Method and device for controlling the speed of a vehicle at an intersection

Abstract

The present invention relates to a method and device for controlling the speed of a vehicle (10) traveling on a first section of road (101) in a road environment (1). To this end, data representing an intersection between the first section of road and second sections of road (102, 103) are received. This data includes a distance value between the vehicle's position and the intersection and an angle value between the first section of road and each second section of road. A threshold distance value is determined, and a speed value is determined for each second section of road. A first speed is then checked. Data representing the steering angle variation are received, a second section of road is selected, and a second vehicle speed corresponding to the speed value associated with the selected second section of road is checked. (See Figure 1 for abbreviations.)

Description

Title of the invention: Method and device for controlling the speed of a vehicle in an intersection Technical field

[0001] The present invention relates to methods and devices for controlling the speed of a vehicle in an intersection, in particular a motor vehicle. The present invention also relates to a method and a device for controlling a driving assistance system on board a vehicle. The present invention also relates to a method and a device for controlling a vehicle carrying one or more driving assistance systems, in particular an autonomous vehicle. Technological background

[0002] Road safety is one of the major challenges facing our societies. With the increasing number of vehicles on the world's road networks, regardless of traffic conditions, the risk of accidents and incidents caused by traffic conditions has never been greater.

[0003] To improve road safety, some contemporary vehicles are equipped with driver assistance functions or systems, known as AD AS (from the English "Advanced Driver-Assistance System" or in French "Advanced Driving Assistance System"). AD AS systems, for example, implement methods based on knowledge of the road environment in which the vehicle is traveling. Knowledge of this environment is, for example, obtained from environmental mapping data received, for example, from a remote device of the server type via a wireless communication network, as the vehicle moves.

[0004] This mapping data includes in particular data on the intersection(s) located on the path of the vehicle, this intersection data being used by one or more AD AS systems, for example to control the speed of the vehicle approaching an intersection.

[0005] Incorrect interpretation of intersection data by the vehicle and / or poor anticipation of the vehicle's path leads to risks of malfunction of the ADAS system(s) using this data, with a safety risk for the vehicle and its passengers. Summary of the present invention

[0006] An object of the present invention is to solve at least one of the problems of the technological background described above.

[0007] Another object of the present invention is to improve the operation of a vehicle driving assistance system.

[0008] Another object of the present invention is to improve the control of a vehicle speed in an intersection.

[0009] According to a first aspect, the present invention relates to a method for controlling a speed of a vehicle in an intersection, the vehicle traveling on a first portion of road in a road environment, the method comprising the following steps: - receiving intersection data representative of an intersection between the first road portion and a set of second road portions located downstream of a current position of the vehicle, the intersection data comprising for each second road portion: • a distance value between the current position of the vehicle and the intersection between the first section of road and each second section of road, and • an angle value between the first portion of road and each second portion of road, the same distance value being associated with a plurality of second road portions of the set, a second road portion, called a continuation, of the plurality of second road portions being identified in the intersection data as corresponding to a continuity of the first road portion; - determination of information representative of a threshold distance associated with the intersection and, for each second section of road, of a speed value, based on the intersection data; - control of a first vehicle speed corresponding to the speed value associated with the second portion of continuation road; - reception of directional data representative of a direction of a variation of a steering angle of the vehicle when a distance separating the vehicle from the intersection is less than or equal to the threshold distance; - selecting a second road portion from among the plurality of second road portions based on the intersection data and the directional data; and - control of a second vehicle speed corresponding to the speed value associated with the second selected section of road.

[0010] Such a method makes it possible to define a first speed of the vehicle when it approaches an intersection and, once the second portion of road to be taken has been selected, to define a second speed suitable for taking this second portion of road in complete safety.

[0011] According to a method variant, the steps of determining the information representative of a threshold distance and the speed values, of controlling the first speed, directional data reception and second speed control are implemented only when an absolute value of each angle value is less than a value of a limit angle.

[0012] These steps listed above are thus implemented when the values ​​of the angles formed between the second road portions and the first road portion are small, that is to say less than a limiting angle.

[0013] According to another method variant, the limit angle value is equal to 25°.

