CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application Ser. No. 63/349,451, filed on June 6, 2022, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] Off-highway machines/vehicles can include one or more functions that may be hydraulically controlled.

BRIEF SUMMARY

[0003] In one aspect, the present disclosure provides a hydraulic control system for maximizing system efficiency. The hydraulic control system includes a plurality pumps, a plurality of consumers selectively fluidically coupled to the plurality of pumps, and a controller in communication with the plurality of pumps and the plurality of consumers In one example, the controller may be configured to group one or more of the plurality of pumps with one or more of the plurality of consumers based on at least one of a pressure and a flow rate of the consumer.

[0004] According one aspect of the disclosure, a hydraulic control system is provided. The hydraulic control system can include a plurality of pumps and a plurality of consumers selectively fluidly coupled to the plurality of pumps. A controller can be in communication with the plurality of pumps and the plurality of consumers. The controller can be configured to group one or more of the plurality of pumps with one or more of the plurality of consumers based on at least one of a pressure and a flow rate of the one or more of the plurality of consumers.

[0005] In some non-limiting examples, at least one of the plurality of pumps can be a radial piston style variable flow pump. The radial piston style variable flow pump can include a pump inlet and an inlet throttling flow control device. The inlet throttling flow control device can be configured to restrict flow from the inlet into the pump. In some cases, the inlet throttling flow control device can be a hydro-mechanical inlet pressure compensator.

[0006] In some non-limiting examples, one or more flow control devices can be fluidly coupled between one or more of the plurality of pumps and one or more of the plurality of consumers to regulate flow between the pumps and the consumers. The controller can adjust a position of the one or more flow control devices in response to an input from a control device. In some cases, the control device can include a joystick configured to control an off-highway vehicle. [0007] In some non-limiting examples, the hydraulic control system can further include at least one of a sensor arranged adjacent the plurality of pumps and a sensor arranged adjacent the plurality of consumers. The controller can be configured to monitor a status of the sensor.

[0008] In some non-limiting examples, the controller can be configured to group two or more pumps with a single consumer when a demanded a flow rate of a consumer can be greater than a single pump can provide. In some non-limiting examples, the controller can be configured to group a single pump to more than one consumer when a single pump meets a demanded flow rate of the more than one consumer. In some cases, the controller can determine a pump pressure setpoint for one or more of the plurality of pumps based on a pressure demanded by one or more of the plurality of consumers.

[0009] According another aspect of the disclosure, a method for controlling a hydraulic system is provided. With a controller, a pressure demanded by each of a plurality of consumers can be determined. The plurality of consumers can be grouped into one or more groups based on a predetermined pressure range. A total flow rate demanded by each group can be determined and one or more of a plurality of pumps can be assigned to each group based of an available flow rate of the pumps and the total flow rate demanded by the groups. With the one or more of the plurality of pumps, at least a portion of the demanded flow rate can be supplied at the demanded pressure to each consumer within the groups.

[0010] In some non-limiting examples, with the controller, one or more of the plurality of pumps can be matched with the groups based on a pressure setpoint of the group. The pressure setpoint of the group can be the highest pressure demanded by a consumer within the group. In some cases, the predetermined pressure range for each group can be 50 bar.

[0011] In some non-limiting examples, the controller can determine if each consumer within each group received the total flow rate demanded. With one or more pumps, an additional flow rate can be supplied at an unmatched pressure to one or more of the plurality of consumers that did not receive the total flow rate demanded. For example, one or more of a plurality of flow control devices can compensate flow from one or more of the plurality of pumps at a higher pressure to fulfil the additional flow rate demanded by one or more of the plurality of consumers at a lower pressure. In some cases, if the additional flow rate demanded by one or more of the plurality of consumers is at a pressure higher than an available pump pressure no additional flow rate can be provided to the one or more of the plurality of consumers. In some cases, the additional flow rate can be provided if a difference between the pressure demanded by one or more of the plurality of consumers and an available pump pressure can be within a predetermined efficiency band. [0012] In some non-limiting examples, the controller can receive an input command from a control device and information from one or more sensors positioned adjacent the consumers. The controller can determine the demanded pressure and flow rate based on information received from the control device and the one or more sensors.

[0013] In some non-limiting examples, at least one of the plurality of pumps can be a radial piston sty le variable flow pump. The radial piston style variable flow pump can include a pump inlet, and an inlet throttling flow control device. The inlet throttling flow control device can be configured to restrict flow from the inlet into the pump. In some cases, the inlet throttling flow control device can be a hydro-mechanical inlet pressure compensator.

