FR3081140A1 - METHOD AND APPARATUS FOR ASSISTING THE DRIVING OF A VEHICLE HAVING BEFORE IT A LONG VEHICLE WHICH CAN BE DEPORTED TO PASS A TURN - Google Patents

Abstract

A method assists driving a first vehicle (V1) analyzing the environment in front of it. This method comprises a step in which: - the total length of a second vehicle (V2) located in front of the first vehicle (V1), the relative speed of this second vehicle (V2), and the transverse distances are determined at a time t; and longitudinal separating the first (V1) and second (V2) vehicles, then - it is determined an offset that should have at a time t + Δt this second vehicle (V2) to pass a turn because of its total length and the radius of curvature of the turn, then - a representative value of a risk of collision, at this moment t + Δt, between the first (V1) and second (V2) vehicles in the presence of these distances, distances and relative speed is determined, and generates an alert when this determined value is representative of a high collision risk.

Description

METHOD AND DEVICE FOR ASSISTING THE DRIVING OF A VEHICLE HAVING A LONG VEHICLE BEFORE IT MAY DEPART TO TURN A TURN.

The invention relates to vehicles, possibly of the automobile type, which can circulate on roads and which can possibly be driven in an at least partially automated (or autonomous) manner, and more precisely assistance in driving such vehicles.

In what follows, it is considered that a vehicle is driven at least partially automated (or autonomous) when it can be driven automatically (partial or total (without intervention of its driver)) during an automated driving phase, or manually (and therefore with the driver intervening on the steering wheel and / or pedals) during a manual driving phase.

Certain vehicles, generally of the automobile type, include several sensors capable of acquiring environmental information which are used by on-board analysis circuits to reconstruct their environment. This makes it possible to detect neighboring or future neighbor objects, and in particular vehicles, as well as attributes describing these objects, such as for example their relative speed, their trajectory, their transverse (or lateral) distance and their longitudinal distance from the acquiring vehicle. environmental information.

As those skilled in the art know, these reconstructions and the attributes of associated objects are used by at least one assistance device on board the vehicle, for example of the ADAS (“Advanced Driver Assistance System”) type, and responsible for assisting (totally or partially) driving this vehicle, for example by providing information to the driver and / or by controlling at least one member involved in the movements of the vehicle (such as, for example, the power steering, the engine, the gearbox, clutch or braking system).

When a long vehicle, such as a truck or bus, is traveling on a traffic lane and has to pass a turn, its driver must deport it so that this passage can be done without problem. The amplitude of this offset must be greater the longer the vehicle and / or the sharp turn (or its small radius of curvature). However, the greater the amplitude of the offset, the more the long vehicle will encroach on the traffic lane which is adjacent to its own, and therefore the more it risks hindering another vehicle traveling on this adjacent traffic lane, or even of cause an accident if the driver of this other vehicle can only notice this offset late and / or cannot slow it down sufficiently.

If this other vehicle is equipped with a braking assistance device and the offset is detected early enough, the latter will cause a sharp deceleration to avoid the collision, which will cause inconvenience for passengers since they do not have not been previously notified. If the offset of the long vehicle occurs appreciably at the moment when the other vehicle arrives in the offset zone, it is not possible to avoid the collision in an automated manner since there is currently no assistance to avoid a collision in the event of the deportation of another vehicle.

In general, there is currently no assistance device allowing at least early warning of a risk of collision due to a possible offset of a long vehicle present in the vicinity of another vehicle.

The invention therefore aims in particular to improve the situation.

To this end, it notably proposes an assistance method intended to assist the driving of a first vehicle traveling on a road and analyzing the environment in front of it in order to determine first information representative of at least second vehicles present in this environment.

This assistance process is characterized by the fact that it includes a step in which:

- It is determined from first information available at a time t at least a total length of a second vehicle located in front of the first vehicle, a relative speed of this second vehicle relative to the first vehicle, and distances separating this second vehicle from first vehicle in transverse and longitudinal directions thereof, then

- we determine an offset that should have at a time t + At the second vehicle to pass a turn due to this determined total length and a radius of curvature of the turn, then

- a value representative of a risk of collision, at this instant t + At, is determined between the first and second vehicles in the presence of these offset, determined distances and relative speed, and an alert is generated at least when this determined value is representative of a high risk of collision.

