Technical fields subject to the invention

The invention is related to the field of guidance and control of autonomous vehicle movement. It covers the technical areas for safe self-driving of vehicles from the starting point to the destination. The technology of the invention is based on radio wave communication, Internet services and cloud technologies, on data protection techniques and management of vehicle and fleet systems. Specifically, the invention relates to vehicle movement control using RFID technology within a predefined and limited zone.

Technical issue he problem that needs to be resolved is how to quickly and safely introduce autonomy into the traffic ecosystem without using expensive and complex technologies. Traffic jams are an increasing problem for cities, while activities, aimed at resolving this issue are significant not only for reducing traffic congestion, but also with respect to the ecological aspect, in terms of reducing pollution. The proposed technology would ensure a rapid achievement of vehicle autonomy, to be used as dedicated means of transport for transporting goods and passengers. The ultimate goal of the invention is to reduce city traffic jams by introducing fleets of autonomous vehicles, rented for the transport of goods and passengers, and that achieve autonomy by applying RFID technology with ensured data protection, that the vehicle takes from RFID tags using encryption techniques.

Such vehicles would be used at the request of the user, as needed. From the technical aspect, the problem of applying expensive technologies such as radar, lidar, cameras and various other sensors, and artificial intelligence technology, which is still largely unreliable for application in order to achieve autonomous vehicle movement, is resolved. In addition, performance issues, related to UHF RFID technology, are addressed, including what types of RFID tags can be used for autonomous vehicle navigation purposes and how to install RFID readers in asphalt to obtain the most optimal reading area when the tags are used as sensors, so as to improve the accuracy of the navigation system - GPS. State of the technology

The existing technology includes inventions that can be said to have the same goal of solving existing problems, however, among the given inventions none deal with data protection nor do they provide a system that prevents the system vehicle from receiving information from an RF tag from another system, which leads to errors in functioning. The given inventions do not offer data protection solutions using data encryption techniques, or any other protection method that ensures that the vehicle does not retrieve data from the RF tag of another system.

Patent application number US11151339B2 published on November 12, 2014, entitled "Method and system for charging electric autonomous vehicles" provides a method and system for guiding an autonomous electric vehicle to the first battery charging station and a method for charging electric vehicle batteries. The method is based on a software solution that lists the vehicle, with the help of RFID tags embedded in the asphalt. Tag detection is performed using a tag reader located on an autonomous electric vehicle. RFID tags embedded in asphalt are connected to readers on autonomous electric vehicles to avoid the possibility of reading a tag that does not belong to the system. The method of connecting and reading tags is not defined in the application, in the sense that it is not given how RFID tags and readers are "recognized" and whether there is additional data protection against theft of data owned by the tag.

Patent application US20200258392A1 published on September 14, 2017 entitled "Navigation techniques for autonomous and semi-autonomous vehicles" foresees techniques for managing a self-driving vehicle, or a driver-assistance vehicle, or another autonomous or semi-autonomous machine. The method includes transmitting a signal, via ultra-high frequency (UFH) to one or more markers, receiving return signals, at a radar transceiver via another frequency range different from the UFH range, and determining one or more estimated locations of the navigation system based on return signals.

The system is based on RFID tags that can work on millimeter radio waves, they can be passive and battery-powered, or active that generate certain data for the needs of system operation and forward this data to the control center via the broadcast. Each system tag has its own identification. Tag identification information may include a tag identifier that provides a unique identifier for the marker and/or geographic coordinates associated with the marker within which the marker is located. The system is designed to transmit a signal, via the ultra-high frequency range, to one or more markers. On the other hand, the return signals, from one or more markers, are received on the radar transceiver via another frequency range different from the UHF range. In this manner, one or more estimated locations of the navigation system are determined based on the return signals. Patent application US20200025575A1 published on July 19, 2018 entitled "Navigation techniques for autonomous and semi-autonomous vehicles" gives techniques that provide highly accurate localization of autonomous and semi-autonomous vehicles that can be used for vehicle navigation through infrastructure. Localization techniques can use vehicle lidar and/or radar to detect radar and/or reflective markers placed along and/or around the roadway. At least some of the radar-reflective markers may include a millimeter wave radio-identification tag (RFID- MMID) placed on the marker that can be activated by a radar signal emitted by the navigation system of the autonomous or semi-autonomous vehicle. RFID-MMID tags can be configured to transmit a modulated signal that includes tag identifier information and/or geographic coordinates of the marker on which the RFID-MMID tag is placed. The smallest part of these markers can be radar-reflective markers and can include an RFID tag. The RFID can be mounted on a millimeter wave antenna and can be placed against a pole as a marker near the road.