[0014] According to another method variant, when the plurality of second portions of road includes two second road sections, an intersection between the first road section and the two second road sections corresponds to a Y-shaped intersection.

[0015] Such an intersection shape is very recognizable.

[0016] According to an additional method variant, the first and second speed controls are implemented by a predictive adaptive cruise control system, called a P-ACC system. Such a driving assistance system is commonly installed in recent vehicles.

[0017] According to yet another method variant, the intersection data are cartographic data.

[0018] Many maps are now available and accessible, they have precise data on the different sections of roads and intersections.

[0019] According to a second aspect, the present invention relates to a device for controlling the speed of a vehicle in an intersection, the device comprising a memory associated with a processor configured for implementing the steps of the method according to the first aspect of the present invention.

[0020] According to a third aspect, the present invention relates to a vehicle, for example of the automobile type, comprising a device as described above according to the second aspect of the present invention.

[0021] According to a fourth aspect, the present invention relates to a computer program which comprises instructions adapted for executing the steps of the method according to the first aspect of the present invention, in particular when the computer program is executed by at least one processor.

[0022] Such a computer program may use any programming language, and be in the form of source code, object code, or intermediate code between source code and object code, such as in a partially compiled form, or in any other desirable form.

[0023] According to a fifth aspect, the present invention relates to a computer-readable recording medium on which is recorded a computer program comprising instructions for carrying out the steps of the method according to the first aspect of the present invention.

[0024] On the one hand, the recording medium may be any entity or device capable of storing the program. For example, the medium may comprise a storage means, such as a ROM memory, a CD-ROM or a microelectronic circuit type ROM memory, or a magnetic recording means or a hard disk.

[0025] Furthermore, this recording medium may also be a transmissible medium such as an electrical or optical signal, such a signal being able to be conveyed via an electrical or optical cable, by conventional or hertzian radio or by self-directed laser beam or by other means. The computer program according to the present invention may in particular be downloaded from an Internet-type network.

[0026] Alternatively, the recording medium may be an integrated circuit in which the computer program is incorporated, the integrated circuit being adapted to perform or to be used in performing the method in question. Brief description of the figures

[0027] Other characteristics and advantages of the present invention will emerge from the description of the particular and non-limiting exemplary embodiments of the present invention below, with reference to the appended figures 1 to 3, in which:

[0028] [Fig-1] schematically illustrates an environment 1 in which a vehicle evolves, according to a particular and non-limiting exemplary embodiment of the present invention;

[0029] [Fig.2] schematically illustrates a device configured to control a speed of the vehicle of [Fig.l] in an intersection, according to a particular and non-limiting exemplary embodiment of the present invention;

[0030] [Fig.3] illustrates a flowchart of the different stages of a control process of a speed of the vehicle of [Fig.l] in an intersection, according to a particular and non-limiting exemplary embodiment of the present invention. Description of examples of implementation

[0031] A method and a device for controlling a vehicle path will now be described in the following with joint reference to Figures 1 to 3. The same elements are identified with the same reference signs throughout the description which follows.

[0032] The terms "first(s)", "second(s)" (or "first(s)", "second(s)"), etc. are used in this document by arbitrary convention to enable different elements (such as operations, means, etc.) implemented in the embodiments described below to be identified and distinguished. Such elements may be distinct or correspond to a single element, depending on the embodiment.

[0033] According to a particular and non-limiting example of embodiment of the present invention, controlling a speed of a vehicle in an intersection, for example by a computer of the vehicle, the vehicle traveling on a first portion of road of a road environment, comprises receiving intersection data representative of an intersection between the first portion of road and a set of second portions of road located downstream of a current position of the vehicle. The intersection data comprises, for each second portion of road, a distance value between the current position of the vehicle and the intersection between the first portion of road and each second portion of road, and an angle value between the first portion of road and each second portion of road, the same distance value being associated with a plurality of second portions of road of the set.A second road portion, called a continuation, of the plurality of second road portions is identified in the intersection data as corresponding to a continuation of the first road portion.

[0034] Depending on the intersection data, information representative of a threshold distance associated with the intersection is determined and, for each second portion of road, a speed value is also determined.

[0035] The vehicle speed is controlled to be equal to a first speed corresponding to the speed value associated with the second portion of continuation road.

