Method and device for controlling an on-board driver assistance system in a vehicle

Abstract

The present invention relates to a method and device for controlling an ADAS system of a first vehicle (10). To this end, the environment (1) of the first vehicle (10) is spatially subdivided into 9 zones (11 to 19) forming a 3 x 3 matrix centered on a central zone (15) comprising the first vehicle (10). A presence indicator for a second vehicle (101, 102, 103, 104) as a function of time is determined for each zone (11 to 19). A first and a second vehicle density indicator are determined for a first and a second part of the matrix, respectively, as a function of the presence indicators of the zones included in the first and second parts, respectively. The ADAS system is controlled based on the first density indicator and / or the second density indicator. (See Figure 1 for abbreviations.)

Description

Title of the invention: Method and device for controlling a driving assistance system on board a vehicle Technical field

[0001] The present invention relates to methods and devices for controlling a driving assistance system, known as an AD AS system, of a vehicle. The present invention also relates to a method and a device for determining one or more control parameters of a vehicle. The present invention also relates to a method and a device for controlling a vehicle, in particular an autonomous vehicle. Technological background

[0002] Some contemporary vehicles are equipped with functions or system(s) or driving assistance, known as AD AS (from the English “Advanced Driver-Assistance System” or in French “Advanced Driving Assistance System”).

[0003] Among these systems, the adaptive cruise control system, known as ACC (from the English "Adaptive Cruise Control"), has as its primary function the automatic regulation, in an adaptive manner, of the speed of the vehicles equipped therewith according to their environment. Such an ACC system determines one or more acceleration instructions according to a speed instruction and information relating to the environment of the vehicle, the acceleration instruction(s) being capable of regulating the speed of the vehicle in an adaptive manner, that is to say by taking into account the environment of the vehicle.

[0004] Among these systems, the semi-automatic lane change system, called the SALC system (from the English "Semi-Automatic Lane Change") has the primary function of assisting the driver of a vehicle when the driver wishes to change lanes. Upon detecting the activation of the turn signals on one side of the vehicle to indicate its intention to change lanes from a current lane to a target lane on the side where the turn signals have been activated by the driver, the SALC system operates the lane change after having carried out some checks.

[0005] Each of these systems uses vehicle environment data, obtained for example from sensors embedded in the vehicle, such as radars for example. Concerning the ACC system, this environment information corresponds for example to the distance between the vehicle equipped with the ACC system and a vehicle traveling in front, to the speed (for example relative) of the vehicle traveling in front, to the acceleration (or deceleration) of the vehicle traveling in front and / or to a regulatory speed limit. Such a vehicle traveling in front is called a target vehicle or target object of the ACC system. The acceleration setpoint(s) are, for example, determined from a control law based on estimates of the torque supplied by a powertrain (for example, a thermal or electric motor) to one or more wheels of the vehicle and the current acceleration of the vehicle.

[0006] This environmental information is particularly important for a vehicle, for example to improve the safety of the vehicle by taking into account the environment surrounding it, in particular other vehicles.

[0007] The environmental data used for these systems are however incomplete and only target a portion of the vehicles located in the vehicle's environment. For example, the ACC system essentially uses data relating to the presence of a vehicle traveling in front of the vehicle carrying the ACC system. The SALC system, for its part, essentially uses data relating to the presence of a vehicle in the destination traffic lane. Summary of the invention

[0008] An object of the present invention is to solve at least one of the problems of the technological background described above.

[0009] Another object of the present invention is to improve knowledge of the vehicle's environment for improved operation of the on-board AD AS system(s).

[0010] According to a first aspect, the present invention relates to a method for controlling a driving assistance system, called AD AS system, on board a first vehicle, the method comprising the following steps:

[0011] - receiving data representative of an environment surrounding the first vehicle from at least one object detection sensor on board the first vehicle;

[0012] - spatial subdivision of the environment into a plurality of zones, the plurality of zones forming a 3-row, 3-column matrix centered on a central zone comprising the first vehicle, the matrix comprising a central column surrounded on the left by a left column and on the right by a right column;

[0013] - for each zone of the plurality of zones, determination of an indicator of presence representative of presence or absence of a second vehicle as a function of time in each zone according to the data;

[0014] - determination of a first vehicle density indicator associated with a first part of the matrix based on the presence indicators of the areas included in the first part of the matrix and a second vehicle density indicator associated with a second part of the matrix based on the presence indicators of the areas included in the second part, the first part comprising the central column and the left column of the matrix and the second part comprising the central column and the right column of the matrix;

[0015] - control of the AD AS system according to a third density indicator of vehicles, the third vehicle density indicator being a function of the first vehicle density indicator and / or the second vehicle density indicator.

[0016] The use of a density indicator representative of the density of vehicles in the environment of the first vehicle makes it possible to adapt the control of the AD AS systems (for example the setpoint acceleration values) of the first vehicle as a function of the density of vehicles in the immediate environment of the first vehicle, in addition to the parameters conventionally used for the control of such an AD AS system. For example, when the density of vehicles circulating around the first vehicle is high, the setpoint acceleration calculated by the ACC system can be adapted, for example reduced, compared to a raw or potential acceleration determined simply from the dynamic parameters of the first vehicle and the dynamic parameters of a target vehicle circulating in front of the first vehicle.This improves the comfort of the driver and passengers of the first vehicle by adapting the dynamics of the first vehicle to the traffic conditions around the first vehicle.