[0014] The foregoing and other aspects and advantages of the disclosure will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by way of illustration a preferred configuration of the disclosure. Such configuration does not necessarily represent the full scope of the disclosure, however, and reference is made therefore to the claims and herein for interpreting the scope of the disclosure.

BRIEF DESCRIPTION OF DRAWINGS

[0015] The invention will be better understood and features, aspects and advantages other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such detailed description makes reference to the following drawings.

[0016] FIG. 1 is a schematic view of an example of a hydraulic circuit according to aspects of the present disclosure.

[0017] FIG. 2 is a schematic view of an example of a hydraulic control system including the hydraulic circuit of FIG. 1.

[0018] FIG. 3A is a flowchart showing an example pump allocation process for use with the hydraulic control system of FIG. 2.

[0019] FIG. 3B is a flowchart showing a consumer flow allocation process of the pump allocation process of FIG. 3 A.

[0020] FIG. 4 is a table showing an example pump allocation for the hydraulic control system of FIG. 2.

[0021] FIG. 5 is a table showing an example pump allocation for the hydraulic control system of FIG. 2.

[0022] FIG. 6 is a table showing an example pump allocation for the hydraulic control system of FIG. 2. [0023] FIG. 7 is a table showing an example pump allocation for the hydraulic control system of FIG. 2.

[0024] FIG. 8 is a table showing an example pump allocation for the hydraulic control system of FIG. 2.

[0025] FIG. 9 is a table showing an example pump allocation for the hydraulic control system of FIG. 2.

[0026] FIG. 10 is a table showing an example pump allocation for the hydraulic control system of FIG. 2.

[0027] FIG. 11 is a table showing an example pump allocation for the hydraulic control system of FIG. 2.

[0028] FIG. 12 is a table showing an example pump allocation for the hydraulic control system of FIG. 2.

[0029] FIG. 13 is a table showing an example pump allocation for an off-highway vehicle using the hydraulic control system of FIG. 2.

[0030] FIG. 14 is a table showing an example pump allocation for an off-highway vehicle using the hydraulic control system of FIG. 2.

[0031] FIG. 15 is a table showing an example pump allocation for an off-highway vehicle using the hydraulic control system of FIG. 2.

[0032] FIG. 16 is a table showing an example pump allocation for an off-highway vehicle using the hydraulic control system of FIG. 2.

[0033] FIG. 17 is a table showing an example pump allocation for an off-highway vehicle using the hydraulic control system of FIG. 2.

DETAILED DESCRIPTION

[0034] Before any aspect of the present disclosure are explained in detail, it is to be understood that the present disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The present disclosure is capable of other configurations and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the temis “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings and may also indicate fluid couplings.

[0035] The following discussion is presented to enable a person skilled in the art to make and use aspects of the present disclosure. Various modifications to the illustrated configurations will be readily apparent to those skilled in the art, and the generic principles herein can be applied to other configurations and applications without departing from aspects of the present disclosure. Thus, aspects of the present disclosure are not intended to be limited to configurations shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein. The following detailed description is to be read with reference to the figures, in which like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected configurations and are not intended to limit the scope of the present disclosure. Skilled artisans will recognize the non-limiting examples provided herein have many useful alternatives and fall within the scope of the present disclosure.

[0036] The reference numerals in the following description have been organized to aid the reader in quickly identifying the drawings where various components are first shown. In particular, the drawing in which an element first appears is typically indicated by the left-most digit(s) in the corresponding reference number. For example, an element identified by a “hydraulic circuit 100” series reference numeral will likely first appear in FIG. 1, an element identified by a “hydraulic control system 200” series reference numeral will likely first appear in FIG. 2, and so on.

[0037] The use of the terms “downstream” and “upstream” herein are terms that indicate direction relative to the flow of a fluid. The term “downstream” corresponds to the direction of fluid flow, while the term “upstream” refers to the direction opposite or against the direction of fluid flow.

[0038] Generally, the present disclosure provides hydraulic control systems and methods configured to optimize overall system efficiency. In one example, one or more pumps (e.g., radial piston pumps) may be fluidically coupled to one or more consumers (e.g., actuators, motors, and/or other hydraulic components), which may be used to effectuate one or more functions of an off-highway vehicle. The pumps may be configured to supply a particular flow rate and/or hydraulic pressure to the one or more consumers based on one or more inputs. In one example, the system may include a controller in communication with the one or more pumps and/or the one or more consumers. In one example, the controller may receive the inputs and determine a pump pressure (e.g., high pressure, medium pressure, low pressure) and/or flow rate demanded by the consumer. In another example, the controller may match the pump pressure with a pressure demanded by the consumer. Put differently, the controller may group and/or link similar pressure pumps and consumers to increase overall system efficiency.

