Method for locating a user device related to a motor vehicle
By iteratively cross-referenced distances between objects and step distances, using the inertial measurement unit data of the smartphone, fast and accurate user positioning under the limited number of UWB communication modules is achieved, and the problems of inaccurate positioning and high cost in the prior art are solved.
Patent Information
- Application Number
- CN202411119516.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-09-12
- Filing Date
- 2024-08-15
- Publication Date
- 2025-03-14
AI Technical Summary
The prior art uses smartphones to communicate between vehicles and users, and it is difficult to achieve accurate and fast user positioning under a limited number of UWB communication modules, especially in multiple obstacles and complex environments.
By iteratively cross-referenced object distances and inter-step distances, the possible location area of the user equipment is gradually reduced by using the acceleration and orientation data provided by the inertial measurement unit of the user equipment until a single possible location area with a surface area smaller than the predefined surface area is determined.
It realizes rapid and accurate positioning of user equipment when vehicle users are approaching, reduces the demand for the number of UWB communication modules, reduces power consumption and wiring complexity, and improves the reliability and efficiency of the system.
Smart Images
Figure CN119620054A_ABST
Abstract
Description
[Technical field]
[0001] The present invention is in the field of motor vehicles and, more particularly, relates to a method for positioning a user equipment relative to a motor vehicle. [Background Technology]
[0002] As is known, today's vehicles include an access control system that makes it possible to activate a welcome function and a function for unlocking an opening element of the vehicle. For example, a function may include activating the vehicle's welcome lighting when a user moves within ten meters of the vehicle, or unlocking the opening element when the user is within two meters of the vehicle.
[0003] To this end, it is known that the vehicle includes communication modules (usually six to eight communication modules) and an electronic control unit for controlling these modules. Each module includes an antenna for sending and receiving signals to and from a device carried by the user (such as a key, a dedicated case or a smartphone).
[0004] A widely used technology for communication between a key or dedicated housing and the vehicle is based on radio frequency (RF) and low frequency (LF) signals. With this RF / LF technology, the user's position around the vehicle can be determined by triangulation using signal strength. However, the use of dedicated devices (keys or housings) is becoming less and less, and smartphones are replacing them.
[0005] In fact, smartphones, The emergence of the RFID and Ultra-Wideband (UWB) standards is pushing OEMs and manufacturers to implement these communications between the vehicle and the user directly via the user's smartphone, rather than via a key or dedicated device. In particular, smartphones typically do not have an RF / LF interface and are not easily accessible via the RFID reader. Or UWB to communicate faster, and can more easily use the signal. In addition, due to the attenuation of the signal, especially the attenuation of the signal caused by the user's body, using the signal strength to determine the location of the device carried by the user may not be accurate.
[0006] To at least partially address this problem, the UWB protocol makes it possible to determine the distance between each communication module and the smartphone using the signal's time of flight and triangulation.
[0007] However, regardless of the method used (signal strength or time of flight), locating a user around a vehicle requires the smartphone to communicate with at least three communication modules simultaneously in order to be able to accurately locate it through triangulation.
[0008] There are some solutions that attempt to at least partially compensate for this shortcoming. For example, when only two communication modules are communicating with the smartphone (the other modules cannot communicate with the smartphone due to obstacles or the distance between them), a known solution is to try to determine the possible and impossible positions of the smartphone. However, this determination is not always possible, so the position of the smartphone cannot be determined with certainty. When a single communication module is communicating with the smartphone (the other modules cannot communicate with the smartphone due to obstacles or the distance between them), a known solution includes using a satellite geolocation module (such as a GPS satellite geolocation module) so that the position of the smartphone on a circle centered on the communication module can be roughly determined. However, when the smartphone is in an area where satellite geolocation signals cannot be received (for example, inside a building or in a mountainous area outside the coverage area), this solution cannot be implemented.