Patent application US10393852B2 published on September 16, 2015 entitled "Method and system of location estimation and navigation of autonomous vehicles" provides a solution for estimating the location of an autonomous vehicle. A method has been foreseen which includes scanning at least one radio frequency identification (RFID) tag, to obtain an identifier of the RFID tag; querying the database using the identifier of at least one RFID tag to collect information about the location of at least one RFID tag; determining the bias of the vehicle in relation to the location of a scanned, no less than, one RFID tag; and calculating the location of the vehicle based on the bias and the location of at least one RFID tag.

Patent application US11010998B 1 published on October 5, 2010 entitled "Systems and methods for vehicles with limited destination ability" generally refers to limiting the use of an autonomous or semi-autonomous vehicle based on limiting data. Limitation data gives permission to the vehicle and may include destinations, routes and/or other user-defined information. The vehicle accesses the permit data in order to transport a specific passenger to a predefined destination, for example, without deviating from a predefined route. The vehicle can leave a certain passenger at a destination and can wait for the user if he has defined several destinations in one request.

Works addressing similar issues, as the subject invention, are:

The paper "Automated Guided Vehicle (AGV) Navigation Control using Matrix Method Applying Radio Frequency Identification (RFID) Point Address" published in 2021 and refers to an automated guided vehicle (AVG), a tool often used in the industrial world as an automatic vehicle for the transport of materials from the point of collection to the point of delivery, and can be controlled remotely, is a solution for simplifying work in the industrial world. In this study, the AVG robot can be controlled using wireless communication and can perform requests remotely. To map the robot's path, this solution uses a Radio Frequency Identification (RFID) point tag for robot navigation purposes. Based on the test results, the robot can work and correctly detect the address of the RFID tags.

The paper "Automatic Guided Vehicle (AGV) Design Using an loT-based RFID for Location Determination" published in 2020 provides a solution where AVG and loT are the focus of this research in which AVG is integrated with a line follower and RFID for localization in an industrial environment. AVG, which moves along the line, has the ability to read predetermined locations using RFID tags. Location data will be sent from the AVG to the server computer using loT, which facilitates data transfer. The data sent by the robot will be received by the server computer and displayed on the monitor. As the movement of the robot is fully controlled by the server computer, the results of this research are expected to have a significant impact on the application of AVG and loT in the Industry 4.0 era.

Presenting the essence of the invention

The idea that fueled the development of autonomous vehicles aims to safely and efficiently manage a vehicle without the need for the vehicle to be directly controlled by a human. Such vehicles consist of the integration of several systems that work together to connect the vehicle with the environment, and the most important system for this purpose is the sensor system built into the vehicle. The vehicle navigation system is one of the most important systems for detecting the current position of the vehicle and the state of the traffic infrastructure and the outside world. Navigation is needed so that autonomous vehicles can work independently using sensors and specific algorithms whose role is to recognize the world in the vehicle's immediate environment. The application of several different types of sensors, whose outputs are combined by sensor fusion methods to produce a result that is fed into the navigation system, is an absolute necessity. Using GPS on its own has disadvantages related to accuracy, so that vehicle navigation routes, obtained based on coordinates from a GPS navigation system, often need to be corrected. This correction can be applied by adding a compass module to the navigation system, or by adding other sensors such as lane marking sensors, Inertial Measurement Unit/Inertial Navigation System - IMU/INS, while one of the more interesting technologies for this purpose is Radio Frequency Identification (RFID) technology.