[0036] Directional data representative of a direction of a variation of a steering angle of the vehicle are received when a distance separating the vehicle from the intersection is less than or equal to the threshold distance.

[0037] A second road portion is then selected from the plurality of second road portions based on the intersection data and the directional data. The vehicle speed is controlled to be equal to a second speed corresponding to the speed value associated with the selected second road portion.

[0038] [Fig. 1] schematically illustrates an environment 1 in which a vehicle operates, according to a particular and non-limiting exemplary embodiment of the present invention.

[0039] The vehicle 10 corresponds for example to a motor vehicle moving in a road environment 1 comprising one or more roads or portions of road.

[0040] The vehicle 10 corresponds for example to a vehicle with a thermal engine, with electric motor(s) or even a hybrid vehicle with a thermal engine and one or more electric motors. The vehicle 10 thus corresponds for example to a coach, a bus, a truck, a utility vehicle or a motorcycle, that is to say to a vehicle of the motorized land vehicle type.

[0041] The vehicle 10 corresponds for example to a vehicle traveling in an autonomous or semi-autonomous mode. The vehicle travels for example according to a level autonomy greater than or equal to 2, according to the scale defined by the American federal agency which has established 5 levels of autonomy ranging from 1 to 5, level 0 corresponding to a vehicle with no autonomy, the driving of which is under the total supervision of the driver, level 1 corresponding to a vehicle with a minimal level of autonomy, the driving of which is under the supervision of the driver with minimal assistance from an AD AS system, and level 5 corresponding to a completely autonomous vehicle.

[0042] The vehicle 10 has one or more driving assistance systems, called AD AS (from the English “Advanced Driver-Assistance System” or in French “Advanced Driving Assistance System”). Such AD AS systems are configured to assist, or even replace, the driver of the vehicle 10 to control the vehicle 10 on its journey.

[0043] The vehicle 10 for example carries one or more of the following AD AS systems for this purpose: - adaptive cruise control system, known as ACC (from the English “Adaptive Cruise Control”), - predictive cruise control, known as the P-ACC system (from the English "Predictive-Adaptive Cruise Control"), - intelligent speed adaptation system, known as ISA system (from English “Intelligent Speed ​​Adaptation”), - curve speed adaptation system, known as CSA system (from the English “Curve Speed ​​Assist”), - electronic stability control system, known as ESC (Electronic Stability Control), DSC (Dynamic Stability Control) or ESP (Electronic Stability Program), - lane keeping assistance system, known as LKA (Lane-Keeping Assist) or LPA (Lane Positioning Assist), - semi-automatic lane change system, known as SALC (Semi Automatic Lane Change) system, and / or - object detection system, called ODS system (from the English “Object Detection System”).

[0044] The examples of AD AS systems in the list above are provided for illustrative purposes and are not limiting, this list not being exhaustive.

[0045] The AD AS systems on board the vehicle 10 are for example supplied with data obtained from one or more on-board sensors, such as for example radars, LIDARs and / or cameras, and / or data received from a communications infrastructure.

[0046] According to a particular exemplary embodiment, the vehicle 10 carries a communication system configured to communicate with one or more remote devices 111 via a wireless communication network infrastructure. The remote device 111 corresponds for example to a server of the “cloud” 100 (or “cloud” in French). The wireless communication infrastructure comprises for example a set of communication devices 110 of the cellular network antenna type of the LTE 4G or 5G type or of the UBR (Roadside Unit) type.

[0047] The communication system of the vehicle 10 comprises, for example, one or more communication antennas connected to a telematic control unit, called TCU (from the English “Telematic Control Unit”), itself connected to one or more computers of the on-board system of the vehicle 10, in particular one or more computers responsible for controlling the AD AS systems of the vehicle 10. The antenna(s), the TCU unit and the computer(s) form, for example, a multiplexed architecture for the realization of different services useful for the proper functioning of the vehicle and for assisting the driver and / or the passengers of the vehicle in the control of the vehicle 10.The computer(s) and the TCU communicate and exchange data with each other via one or more computer buses, for example a communication bus of the CAN (Controller Area Network), CAN FD (Controller Area Network Flexible Data-Rate), FlexRay (according to the ISO 17458 standard) or Ethernet (according to the ISO / IEC 802-3 standard) data bus type.