[0017] According to a variant, for each zone, the presence indicator at a current time is equal to the presence indicator at a time preceding the current time to which is added a first determined positive value when a second vehicle is detected in the zone at the current time and to which is added a second determined negative value when a second vehicle detected in the zone at the previous time is no longer detected in the zone at the current time.

[0018] According to another variant, the second determined value corresponds to the opposite of the first determined value or the absolute value of the first determined value is different from the absolute value of the second determined value.

[0019] According to another variant, the first density indicator corresponds to an average of the presence indicators of the zones included in the first part of the matrix and the second density indicator corresponds to an average of the presence indicators of the zones included in the second part of the matrix.

[0020] According to an additional variant, each zone of the plurality of zones has a rectangular shape defined by a longitudinal dimension along a longitudinal axis corresponding to a direction of movement of the first vehicle and by a lateral dimension along a lateral axis orthogonal to the longitudinal axis,

[0021] the longitudinal dimension of the zones of the central line of the matrix comprising the central zone corresponding to a sum of a first determined distance and a second determined distance, the first determined distance corresponding to a distance between a reference point of the first vehicle and a first boundary between the center line and a first row of the matrix located in front of the first vehicle, the second determined distance corresponding to a distance between the reference point of the first vehicle and a second boundary between the center line and a third row of the matrix located behind the first vehicle,

[0022] the longitudinal dimension of the zones of the first line being a function of a first temporal duration, and

[0023] the longitudinal dimension of the zones of the third line being a function of a second temporal duration.

[0024] According to another variant, the third indicator corresponds:

[0025] - to an average of the first density indicator and the second density indicator density when no indicator of the first vehicle is activated;

[0026] - at the first density indicator only when a left indicator of the first vehicle is activated; and

[0027] - at the second density indicator only when a right indicator of the first vehicle is activated.

[0028] According to an additional variant, the AD AS system corresponds to an adaptive speed regulation system, called ACC system, the method further comprising a determination of an acceleration setpoint for the first vehicle by applying a determined coefficient to a potential acceleration determined by the ACC system, the coefficient being between 0 and 1 and a function of the third vehicle density indicator following a decreasing monotonic function of the third indicator.

[0029] According to a second aspect, the present invention relates to a device for controlling a driving assistance system, called AD AS system, of a vehicle, 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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

[0037] 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 5, in which:

[0038] [Fig-1] schematically illustrates an environment of a first vehicle, according to a particular embodiment of the present invention;

[0039] [Fig.2] illustrates a function representing the evolution of a coefficient as a function of a density indicator determined for the first vehicle of [Fig.l], according to a particular exemplary embodiment of the present invention;

[0040] [Fig.3] illustrates a diagram representing two acceleration curves as a function of the density indicator for the first vehicle of [Fig.l], according to a particular exemplary embodiment of the present invention;

[0041] [Fig.4] schematically illustrates a device configured to control an AD AS system of the first vehicle of [Fig. 1], according to a particular exemplary embodiment of the present invention.

[0042] [Fig.5] illustrates a flowchart of the different steps of a method for controlling an on-board AD AS system without the first vehicle of [Fig.l], according to a particular exemplary embodiment of the present invention. Description of examples of implementation

[0043] A method and a device for controlling one or more AD AS systems embedded in a vehicle will now be described in the following with joint reference to Figures 1 to 5. The same elements are identified with the same reference signs throughout the description which follows.

[0044] According to a particular and non-limiting example of embodiment of the present invention, the control of an AD AS system (for example an ACC system and / or a SALC system) of a first vehicle comprises the reception, for example by a computer of the on-board system of the first vehicle, of a set of data representative of the environment around the first vehicle. These data are for example received from a computer in charge of controlling object detection sensors (for example radars) equipping the first vehicle. The environment around the first vehicle, or at least part of this environment, is subdivided into a plurality of zones, for example 9 zones, centered on a central zone in which the first vehicle is located.The plurality of zones thus forms a 3x3 matrix with 3 columns and 3 rows, the central column comprising the central zone, this central column being surrounded by a left column (to the left of the central column according to the direction of travel of the first vehicle) and a right column (to the right of the central column according to the direction of travel of the first vehicle). A presence indicator representative of the presence or absence of a second vehicle in each zone as a function of time is determined based on the data received.From the presence indicators associated with the areas of the matrix, a first vehicle density indicator associated with a first part of the matrix is ​​determined as a function of the presence indicators of the areas included in the first part of the matrix and a second vehicle density indicator associated with a second part of the matrix is ​​determined as a function of the presence indicators of the areas included in the second part. The first part of the matrix advantageously comprises the central column and the left column of the matrix and the second part of the matrix advantageously comprises the central column and the right column of the matrix. A third vehicle density indicator is determined as a function of the first indicator and / or the third indicator, the AD AS system being controlled as a function of this third indicator.