Radio frequency identification, as a wireless information transmission technology, has a broad range of applications for the purpose of identifying individual objects by means of radio waves. Such a system is impossible to establish without the existence of hardware and software components, however, the unsurpassed advantage of RFID technology is the simplicity of the hardware, which consists of a tag and a reader used to send and receive radio waves. An additional feature of this system is that it provides the ability to read a larger number of tags per second.

Autonomous vehicle system and vehicle navigation can be implemented by combining data reading using RFID readers from installed RFID tags on the road and reading GPS data in the form of coordinates that provide information about the vehicle's position, with the application of the GPS - RFID localization method, The navigation algorithm processes this data into information about the route and location of the vehicle, thus ensuring complete accuracy of the system’s operation with precise location information.

The subject invention deals precisely with this issue and combining the operation of the GPS navigation system with RFID localization. The proposed solution overcomes the problem related to the performance of UHF RFID technology, the application of RFID tags that can be used for the needs of autonomous vehicle navigation, and the problem of how to install the RFID reader so as to ensure an optimal tag reading area, when the tags are used as a sensor for the purpose of improving GPS accuracy. The proposed system uses passive RFID tags whose range is relatively long. The range performance of the tags is greatly affected by the operating temperature, and performance can be improved by adjusting the angle and frequency of the tags. One of the most important features of RFID technology is that the reading range of the RFID reader is quite wide, i.e.. up to 40°, and this response is good even at a speed of 60 km/h, which is ideal for use in populated areas. Vehicle-mounted GPS receivers used for positioning are often limited in accuracy. A simple solution to the problem is GPS/RFID integration that improves system performance and accuracy that navigation systems alone are unable to achieve.

Passive tags can be highlighted by the fact that they do not have their own energy source, so accordingly, there is no initiation of contact with readers, which is achieved by active tags. This feature gives an additional advantage to the proposed system because there is no need to control the battery capacity and replace the tag batteries when necessary. However, for the functionality of this type of tags, energy is obtained through the signals sent to them by the reader. The signal from the reader carries a request to send information about the position of the vehicle to which the tag responds. This application of passive tags points to the high degree of commercialization in all areas, not only for the needs of vehicle navigation.

Brief description of the invention drawings

Figure 1 Procedure for forming a request 360 for transportation by an autonomous vehicle 330

Figure 2 The procedure for executing autonomous driving according to request 360

Figure 3 Autonomous transport system

Figure 4 Position of tags 400 on asphalt 420

Figure 5 Block diagram of RFID reader 410

Figure 6 Block diagram of RFID tag 400

Detailed description of the invention

RFID technology is an automatic identification technology that enables the tracking of people and objects. The information obtained is identity and location data, the procedure used to obtain these two types of data is the localization of RFID tags 400 that are attached to a device or object. RFID is characterized by low energy consumption and virtually unlimited identification capacity. In addition to this, the RFID tags 400 have other advantages such as the labeling of objects with the RFID tags 400, the environment can be identified in a cost-effective and energyefficient manner, and this technology has been shown to be able to overcome problems of cost and very good accuracy.

The proposed system (Figure 3) provides a solution in which the user 310 sends a request 360 for transportation through an application on a mobile phone 320. This request 360 together with the coordinates of the user's current position arriving from the GPS navigation application located on the user's mobile phone 320 is received by the Cloud server 300 in step 100 . The processing of request 360 Cloud server 300 is performed in step 110 in which, based on the GPS coordinates and the received data from the application from mobile phone 320 of user 310, a path 340 is determined that provides navigation to the specific vehicle 330 from its current destination C to the destination A of user 310 and in step 120, a path 350 that provides navigation to the vehicle 330 from the destination A of user 310 to the desired destination B. Both defined paths 340 and 350 are forwarded by step 130 to the specific vehicle 330 for execution.

