete moment) or during a time period or during a predetermined distance travelled by the vehicle. Optionally, the second power consumption data set comprises one or more processed values, e.g. values calculated from measured data, such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the second power consumption data set. For example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is determined by measuring the amount of electric propulsion power that is required for keeping the vehicle at a constant velocity or by interrupting the supply of electric propulsion power to the vehicle, e.g. to the wheels of the vehicle, and determining the length of the time period that passes before the velocity of the vehicle is reduced by a certain amount or percentage (e.g. 2 km/h or 1%). Alternatively or in addition, for example the one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined during regenerative braking, e.g. by determining (e.g. measuring) the amount of power that is supplied to the battery by the regenerative braking system, optionally in combination with determining the reduction in velocity of the vehicle, e.g. during the time the power supply to the battery by the regenerative braking system is determined.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is for example electric power, an electric current, an electric voltage, a combination of an electric current and an electric voltage. Optionally, the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is not only indicative but also representative for the consumed electric propulsion power at the time of generating the data set.

Optionally, the second power consumption data set is stored in a computer memory, e.g. in a vehicle-specific database. The vehicle-specific database contains information about the specific, individual vehicle for which the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set has been generated.

The second power consumption data set is generated during driving, i.e. during normal operation of the vehicle, so that a vehicle-specific power consumption data set is generated. The value or values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set may depend on various driving condition parameters, e.g. velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. Optionally, parameter values indicative or representative for one or more of such driving condition parameters are also comprised in the second power consumption data set.

In a third, subsequent step of the embodiment of the method according to the first aspect of the invention, during driving, the toe angle of the first wheel 2 is changed to a further toe angle a1 -3 which is different from the first toe angle cd-1 and from the second toe angle a1-2, and the additional toe angle of the second wheel 3 is changed to a further additional toe angle a2-3 which is different from the first additional toe angle a2-1 and from the second additional toe angle a2-2. This situation is shown in fig. 7.

The difference between the second toe angle a1 -2 and the further toe angle c -3 is for example 0.1° - 1.5° (both mentioned values included), e.g. 0.25°- 1.0° (both mentioned values included), for example 0.5°. The difference between the second additional toe angle a2-2 and the further additional toe angle a2-3 is for example 0.1° - 1.5° (both mentioned values included), e.g. 0.25°- 1.0° (both mentioned values included), for example 0.5°.

With the first wheel 2 arranged at the further toe angle cd -3 and the second wheel 3 at the further additional toe angle a2-3, during driving, a further power consumption data set which is indicative for real time electric propulsion power consumption is generated. The further power consumption data set is in this embodiment indicative for real time electric propulsion power consumption when the first wheel 2 is at the further toe angle cd-3 and the second wheel 3 is at the further additional toe angle a2-3.

The further power consumption data set comprises at least a datapoint relating to a measured or otherwise determined value of a parameter that is indicative for the consumed electric propulsion power at the time of generating the data set (’’real time”) and a datapoint pertaining to the value of the further toe angle.

The further power consumption data set optionally comprises at least parameter values of parameters that are comprised in the first data set so that comparison of data in the first power consumption data set and data in the further power consumption data set is possible.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set allows to establish or estimate how much electric power is consumed to propel the car. The parameter is for example measured instantaneously (i.e. at one discrete moment) or during a time period or during a predetermined distance travelled by the vehicle. Optionally, the further power consumption data set comprises one or more processed values, e.g. values calculated from measured data, such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the further power consumption data set.

For example, one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is determined by measuring the amount of electric propulsion power that is required for keeping the vehicle at a constant velocity or by interrupting the supply of electric propulsion power to the vehicle, e.g. to the wheels of the vehicle, and determining the length of the time period that passes before the velocity of the vehicle is reduced by a certain amount or percentage (e.g. 2 km/h or 1%). Alternatively or in addition, for example the one or more values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the first power consumption data set is determined during regenerative braking, e.g. by determining (e.g. measuring) the amount of power that is supplied to the battery by the regenerative braking system, optionally in combination with determining the reduction in velocity of the vehicle, e.g. during the time the power supply to the battery by the regenerative braking system is determined.

The parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is for example electric power, an electric current, an electric voltage, a combination of an electric current and an electric voltage. Optionally, the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set is not only indicative but also representative for the consumed electric propulsion power at the time of generating the data set.

Optionally, the further power consumption data set is stored in a computer memory, e.g. in a vehicle-specific database. The vehicle-specific database contains information about the specific, individual vehicle for which the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set has been generated.

The further power consumption data set is generated during driving, i.e. during normal operation of the vehicle, so that a vehicle-specific power consumption data set is generated. The value or values of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set may depend on various driving condition parameters, e.g. velocity of the vehicle, type of road the vehicle is driving on, wind speed, angle of the driving direction relative to the wind, wet, dry or icy surface, tire type, tire pressure and/or tire wear. Optionally, parameter values indicative or representative for one or more of such driving condition parameters are also comprised in the further power consumption data set.

In a further subsequent step of this embodiment of the method according to the first aspect of the invention, it is determined which combination of toe angle and additional toe angle is associated with the lowest electric propulsion power consumption. This step is carried out based on the first, second and further power consumption data sets, e.g. on the full power consumption data sets or on processed values in these power consumption data sets, such as an average value, a median value, a minimum value, and/or a maximum value of the parameter that is indicative for the consumed electric propulsion power at the time of generating the data set. For example, the average power consumption of the first power consumption data set and the average of the second power consumption data set and the average of the further power consumption data set are compared with each other.

In practical cases, this step will be carried out during driving. However, alternatively it may be carried out at a stop, e.g. the next stop, of the vehicle.

The toe angle which is associated with the lowest electric propulsion power consumption can be for example be the first toe angle, the second toe angle, the further toe angle or a toe angle that is different from the first and the second to angle. In the latter case, the toe angle that is associated with the lowest electric propulsion power consumption is determined by processing the first and second power consumption data set, e.g. based on further analysis of the power consumption datasets, which optionally includes a data analysis operation such as curve fitting. The toe angle which is associated with the lowest electric propulsion power consumption can be for example alternatively be determined on the basis of a straightforward comparison of the data in the first and second power consumption data sets.

In a further subsequent step of this embodiment of the method according to the first aspect of the invention, the first wheel 2 of the electric vehicle is arranged at the toe angle of the combination of toe angle and additional toe angle that is associated with the lowest electric propulsion power consumption and the second wheel 3 of the electric vehicle is arranged at the additional toe angle of the combination of toe angle and additional toe angle that is associated with the lowest electric propulsion power consumption.