[0045] The use of a density indicator representative of the density of vehicles in the environment of the first vehicle makes it possible to adapt the control of the AD AS systems (for example the setpoint acceleration values) of the first vehicle as a function of the density of vehicles in the immediate environment of the first vehicle, in addition to the parameters conventionally used for the control of such an AD AS system. For example, when the density of vehicles circulating around the first vehicle is high, the setpoint acceleration calculated by the ACC system can be adapted, for example reduced, compared to a raw or potential acceleration determined simply from the dynamic parameters of the first vehicle and the dynamic parameters of a target vehicle traveling in front of the first vehicle. This makes it possible to improve the comfort of the driver and passengers of the first vehicle by adapting the dynamics of the first vehicle to the traffic conditions around the first vehicle.

[0046] [Fig. 1] schematically illustrates an environment 1 of a first vehicle 10, according to a particular and non-limiting exemplary embodiment of the present invention.

[0047] [Fig.l] illustrates a first vehicle 10, for example a motor vehicle, carrying one or more sensors configured to detect the presence of objects in the environment 1 of the first vehicle 10. According to other examples, the first vehicle 10 corresponds 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.

[0048] The first vehicle 10 corresponds to a vehicle traveling under the total supervision of a driver or traveling in an autonomous or semi-autonomous mode. The first vehicle travels according to a level of autonomy equal to 0 or according to a level of autonomy ranging from 1 to 5 for example, 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 having 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.

[0049] The first vehicle 10 travels for example on a portion of road with several traffic lanes, for example with two or three traffic lanes, the two or three traffic lanes being for example in the same direction of travel.

[0050] According to the example of [Fig.l], a set of second vehicles 101, 102, 103, 104 circulate in the environment 1 around the first vehicle 10, with for example the second vehicle 101 circulating in front of the first vehicle 10, for example in the same traffic lane as that of the first vehicle 10, at a determined distance which can vary over time (depending on the dynamic behavior of the first vehicle 10 and the second vehicle 101), a second vehicle 102 circulating on the right behind the first vehicle 10 and two second vehicles 103, 104 circulating on the left behind the first vehicle 10.

[0051] The first vehicle 10 for example carries one or more of the following sensors:

[0052] - one or more millimeter wave radars arranged on the first vehicle 10, for example at the front, at the rear, on each front / rear corner of the vehicle; each radar is adapted to emit electromagnetic waves and to receive the echoes of these waves returned by one or more objects (for example the second vehicle 101 located in front of the first vehicle 10 according to the example of [Fig.l]), with the aim of detecting obstacles and their distances from the first vehicle 10; and / or

[0053] - one or more LIDAR(s) (from the English “Light Detection And Ranging”, or “ Detection and estimation of distance by light” in French), a LIDAR sensor corresponding to an optoelectronic system composed of a laser emitting device, a receiving device comprising a light collector (to collect the part of the light radiation emitted by the emitter and reflected by any object located in the path of the light rays emitted by the emitter) and a photodetector which transforms the collected light into an electrical signal; a LIDAR sensor thus makes it possible to detect the presence of objects (for example the second vehicle 101) located in the emitted light beam and to measure the distance between the sensor and each detected object; and / or

[0054] - one or more cameras (associated or not with a depth sensor) for the acquisition of one or more images of the environment around the first vehicle 10 located in the field of vision of the camera(s).

[0055] The data obtained from this or these sensors vary according to the type of sensor. When it is a radar or a LIDAR, the data correspond for example to distance data between points of the detected object and the sensor. Each detected object is thus represented by a point cloud (each point corresponding to a point of the object receiving the radiation emitted by the sensor and reflecting at least part of this radiation), the point cloud representing the envelope (or part of the envelope) of the detected object as seen by the sensor and ultimately by the vehicle 10 carrying the sensor. When it is a video camera, the data correspond to data associated with each pixel of the acquired image(s), for example gray level values ​​coded on for example 8, 10, 12 or more bits for each color channel, for example RGB (from the English “Red, Green, Blue” or in French “Rouge, vert, bleu”).These data make it possible, for example, to determine the successive positions taken by an object moving in the environment 1, for example the second vehicle 101, and to deduce therefrom one or more dynamic parameters of the moving object such as the speed and / or the acceleration. These data also make it possible to determine the lines on the ground in order, for example, to participate in determining whether the second vehicle 101 and the first vehicle 10 belong to the same traffic lane, for example.

[0056] The data acquired by the on-board sensor(s) feed, for example, one or more driving assistance systems, known as AD AS (from the English “Advanced Driver-Assistance System” or in French “Système d’aide à la conduite avance”) on board the first vehicle 10. Such an AD AS system is configured to assist, or even replace, the driver of the first vehicle 10 to control the first vehicle 10 on its route.

[0057] The first vehicle 10 for example carries an AD AS system corresponding to an automatic speed regulation system, called an ACC system. When the ACC system is activated, the ACC system aims to achieve a set acceleration, denoted A(t) (also called raw set acceleration or potential acceleration), which varies over time 't' and which makes it possible to maintain a determined safety distance from the second vehicle 101 (which corresponds for example to the target object (also called target vehicle) of the ACC system) upstream of the first vehicle 10, that is to say a target vehicle traveling in front of the first vehicle 10 in the same direction of travel on the same traffic lane as long as this second vehicle 101 is detected by the sensors on board the first vehicle 10.

