# US 11,079,237 B2 · Method for determining a relative position of a motor vehicle, position determination system for a motor vehicle and motor vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,079,237 B2 - Document ID: US11079237B2 - Status: Granted - Kind: B2 - Application number: 16/463,149 - Filed: 2017-11-09 - Published: 2019-09-26 - Granted: 2021-08-03 - Earliest claimed: 2016-12-15 - Assignees: Audi AG - Applicants: Audi AG - Inventors: Christopher Demiral - Web page: https://patentgrep.com/patent/US11079237B2 ## CPC - G01C 22/02: by conversion into electric waveforms and subsequent integration, e.g. using tachometer generator {(G01C22/002, G01C22/004, G01C22/006 take precedence)} - B62D 15/02: Steering position indicators {; Steering position determination; Steering aids} - B62D 15/021: {Determination of steering angle} - G07C 5/085: {using electronic data carriers} - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) - B62D: MOTOR VEHICLES; TRAILERS (steering, or guiding on a desired track, of agricultural machines or implements A01B69/00; wheels, castors, axles, increasing wheel adhesion B60B; vehicle tyres, tyre inflation or tyre changing B60C; connections between vehicles of a train or the like B60D; vehicles for use on rail and road, amphibious or convertible vehicles B60F; suspension arrangements B60G; heating, cooling, ventilating or other air treating devices B60H; windows, windscreens, non-fixed roofs, doors or similar devices, protective coverings for vehicles not in use B60J; propulsion plant arrangements, auxiliary drives, transmissions, controls, instrumentation or dashboards B60K; electric equipment or propulsion of electrically-propelled vehicles B60L; power supply for electrically-propelled vehicles B60M; passenger accommodation not otherwise provided for B60N; adaptations for load transportation or to carry special loads or objects B60P; arrangement of signalling or lighting devices, the mounting or supporting thereof or circuits therefor, for vehicles in general B60Q; vehicles, vehicle fittings or vehicle parts not otherwise provided for B60R; servicing, cleaning, repairing, supporting, lifting, or manoeuvring, not otherwise provided for, B60S; brake arrangements, brake control systems or parts thereof B60T; air-cushion vehicles B60V; motor-cycles, accessories therefor B62J, B62K; testing of vehicles G01M) - G07C: TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE ## Abstract The invention present application relates to a method for determining a current position (xk+1, yk+1) of a motor vehicle relative to an initial position (xk, yk) previously held by the motor vehicle. Changes in the wheel position between the initial position (xk, yk) and the current position (xk+1, yk+1) are measured for at least two wheels of the motor vehicle. A motion vector of the motor vehicle is individually calculated from each of the wheel position changes. The individual motion vectors are then averaged. The current position (xk+1, yk+1) is then determined by adding the averaged motion vector, which, starting from a reference direction, has been rotated by a yaw angle of the motor vehicle, wherein the yaw angle is determined using a yaw rate provided by a yaw rate sensor of the motor vehicle. The invention also relates to a position determination system and to a motor vehicle equipped with such a system. ## Claims ### Claim 1 A method, comprising: measuring, at a sensor device, a change in a wheel position of a motor vehicle for at least two wheels of the motor vehicle from an initial position at coordinates (xk, yk) to a current position (xk+1, yk+1); determining, at a calculation device, a motion vector corresponding to the change in the wheel position for each wheel of the at least two wheels of the motor vehicle; generating, at the calculation device, an averaged motion vector based on the motion vector corresponding to the change in the wheel position for the each wheel; determining a yaw angle of the motor vehicle in response to a yaw rate provided by a yaw rate sensor; in response to the determined yaw angle of the motor vehicle, rotating, at the calculation device, the averaged motion vector by the determined yaw angle from the initial position, thereby determining the current position of the motor vehicle. ### Claim 2 (depends on 1) The method of claim 1, further comprising determining an average yaw angle of the motor vehicle, wherein the averaged motion vector is rotated by the average yaw angle from the initial position. ### Claim 3 (depends on 1) The method of claim 1, further comprising calculating the current position Pk+1 of the motor vehicle at (xk+1, yk+1) coordinates as Pk+1=Pk+S·R(δ), wherein Pk is the initial position of the motor vehicle at coordinates (xk, yk), wherein s is the averaged motion vector, wherein R(δ) is a rotation matrix which rotates the averaged motion vector by the yaw angle δ calculated as (yawk+0.5·Δtyawrate), wherein yawrate being the yaw rate provided by the yaw rate sensor, yawk being an initial alignment at the initial position, and Δt being a time