[0009] An obvious solution that attempts to at least partially compensate for these shortcomings is to increase the number of UWB communication modules from, for example, six or eight to ten or twelve or more. However, this solution exhibits many disadvantages. First, each UWB communication module is particularly expensive, for example, about one hundred euros, and adding multiple modules will result in particularly high costs for vehicle manufacturers, which is generally unacceptable in the motor vehicle industry. Secondly, each UWB communication module consumes a lot of power, and this disadvantage becomes more and more significant as the number of UWB communication modules increases. In addition, each UWB communication module requires wiring to connect it to the vehicle's communication network and electronic control unit, but the space for such wiring in the vehicle is getting smaller and smaller, and such wiring may also cause problems during certification or even cause safety problems in the vehicle, especially when it is installed in the bumper. Finally, since the UWB communication module communicates with the smartphone in sequence, the more modules there are, the longer it takes to communicate with all the modules. However, the CCC standard limits this time to 96ms, and for example, using twelve UWB communication modules will result in a time of about one and a half seconds, which is unacceptable.
[0010] Therefore, a simple, reliable and effective solution for at least partially remedy these drawbacks, in particular a solution making it possible to limit the number of UWB communication modules, would be advantageous. [Summary of the invention]
[0011] To this end, a first subject of the invention is a method for positioning a user device relative to a motor vehicle, said vehicle comprising an electronic control unit and a plurality of ultra-wideband communication modules, said user device carried by a user comprising an inertial measurement unit configured to provide acceleration and orientation data about said user device and an ultra-wideband communication module configured to communicate with each ultra-wideband communication module of the vehicle, said method comprising the following steps iteratively performed while the user is in motion:
[0012] - exchanging ultra-wideband signals between at least one ultra-wideband communication module of the vehicle and an ultra-wideband communication module of the user equipment,
[0013] - determining the so-called "inter-object" distance between said at least one ultra-wideband communication module of the vehicle and the user equipment based on the flight time of the exchanged signals,
[0014] -Measure the acceleration and orientation of the user's device,
[0015] - calculating the distance covered by the user between two consecutive steps, the so-called "steps", based on the measured acceleration and orientation values,
[0016] - cross-referencing the determined inter-object distances and the calculated inter-step distances in order to determine at least one possible location area of the user equipment,
[0017] The iteration ends when a single possible location area of the user equipment having a surface area smaller than the predefined surface area is determined, the single possible location area corresponding to the location of the user equipment around the vehicle.
[0018] The method according to the invention makes it possible to accurately and quickly locate users of a vehicle as they approach said vehicle. In fact, a few steps taken by the user towards the vehicle are sufficient to determine, in the same number of iterations of the method, a series of possible location zones of the user device (and therefore the user), which are reduced until a single zone is obtained whose surface area is small enough to determine the exact location of the user device.
[0019] According to one aspect of the invention, cross-referencing includes determining a possible position of the user device in terms of inter-object distances and inter-step distances.
[0020] In one embodiment, the number of iterations is at least equal to four, for example, equal to five or six.
[0021] The invention also relates to a computer program product, characterized in that the computer program product comprises a set of program code instructions which, when executed by one or more processors, configure the one or more processors to implement the method as described above.
[0022] The present invention also relates to a user equipment, which is configured to implement the method as described above, and the user equipment is further configured to send the position determined after iteration to the vehicle.
[0023] The invention also relates to an electronic control unit for a motor vehicle, the electronic control unit being configured as follows:
[0024] - determining a so-called “inter-object” distance between at least one ultra-wideband communication module of the vehicle and an ultra-wideband communication module of a user device carried by a user based on the flight time of ultra-wideband signals exchanged between said at least one ultra-wideband communication module of the vehicle and said user device,
[0025] - receiving acceleration values and orientation values sent by the user device,
[0026] - calculating the distance covered by the user between two consecutive steps, the so-called "steps", based on the measured acceleration and orientation values,
[0027] - cross-referencing the determined inter-object distances and the calculated inter-step distances in order to determine at least one possible location area of the user equipment,
[0028] - When a single possible location area of the user equipment is determined having a surface area smaller than the predefined surface area, determining the location of the user equipment around the vehicle.
[0029] According to one aspect of the invention, the electronic control unit is configured to determine a possible position of the user device in terms of the inter-object distance and the inter-step distance during the cross-referencing.
[0030] In one embodiment, the electronic control unit is configured to perform at least four iterations, preferably five or six iterations, of the method as described above.
[0031] The invention also relates to a motor vehicle comprising a plurality of ultra-wideband communication modules and an electronic control unit as described above.