[0048] The wireless communication system allowing the exchange of data between the vehicle 10 and the remote device(s) 111 corresponds for example to: - a vehicle-to-infrastructure (V2I) communication system, for example based on the 3GPP LTE-V or IEEE 802.1 Ip standards of ITS G5; or - a cellular network type communication system, for example an LTE (Long-Term Evolution), LTE-Advanced, LTE 4G or 5G type network; or - a Wifi type communication system according to IEEE 802.11, for example according to IEEE 802.1 In or IEEE 802.1 lac.

[0049] According to another particular example of embodiment, the vehicle 10 carries a receiver of a satellite geolocation system of the GPS type (from the English “Global Positioning System” or in French “Système mondial de positioning”) or the Galileo system for example in communication with a computer of the system. on-board vehicle 10. The satellite geolocation system is, for example, associated with mapping.

[0050] The mapping comprises, for example, a road map in which the roads constituting the road network on which the vehicle 10 is traveling are located and referenced. This road map comprises different sections or different portions of roads and connections between these different portions called intersections, as well as, for example, topological, geometric, regulatory information such as speed limits or priority and event regimes.

[0051] The road environment 1 comprises for example a first portion of road 101 on which the vehicle 10 is traveling at a current time, the first portion of road 101 opening onto a set of second portions of road 102, 103, the second portions of road 102, 103 forming a new intersection with the first portion of road 101.

[0052] For example, road portions 101, 102 and 103 form a Y-shaped intersection, with the first road portion 101 forming a first vertical leg of the Y, and the second road portions 102 and 103 forming the second and third inclined legs of the Y.

[0053] The vehicle 10 traveling on the first portion of road 101 can thus take the second portion of road 102 furthest to the left (depending on the direction of travel of the vehicle 10) or the second portion of road 103 furthest to the right (depending on the direction of travel of the vehicle 10).

[0054] Mapping data (or cartographic data) are advantageously received by the vehicle 10, for example as the vehicle 10 moves.

[0055] The map data of the environment 1 are received, for example via a wireless link from the server 111 via the wireless communication infrastructure and the wireless communication system of the vehicle 10.

[0056] These data are for example received as the vehicle 10 moves according to a V2X (Vehicle-to-Everything) communication mode, for example according to an I2V (Infrastructure-to-Vehicle) mode.

[0057] The received mapping data advantageously comprises data representative of the upcoming intersections within a determined horizon (for example for each intersection included in a distance interval equal to 1000, 1500, 2000 or 2500 m starting from the position of the vehicle 10 at the time of reception of the mapping data).

[0058] The intersection data includes for example for each intersection: - a distance value between the current position of the vehicle 10 (at the time of reception of mapping data) and intersection; - an angle value between the first portion of road 101 and the second portion of road 102, 103; and optionally - identification information (ID) of the type of the second section of road, such information identifying for example the sections of road known as continuation sections with a determined identifier (for example a value equal to 6), the other sections of road being identified with a different identifier (for example a value equal to 5).

[0059] A portion of road is said to be a continuation when it is considered that this portion of road forms a continuity of another portion of road.

[0060] Such a continuation qualification is for example determined by an operator entering the data into a database associated with the server 111, based on the observed traffic habits (the continuation road portion corresponding for example to the most used portion following the road portion which precedes it and of which it forms the continuity).

[0061] The intersection data are for example received in the form of a table such as table 1 below, giving the distance information relative to the vehicle 10 traveling on the first portion of road 101.

[0062] [Tables 1] Portion 102 Portion 103 Portion 104 Portion 105 Distance 100 100 250 250 Angle -6° 20° 95° 0° ID 6 5 5 6

[0063] The mapping data comprising the intersection data are for example received automatically at regular intervals (for example every 100, 200, 500 ms) or at the request of the vehicle 10. The mapping data are for example received after transmission by the vehicle 10 to the server 111 of current position data of the vehicle 10, for example obtained from the geolocation system on board the vehicle 10.