Thanks to the invention, when a second long vehicle is located at an instant t in the environment located in front of a first vehicle, it is now possible to determine in advance whether there is a risk of collision between these first and second vehicles. at time t + At in the event of this second long vehicle being offset.

The assistance method according to the invention may include other characteristics which can be taken separately or in combination, and in particular:

- in its stage, the offset can be determined when the determined total length is greater than a predefined length threshold and when the radius of curvature of the turn is less than a predefined radius threshold;

- in its stage, it is possible to determine the radius of curvature as a function of first information representative of the turn and / or of environmental information defining the environment in front of the first vehicle;

in its stage, it is possible to determine a transverse position of the first vehicle with respect to the delimitations of a traffic lane of the road on which it is traveling, according to the first information available, then it is possible to determine the value of risk of collision function of a difference between this determined transverse position and the determined offset in this traffic lane for the moment t + At;

- in its stage, it is possible to alert a driver of the first vehicle to the risk of collision represented by the value determined by means of a text message displayed on at least one screen of the first vehicle and / or of an audible message broadcast by at least one loudspeaker of said first vehicle;

- in its stage, after the generation of the alert, it is possible to adapt the speed and / or trajectory of the first vehicle so that the latter is not hampered by the offset at the instant t + At.

The invention also provides a computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing a method of assistance of the type presented above for assist driving a first vehicle traveling on a road.

The invention also provides an assistance device intended to equip a first vehicle traveling on a road and comprising analysis circuits analyzing the environment in front of it in order to determine first information representative of at least second vehicles present in this environment.

This assistance device is characterized by the fact that it includes a processor:

- determining from the first information available at a time t at least a total length of a second vehicle located in front of the first vehicle, a relative speed of the second vehicle relative to the first vehicle, and distances separating this second vehicle from the first vehicle along transverse and longitudinal directions of the latter, then

- determining an offset that the second vehicle should have at an instant t + At to pass a turn due to this determined total length and a radius of curvature of the turn, then

- determining a value representative of a risk of collision, at this instant t + At, between the first and second vehicles in the presence of these offset, determined distances and relative speed, and triggering the generation of an alert at least when said value determined is representative of a high risk of collision.

The invention also provides a vehicle, possibly of the automobile type, suitable for traveling on a road, and comprising analysis circuits analyzing the environment in front of it in order to determine first information representative of at least second vehicles present in this environment. This vehicle is characterized by the fact that it further includes an assistance device of the type presented above.

Other characteristics and advantages of the invention will appear on examining the detailed description below, and the attached drawings, in which:

- Figure 1 schematically and functionally illustrates at a time t a portion of a first road comprising two lanes on which respectively circulate a first vehicle, equipped with a driving assistance device according to the invention, and a second long vehicle, and

- Figure 2 illustrates schematically and functionally at a time t + At another portion of the first road in Figure 1 intersected at 90 ° by a portion of a second road joined by the second long vehicle.

The object of the invention is in particular to propose an assistance method, and an associated assistance device DA1, intended to assist the driving of a first vehicle V1 traveling on a road R1 and having a second long vehicle V2 in the environment that is located in front of him.

In what follows, it is considered, by way of nonlimiting example, that the first vehicle V1 is of the automobile type. This is for example a car. However, the invention is not limited to this type of vehicle. It concerns in fact any type of vehicle which can circulate on land traffic lanes.

There is schematically and functionally shown in FIG. 1 a first portion of a first road R1 comprising first VC1 and second VC2 taxiways having identical traffic directions. Note that the two traffic lanes VCk (k = 1 or 2) could have opposite traffic directions, and that the first road R1 could have more than two traffic lanes.

In the example illustrated without limitation, the second vehicle V2 (long) travels on the first taxiway VC1 (this is for example a bus or a truck), and the first vehicle V1 travels on the second taxiway VC2, which is here an passing lane adjacent to the first taxiway VC1.

As illustrated in FIG. 2, the first route R1 comprises a second portion, located just after its first portion, and intersected (here at 90 °) by a second route R2. The latter (R2) here also includes first VC3 and second VC4 traffic lanes having, for example, opposite traffic directions.