[0039] In one example, matching pump and consumer pressures can mitigate the need for compensating (e.g., reducing via one or more flow control devices) hydraulic fluid pressure, which can increase overall system efficiency and reduce system losses. For example, low pressure pumps may supply consumers demanding low pressure hydraulic fluid, medium pressure pumps may supply consumers demanding medium pressure hydraulic fluid, and high- pressure pumps may supply consumers demanding high pressure hydraulic fluid. In one example, a single pump may provide flow (e.g., hydraulic fluid at a predetermined pressure) to more than one consumer (e.g., two consumers, three consumers, four consumers, and/or more consumers). In another example, two or more pumps may provide flow (e.g., hydraulic fluid at a predetermined pressure) to a single consumer. In one example, one or more flow control devices (e.g., valves, regulators, etc.) may be configured to control the flow of hydraulic fluid from the pumps to the consumers. For example, the controller may communicate with the flow control devices to enable, disable, and/or compensate flow from the pumps to the consumers in order to supply a predetermined flow rate at a predetermined pressure to the consumers.

[0040] FIG. 1 shows an example of a hydraulic circuit 100 including one or more pumps 102 fluidically connected to one or more consumers 122. In one example, the pumps 102 may be in the form of variable displacement radial piston style pumps. In other examples, the pumps 102 may be in the form of axial piston style pumps, load sense pumps, positive and/or negative flow control pumps, other style pumps, and/or any combination thereof. Additionally, the pumps 102 may be in the form of fixed displacement pumps, variable displacement pumps, and/or any combination thereof. In one particular example, the pumps 102 may be in the form of variable flow radial piston pumps with inlet throttling flow control as described in United States Patent No. 8,926,298 B2, filed on January 4, 2012, which is herein incorporated by reference in its entirety. In one example, the use of dimensionally smaller radial piston style pumps can allow for a greater number of pumps to be within the same housing and/or on a shared shaft and/or other prime movers. Thus, pumps may be allocated to consumers operating at the same and/or similar pressure values (e.g., high, medium, low pressures), which may reduce efficiency losses caused by compensation of pump pressures via one or more flow control devices within the hydraulic circuit 100. To that end, pumps can include a hydromechanical inlet pressure compensator to compensate the inlet throttling flow control for varying pump inlet pressures to maintain desired pump flow (e.g., to provide a desired pump flow over varying pump inlet conditions).

[0041] The consumers 122 may be in the form of any type of hydraulic device configured to receive hydraulic fluid from the pumps 102. In one example, the consumers 122 may be linked to one or more functions of the off-highway vehicle (e.g., digging, dumping, moving, etc.). In one example, the consumers 122 may be in the form of actuators (e.g., hydraulic actuators), cylinders, valves, reservoirs, motors, and/or other hydraulic components used to operate the function of the vehicle

[0042] As shown in FIG. 1, a single pump 102 may be connected to a single consumer 122 and/or to multiple consumers 122 via operation of one or more flow control devices 142. In one example, the flow control devices 142 may include valves, regulators, and/or other flow control devices. In one example, each consumer 122 may include a flow control array configured to control flow from the pumps f02 into the consumers f22. For example, a first consumer 125 may include a first flow control array 145, a second consumer 130 may include a second flow control array 150, a third consumer 135 may include a third flow control array 155, a fourth consumer 140 may include a fourth flow control array 160, and so on. Each flow control array may include one or more flow control devices 142 configured to enable, disable, and/or compensate flow from the pumps 102 to the consumers 122.

[0043] In one example, each pump 102 may include a corresponding flow control device in each of the flow control arrays. For example, a first pump 105 may include a first flow control device 165 in each of the first flow control array 145, the second flow control array 150, the third flow control array 155, and the fourth flow control array 160. A second pump 110 may include a second flow control device 170 in each of the first flow control array 145, the second flow control array 150, the third flow control array 155, and the fourth flow control array 160. A third pump 115 may include a third flow control device 175 in each of the first flow control array 145, the second flow control array 150, the third flow control array 155, and the fourth flow control array 160. A fourth pump 120 may include a fourth flow control device 180 in each of the first flow control array 145, the second flow control array 150, the third flow control array 155, and the fourth flow control array 160, and so on. Thus, each of the pumps 105, 110, 115, 120 may supply flow to each of the consumers 125, 130, 135, 140 via the corresponding flow control device in each of the respective flow control arrays.