[0032] The present invention also relates to a communication system comprising a vehicle and a user device, the vehicle comprising an electronic control unit and a plurality of ultra-wideband communication modules, the user device comprising an inertial measurement unit configured to provide acceleration and orientation data about the user device and an ultra-wideband communication module configured to communicate with each ultra-wideband communication module of the vehicle, the vehicle and the user device being configured to implement the method as described above, except that the steps of measuring the acceleration value and orientation value of the user device are always performed by the user device, and these steps are distributed between the vehicle and the user device in any way.
[0033] The present invention also relates to a communication system comprising a vehicle as described above and a user device, the user device comprising an inertial measurement unit configured to provide acceleration and orientation data related to the user device and an ultra-wideband communication module configured to communicate with each ultra-wideband communication module of the vehicle. [Drawings]
[0034] Other features and advantages of the present invention will become more apparent upon reading the following description. This description is purely illustrative and should be read with reference to the accompanying drawings, in which:
[0035] [ Figure 1 ] Figure 1 An embodiment of the system according to the invention is schematically illustrated.
[0036] [ Figure 2 ] Figure 2 Schematically shows Figure 1 User equipment of the system.
[0037] [ Figure 3 ] Figure 3 A first exemplary embodiment of the method according to the invention is schematically illustrated.
[0038] [ Figure 4 ] Figure 4 A second embodiment of the method according to the invention is schematically illustrated.
[0039] [ Figure 5 ] Figure 5 An exemplary embodiment of the method according to the invention in a first iteration is shown.
[0040] [ Figure 6 ] Figure 6 An exemplary embodiment of the method according to the invention in a second iteration is presented.
[0041] [ Figure 7 ] Figure 7 An exemplary embodiment of the method according to the invention in a third iteration is presented.
[0042] [ Figure 8 ] Figure 8 An exemplary embodiment of the method according to the invention in a fourth iteration is presented.
[0043] [ Fig. 9 ] Fig. 9 An exemplary embodiment of the method according to the invention in a fifth iteration is shown.
[0044] [ Fig.10 ] Fig.10An exemplary implementation of the method according to the invention in a sixth iteration is presented.
[0045] [ Fig.11 ] Fig.11 An exemplary embodiment of the method according to the invention in the seventh iteration is shown.
[0046] [ Fig.12 ] Fig.12 An exemplary embodiment of the method according to the invention in an eighth iteration is shown.
[0047] [ Fig.13 ] Fig.13 An exemplary implementation of the method according to the invention in a ninth iteration is shown.
[0048] [ Fig.14 ] Fig.14 An exemplary implementation of the method according to the invention in the tenth iteration is shown. [Specific implementation method]
[0049] Figure 1 An example of a system 1 according to the invention is shown.
[0050] The system 1 includes a vehicle 10 and a user device 20 carried by a user 21 .
[0051] The vehicle 10 includes an electronic control unit 110 and a plurality of ultra-wideband communication modules 120 .
[0052] refer to Figure 2 The user device 20 includes an inertial measurement unit 210 configured to provide acceleration and orientation data related to the user device 20 and an ultra-wideband communication module 220 configured to communicate with each ultra-wideband communication module 120 of the vehicle 10.
[0053] First embodiment
[0054] In this first embodiment, the electronic control unit 110 is configured to determine the so-called “inter-object” distance between at least one of the ultra-wideband communication modules 120 of the vehicle 10 and the user device 20 based on the flight time of the ultra-wideband signal exchanged between the at least one ultra-wideband communication module 120 of the vehicle 10 and the ultra-wideband communication module 220 of the user device 20.
[0055] In this first embodiment, the user device 20 is configured to send measured acceleration values and orientation values to the electronic control unit 110 , and the electronic control unit 110 is configured to receive the acceleration values and orientation values sent by the user device 10 .
[0056] In this first embodiment, the electronic control unit 110 is configured to calculate the so-called “inter-step” distance covered by the user 21 between two consecutive steps based on the received acceleration values and orientation values.