The first vehicle V1 is notably equipped with CAN analysis circuits and an exemplary embodiment of a DA1 assistance device according to the invention.

The CAN analysis circuits are arranged so as to analyze the environment at least in front of the first vehicle V1 in order to determine first information which is representative of at least second vehicles V2 present in this environment (and in particular of their attributes (length Iv2 , relative speed vr with respect to V1, trajectory, distances dt and dl with respect to V1 in transverse and longitudinal directions of the latter (V1))). It will be noted that they can also, possibly, determine other first information representative of their environment, such as for example markings on the ground of the first road R1 (and in particular the delimitations of the traffic lanes VCk), the curvature of a portion of the first road R1, the number of traffic lanes VCk of the first road R1, an entry and / or exit from the first road R1, traffic signs of the first road R1, a tunnel on the first road R1 , traffic lights of the first road R1, safety rails of the first road R1, emergency stop strips of the first road R1, or buildings.

The environment which is at least located in front of the first vehicle V1, and which is analyzed by the CAN analysis circuits, is defined (or represented) by data acquired by sensors CPj which are fixedly secured to the first vehicle V1 in suitable places for this purpose. In order for the invention to be implemented, the sensors CPj must comprise, on the one hand, at least one front camera acquiring digital images in front of the first vehicle V1, from which can be deduced in particular from the longitudinal and transverse distances and possibly radii of curvature (in the presence of information provided by road maps), and, on the other hand, ultrasound analysis circuits and / or scanning lasers and / or radars or lidars acquiring information in particular speed and distance. This front camera constitutes (or is part of) the first sensors CP1 (j = 1) and is, for example, secured to the windshield PB, preferably in its upper (or upper) part, or else in the interior central rear view mirror of the first vehicle V1. The ultrasonic analysis circuits and / or scanning lasers and / or radars or lidars constitute (or form part of) second CP2 sensors (j = 2) and are, for example, secured to the shield (or bumper) before.

The use of different types of CPj sensors overcomes any shortcomings of these different types (notably that of the lidar in the rain, that of the camera in the snow, and that of the range of a radar or lidar).

In the example illustrated without limitation in the single figure, the CAN analysis circuits are part of a CAL computer. But it is not compulsory. Indeed, the CAN analysis circuits could include their own computer. Consequently, the CAN analysis circuits can be implemented in the form of software modules (or computer or even "software"), or a combination of electrical or electronic circuits or components (or "hardware") and modules software.

As mentioned above, the invention proposes in particular an assistance method intended to assist the driving of the first vehicle V1 when it is traveling on the first road R1 and there is a second long vehicle V2 traveling in the environment. located in front of him (V1).

The term “second vehicle traveling in the environment in front of it” is understood here to mean a second vehicle V2 traveling on a lane of a first road R1 on which the first vehicle V1 travels, in the same direction as the latter (V1 ) or in a direction opposite to that of the latter (V1), or else traveling on a lane of a second road R2 intersecting a first road R1 on which the first vehicle V1 travels, and preparing to join this first road R1.

This assistance method can be at least partially implemented by the assistance device DA1 which for this purpose comprises at least one digital signal processor (or DSP ("Digital Signal Processor")) PR.

In the example illustrated without limitation in the single figure, the assistance device DA1 is part of the computer CAL which also includes the CAN analysis circuits. But it is not compulsory. Indeed, it could be part of another calculator than the CAL calculator, or could include its own calculator. Consequently, the assistance device DA1 can be produced in the form of software modules, or of a combination of electrical or electronic circuits or components and software modules.

The assistance method according to the invention comprises a step in which one (the processor PR) begins by determining on the basis of first information, which is available at a time t (and originating from the CAN analysis circuits), at minus the total length Iv2 of a second vehicle V2 located in front of the first vehicle V1, a relative speed vr of this second vehicle V2 relative to the first vehicle V1, and the transverse distances dt and longitudinal dl separating this second vehicle V2 from the first vehicle V1 along respectively transverse and longitudinal directions of the latter (V1).