[0064] The distance between the vehicle 10 and the intersection(s) is for example updated by the vehicle 10 between two consecutive receptions of the intersection data, from the dynamic data of the vehicle 10 (for example the speed which makes it possible to determine the distance traveled by measuring the elapsed time) and / or from the position data of the vehicle 10 obtained from the geolocation system on board the vehicle 10.

[0065] An example of a problem that arises is to precisely define the second portion of road that the vehicle 10 will take. Indeed, 1TD statistically defines the second most likely section of road to be taken, called MPP (from the English “Most Probable Path”), however the direction that vehicle 10 will take is not certain.

[0066] This uncertainty is all the more significant as the values ​​of the angles formed by the directions of the first portion of road 101 and the second portions of road 102, 103 are small.

[0067] The manifestation of taking such or such road is for example identified or determined via the detection of the indicators of the vehicle 10, but the latter are not systematically activated when the direction of a second portion of road is close to the direction of the first portion of road 101.

[0068] Depending on the second portion of road taken, the speed of the vehicle 10 in the intersection is different. The wrong portion of road identified can then lead to an error in the control, for example an erroneous speed control when the AD AS system corresponds to a P-ACC type system.

[0069] The control process below provides a solution to this problem in particular.

[0070] A process for controlling a speed of the vehicle 10 in an intersection is advanced efficiently implemented by the vehicle 10, for example by one or more processors of one or more computers on board the vehicle 10.

[0071] In a first operation, intersection data is received by the vehicle 10, this data corresponding for example to the data of Table 1 received at a current time according to a wireless connection, as described above for example.

[0072] The second portions of road 102, 103 are located downstream of a current position of the vehicle 10, the current position of the vehicle 10 being for example obtained via a satellite geolocation system.

[0073] The intersection data advantageously comprise, for each second portion of road 102, 103 identified within a distance horizon determined from the current position of the vehicle 10: - a distance value between the current position of the vehicle 10 and the intersection between the first portion of road 101 and each second portion of road 102, 103, and - an angle value between said first portion of road 101 and each second portion of road 102, 103.

[0074] The same distance value is associated with at least 2 second road portions, i.e. road portions 102, 103 according to the particular example of [Fig.l], a second road portion 102 called continuation being identified in the intersection data, for example with a determined identifier (the value 6 according to the particular example of Table 1).

[0075] Of course, the number of second portions of road forming the intersection with the first portion of road 101 is not limited to 2, this number extending for example to 3, 4, 5 or more second sections of road.

[0076] According to a particular embodiment, the following operations are implemented only when an absolute value of each angle value is less than a value of a limit angle, for example 10, 20, 25 or 30°.

[0077] This limit angle value corresponds for example to a parameter stored in memory, for example in the memory of the computer implementing the process, this parameter being for example modifiable via a human-machine interface (HMI) on board the vehicle 10.

[0078] Indeed, for low absolute angle values, the certainty of the second portion of road which is taken by the vehicle 10 is not maximum. The following operations thus make it possible, for example, to adapt a speed of the vehicle 10 on approach and in the intersection as a function of this uncertainty of direction to follow. These operations thus aim to control the speed of the vehicle 10 as a function of probabilities of a selection of a second portion of road and to improve the prediction of the second portion of road to be taken.

[0079] In a second operation, information representative of a threshold distance associated with the intersection is determined.

[0080] Such a threshold distance corresponds, for example, to a limit distance from which the choice of a second section of road is validated or final.

[0081] This distance is for example expressed in meters or hundreds of meters and is for example equal to 10, 20 or 50m. According to another example, this distance is determined as a function of the speed of the vehicle 10 and a time required by the vehicle 10 to travel the threshold distance at this speed. For example, the time is determined and equal to 3 or 5s and the speed is obtained for example from an odometer. The threshold distance is then determined using the following formula:

[0082] D = v / 1

[0083] With: - D the threshold distance expressed in meters (m), - v the current speed of the vehicle 10 expressed in meters per second (m / s), and -1 the duration determined in seconds (s).

[0084] In the case where a level of certainty is determined as to the choice of a second portion of road to be taken by the vehicle 10 from among the set of second portions of roads 102, 103, then the level of certainty is maximum once the vehicle 10 is located at a distance from the intersection less than this threshold distance.