Vehicle 330 is started by step 200, receiving paths 340 and 350 from the Cloud server 300, in order to fulfill request 360 from user 310. According to request 360 from user 310, vehicle 330 first drives according to path 340 via step 210. During the navigation of vehicle 330 on path 340, RFID reader 410 placed on the floor of vehicle 330 will emit radio waves in the form of signal 430, carrying a message formed by microcontroller 530 from RFID reader 410. This message contains a request to RFID tag 400 asking RFID tag 400 to transmit the coordinates of its position. Signal 430, with the request message, is formed in RF signal generator 520, and in encryption block 510 an encrypted key is added to the message in order to further protect the autonomous navigation system from misuse of data from tags 400, and with the aim that the reader does not process the data of someone from another navigation system, that is, to receive messages only from the system to which it belongs. Signal 430 is transmitted by antenna 500 from reader 410 on vehicle 330.

RFID tag 400 of the subject navigation system belongs to the passive group that does not have its own power supply, but with the reception of signal 430, tag 400, from the radio waves in the capacitor of the rectifying circuit 630, generates the energy required for its work. A system constructed in this manner has the additional advantage that tags 400 do not need to have their battery replaced when necessary, there is no possibility that, some of, tags 400 will remain without power until the battery is replaced, and in addition to a more energy-efficient solution, the tag 400 itself is smaller in size.

When RFID tag 400 receives signal 430, which is first decrypted in block 610, processor 640 from tag 400 is activated and, based on the request, prepares a response - feedback, by pulling data stored in memory 650 of tag 400. An encryption key is added to the formed response in block 610 and the thus prepared signal 440 is transmitted by transponder 620 via antenna 600 back to reader 410 on vehicle 330.

Antenna 560 will receive signal 440, decryption block 550 will check whether the message belongs to the system. Before microcontroller 530 from reader 410 sends the received data to the on-board computer 330, signal decoding will be performed in block 540.

The vehicle computer 330 will read the data from tag 400 in step 220, then in step 230 it will check whether the predefined path 340 is correct, by comparing the coordinates received from tag 400 and the data received from Cloud server 300. If an error has occurred, step 270 will correct it and then proceed to step 240. If path 340, according to the coordinates received from tag 400, is correct, this loop will be skipped. Verification of the vehicle’s arrival at the destination is carried out in step 240. If not, the whole procedure is repeated. RFID reader 410 of vehicle 330 will continue to send signals 430 and receive signals 440 from tag 400, which the vehicle's computer will process by going through steps 230 and 240 until step 250 is reached at the exit of step 240, indicating that vehicle 330 has arrived at destination A, picked up user 310 and is now driving along predefined path 350 in step 250.

The procedure for driving on route 350 is the same as the procedure described for route 340, with the exception that when vehicle 330 arrives at desired destination B by exiting step 260, the procedure ends and the vehicle waits for a new request 360 for driving from the same or another user 310. The described system and procedure can be used for transporting both passengers and goods. The system is limited to the existing infrastructure of tags 400, and the execution of autonomous driving is possible only along the paths where system tags 400 are installed. This limitation does not diminish the advantages of the practical application of the solution and its scalability. Which means the system can be easily expanded by adding new tags 400. It should also be emphasized that reader 410 will not read data from each tag 400 while driving, but this does not mean that vehicle 330 will go astray. What is important is that each vehicle 330, in a system, has in its memory recorded positions for each tag 400, from the system in its memory, and in case tag 400 does not receive signal 430, to which it is required to send signal 440 as feedback, vehicle 330 will know its exact position for retrieving information on the position of tags 400 on path 340 or path 350, from its memory.

The infrastructure of the proposed navigation system is made by embedding passive RFID tags 400 in asphalt 420, at a mutual distance of 10 meters on both sides of the road, as presented in Figure 4.

Method of industrial or other application of the invention

The given solution achieves a simple, cheap, and easily controlled system that finds application in industrial and factory infrastructure as well as in free traffic for the transportation of passengers, goods such as taxi organizations, courier services, etc.