It is important to note that the second vehicle V2 can travel on a traffic lane adjacent to that of the first vehicle V1 and in the same direction as that of the latter (V1) as in the example illustrated without limitation in FIG. 1, or in a direction opposite to that of the first vehicle V1, or else on a traffic lane of a second road R2 intersecting a first road R1 having a traffic lane on which the first vehicle V1 travels.

Furthermore, the transverse distance dt is, for example, the smallest value of the projections along the transverse direction of the first vehicle V1 of the distance vectors connecting the front corner of the second vehicle V2 adjacent to the front corner of the first vehicle V1 on the axis coincides with the front end of the first vehicle V1, and the rear corner of the second vehicle V2 adjacent to the front corner of the first vehicle V1 on the axis coincides with the front end of the first vehicle V1. Similarly, the longitudinal distance dl is, for example, the smallest value of the projections along the transverse direction of the first vehicle V1 of the distance vectors connecting the front corner of the second vehicle V2 adjacent to the front corner of the first vehicle V1 on the axis coincident with the side of the first vehicle V1 adjacent to the second vehicle V2, and the rear corner of the second vehicle V2 adjacent to the front corner of the first vehicle V1 on the axis coincident with the side of the first vehicle V1 adjacent to the second vehicle V2.

Then, in the process step we (the PR processor) determines an offset dv2 that the second vehicle V2 should have at an instant t + At to pass a turn (staying on the roadway) because of its determined total length Iv2 and the radius of curvature rc of this turn.

An example of dv2 offset, in the second lane of traffic VC2 of a first road R1, of a second vehicle V2, passing a right turn intended to allow it to pass from the first lane of traffic VC1 of the first road R1 to the first taxiway VC3 of a second road R2, is illustrated in FIG. 2. The remote trajectory td which is forced to follow the second vehicle V2 to join without problem the first taxiway VC3 of the second route R2 is also shown in FIG. 2, by way of example.

Then, in the process step, we (the processor PR) determines a value vrc which is representative of a risk of collision, at this instant t + At, between the first V1 and second V2 vehicles in the presence of these offset dv2, transverse distances dt and longitudinal dl, and relative speed vr determined. Then, an alert is generated at least when this vrc value is representative of a high risk of collision. This generation is triggered by the PR processor.

For example, this value vrc may be a time before collision in the event of the second vehicle V2 being offset. The time before collision vrc is here equal to the longitudinal distance dl divided by the instantaneous relative speed. In this case, it is considered that the risk of collision is high when the time before collision vrc is less, for example, at 3 seconds and that the transverse distance dt (in the event of offset) is less than 0. It is also possible to provide for a medium collision risk when the time before collision vrc is between 3 seconds and 5 seconds, and the transverse distance dt (in case of offset) is less than 0. In this case, there will be at least two alert levels, one high when we have vrc <3 s and dt <0, the other medium when we have 3 s <vrc <5 s and dt <0.

As a variant, the value vrc can, for example, be a percentage of risk of collision when the transverse distance dt (in the case of offset) is less than 0. In this case, there is a high risk of collision when the value vrc is greater than a risk threshold sr1, for example, between 10% and 20%.

Thus, when a second long vehicle V2 is placed at an instant t in the environment located in front of a first vehicle V1, we can now determine in advance whether there is a risk of collision between these first V1 and second V2 vehicles at time t + At in the event of a dv2 offset from this second vehicle V2, in order to generate an alert in the affirmative.

In the example illustrated without limitation in FIG. 2, it can be observed that at time t + At the offset dv2 of the second vehicle V2 in the second lane of traffic VC2 taken by the first vehicle V1 is very important (typically the half the width of VC2), and therefore the first vehicle V1 is likely to collide with the remote rear part (of dv2) of the second vehicle V2 if the latter (V2) started its right turn just before this moment t + At.

It will be noted that in the process step we (the processor PR) can determine the offset dv2 for time t + At, only when the total length Iv2 determined is greater than a length threshold if predefined and when the radius of curvature rc of the turn is less than a predefined radius threshold sr2 (ie if Iv2> if and rc> sr2). In fact, the amplitude of the dv2 offset is all the greater since the second vehicle V2 is long and the cornering tight (or its radius of curvature rc small).