[0058] As long as the second vehicle 101 is selected as the target vehicle of the ACC system, an acceleration value (called the raw or potential setpoint) is for example determined at a current time 't' by the ACC system from a set of data obtained from one or more object detection sensors on board the first vehicle 10 and / or from dynamic parameters of the first vehicle 10. The target acceleration value (expressed in ms 2) is for example calculated from:

[0059] - data representative of the dynamic behavior of the second vehicle 101 (for example speed and / or acceleration), these data being for example obtained from a set of positions taken by the second vehicle 101 over a time interval preceding the current instant 't' for which the target acceleration is determined. The data on the positions taken by the second vehicle 101 are advantageously determined from the data received from the object detection sensor(s) on board the first vehicle 10;

[0060] - data representative of the dynamic behavior of the first vehicle 10 (for example speed, acceleration, distance from the second vehicle 101), these data being obtained from sensors on board the first vehicle 10, the distance being for example obtained from the data received from the object detection sensor(s); and / or

[0061] - setpoint parameters provided to the ACC system, such as for example a distance or a target inter-vehicle time (IVT or IVT), these parameters being recorded in memory or entered by a user via a Human-Machine Interface, known as HMI.

[0062] According to another example, the first vehicle 10 incorporates a semi-automatic lane change system, called a SALC system (from the English “Semi-Automatic Lane Change”), for example in addition to the ACC system. Such a system is based in particular on the detection and recognition of the marking lines on the ground. to authorize or not the lane change from a current traffic lane to a traffic lane adjacent to this current traffic lane, and when the change is authorized, to control the maneuver allowing the first vehicle 10 to change lane. Among the checks carried out by the SALC system to authorize or not the lane change, the SALC system verifies that the road marking line delimiting the current traffic lane from the target adjacent lane corresponds to a broken line for which the lane change is authorized.

[0063] A process for controlling a driving assistance system, called AD AS system, of a vehicle, for example the first vehicle 10 incorporating the ACC system and / or the SALC system, is advantageously implemented by the first vehicle 10, that is to say by a computer or a combination of computers of the on-board system of the first vehicle 10, for example by the computer(s) responsible for controlling the ACC system and / or the SALC system.

[0064] In a first operation, data representative of the environment 1, and in particular objects such as second vehicles 101 to 104, are received.

[0065] These data are for example received from one or more sensors, for example radars and / or Lidars of the first vehicle 10, via one or more communication buses of the on-board system of the first vehicle 10, for example a communication bus of the CAN (Controller Area Network) type, CAN FD (Controller Area Network Flexible Data-Rate), FlexRay (according to the ISO 17458 standard), Ethernet (according to the ISO / IEC 802-3 standard) or LIN (Local Interconnect Network) type.

[0066] These data correspond for example to data representative of distances of each of the detected objects (in particular the second vehicles) with respect to the first vehicle 10, for example distances between a point of the first vehicle 10 and a set of points forming an outer envelope of each second vehicle 101 to 104 as seen from the first vehicle 10.

[0067] In a second operation, the environment 1 is subdivided or virtually cut into a plurality of zones 11 to 19, each zone of the plurality corresponding for example to a two-dimensional surface forming a rectangle along a first dimension, called longitudinal, along the longitudinal axis Y corresponding to the axis along which the first vehicle 10 moves and along a second dimension, called lateral, along the lateral axis X orthogonal to the longitudinal axis Y.

[0068] All of the zones 11 to 19 advantageously form a matrix with 3 rows and 3 columns centered on a central zone (or cell) 15 comprising (or in which finds) the first vehicle 10 at a current time, the matrix comprising a central column (comprising the zones or cells 12, 15, 18) surrounded on the left by a left column (comprising the zones or cells 11, 14, 17) and on the right by a right column (comprising the zones or cells 13, 16, 19).

[0069] The matrix also comprises a central line (comprising the zones or cells 14, 15, 16) surrounded by a first line (in front of the first vehicle 10 in the direction of movement of the first vehicle 10) comprising the zones or cells 11, 12, 13 and a third line (behind the first vehicle 10) comprising the zones or cells 17, 18, 19.

[0070] The zones or cells of the matrix evolve as the first vehicle 10 moves in such a way that the matrix is ​​centered on the central zone 15 comprising the first vehicle 10.

[0071] The width L1, L2 and L3 (along the X axis, called the lateral dimension of the column or of the zones which compose it) of each of the columns takes a determined value, for example equal to 3, 3.5 or 4 m. The widths of each of these columns are for example identical. According to a variant, the width L1 of the left column and / or the width L3 of the right column is / are less than the width L2 of the central column. For example, the width L1 and / or L3 is equal to 1.5, 2 or 2.5 m.

[0072] The length (along the Y axis, called the longitudinal dimension of the line or of the zones that compose it) of the central line comprising the zones 14, 15, 16 corresponds for example to the sum of DI and D2. DI corresponds to the distance (along the Y axis) between a reference point of the first vehicle 10 (for example the middle of the rear axle or the barycenter of the first vehicle 10) and the limit between the first line and the central line. This distance DI is for example equal to 5, 6, 7 or 10 m. D2 corresponds to the distance (along the Y axis) between the reference point of the first vehicle 10 and the limit between the third line and the central line. This distance D2 is for example equal to 2, 3 or 4 m.