[0044] Thus, in one example, the first pump 105 may provide hydraulic fluid at a predetermined pressure and/or flow rate to any and/or all of the first consumer 125, the second consumer 130, the third consumer 135, and the fourth consumer 140 via the first flow control device 165 in each of the first flow control array 145, the second flow control array 150, the third flow control array 155, and the fourth flow control array 160. Similar principles are applicable to each of the second pump 110, the third pump 115, and the fourth pump 120 in accordance with the respective flow control devices 170, 175, 180 in each of the first flow control array 145, the second flow control array 150, the third flow control array 155, and the fourth flow control array 160.

[0045] To that end, it is possible for any single pump or combination of pumps to supply fluid to any single consumer or combination of consumers For example, each of the first pump 105, the second pump 110, the third pump 115, and the fourth pump 120 may provide hydraulic fluid at a predetermined pressure to only the first consumer 125 via the first flow control device 165, the second flow control device 170, the third flow control device 175, and the fourth flow control device 180 of the first flow control array 145, respectively.

[0046] This configuration enables the pumps 102 to supply hydraulic fluid to the consumers 122 via the flow control devices 142 in a variety of configurations to efficiently supply hydraulic fluid at a desired flow rate and/or pressure, with minimal need to compensate pressures (via the flow control devices) from the pumps 102. As should be appreciated, the example shown in FIG. 1 is merely an example of a hydraulic circuit 100 and hydraulic circuits with more and/or less pumps 102, consumers 122, and/or flow control devices 142 are envisioned.

[0047] FIG. 2 illustrates an example of a hydraulic control system 200 for use with the hydraulic circuit 100. In one example, the hydraulic control system 200 includes a controller 210, such as a controller configured to receive an electronic and/or hydraulic input 205. In one example, the input 205 may include feedback from an operator (e.g., movement of a joystick, actuation of a lever, press of a button, or other user input device, etc.) and/or feedback from an autonomous control system. The controller 210 may additionally receive information from one or more sensors 215. The sensors 215 may monitor one or more conditions of a hydraulic machine (e.g., vehicle and/or function position, velocity, pressure, pump inlet and/or outlet pressures, temperature, and/or other conditions). Thus, the sensors 215 may include linear position sensors, rotary position sensors, pressure sensors, flow rate sensors, inertial measurement units (IMU) devices, accelerometers, temperature sensors, and/or other sensors. [0048] In one example, the input 205 may travel to the controller 210 for analysis by the controller 210. In one example, the controller 210 may be fluidically and/or electrically connected to the pumps 102 and the flow control devices 142 of the hydraulic circuit 100 to control a status of the hydraulic circuit 100. For example, based on the inputs 205 and information from the sensors 215, the controller 210 may open, close, and/or partially open and/or close one or more of the flow control devices 142 and/or turn on/tum off one or more of the pumps 102. Thus, the controller 210 may control the flow rate and/or pressure received by the consumers 122 from the pumps 102 based on the input 205 and information from the sensors 215. In one particular example, the controller 210 is configured to control the flow of hydraulic fluid from the pumps 102 to the consumers 122 via operation of the one or more flow control devices 142 to optimize efficiency of the hydraulic circuit 100. Thus, the controller 210 may prioritize particular consumers 122 and pumps 102 combinations based on a variety of factors.

[0049] An example logic flow diagram 300 for the controller 210 is illustrated in FIGS. 3A and 3B. In one example, the logic flow diagram 300 is configured to optimize efficiency of the hydraulic circuit 100, such that overall efficiency losses within the hydraulic circuit 100 are reduced. At stage 305 the controller 210 can determine a demanded and/or required pressure for each of the consumers 122 via the one or more sensors 215. In another example, the controller 210 can determine the demanded pressure from each of the consumers 122 based on the inputs 205. In one example, at stage 310 the controller 210 can then begin to arrange the consumers 122 into “groups” with consumers having similar pressure demands. For example, consumers 122 with pressure demands within a predetermined range may be grouped together. In one particular example, the consumers within a pressure range of +/- 50 bar may be grouped together (e.g., with a first group being from 75 bar to 125 bar, a second group being from 125 bar to 175 bar, etc ). However, grouping can be based on other pressure ranges as well. In some cases, a single or multiple consumers may be within a predefined pressure range corresponding with a group. Accordingly, it is to be understood that a “group” of consumers (or pumps) is defined as including one or more consumers (or pumps). Accordingly, a group of consumers can, for example, include, one, two, three, etc. consumers.