[0085] A speed value is also determined for each second portion of road 102, 103 based on the intersection data.

[0086] Depending for example on the absolute value of the angle formed between a direction of a second portion of road and a direction of the first portion of road at At the intersection, a speed value is determined, linked to each second portion of road 102, 103.

[0087] For example, the smaller the absolute value of the angle, the higher the speed value. Or conversely, the larger the absolute value of the angle, the lower the speed associated with the second portion of road.

[0088] According to the example of table 1, a speed V1 is associated with the second portion of road 102 called the second continuation portion of road and a speed V2 is associated with the other second portion of road 103.

[0089] These speeds correspond to the ideal speed that the vehicle 10 must reach to take each of the second sections of road 102, 103.

[0090] The threshold distance is, for example, the distance required to change from speed V1 to V2, or vice versa, comfortably or safely before reaching the intersection.

[0091] In an additional operation, a first speed of the vehicle 10 corresponding to the speed value associated with the second portion of continuation road is checked.

[0092] The vehicle 10 then advances at an ideal speed to take the most probable path, in this example the second portion of continuation road 102 with the speed VL

[0093] In an operation, when the distance separating the vehicle 10 from the intersection is less than or equal to the threshold distance, for example, when the vehicle 10 reaches a position at a distance from the intersection equal to the threshold distance, directional data representative of a direction of a variation of a steering angle of the vehicle 10 are received.

[0094] According to an exemplary embodiment, the vehicle 10 thus advantageously incorporates a steering wheel angle sensor (called CAV sensor and also called steering angle transmitter) configured to measure the steering wheel angle values. Such a sensor is for example connected to the computer in charge of the process.

[0095] The variation of the angle of the steering wheel of the vehicle 10 is carried out with the aim of following a trajectory making it possible to take one of the second portions of road 102, 103. The value of the variation of the angle of the steering wheel of the vehicle 10 thus informs the computer about the orientation and the choice of a trajectory of the vehicle 10.

[0096] In one operation, a second road portion is selected, for example by the computer, from among the plurality of second road portions 102, 103 based on the intersection data and the directional data.

[0097] This second portion of road corresponds, with more certainty than previously, to the second portion of road taken by the vehicle 10. This is for example the second portion of continuation road 102 in the example of the table 1, but is, according to another example, another second portion of road 103 still following the example of table 1.

[0098] In a following operation, a second speed of the vehicle 10 corresponding to the speed value associated with the second selected road portion is checked.

[0099] Thus, following the example of table 1, if the second selected road portion is the second continuation road portion 102, then the speed of the vehicle 10 is equal to the speed VI previously defined. The vehicle then approaches and then passes the intersection at the second speed, here VI, taking the second continuation road portion at an ideal speed.

[0100] Still following the example of [Fig.l], if the second portion of road selected is the other second portion of road 103, then the speed of the vehicle 10 is equal to the speed V2 previously defined. The vehicle 10 then changes from the first speed, here VI, to the second speed, here V2, before arriving at the intersection which it changes to the second ideal speed to take the other second portion of road 103.

[0101] Thus, the driving assistance system responsible for controlling the speed of the vehicle 10 in an intersection allows the vehicle 10 to pass an intersection at an ideal speed.

[0102] For example, in a P-ACC system, the speed and / or acceleration of the vehicle 10 are automatically regulated when an intersection is detected, based on the distance between the vehicle 10 and the start of the second selected road portion indicated in Table 1 and / or based on the angle associated with the second selected road portion which is indicated in Table 1. For example, the speed of the vehicle 10 is automatically set as the vehicle 10 approaches the intersection with passage of the intersection at a speed adequate to take the second selected road portion.

[0103] [Fig. 2] schematically illustrates a device 2 configured to control the speed of a vehicle in an intersection, for example the vehicle 10, according to a particular and non-limiting exemplary embodiment of the present invention. The device 2 corresponds for example to a device on board the vehicle 10, for example a computer.