[0057] In this first embodiment, the electronic control unit 110 is configured to cross-reference the determined inter-object distance and the calculated inter-step distance in order to determine at least one possible location area of the user device 20. To this end, the electronic control unit 110 is configured to determine the possible location of the user device 10 on the inter-object distance and the inter-step distance during the cross-referencing.
[0058] The electronic control unit is configured to perform a number of iterations of the above determination and calculation, the same number as the number of steps of the user 21 , so as to be able to determine the position of said user 21 , preferably at least four iterations, more preferably five or six iterations.
[0059] In this first embodiment, the electronic control unit 110 is configured to determine the location of the user device 20 around the vehicle 10 when a single possible location area of the user device 10 having a surface area smaller than a predefined surface area is determined.
[0060] The electronic control unit 110 includes a processor capable of executing a set of instructions for performing these functions.
[0061] Second embodiment
[0062] In the second embodiment, the user device 20 is configured to exchange ultra-wideband signals with at least one of the ultra-wideband communication modules 120 of the vehicle 10 via the ultra-wideband communication module 220 .
[0063] In this second embodiment, the user device 20 is configured to receive a so-called “inter-object” distance between the at least one ultra-wideband communication module 120 of the vehicle 10 and the user device 20 calculated by the electronic control unit 110 based on the flight times of the exchanged signals.
[0064] In the second embodiment, the user device 20 is configured to measure acceleration values and orientation values of the user device when the user 21 moves with the user device 20 .
[0065] In this second embodiment, the user device 20 is configured to calculate the so-called "inter-step" distance covered by the user 21 between two consecutive steps based on the measured acceleration values and orientation values.
[0066] In this second embodiment, the user device 20 is configured to cross-reference the determined inter-object distance and the calculated inter-step distance in order to determine at least one possible location area of the user device 20 .
[0067] In this second embodiment, the user device 20 is configured to perform the above determination and calculation iterations, the same number of times as the number of steps of the user 21, so as to be able to determine the position of the user 21, preferably at least four iterations, more preferably five or six iterations.
[0068] The iteration ends when the user device 20 determines a single possible location area of the user device having a surface area smaller than the predefined surface area, the single possible location area corresponding to the location of the user device 20 around the vehicle 10 .
[0069] In this second embodiment, the user device 20 is configured to send the position determined after the iteration to the vehicle 10 .
[0070] Exemplary Embodiments
[0071] First Exemplary Embodiment
[0072] This first example implements the first embodiment and refers to Figure 3 Give a description.
[0073] In this example, the user approaches a corner of the vehicle 10 so that they can only see one ultra-wideband communication module 120 of the vehicle 10, that is, they can only communicate with this one ultra-wideband communication module. When the ultra-wideband communication module 120 of the vehicle 10 within the visible range detects the user device 20, the method starts the first iteration.
[0074] Therefore, in step E1 , the ultra-wideband communication module 220 of the user device 20 first exchanges ultra-wideband signals with the single ultra-wideband communication module 120 of the vehicle 10 within the visible range.
[0075] Then, in step E2, the electronic control unit 110 determines the inter-object distance DIO between the ultra-wideband communication module 120 within the visible range of the vehicle 10 and the user device 20, for example periodically, based on the flight time of the exchanged signals, and then in step E3, the determined inter-object distance is sent to the user device 20 via the ultra-wideband communication module 120 within the visible range of the vehicle 10.
[0076] In step E4 , the inertial measurement unit 210 of the user device 20 measures acceleration and orientation values of the user device 20 when the user 21 moves, and then in step E5 , sends the measurement values to the electronic control unit 110 via the ultra-wideband communication module 120 within the visible range of the vehicle 10 .
[0077] Then, in step E6, the electronic control unit 110 calculates the step-to-step distance DIP traveled by the user 21 between two consecutive steps based on the received acceleration value and orientation value, and then in step E7, cross-references the determined object-to-object distance DIO and the calculated step-to-step distance DIP to determine at least one possible location zone ZLP of the user device 20.
[0078] Steps E1 to E7 are repeated until the electronic control unit 110 determines a single possible location zone ZLP having a surface area smaller than the predefined surface area and corresponding to the location of the user device 20 around the vehicle 10 .
[0079] Second Exemplary Embodiment
[0080] This second example implements the second embodiment and refers to Figure 4 Give a description.