[0050] At stage 315 the controller may determine a flow demand for each group. For example, the controller 210 may determine a total flow demand per group based on the inputs 205, sensors 215, and/or other methods. In one example, the controller 210 may begin by determining the flow demand of each individual consumer within a group. Following this, the controller 210 may add the individual consumer flow demands together (e g , based on grouped consumers) to calculate a total flow demand for each group. At stage 320, the controller 210 determines a pressure required for each group. In one example, the pressure required is the highest pressure demanded by a consumer in each group. For example, a group having consumers with pressure demands from 110-100 bar would have a pressure setpoint of 110 bar. [0051] At stage 325, the controller 210 assigns pumps to the groups based on the demanded (total) flow rate of each group and the available flow rate of the pumps. Put differently, the controller 210 further groups each consumer group with one or more pumps (i.e., a corresponding group of pumps), such that each group of pumps outputs pressure at the pressure setpoint of its corresponding group of consumers to mitigate efficiency losses due to compensation. In other words, the controller 210 determines what pressure each pump group, and thus each individual pump, will output based on the pressure of the group supplied by the pump and/or pumps.

[0052] At stage 330, the controller 210 begins to allocate flow from the pumps to consumers within each group. As can be seen in FIG. 3B, at stage 340, the controller 210 determines if each consumer within the groups will receive the demanded flow rate from the grouped pump and/or pumps. Put differently, the controller 210 compares the available flow rate from each pump group to the flow rate demanded by its corresponding group of consumers to determine whether each consumer will receive its demanded flow rate. If each consumer will receive its demanded flow rate the controller 210 begins to supply and/or enable flow from the pumps to the grouped and/or matched consumers at stage 335.

[0053] At stage 345, if the controller 210 determines that one or more consumers will not receive its demanded flow rate the controller 210 determines whether there is any remaining available flow from one or more pumps matched to another group. For example, the controller 210 determines whether there is additional available flow from a pump assigned to a group at a different pressure. If no additional flow rate is available and/or the additional available flow rate is at a pressure outside of a predetermined efficiency threshold the controller 210 does not assign additional flow rate to the unsatisfied consumers. Thus, the controller 210 begins to supply and/or enable flow from the pumps to the grouped and/or matched consumers based on a predetermined prioritization schedule. If there is additional flow available from one or more pumps at an unmatched pressure the controller 210 moves to stage 350.

[0054] At stage 350, the controller 210 allocates additional flow from the one or more unmatched pressure pumps to the unsatisfied consumers. In one example, the additional flow from the one or more unmatched pressure pumps is at a higher pressure than that demanded by the unsatisfied consumers. Thus, the one or more flow' control devices may compensate the pressure to the value required by the unsatisfied consumers. As mentioned previously, the controller 210 may enable compensation of pressure between high and medium pressure and/or medium and low pressure as the efficiency losses are within the predetermined efficiency band. However, in other examples, the controller 210 may disable compensation of pressure between high and low pressure as the efficiency losses are outside of the predetermined efficiency band. In one example, the pressure threshold between high, medium, and low pressures may be a difference of approximately 50 bar each. Thus, high pressure may be in a range of 150-100 bar, medium pressure may be in a range of 100-50 bar, and low pressure may be in a range of 50-0 bar. However, alternative pressure ranges are envisioned.

[0055] Various non-limiting example applications of the logic flow diagram 300 used by the controller 210 are illustrated with respect to FIGS. 4-17. However, other example applications of the logic flow diagram 300 are envisioned. For reference in FIGS. 4-17, Qavaii is a maximum available flow rate of a pump, Qdem is a flow rate demanded by a consumer, Qrcvd is a total flow rate received by a consumer, Pset is a relative pressure value produced by a pump (e.g., low, medium, or high pressure), Pdem is relative pressure value demanded by a consumer, and Group is the pump group selected by a controller to supply a consumer.