For example, the length threshold si can be between 450 cm and 2500 cm.

It will also be noted that in the process step we (the processor PR) can determine the radius of curvature rc of the turn as a function of first information representative of this turn and / or of environmental information which define the environment in front of the first vehicle V1.

It will be understood that this requires that the CAN analysis circuits be capable of determining taxiway delimitations among the digital images acquired by the camera (s) of the first sensors CP1, and that the CAN analysis circuits are capable of determining the radius of curvature rc of the bend as a function of these determined delimitations, or that the processor PR is capable of determining the radius of curvature rc of the bend as a function of these determined delimitations. Furthermore, the environmental information which defines the environment in front of the first vehicle V1, and in particular the turns of the traffic lanes of the roads, can be provided by a cartographic database on board the first vehicle V1 (and making by example part of a navigation aid device), and / or by a cartographic information supply site accessible by waves by a communication module on board the first vehicle V1.

It will also be noted that in the process step one (the processor PR) can determine a transverse position pt of the first vehicle V1 relative to the delimitations of the traffic lane VCk (here VC2) of the first road R1 on which it is traveling, according to the first information available. It will be understood that this requires that the CAN analysis circuits are capable of determining these delimitations among the digital images acquired by the camera (s) of the first sensors CP1. Then, we (the processor PR) can determine the collision risk value vrc as a function of the difference between this determined transverse position pt and the offset dv2 determined in this traffic lane VCk (here VC2) for the moment t + At This determination of vrc is identical to that described above.

It will also be noted that in the process step one (the processor PR) can alert the driver of the first vehicle V1 of the risk of collision represented by the value vrc determined by means of a text message displayed on at least one screen of the first vehicle V1 and / or an audible message broadcast by at least one speaker of the first vehicle V1. The screen can, for example, be that of the dashboard or that of the CC central handset which is installed in or on the PDB dashboard. For example, the alert can signal a risk of collision with the second vehicle V2 in At seconds in the absence of slowing and / or modification of the trajectory of the first vehicle V1.

As a variant or in addition, in the process step, after the generation of the alert, the speed and / or the trajectory of the first vehicle V1 can be adjusted so that the latter (V1) is not hampered by the dv2 offset at the instant t + At. This option can only be implemented in the first vehicle V1 provided that its driving is at least partially automated (or autonomous), and therefore that it can be driven automatically ( partial or total (without driver intervention)) during an automated driving phase, or manually (and therefore with driver intervention on the steering wheel and / or pedals) during a manual driving phase. The first V1 vehicle must therefore have a function controlling at least one member involved in its movements, such as, for example, its power steering, its engine, its gearbox, its clutch, or its braking system. This function can be ensured by another assistance device DA2 equipping the first vehicle V1, as illustrated in FIG. 1, or by the assistance device DA1 (which requires that it also comprises control means) .

In the example illustrated without limitation in FIG. 1, the other assistance device DA2 is part of the computer CAL which also includes the assistance device DA1 and the CAN analysis circuits. But it is not compulsory. Indeed, this other DA2 assistance device could be part of another computer than the CAL computer, or could include its own computer. Consequently, the other DA2 assistance device can be produced in the form of software modules, or a combination of electrical or electronic circuits or components and software modules. In the presence of such another DA2 assistance device, it is the processor PR which triggers the alert of the first (DA2).

It will also be noted that the invention also provides a computer program product comprising a set of instructions which, when executed by processing means of electronic circuits (or hardware) type, such as for example a part at least of the processor PR, is capable of implementing the assistance method described above to assist the driving of the first vehicle V1 when it is traveling on the first road R1.

It will also be noted that in FIG. 1 the assistance device DA1 is very schematically illustrated with only its processor PR. This DA1 assistance device can take the form of a box comprising printed circuits, or of several printed circuits connected by wired or non-wired connections. By printed circuit is meant any type of device capable of performing at least one electrical or electronic operation. As mentioned above, this assistance device DA1 can, for example, include a digital signal processor (or DSP (Digital Signal Processor)), a random access memory for storing instructions for the implementation by this processor of the method of assistance as described above, and a mass memory for the storage of data intended to be kept after the implementation of the assistance method. The digital signal processor can be the processor PR, and therefore receives at least the first information determined by the CAN analysis circuits to analyze it and use it in calculations, possibly after having formatted and / or demodulated it and / or amplified, in a manner known per se. The DA1 assistance device can also include an input interface for receiving at least the first determined information, and an output interface for transmitting the results of its analyzes and calculations.