[0104] The device 2 is for example configured for the implementation of the operations described with regard to [Fig.l] and / or the steps of the method described with regard to [Fig.3]. Examples of such a device 2 include, but are not limited to, on-board electronic equipment such as an on-board computer of a vehicle, an electronic calculator such as an ECU (“Electronic Control Unit”), a smartphone, a tablet, a laptop. The elements of the device 2, individually or in combination, can be integrated in a single integrated circuit, in several integrated circuits, and / or in discrete components. The device 2 can be implemented in the form of electronic circuits or software (or computer) modules or even a combination of electronic circuits and software modules.

[0105] The device 2 comprises one (or more) processor(s) 20 configured to execute instructions for carrying out the steps of the method and / or for executing the instructions of the software(s) embedded in the device 2. The processor 20 may include integrated memory, an input / output interface, and various circuits known to those skilled in the art. The device 2 further comprises at least one memory 21 corresponding for example to a volatile and / or non-volatile memory and / or comprises a memory storage device which may comprise volatile and / or non-volatile memory, such as EEPROM, ROM, PROM, RAM, DRAM, SRAM, flash, magnetic or optical disk.

[0106] The computer code of the embedded software(s) comprising the instructions to be loaded and executed by the processor is for example stored in the memory 21.

[0107] According to various particular and non-limiting embodiments, the device 2 is coupled in communication with other similar devices or systems and / or with communication devices, for example a TCU (from the English “Telematic Control Unit” or in French “Telematic Control Unit”), for example via a communication bus or through dedicated input / output ports.

[0108] According to a particular and non-limiting exemplary embodiment, the device 2 comprises a block 22 of interface elements for communicating with external devices, for example a remote server or the “cloud”, other nodes of the ad hoc network. The interface elements of the block 22 comprise one or more of the following interfaces: - RF radio frequency interface, for example Wi-Fi® type (according to IEEE 802.11), for example in the 2.4 or 5 GHz frequency bands, or Bluetooth® type (according to IEEE 802.15.1), in the 2.4 GHz frequency band, or Sigfox type using UBN (Ultra Narrow Band) radio technology, or LoRa in the 868 MHz frequency band, LTE (Long-Term Evolution), LTE-Advanced; - USB interface (from the English “Universal Serial Bus” or “Universal Serial Bus” in French); - HDMI interface (from the English “High Definition Multimedia Interface” or “High Definition Multimedia Interface” in French); - LIN interface (from the English “Local Interconnect Network”).

[0109] Data is for example loaded to the device 2 via the interface of the block 22 using a Wi-Fi® network such as according to IEEE 802.11, an ITS G5 network based on IEEE 802.1 Ip or a mobile network such as a 4G (or 5G) network based on the LTE (Long Term Evolution) standard defined by the 3GPP consortium, in particular an LTE-V2X network.

[0110] According to another particular and non-limiting exemplary embodiment, the device 2 comprises a communication interface 23 which makes it possible to establish communication with other devices (such as other computers of the on-board system) via a communication channel 230. The communication interface 23 corresponds for example to a transmitter configured to transmit and receive information and / or data via the communication channel 230. The communication interface 23 corresponds for example to a wired network of the CAN (from the English “Controller Area Network” or in French “Réseau de contrôles”) type, CAN FD (from the English “Controller Area Network Flexible Data-Rate” or in French “Réseau de contrôles à débit de données flexible”), FlexRay (standardized by the ISO 17458 standard) or Ethernet (standardized by the ISO / IEC 802-3 standard).

[0111] According to a particular and non-limiting exemplary embodiment, the device 2 can provide output signals to one or more external devices, such as a display screen, touch-sensitive or not, one or more speakers and / or other peripherals (projection system) via respective output interfaces. According to a variant, one or other of the external devices is integrated into the device 2.

[0112] [Fig. 3] illustrates a flowchart of the different steps of a method for controlling the speed of a vehicle in an intersection, for example of the vehicle 10, according to a particular and non-limiting exemplary embodiment of the present invention. The method is for example implemented by a device on board the vehicle 10 or by the device 2 of [Fig. 2].

[0113] In a first step 31, intersection data representative of an intersection between the first portion of road 101 on which the vehicle 10 is traveling and a set of second portions of road 102, 103 located downstream of a current position of the vehicle 10 are received.