[0056] FIG. 4 shows an example pump allocation 400 including a pair of pumps and a pair of consumers. Consumer 1 (e.g., first consumer 125) and consumer 2 (e.g., second consumer 130) each demand high pressure at a flow rate of 200 liters/minute (1pm). The controller 210 assigns pump 1 (e.g., first pump 105) and pump 2 (e.g., second pump 110) as high pressure pumps. Thus, the controller 210 groups pump 1 with consumer 1 and groups pump 2 with consumer 2. Thus, in this configuration, a single pump serves a single consumer, which optimizes efficiency of the system. Further, each pumps demanded flow is met.

[0057] FIG. 5 shows an example pump allocation 500 including a single consumer (e.g., first consumer 125) demanding high pressure at a flow rate of 200 1pm. The controller 210 determines that pump 1 (e.g., first pump 105) and pump 2 (e.g., second pump 110) are each capable of outputting high pressure flow at a flow rate of 100 1pm. Thus, the controller 210 groups both pumps 1 and 2 with consumer 1. In this configuration, both pumps 1 and 2 supply a single consumer (consumer 1) to meet the flow rate demanded by the consumer, at the demanded pressure.

[0058] FIG. 6 shows an example pump allocation 600 including four (4) consumers and four (4) pumps. For example, consumers 1 and 2 each demand high pressure at a flow rate of 200 1pm and consumers 3 and 4 each demand low pressure at a flow rate of 100 1pm. The controller 210 then determines that pumps 1 and 2 are each able to provide high pressure at a rate of 200 1pm and pumps 3 and 4 are each able to provide low pressure at a flow rate of 100 1pm. Thus, the controller 210 groups consumer 1 and pump 1, consumer 2 and pump 2, consumer 3 and pump 3, and consumer 4 and pump 4. In this configuration, each pump supplies a single consumer at its demanded pressure and flow rate, which optimizes efficiency of the system.

[0059] FIG. 7 shows an example pump allocation 700 including a pair of consumers (e.g., consumer 1 and consumer 2) and four (4) pumps. Consumer 1 demands high pressure at a flow rate of 2001pm and consumer 2 demands low pressure at a flow rate of 100 1pm. The controller 210 determines that pump 1 is able to provide high pressure at a flow rate of 200 1pm and pump 3 is able to provide low pressure at a flow rate of 1001pm. Thus, the controller groups consumer 1 and pump 1 and groups consumer 2 and pump 3, so that each consumer is provided with the demanded flow rate and pressure. In this configuration, pumps 2 and 4 remain idle as additional flow rate is not required.

[0060] FIG. 8 shows an example pump allocation 800 including four (4) consumers and two (2) pumps. Consumers 1 and 2 each demand high pressure at a flow rate of 100 1pm and consumers 3 and 4 each demand low pressure at a flow rate of 100 1pm. The controller 210 determines that pump 1 is able to supply a flow rate of 200 1pm at high pressure and that pump 3 is able to provide a flow rate of 100 1pm at low pressure. Thus, the controller groups consumers 1 and 2 with pump 1 and groups consumers 3 and 4 with pump 3. In this configuration, pump 1 splits the 200 1pm flow rate to fulfil both consumers 1 and 2. However, pump 3 only being capable of supplying a flow rate of 100 1pm cannot fulfil both consumer 3 and 4, each of which demands a flow rate of 100 1pm for a total flow rate of 200 1pm. Thus, the controller 210 splits the flow' rate from pump 3 between consumers 3 and 4 (e.g., 50 1pm flow rate to each).