[0081] In this example, as in the previous example, the user approaches a corner of the vehicle 10 so that they can only see one ultra-wideband communication module 120 of the vehicle 10, that is, so that they can only communicate with this one ultra-wideband communication module. When the ultra-wideband communication module 120 of the vehicle 10 within the visible range detects the user device 20, the method starts the first iteration.
[0082] Therefore, in step F1 , the ultra-wideband communication module 220 of the user device 20 first exchanges ultra-wideband signals with the single ultra-wideband communication module 120 of the vehicle 10 within the visible range.
[0083] Then, in step F2, the electronic control unit 110 determines the inter-object distance DIO between the ultra-wideband communication module 120 in the visible range of the vehicle 10 and the user device 20, for example, periodically, based on the flight time of the exchanged signal, and then in step F3, the determined inter-object distance DIO is sent to the user device 20 via the ultra-wideband communication module 120 in the visible range of the vehicle 10. As a variant, the user device 20 may determine the inter-object distance in step F2, for example, periodically, and there is no sending step F3.
[0084] Next, in step F4 , the inertial measurement unit 210 of the user device 20 measures acceleration values and orientation values of the user device 20 when the user 21 moves.
[0085] Then, in step F5, the user device 20 calculates the step-to-step distance DIP traveled by the user 21 between two consecutive steps based on the received acceleration value and orientation value, and then in step F6, cross-references the determined object-to-object distance DIO and the calculated step-to-step distance DIP to determine at least one possible location zone ZLP of the user device 20.
[0086] Steps F1 to F6 are repeated until the user device 20 determines a single possible location zone ZLP having a surface area smaller than the predefined surface area and corresponding to the location of said user device 20 around the vehicle 10 .
[0087] It should be noted that, in addition to measuring the acceleration value and orientation value of the user device 20, the steps of the method according to the present invention can be implemented by the electronic control unit 110 or the user device 20. Therefore, the present invention also covers other embodiments whose steps are partially implemented by the electronic control unit 110 and partially implemented by the user device 20 and are different from the two examples given above.
[0088] Simulation Example
[0089] Figures 5 to 14 An example of determining the position of a user device 20 during the first ten iterations of the method according to the invention is depicted in the form of a two-dimensional geographical map seen from above. The dimensions of the map are in meters.
[0090] The ultra-wideband communication module 120 of the vehicle 10 is represented by a white star. The user device 20 is represented by a disk. The trajectory of the user device is represented by the lines on the disk. The possible location zone ZLP is shown in light gray. The background of the map (the area outside the possible location zone ZLP) is shown in black.
[0091] In the first iteration ( Figure 5 ), it is determined that the user equipment 20 is located at a given distance from the ultra-wideband communication module 120. Therefore, its possible location zone ZLP is in the form of a circle, and the thickness of the circle represents the measurement tolerance (uncertainty about the measurement distance).
[0092] In the second iteration ( Figure 6 ), the user 21 takes a step and therefore knowing their step length and the orientation (direction of movement) of the user device 20, the method makes it possible to reduce the possible location zones ZLP to different areas corresponding to arcs of a circle.
[0093] The third iteration ( Figure 7 ) makes it possible to reduce the possible location zone ZLP after the user 21 takes an additional step to two different areas corresponding to two arc portions of a circle, the total surface area of which is smaller than the surface area of the possible location zone ZLP determined in the previous iteration.
[0094] The fourth iteration ( Figure 8) makes it possible to further reduce the possible location zone ZLP after the user 21 has taken an additional step, in this example again to two different areas corresponding to two arc portions of a circle, the total surface area of which is smaller than the surface area of the possible location zone ZLP determined in the previous iteration.
[0095] The fifth iteration ( Fig. 9 ) makes it possible to reduce the possible location zones ZLP to a single possible location zone ZLP after the user 21 takes an additional step and changes direction, where the surface area of the single possible location zone ZLP is substantially equal to the surface area of one of the areas obtained in the previous iteration and is smaller than a predefined surface area corresponding to the position of the user device 20 around the vehicle 10.
[0096] The sixth, seventh, eighth, ninth, and tenth iterations ( Figures 10 to 14 ) makes it possible to further refine the surface area of the possible location zone ZLP after the user 21 takes an additional step, so as to improve the positioning accuracy of the user device 20 along its trajectory.