[0114] The intersection data comprises for each second road portion: - a distance value between the current position of the vehicle 10 and the intersection between the first road portion 101 and each second road portion 102, 103, and - an angle value between the first road portion 101 and each second road portion 102, 103, the same distance value being associated with a plurality of second road portions of the set and a second road portion, called a continuation, of the plurality of second road portions 102, 103 being identified in the data intersection as corresponding to a continuity of the first portion of road.

[0115] In a second step 32, information representative of a threshold distance associated with the intersection is determined. For each second portion of road, a speed value is also determined based on the intersection data.

[0116] In a third step 33, a first speed of the vehicle 10 corresponding to the speed value associated with the second portion of continuation road is checked.

[0117] In a fourth step 34, directional data representative of a direction of a variation of a steering angle of the vehicle 10 are received when a distance separating the vehicle 10 from the intersection is less than or equal to the threshold distance.

[0118] In a fifth step 35, a second road portion is selected from the plurality of second road portions 102, 103 based on the intersection data and the directional data.

[0119] In a sixth operation 36, a second speed of the vehicle 10 corresponding to the speed value associated with the second selected portion of road is controlled.

[0120] According to a variant, the variants and examples of the operations described in relation to [Fig.l] apply to the steps of the method of [Fig.3].

[0121] Of course, the present invention is not limited to the exemplary embodiments described above but extends to a method for controlling the speed of a vehicle in an intersection which would include secondary steps without thereby departing from the scope of the present invention. The same would apply to a device configured for implementing such a method.

[0122] The present invention also relates to a vehicle, for example an automobile or more generally an autonomous land-based motor vehicle, comprising the device 2 of [Fig.2].

Claims

Claims

1. A method of controlling a speed of a vehicle (10), said vehicle (10) traveling on a first portion of road (101) of a road environment (1), said method comprising the following steps: - reception (31) of intersection data representative of an intersection between said first road portion (101) and a set of second road portions (102, 103) located downstream of a current position of said vehicle (10), said intersection data comprising for each second road portion: • a distance value between said current position of said vehicle (10) and the intersection between said first portion of road (101) and said each second portion of road (102, 103), and • an angle value between said first portion of road (101) and said each second portion of road (102, 103), the same distance value being associated with a plurality of second road portions of said set, a second road portion, called a continuation portion, of said plurality of second road portions (102, 103) being identified in said intersection data as corresponding to a continuity of said first road portion; - determination (32) of information representative of a threshold distance associated with said intersection and, for each second portion of road, of a speed value, as a function of said intersection data; - control (33) of a first speed of said vehicle corresponding to the speed value associated with said second portion of continuation road; - reception (34) of directional data representative of a direction of a variation of a steering angle of said vehicle (10) when a distance separating the vehicle (10) from said intersection is less than or equal to said threshold distance; - selection (35) of a second road portion from among said plurality of second road portions (102, 103) as a function of said intersection data and said directional data; and - control (36) of a second speed of said vehicle corresponding to the speed value associated with the second selected portion of road.

2. Method according to claim 1, for which the steps of determining (32) said information representative of a threshold distance and said speed values, control (33) of said first speed, reception (34) of said directional data and control (34) of said second speed are implemented only when an absolute value of said each angle value is less than a value of a limit angle.

3. A method according to claim 2, wherein said limit angle value is equal to 25°.

4. A method according to one of claims 2 to 3, wherein, when said plurality of second road portions (102, 103) comprises two second road portions, an intersection between the first road portion (101) and said two second road portions (102, 103) corresponds to a Y-shaped intersection.

5. Method according to one of claims 1 to 4, for which said controls (33, 36) are implemented by a predictive adaptive cruise control system, called P-ACC system.

6. Method according to one of claims 1 to 5, for which said intersection data is cartographic data.

7. Computer program comprising instructions for implementing the method according to any one of the preceding claims, when these instructions are executed by a processor.

8. A computer-readable recording medium on which is recorded a computer program comprising instructions for carrying out the steps of the method according to one of claims 1 to 6.

9. Device (2) for controlling a speed of a vehicle, said device (2) comprising a memory (21) associated with at least one processor (20) configured for implementing the steps of the method according to any one of claims 1 to 6.

10. Vehicle (10) comprising the device (2) according to claim 9.

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