[0061] FIG. 9 shows an example pump allocation 900 including four (4) consumers and two (2) pumps. Consumers 1 and 2 each demand high pressure at a flow rate of 200 1pm and consumers 3 and 4 each demand low pressure at a flow rate of 100 1pm. The controller 210 determines that pump 1 is able to supply a flow rate of 200 1pm at high pressure and that pump 3 is able to provide a flow rate of 100 1pm at low pressure. Thus, the controller groups consumers 1 and 2 with pump 1 and groups consumers 3 and 4 with pump 3. In this configuration, as pump 1 has a flow rate of 200 1pm and cannot fulfil both consumer 1 and 2, which together require a flow rate of 400 1pm, the controller 210 splits the flow rate from pump 1 between consumers 1 and 2 (e.g., 100 1pm flow rate to each). Similarly, as pump 3 has a flow rate of 100 1pm and cannot fulfil both consumer 3 and 4, which together require a flow rate of 200 1pm, the controller 210 splits the flow rate from pump 3 between consumers 3 and 4 (e.g., 50 1pm flow rate to each). [0062] FIG. 10 shows an example pump allocation 1000 including six (6) consumers and four (4) pumps. Consumers 1 and 2 each demand high pressure at a flow rate of 50 1pm, consumers 3 and 4 each demand medium pressure at a flow rate of 100 1pm, consumer 5 demands low pressure at a flow rate of 200 1pm, and consumer 6 demands low pressure at a flow rate of 100 1pm. The controller 210 determines that pump 1 is able to supply a flow rate of 2001pm at high pressure, pump 2 is able to supply a flow rate of 2001pm at medium pressure, and both pumps 3 and 4 are able to provide a flow rate of 100 1pm at low pressure. Thus, the controller 210 groups consumers 1 and 2 with pump 1, groups consumers 3 and 4 with pump 2, groups consumer 5 with pump 3, and groups consumer 6 with pump 4. Thus, pump 1 splits flow between consumers 1 and 2, pump 2 splits flow between consumers 3 and 4, and consumers 5 and 6 each have dedicated pumps. However, consumer 5 is only able to receive half the demanded flow rate from pump 3 (e.g., receives flow rate of 100 1pm when 200 1pm demanded). While it is possible to fulfill the remaining flow demand for consumer 5 with pump 1, the controller 210 does not supply the available 100 1pm flow rate from pump 1 to fulfil consumer 5 as pump 1 is high pressure and consumer 5 demands low pressure, thus the compensation of pressure via the flow control device would be beyond the efficiency standards allowed by the controller 210. In some cases, other factors may determine whether supplying additional flow is feasible, such a maximum power output of a motor or engine supplying power to the pumps. However, in other examples, the controller 210 may allow pump 1 to provide the additional 100 1pm to consumer 5, for example, in scenarios where maximum hydraulic power is desired rather than maximum efficiency. In such cases, the pressure of pump 1 would remain high in order to also provide flow to consumers 1 and 2, and the pressure would be compensated by a flow control device so that consumer 5 receives low pressure.

[0063] FIG. 11 shows an example pump allocation 1100 including six (6) consumers and four (4) pumps. Consumers 1 and 2 each demand high pressure at a flow rate of 50 1pm, consumers 3 and 4 each demand medium pressure at a flow rate of 100 1pm, consumer 5 demands low pressure at a flow rate of 200 1pm, and consumer 6 demands low pressure at a flow rate of 100 1pm. The controller 210 determines that pump 1 is able to supply a flow rate of 200 1pm at high pressure, pump 2 is able to supply a flow rate of 200 1pm at low pressure, pump 3 is able to supply a flow rate of 100 1pm at medium pressure, and pump 4 is able to provide a flow rate of 100 1pm at low pressure. Thus, the controller 210 groups consumers 1 and 2 with pump 1, groups consumers 3 and 4 with pump 3, groups consumer 5 with pump 2, and groups consumer 6 with pump 4. Thus, pump 1 splits flow between consumers 1 and 2. Pump 2 supplies flow to consumer 5. Pump 3 splits flow between consumer 3 and 4, but does not fulfil the flow rate demands of consumers 3 and 4. And, pump 4 supplies consumer 5. Note, the controller 210 could enable the additional 100 1pm flow rate at high pressure from pump 1 to fulfil the additional 100 flow rate at medium pressure demanded by consumers 3 and 4 to fully supply consumers 3 and 4 in scenarios where maximum hy draulic power is desired rather than maximum efficiency.

[0064] FIG. 12 shows an example pump allocation 1200 including six (6) consumers and four (4) pumps. Consumers 1 and 2 each demand high pressure at a flow rate of 50 1pm, consumers 3 and 4 each demand medium pressure at a flow rate of 100 1pm, consumer 5 demands low pressure at a flow rate of 300 1pm, and consumer 6 demands low pressure at a flow rate of 100 1pm. The controller 210 determines that pump 1 is able to supply a flow rate of 2001pm at high pressure, pump 2 is able to supply a flow rate of 2001pm at medium pressure, and both pumps 3 and 4 are able to provide a flow rate of 100 1pm at low pressure. Thus, the controller 210 groups consumers 1 and 2 with pump 1, groups consumers 3 and 4 with pump 2, groups consumer 5 with pumps 3 and 4, and groups consumer 6 with pump 4. Thus, pump 1 splits flow between consumers 1 and 2, pump 2 splits flow between consumers 3 and 4, pump 3 supplies flow to consumer 5, and pump 4 supplies flow to consumers 5 and 6. Thus, both of consumers 5 and 6 are fulfilled at half their demanded flow rates. Put differently, the controller 210 may determine to fill each of the consumers flow rate demands at half the demanded flow rate to enable operation of the consumer. In other examples, it may be possible to distribute flow from pumps 3 and 4 to consumers 5 and 6 in other ways to achieve a desired performance of each. For example, pumps 3 and 4 can supply 200 1pm to consumer 5 and none (0 1pm) to consumer 6, or supply 100 1pm to consumer 6 with the remainder to consumer 5, etc.