[0073] The length of the first line is advantageously defined by a first time duration Tl (or a first value of a time horizon), for example equal to 2 or 3 s. Thus, the length of this first line in meters is obtained by multiplying the current speed of the first vehicle 10 by this first time duration TL.

[0074] In the same way, the length of the third line is advantageously defined by a second time duration T2 (or a second value of a time horizon), for example equal to 2 or 3 s. Thus, the length of this third line in meters is obtained by multiplying the current speed of the first vehicle 10 by this second time duration T2.

[0075] The values ​​of the dimensions L1, L2, L3, D1, D2, T1, T2 are for example fixed by the manufacturer of the first vehicle 10 or by the designer of the AD AS system(s). on-board, these values ​​being stored in an on-board memory in the first vehicle 10. According to a variant, one or more of these values ​​can be configured, for example by the driver via an HMI (Human-Machine Interface).

[0076] In a third operation, for each zone 11 to 19 of the matrix, a presence indicator representative of the presence or absence of a second vehicle is determined as a function of the data received in the first operation. This presence indicator is advantageously a function of time and corresponds for example to a value between 0 and 1 evolving as a function of time and as a function of the detection of the presence (or absence of detection) of a second vehicle in the zone considered, the detection being for example implemented at regular intervals (for example every 100, 200, 500 ms) to update the presence indicator of each zone.

[0077] The presence indicator Ip in a zone considered is for example determined from the following equation:

[0078] Ip(t) = Ip(t-dt) + A(t)

[0079] With Ip(t) the presence indicator at time t, Ip(t-dt) the presence indicator determined at the previous time, with a time difference between the current time t and the previous time equal to dt (for example equal to 100, 200 or 500 ms), and A(t) equal to an increment or decrement value taking a first determined value (increment) as a function of the detection of the presence of a second vehicle in the zone considered at the current time t and a second determined value when the presence of no second vehicle is detected in the zone considered while a second vehicle was present in the zone considered at the previous time.

[0080] The first value (increment), noted Al(t), is a positive value (A 1 (t) > 0) less than 1. Al(t) is for example equal to 0.1, 0.15, 0.2 or 0.3. At each detection of a second vehicle in the zone considered, A1 (t) takes the value which is associated with it, whatever the detection state of a second vehicle in the zone considered at the previous instant.

[0081] The second value (decrement), noted A2(t), is a negative value (A2(t) < 0) greater than -1. A2(t) is for example equal to -0.1, -0.15, -0.2 or -0.3. When a second vehicle was present in the zone considered at the previous instant and this second vehicle is no longer detected as present in this zone considered at the current instant, then A2(t) takes the value associated with it.

[0082] According to a particular example, the second value corresponds to the value opposite to the first value, that is to say that:

[0083] A2(t) = - Al(t), and

[0084] [Math.l] | A l(t)| = | A 2(t) |

[0085] According to another example, the absolute value of the first value is different from the absolute value of the second value, i.e.:

[0086] [Math.2] | A l(t)| * j A 2(t)|

[0087] For example, Al(t) = 0.1 and A2(t) = -0.2.

[0088] The values ​​of Al(t) and A2(t) are for example recorded in memory, for each zone, for a set of consecutive time instants at which they were determined or calculated. This makes it possible in particular to know or determine the detection state (present or absent) of a second vehicle in the zone considered at the instant preceding a current instant.

[0089] In a fourth operation, a first vehicle density indicator associated with a first part of the matrix is ​​determined based on the presence indicators of the areas included in the first part of the matrix. In the same way, a second vehicle density indicator associated with a second part of the matrix (different from the first part) is also determined based on the presence indicators of the areas included in the second part.

[0090] The first part comprises for example the central column and the left column, and the zones 11, 12, 14, 15, 17, 18 included in these 2 columns. The first indicator thus represents the density of vehicles to the left of the first vehicle 10, this left part including the central column to which the first vehicle 10 belongs.

[0091] The second part comprises for example the central column and the right column, and the zones 12, 13, 15, 16, 18, 19 included in these 2 columns. The second indicator thus represents the density of vehicles to the right of the first vehicle 10, this right part including the central column to which the first vehicle 10 belongs.

[0092] The first density indicator, noted Idl, corresponds for example to the average, at the current time of determination of this first density indicator, of the presence indicators of the zones included in the first part. Idl is thus obtained via the following equation:

[0093] [Math.3] ip^O lpi2(t> Ipl4(t> Ip^tH lp|7(t> lpJS(0 Idl= g

[0094] With Ipn(t) the presence indicator associated with zone 11, Ipi2(t) the presence indicator associated with zone 12, Ipi4(t) the presence indicator associated with zone 14, Ipi5(t) the presence indicator associated with zone 15, Ipn(t) the presence indicator associated with zone 17 and Ipi8(t) the presence indicator associated with zone 18.

[0095] The second density indicator, noted Id2, corresponds for example to the average, at the current time of determination of this second density indicator, of the presence indicators of the zones included in the second part. Id2 is thus obtained via the following equation:

[0096] [Math.4] Ip|2(t)+ Ip13(tH Ip|5(t> IpJ6(t)+ IP, ldi = g

[0097] With Ipn(t) the presence indicator associated with zone 13, Ipi6(t) the presence indicator associated with zone 16 and Ipi9(t) the presence indicator associated with zone 19.