[0097] Therefore, the present invention makes it possible to quickly, reliably and efficiently determine the position of the user device 20 relative to the vehicle 10, that is, its position around the vehicle 10, by using the trajectory followed by the user device 20 and the distance between the vehicle 10 and the user device 20.
Claims
1. A method for locating a user device (20) relative to a motor vehicle (10), the vehicle (10) comprising an electronic control unit (110) and a plurality of ultra-wideband communication modules (120), the user device (20) carried by a user (21) comprising an inertial measurement unit (210) configured to provide acceleration and orientation data about the user device (20) and an ultra-wideband communication module (220) configured to communicate with each ultra-wideband communication module (120) of the vehicle (10), the method comprising the following steps iteratively performed while the user (21) is in motion: - exchanging (E1, F1) ultra-wideband signals between at least one ultra-wideband communication module (120) of the vehicle (10) and an ultra-wideband communication module (220) of the user equipment (20), - determining (E2, F2) a so-called "inter-object" distance (DIO) between said at least one ultra-wideband communication module (120) of the vehicle (10) and the user equipment (20) based on the flight time of the exchanged signals, - measuring (E4, F4) the acceleration value and the orientation value of the user equipment (20), - calculating (E6, F5) the so-called "inter-step" distance (DIP) covered by the user (21) between two consecutive steps based on the measured acceleration values and orientation values, - Cross-reference (E7, F6) the determined inter-object distance (DIO) and the calculated inter-step distance (DIP) to determine at least one possible location zone (ZLP) of the user device (20), the iteration ending when a single possible location zone (ZLP) of the user device (20) having a surface area smaller than a predefined surface area is determined, and the single possible location zone (ZLP) corresponds to the position of the user device (20) around the vehicle (10).
2. The method of claim 1, wherein: The cross-referencing includes determining a possible position of the user device (20) in terms of the distance between objects (DIO) and the distance between steps (DIP).
3. A method as claimed in any one of the preceding claims, wherein: The number of iterations is at least equal to four, for example, equal to five or six.
4. A computer program product, characterized in that The computer program product comprises a set of program code instructions which, when executed by one or more processors, configure the one or more processors to implement the method as claimed in any one of the preceding claims.
5. A user device (20) configured to implement the method according to any one of claims 1 to 3, the user device (20) being further configured to send the position determined after iteration to the vehicle (10).
6. An electronic control unit (110) for a motor vehicle (10), the electronic control unit (110) being configured to: - determining a so-called "inter-object" distance (DIO) between at least one ultra-wideband communication module (120) of the vehicle (10) and the user device (20) carried by the user (21) based on the flight time of ultra-wideband signals exchanged between the at least one ultra-wideband communication module (120) of the vehicle (10) and the ultra-wideband communication module (220) of the user device (20), - receiving acceleration values and orientation values sent by the user device (20), - calculating the so-called "inter-step" distance (DIP) covered by the user (21) between two consecutive steps based on the measured acceleration values and orientation values, - cross-referencing the determined distance between objects (DIO) and the calculated distance between steps (DIP) in order to determine at least one possible location zone (ZLP) of the user equipment (20), - When a single zone of possible location (ZLP) having a surface area smaller than a predefined surface area is determined, determining the location of the user device (20) around the vehicle (10).
7. The electronic control unit (110) according to the preceding claim, being configured to determine during cross-referencing a possible position of the user device (20) on the inter-object distance (DIO) and the inter-step distance (DIP).
8. The electronic control unit (110) according to the preceding claim, configured to perform at least four iterations, preferably five or six iterations, of the method according to any one of claims 1 to 3.
9. A motor vehicle (10) comprising a plurality of ultra-wideband communication modules (120) and an electronic control unit (110) according to any one of claims 6 to 8.
10. A communication system (1) comprising a vehicle (10) as claimed in the preceding claim and a user device (20), the user device comprising an inertial measurement unit (210) configured to provide acceleration and orientation data about the user device (20) and an ultra-wideband communication module (220) configured to communicate with each ultra-wideband communication module (120) of the vehicle (10).