[0065] FIG. 13 shows an example of a portion of a dig action 1300 for use with a material handling vehicle. For example, the dig action 1300 may be used with an off-highway material handling vehicle (e.g., an excavator and/or other off-highway material handling vehicle). In one example, during a digging action by the vehicle, operation of a bucket may demand 501pm flow rate at a medium pressure, which can be fully supplied via pump 2. Additionally, operation of the arm may demand 100 1pm flow rate at a high pressure, which could be fully supplied by pump 1. How ever, doing so would leave no flow available to operate the boom, which demands 30 1pm flow rate at medium pressure. Thus, to fulfil both the arm and the boom partially, the controller 210 allocates 70 1pm flow rate at the high pressure to the arm and compensates flow from the pump to the boom to supply the full 301pm flow rate to the boom at medium pressure. [0066] FIG. 14 shows an example of another portion of a dig action 1400 of the vehicle. In the dig action 1400, the arm demands 100 1pm flow rate at high pressure, which is fulfilled by pump 1. Additionally, the boom and the bucket each demand 30 1pm flow rate at medium pressure, which is supplied by pump 2. Thus, the controller 210 groups the boom and bucket with pump 2 and groups the arm with pump 1, such that no compensation is needed.

[0067] FIG. 15 shows an example of a dump action 1500 of the vehicle. In the dump action 1500, the boom demands 1001pm flow rate at high pressure, which is supplied by pump 1. The arm and bucket each demand 30 1pm flow rate at a medium pressure, which is supplied by pump 2. Additionally, the swing function requires 100 1pm flow rate at a high pressure, which is supplied by pump 3. Thus, the controller 210 groups the boom with pump 1, groups the arm and bucket with pump 2, and groups the swing with pump 3.

[0068] FIG. 16 shows an example of an end of dump action 1600 of the vehicle. In the end of dump action 1600, the bucket demands 100 1pm flow rate at low pressure, which is supplied by pump 2. Additionally, the arm demands 30 1pm flow rate at medium pressure, which is supplied by pump 1. Thus, the controller 210 groups the arm with pump 1 and the bucket with pump 2.

[0069] FIG. 17 shows an example of a return action 1700 of the excavator. In the return action 1700, the swing demands 1001pm flow rate at high pressure, which is supplied by pump 3. The boom demands 30 1pm flow rate at a low pressure, which is supplied by pump 1. Additionally, the arm and bucket each demand 30 1pm flow rate at medium pressure, which is supplied by pump 2. Thus, the controller 210 groups the boom with pump 1 , the arm and bucket both with pump 2, and the swing with pump 3.

[0070] Various non-limiting pump combinations are envisioned for the hydraulic circuit 100. For example, the hydraulic circuit 100 may include a fixed pump in combination with another fixed pump, a fixed pump in combination with an electrohydraulically controlled (EH) positive pump, a fixed pump in combination with a pressure compensating/load sensing (PCLS) pump, a fixed pump in combination with an accumulator, an EH positive pump in combination with another EH positive pump, an EH positive pump in combination with a PCLS pump, an EH positive pump in combination with an accumulator, a PCLS pump in combination with another PCLS pump, a PCLS pump in combination with an accumulator, and an accumulator in combination with another accumulator.

[0071] Within this specification embodiments have been described in a way which enables a clear and concise specification to be written, but it is intended and will be appreciated that embodiments may be variously combined or separated without parting from the invention. For example, it will be appreciated that all preferred features described herein are applicable to all aspects of the invention described herein. [0072] Thus, while the invention has been described in connection with particular embodiments and examples, the invention is not necessarily so limited, and that numerous other embodiments, examples, uses, modifications and departures from the embodiments, examples and uses are intended to be encompassed by the claims attached hereto. The entire disclosure of each patent and publication cited herein is incorporated by reference, as if each such patent or publication were individually incorporated by reference herein.

[0073] Various features and advantages of the invention are set forth in the following claims.