[0098] Each column of zones is for example associated with a traffic lane, the central column representing the current traffic lane of the first vehicle 10.

[0099] According to another example, the 3 columns represent only 2 traffic lanes, the width and / or the location of the columns not corresponding exactly to the width and / or the location of the traffic lanes of the road on which the first vehicle 10 is traveling.

[0100] According to this example, the first indicator and the second indicator thus provide an indication of the density of vehicles present in an area located more to the left of the first vehicle 10 and in an area located more to the right of the first vehicle 10.

[0101] In a fifth operation, a third density indicator is determined as a function of the first density indicator and / or the second density indicator. The AD AS system(s) embedded in the first vehicle 10 are controlled as a function of this third density indicator, i.e. the third density indicator is taken into account by this or these AD AS systems to determine or calculate the parameters used to control the first vehicle 10 for the function(s) supported by this or these AD AS systems.

[0102] The third density indicator corresponds for example:

[0103] - to an average of the first density indicator and the second density indicator density when no indicator of the first vehicle is activated, i.e. Id = 0.5 * (Idl + Id2), with Id the third density indicator, Idl the first density indicator and Id2 the second density indicator;

[0104] - at the first density indicator only when a left indicator of the first vehicle is activated, i.e. Id = Idl; and

[0105] - at the second density indicator only when a right indicator of the first vehicle is activated, i.e. Id = Id2.

[0106] The processor in charge of the process receives, for example, information representative of the triggering of the indicators, when the indicators are activated on one side or the other of the first vehicle 10, for example by the driver of the first vehicle. This information is, for example, received from the computer in charge of the control of the turn signals of the first vehicle 10 in the form of a set of data, for example multiplexed. These calculators belong to a set of calculators and sensors forming the on-board system of the first vehicle 10. The calculators and / or sensors of the on-board system are connected in communication via one or more communication buses, for example one or more communication buses of the CAN (Controller Area Network) type, CAN FD (Controller Area Network Flexible Data-Rate), FlexRay (according to the ISO 17458 standard), Ethernet (according to the ISO / IEC 802-3 standard) or LIN (Local Interconnect Network) type.

[0107] According to a first example, the AD AS system corresponds to a SALC system. When the activation of the turn signals is detected on one side or the other, the SALC system uses the density indicator Id1 or Id2 depending on the side of the turn signal triggering as an additional control to decide whether the lane change from the current lane to the destination lane (on the side of the activated turn signals) can be made or must be delayed. Indeed, even if the free space is sufficient to allow a lane change, a high density of vehicles in the part on the side of the lane change can intimidate the driver and make him feel uncomfortable.The SALC system can therefore in this case delay the lane change depending on the density indicator or require confirmation from the driver, for example by triggering the rendering (for example the display) of a message to the driver via a dedicated HMI, requiring the driver to confirm their desire to implement the lane change or, on the contrary, to interrupt the lane change.

[0108] According to a second example, the AD AS system corresponds to an ACC system. According to this second example, the acceleration determined by the ACC system as a function of the dynamic parameters of the first vehicle 10 and of a target vehicle traveling in front of the first vehicle 10, called raw potential acceleration (denoted Apotentieue), is filtered by applying a coefficient (between 0 and 1) to this raw potential acceleration to obtain a set acceleration for the first vehicle 10.

[0109] This coefficient (noted k) is advantageously a function of the third density indicator (noted Id) determined in the fifth operation.

[0110] Thus, the set acceleration A is obtained from the following equation: [YES] A = k(Id) ApOtential

[0112] [Fig.2] illustrates a particular and non-limiting example of a function 21 between the coefficient (denoted k on the ordinate of diagram 2) and the third density indicator (denoted Id on the abscissa of diagram 2).

[0113] According to the example of [Fig.2], function 21 corresponds to a decreasing monotonic function of the coefficient k as a function of the third density indicator Id.

[0114] According to this example, k takes a maximum value for an interval of values ​​of Id between 0 and a first threshold value (for example equal to 0.2 or 0.3), the maximum value of k being for example equal to 0.9 or 1. The coefficient k takes a minimum value when the third density indicator reaches a second threshold value, for example equal to 0.7, 0.8 or 0.9, the minimum value of k being for example equal to 0.2, 0.3 or 0.4. The coefficient k decreases strictly according to a determined profile between the first threshold value and the second threshold value of the third density indicator Id.

[0115] The coefficient k thus makes it possible to reduce the raw potential acceleration calculated by the ACC system as a function of the third density indicator, the raw potential acceleration being all the more reduced or filtered as the third density indicator Id is high, at least up to a limit corresponding to the threshold value.

[0116] [Fig. 3] illustrates a diagram 3 representing two acceleration profiles (denoted A on the ordinate of diagram 3) obtained at the output of the ACC system of the first vehicle 10 as a function of the third density indicator (denoted id on the abscissa of diagram 3), according to a particular and non-limiting exemplary embodiment of the present invention.

[0117] According to the example of [Fig.3], the first acceleration profile 31 corresponds to the profile of the raw potential acceleration, that is to say to an acceleration determined by the ACC system without application of the coefficient k described with regard to [Fig.2], that is to say without filtering.

