EP4313706A1

EP4313706A1 - System for driving in autonomous mode upstream of a change in the maximum allowed speed

Info

Publication number: EP4313706A1
Application number: EP22707804.5A
Authority: EP
Inventors: Thibault Griffon
Original assignee: Stellantis Auto SAS
Current assignee: Stellantis Auto SAS
Priority date: 2021-03-23
Filing date: 2022-02-04
Publication date: 2024-02-07
Also published as: FR3121109A1; WO2022200696A1; FR3121109B1

Abstract

System allowing a vehicle (1) to be driven in autonomous mode on a road (20) comprising a change in a maximum allowed speed from a first maximum allowed speed (V1) to a second maximum allowed speed (V2) higher than the first, this system comprising - a plurality of sensors able to - detect said change in the maximum allowed speed; - measure a distance between the vehicle (1) and another vehicle (2) following it; - determine that a lane change is not possible for the vehicle; - a computer configured to generate a setpoint speed lower than a predefined threshold speed; - the predefined threshold speed being, when - said change in the maximum allowed speed is detected, - the measured distance is shorter than a predefined distance, - a lane change is not possible, higher than the first maximum allowed speed (V1).

Description

Title of the invention: Driving system in autonomous mode upstream of a change in the maximum authorized speed

The present invention claims the priority of French application 2102879 filed on March 23, 2021, the content of which (text, drawings and claims) is incorporated herein by reference. The present invention relates to autonomous vehicles, and more particularly to autonomous driving systems.

[0002] Just like a human driver, an autonomous driving system is required to comply with the rules of the Highway Code, including in particular speed limits. In this regard, the autonomous driving system is configured to determine the maximum authorized speed applicable to the current position of the motor vehicle and to adapt its speed so that it does not exceed the maximum authorized speed. When this maximum authorized speed changes at a given position of the road, the autonomous driving system detects this change and consequently regulates the speed of the motor vehicle from this position. A change in the maximum authorized speed may be signaled by a new speed limit applicable from this position or by the end of a speed limit applicable upstream of this position. The autonomous driving system adapts the speed of the motor vehicle so as to scrupulously respect the speed limit applicable to the current position of the motor vehicle both upstream and downstream of the position of the change of the maximum authorized speed and independently that this change either to a higher or lower maximum permitted speed.

[0003] However, when the new maximum authorized speed is greater than the previous one, drivers often anticipate this change and accelerate when approaching the position of the road marking this change in the maximum authorized speed, ie. before they come up to that road position.

[0004] Consequently, anticipation by drivers of a change in a speed limit, on the one hand, and compliance Strict and scrupulous speed limits by autonomous driving systems, on the other hand, are likely to create risky situations for all road users.

An object of the present invention is to avoid the risk of collision immediately upstream of a change in the maximum authorized speed on a road.

Another object of the present invention is to adapt the speed of a motor vehicle in autonomous driving approaching a change in a regulatory speed limit to take account of the behavior of surrounding motor vehicles.

[0007] To this end, it is proposed, firstly, an autonomous driving system allowing driving in autonomous mode of a first motor vehicle on a road comprising at least a first traffic lane having a traffic direction and comprising a change of a maximum speed authorized on this road from a first maximum speed authorized upstream, with respect to said direction of travel, of a predefined position of this road, to a second maximum speed authorized downstream, with respect to said direction of circulation, from said predefined position, the second maximum authorized speed being greater than the first maximum authorized speed, this system comprising

- At least a first sensor capable of detecting, when the first motor vehicle is on the road upstream of said predefined position, said change in the maximum authorized speed;

- At least one second sensor capable of measuring a first distance between the first motor vehicle and a second surrounding motor vehicle following said first motor vehicle on said at least one first lane;

- At least one third sensor capable of determining that a lane change is impossible for the first motor vehicle;

- a computer configured to generate a setpoint speed for the first motor vehicle, this setpoint speed being lower than a predefined threshold speed;

- the predefined threshold speed is, when said change in the maximum authorized speed is detected, the first distance measured is less than a first predefined safety distance, a lane change is impossible for the first motor vehicle, greater than the first maximum authorized speed.