elapsed during the motor vehicle movement from the initial position to the current position. ### Claim 4 (depends on 1) The method of claim 1, further comprising determining the motion vector based on a wheel steering angle or an Ackermann geometry of the motor vehicle. ### Claim 5 (depends on 1) The method of claim 1, further comprising converting the change in the wheel position for each wheel into a corresponding motion vector of a vehicle-specific reference point, wherein the vehicle-specific reference point is used for calculating the change in the wheel position. ### Claim 6 (depends on 1) The method of claim 1, wherein the yaw rate is provided by the yaw rate sensor at every 10 milliseconds (ms) or 20 ms. ### Claim 7 (depends on 1) The method of claim 1, wherein the change in the wheel position is measured for the wheels spaced apart from one another along a longitudinal extension of the motor vehicle. ### Claim 8 (depends on 1) The method of claim 1, wherein the motion vector corresponding to the change in the wheel position of each wheel of the motor vehicle is determined in parallel. ### Claim 9 (depends on 1) The method of claim 1, wherein the calculation device is a control unit comprising a processor and a memory. ### Claim 10 (depends on 9) The method of claim 9, wherein the memory stores data specific to the motor vehicle, the data comprises at least one of a size of the motor vehicle, a size of the wheel of the motor vehicle, a size of a part of the motor vehicle, slip behavior of the wheel of the motor vehicle, a speed of the motor vehicle, and a radius of a curve. ### Claim 11 A position determination system for determining a current position of a motor vehicle, comprising: at least two sensor devices configured to measure a change in a wheel position for at least two wheels of the motor vehicle; a yaw rate sensor; and a calculating device configured to: determine a motion vector corresponding to the change in the wheel position for each wheel of the at least two wheels; generate an averaged motion vector based on the motion vector corresponding to the change in the wheel position for the each wheel; determine a yaw angle of the motor vehicle in response to a yaw rate provided by the yaw rate sensor; in response to the determined yaw angle of the motor vehicle, rotate the averaged motion vector by the determined yaw angle from the initial position. ### Claim 12 (depends on 11) The position determination system of claim 11, wherein the change in the wheel position for the at least two wheels is measured in a circumferential direction. ### Claim 13 (depends on 11) The position determination system of claim 11, wherein the calculation device is a control unit comprising a processor and a memory. ### Claim 14 (depends on 13) The position determination system of claim 13, wherein the memory stores data specific to the motor vehicle, the data comprises at least one of a size of the motor vehicle, a size of the wheel of the motor vehicle, a size of a part of the motor vehicle, slip behavior of the wheel of the motor vehicle, a speed of the motor vehicle, and a radius of a curve. ### Claim 15 (depends on 11) The position determination system of claim 11, wherein the calculating device is further configured to determine the motion vector based on a wheel steering angle or an Ackermann geometry of the motor vehicle. ### Claim 16 A motor vehicle, comprising: at least two sensor devices configured to measure a change in a wheel position for at least two wheels of the motor vehicle; a yaw rate sensor; and a calculating device for determining a current position of the motor vehicle, the calculating device configured to: determine a motion vector corresponding to the change in the wheel position for each wheel of the at least two wheels; generate an averaged motion vector based on the motion vector corresponding to the change in the wheel position for the each wheel; determine a yaw angle of the motor vehicle in response to a yaw rate provided by the yaw rate sensor; in response to the determined yaw angle of the motor vehicle, rotate the averaged motion vector by the determined yaw angle from the initial position. ### Claim 17 (depends on 16) The motor vehicle of claim 16, wherein the change in the wheel position for the at least two wheels is measured in a circumferential direction. ### Claim 18 (depends on 16) The motor vehicle of claim 16, wherein the calculation device is a control unit comprising a processor and a memory. ### Claim 19 (depends on 18) The motor vehicle of claim 18, wherein the memory stores data specific to the motor vehicle, the data comprises at least one of a size of the motor vehicle, a size of the wheel of the motor vehicle, a size of a part of the motor vehicle, slip behavior of the wheel of the motor vehicle, a speed of the motor vehicle, and a radius of a curve. ### Claim 20 (depends on 16) The motor vehicle of claim 16, wherein the calculating device is further configured to determine the motion vector based on a wheel steering angle or an Ackermann geometry of the motor vehicle.