[0118] The second acceleration profile corresponds to the acceleration profile obtained by applying the coefficient k to the raw potential application calculated by the ACC system.

[0119] As shown in [Fig. 3], the profiles 31 and 32 are identical for low values ​​of the third density indicator, for example for Id values ​​lower than the first threshold value (for example lower than 0.1 or 0.2) and for high values ​​of the third density indicator, for example for Id values ​​higher than the third threshold value (for example higher than 0.7, 0.8 or 0.9). Over the range of Id values ​​between the first threshold value and the second threshold value, the value of the acceleration according to the second profile 32 is lower than the value of the acceleration according to the first profile 31, the acceleration according to the second profile 32 being filtered with respect to the acceleration according to the first profile 31 by applying the coefficient k (which varies as a function of Id) to the acceleration according to the first profile 31.

[0120] Such an example of implementation makes it possible to avoid excessive acceleration of the first vehicle (when the ACC system is active) when the density of vehicles is important. A high gross potential acceleration is for example determined by the ACC system when the target vehicle in front of the first vehicle 10 changes trajectory, for example changes lane. This target vehicle is then deselected by the ACC system to no longer correspond to the target object of the ACC system and the ACC system selects a new vehicle traveling in front of the first vehicle 10 as being the new target object. If this new target object is at a distance from the first vehicle 10 greater than the set DIV (inter-vehicle distance) or TIV (inter-vehicle time), then the gross potential acceleration calculated by the ACC system is high.

[0121] High acceleration can surprise or frighten the driver when the traffic around the first vehicle is dense. Filtering the raw potential acceleration by applying a coefficient depending on the third density indicator makes it possible to attenuate the acceleration when the density is high, which reassures the driver who feels safer.

[0122] [Fig. 4] schematically illustrates a device 4 configured to control one or more AD AS systems of a vehicle, for example of the first vehicle 10, according to a particular and non-limiting exemplary embodiment of the present invention. The device 4 corresponds for example to a device on board the first vehicle 10, for example a computer.

[0123] The device 4 is for example configured for the implementation of the operations described with regard to figures 1 to 3 and / or the steps of the method described with regard to [Fig.5]. Examples of such a device 4 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 4, individually or in combination, can be integrated in a single integrated circuit, in several integrated circuits, and / or in discrete components. The device 4 can be produced in the form of electronic circuits or software (or computer) modules or even a combination of electronic circuits and software modules.

[0124] The device 4 comprises one (or more) processor(s) 40 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 4. The processor 40 may include integrated memory, an input / output interface, and various circuits known to those skilled in the art. The device 4 further comprises at least one memory 41 corresponding for example to a volatile and / or non-volatile memory and / or comprises a memory storage device which may comprise memory volatile and / or non-volatile, such as EEPROM, ROM, PROM, RAM, DRAM, SRAM, flash, magnetic or optical disk.

[0125] 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 41.

[0126] According to various particular and non-limiting embodiments, the device 4 is coupled in communication with other similar devices or systems (for example other computers) 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.

[0127] According to a particular and non-limiting exemplary embodiment, the device 4 comprises a block 42 of interface elements for communicating with external devices. The interface elements of the block 42 comprise one or more of the following interfaces:

[0128] - RF radio frequency interface, for example of the Wi-Fi® type (according to IEEE 802.11), by 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 radio technology (Ultra Narrow Band), or LoRa in the 868 MHz frequency band, LTE (Long-Term Evolution), LTE-Advanced;

[0129] - USB interface (from the English "Universal Serial Bus" or "Universal Serial Bus" in French);

[0130] - HDMI interface (from the English “High Definition Multimedia Interface”, or “ High Definition Multimedia Interface” in French);

[0131] - LIN interface (from the English “Local Interconnect Network”, or in French “Réseau local interconnected”).

[0132] According to another particular and non-limiting exemplary embodiment, the device 4 comprises a communication interface 43 which makes it possible to establish communication with other devices (such as other computers of the on-board system) via a communication channel 430. The communication interface 43 corresponds for example to a transmitter configured to transmit and receive information and / or data via the communication channel 430. The communication interface 43 corresponds for example to a wired network of the CAN (Controller Area Network) type, CAN FD (Controller Area Network Flexible Data-Rate), FlexRay (standardized by the ISO 17458 standard) or Ethernet (standardized by the ISO / IEC 802-3 standard).

[0133] According to a particular and non-limiting exemplary embodiment, the device 4 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 4.

[0134] [Fig. 5] illustrates a flowchart of the different steps of a method for controlling an AD AS system of a vehicle, for example of the first 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 first vehicle 10 or by the device 4 of [Fig. 4]. The method is for example implemented by one or more processors of one or more computers, for example one or more computers controlling the AD AS system of the vehicle.

[0135] In a first step 51, data representative of an environment surrounding the first vehicle are received from at least one object detection sensor on board the first vehicle.

[0136] In a second step 52, the environment of the first vehicle is spatially subdivided into a plurality of zones, the plurality of zones forming a matrix with 3 rows and 3 columns centered on a central zone comprising the first vehicle, the matrix comprising a central column surrounded on the left by a left column and on the right by a right column.

[0137] In a third step 53, for each zone of the plurality of zones, a presence indicator representative of the presence or absence of a second vehicle is determined as a function of time in each zone based on the data.