One or more sub-steps of the assistance process step can be carried out by different components. Thus, the assistance method can be implemented by a plurality of processors, random access memory, mass memory, input interface, output interface and / or digital signal processor. In these situations, the DA1 assistance device can be decentralized, within a local network (several processors linked together for example) or a wide area network.

Claims (10)

1. Method for assisting in driving a first vehicle (V1) traveling on a road (R1) and analyzing the environment in front of it in order to determine first information representative of at least second vehicles (V2) present in this environment , characterized in that it comprises a step in which a) a speed is determined from the first information available at a time t at least a total length of a second vehicle (V2) located in front of said first vehicle (V1) relative of said second vehicle (V2) with respect to said first vehicle (V1), and of the distances separating said second vehicle (V2) from said first vehicle (V1) in transverse and longitudinal directions of the latter (V1), then b) it is determined an offset that should have at a time t + At said second vehicle (V2) to pass a turn due to said determined total length and a radius of curvature of said turn, then c) det ermines a value representative of a risk of collision, at said instant t + At, between said first (V1) and second (V2) vehicles in the presence of said offset, determined distances and relative speed, and an alert is generated at least when said value determined is representative of a high risk of collision. 2. Method according to claim 1, characterized in that in said step one determines said offset when said determined total length is greater than a predefined length threshold and when said radius of curvature of said turn is less than a predefined radius threshold. 3. Method according to one of claims 1 or 2, characterized in that in said step one determines said radius of curvature according to first information representative of said turn and / or environmental information defining said environment in front of the first vehicle (V1). 4. Method according to one of claims 1 to 3, characterized in that in said step a transverse position of said first vehicle (V1) is determined with respect to the delimitations of a traffic lane (VCk) of said road (R1 ) on which it circulates, as a function of the first available information, then said value is determined as a function of a difference between said determined transverse position and the offset determined in this traffic lane (VCk) for said instant t + At. 5. Method according to one of claims 1 to 4, characterized in that in said step a driver of said first vehicle (V1) is alerted of said risk of collision represented by said determined value by means of a text message displayed on at least a screen of said first vehicle (V1) and / or a sound message broadcast by at least one speaker of said first vehicle (V1). 6. Method according to one of claims 1 to 5, characterized in that in said step after said alert generation, a speed and / or a trajectory of said first vehicle (V1) is adapted so that the latter (V1) is not not bothered by said offset at said instant t + At. 7. Computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing the assistance method according to one of the preceding claims to assist the conduct of a first vehicle (V1) traveling on a road (R1). 8. Assistance device (DA1) for a first vehicle (V1) traveling on a road (R1) and comprising analysis circuits (CAN) analyzing the environment in front of it in order to determine first information representative at least of seconds vehicles (V2) present in this environment, characterized in that it comprises a processor (PR) a) determining from first information available at a time t at least a total length of a second vehicle (V2) located in front of said first vehicle (V1), a relative speed of said second vehicle (V2) with respect to said first vehicle (V1), and distances separating said second vehicle (V2) from said first vehicle (V1) in transverse and longitudinal directions thereof ( V1), then b) determining an offset that said second vehicle (V2) should have at an instant t + At to pass a turn due to said determined total length and a radius of curvature d said turn, then c) determining a value representative of a risk of collision, at said instant t + At, between said first (V1) and second (V2) vehicles in the presence of said offset, determined distances and relative speed, and triggering the generation of an alert at least when said determined value is representative of a high risk of collision. 9. Vehicle (V1) capable of traveling on a road (R1) and comprising analysis circuits (CAN) analyzing the environment in front of it in order to determine first information representative at least of seconds 5 vehicles (V2) present in this environment, characterized in that it further comprises an assistance device (DA1) according to claim 8. 10. Vehicle according to claim 9, characterized in that it is of the automobile type.