[0138] In a fourth step 54, a first vehicle density indicator associated with a first part of the matrix is ​​determined as a function of the presence indicators of the areas included in the first part of the matrix and a second vehicle density indicator associated with a second part of the matrix is ​​determined as a function of the presence indicators of the areas included in the second part. The first part comprises the central column and the left column of the matrix and the second part comprises the central column and the right column of the matrix.

[0139] In a fifth step 55, the AD AS system is controlled according to a third vehicle density indicator, the third vehicle density indicator being a function of the first vehicle density indicator and / or the second vehicle density indicator.

[0140] According to a variant, the variants and examples of the operations described in relation to [Fig.l], 2 and / or 3 apply to the steps of the method of [Fig.5].

[0141] Of course, the present invention is not limited to the exemplary embodiments described above but extends to a method of controlling a vehicle, for example an autonomous vehicle, which would include secondary steps without departing from the scope of the present invention. The same would apply to a device configured for the implementation of such a method.

[0142] The present invention also relates to an AD AS system, for example an adaptive cruise control system for a vehicle, comprising the device 4 of [Fig.4].

[0143] The present invention also relates to a vehicle, for example an automobile or more generally an autonomous land-based motor vehicle, comprising the device 4 of [Fig.4] or the AD AS system for vehicles above.

Claims

1. Claims Method for controlling a driving assistance system, called AD AS system, on board a first vehicle (10), said method comprising the following steps: - reception (51) of data representative of an environment (1) surrounding said first vehicle (10) from at least one object detection sensor on board said first vehicle (10); - spatial subdivision (52) of said environment (1) into a plurality of zones (11 to 19), said plurality of zones forming a matrix with 3 rows and 3 columns centered on a central zone (15) comprising said first vehicle (10), said matrix comprising a central column surrounded on the left by a left column and on the right by a right column; - for each zone of said plurality of zones (11 to 19), determination (53) of a presence indicator representative of the presence or absence of a second vehicle (101, 102, 103, 104) as a function of time in said each zone as a function of said data; - determination (54) of a first vehicle density indicator associated with a first part of said matrix as a function of the presence indicators of the zones (11, 12, 14, 15, 17, 18) included in said first part of the matrix and of a second vehicle density indicator associated with a second part of said matrix as a function of the presence indicators of the zones (12, 13, 15, 16, 18, 19) included in said second part, said first part comprising the central column and the left column of said matrix and said second part comprising the central column and the right column of said matrix; - control (55) of said AD AS system as a function of a third vehicle density indicator, said third vehicle density indicator being a function of said first vehicle density indicator and / or said second vehicle density indicator, characterized in that for each zone, the presence indicator at a current time is equal to the presence indicator at a time preceding the current time to which is added a first positive determined value when a second vehicle is detected in said each zone at the current time and to which is added a second negative determined value when a second vehicle detected in said each zone at said previous time is no longer detected in said each zone at the current time.

2. The method of claim 1, wherein said second determined value corresponds to the opposite of said first determined value or wherein the absolute value of said first determined value is different from the absolute value of said second determined value.

3. Method according to one of claims 1 to 2, for which said first density indicator corresponds to an average of the presence indicators of the zones (11, 12, 14, 15, 17, 18) included in said first part of the matrix and said second density indicator corresponds to an average of the presence indicators of the zones (12, 13, 15, 16, 18, 19) included in said second part of the matrix.

4. Method according to one of claims 1 to 3, for which each zone of said plurality of zones (11 to 19) has a rectangular shape defined by a longitudinal dimension along a longitudinal axis corresponding to a direction of movement of said first vehicle and by a lateral dimension along a lateral axis orthogonal to said longitudinal axis, the longitudinal dimension of the zones of the central line of said matrix comprising said central zone corresponding to a sum of a first determined distance and a second determined distance, the first determined distance corresponding to a distance between a reference point of said first vehicle (10) and a first limit between said central line and a first line of said matrix located in front of said first vehicle (10),the second determined distance corresponding to a distance between said reference point of said first vehicle (10) and a second limit between said central line and a third line of said matrix located behind said first vehicle (10), the longitudinal dimension of the zones (11, 12, 13) of said first line being a function of a first time duration, and the longitudinal dimension of the zones (17, 18, 19) of said third line being a function of a second time duration.,

5. Method according to one of claims 1 to 4, for which said third indicator corresponds: - to an average of said first density indicator and said second density indicator when no indicator of the first vehicle (10) is activated; - to said first density indicator only when a left indicator of said first vehicle (10) is activated; and - to said second density indicator only when a right indicator of said first vehicle (10) is activated.

6. Method according to one of claims 1 to 5, for which said AD AS system corresponds to an adaptive speed regulation system, called ACC system, said method further comprising a determination of an acceleration setpoint for said first vehicle (10) by applying a determined coefficient to a potential acceleration determined by said ACC system, said coefficient being between 0 and 1 and a function of said third vehicle density indicator following a decreasing monotonic function (21) of said third indicator.

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. Device (4) for controlling a driving assistance system, called AD AS system, of a vehicle, said device (4) comprising a memory (41) associated with at least one processor (40) configured for implementing the steps of the method according to any one of claims 1 to 6.

9. Vehicle (10) comprising the device (4) according to claim 8.

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