[0008] Various additional characteristics may be provided, alone or in combination:

- the threshold speed is lower than the second authorized maximum speed;

- said at least one third sensor is further able to determine that a lane change is possible for the first motor vehicle, the computer being configured to generate, when the first motor vehicle is on the road upstream of said position predefined; the predefined threshold speed is greater than the first authorized maximum speed, a lane change instruction;

- the system further comprises at least one fourth sensor capable of measuring a second distance between the first motor vehicle and a surrounding third motor vehicle preceding said first motor vehicle on said at least one first lane, the setpoint speed generated being defined so that the second measured distance is greater than a second predefined safety distance;

- the first sensor is an image sensor configured to detect a change in the maximum authorized speed signaled by a road sign;

- the first sensor comprises a vehicle communication module configured to receive information concerning a change in the maximum authorized speed;

- the information received comprises the first authorized maximum speed, the second authorized maximum speed, location data of said position;

- the first sensor comprises a geolocation and navigation module; - the system further comprises a first actuator capable of acting on the speed of the motor vehicle to reach the setpoint speed generated by the computer.

[0009] It is proposed, secondly, a motor vehicle comprising the autonomous driving system presented above.

Other characteristics and advantages of the invention will appear more clearly and concretely on reading the following description of embodiments, which is made with reference to the accompanying drawings in which:

Figure [Fig.1] schematically illustrates a motor vehicle integrating an autonomous driving system according to various embodiments;

The figure [Fig.2] schematically illustrates a context of use of an autonomous driving system according to various embodiments.

[0013] Referring to the appended figures, a motor vehicle 1 capable of implementing an autonomous driving mode is displayed. This motor vehicle 1 is, in fact, equipped with an autonomous driving system 10 allowing driving in autonomous mode of this motor vehicle 1 on a road 20.

The road 20 comprises at least one lane 21 -23 of traffic having a direction 24 of traffic. This route 20 includes a position 25 at which there is a change in the maximum authorized speed. In other words, route 20 includes a change in the maximum authorized speed from a first maximum authorized speed V1 upstream, relative to said direction 24 of traffic, from position 25 of this route 20, to a second maximum authorized speed V2 in downstream, with respect to said direction 24 of circulation, of position 25. The speeds V1,

V2 maximum authorized on either side of position 25 of route 20 are different. In one embodiment, the second maximum authorized speed V2 is greater than the first maximum authorized speed V1.

[0015] Position 25 marks, in one embodiment, a change in the maximum authorized speed (or applicable speed limits) between two sections of road 20, two different traffic areas connected by road 20, or between two different types of route 20 (national road, departmental road, or highway for example). This change in the maximum authorized speed may be signaled by a traffic sign placed at position 25, or by a traffic sign accompanied by a distance sign and placed upstream, with respect to the direction of travel 24, from position 25 by a predefined distance. As an alternative or in combination, information concerning this change in the maximum authorized speed can be broadcast to users of the road 20 by a road infrastructure covering this road 20 or provided by a geolocation and navigation module on board the vehicle 1 automobile. This information includes a first and a second maximum authorized speed V1, V2 and location data for the position 25 of the road 20 marking this change in the maximum authorized speed on this road 20 (end of a speed limit or the start a new speed limit).

The autonomous driving system 10 comprises at least one sensor 13a-13i able to detect, when the motor vehicle 1 is on the road 20 upstream of the position 25, the change in the maximum authorized speed. More generally, the autonomous driving system 10 comprises one or more sensors 13a-13i capable of determining, when the motor vehicle 1 is approaching position 25, the second maximum authorized speed V2 applicable from this position 25 to the place of the first authorized maximum speed V1 still applicable up to this position 25 of the road 20. These sensors 13a-13i make it possible to detect in advance the start of a new speed limit or the end of the speed limit. current speed at a position 25 of the road 20 in front of the motor vehicle 1.

[0017] By comparing the current speed limit to the next speed limit applicable from position 25 of the road 20, the sensors 13a-13i allow the detection of an imminent increase in the maximum speed authorized on the road. 20.

[0018] Sensors 13a-13i used by the autonomous driving system 10 for detecting a change in speed speed limit comprise, for example, an image sensor (in particular, a front camera) configured to detect a change in the maximum speed limit indicated by a road sign, a vehicle communication module (of the vehicle-with-all better known by the English name "Vehicle-to-Everything", Vehicle-to-Vehicle, Vehicle-to-Dispositif, Vehicle-to-lnfrastructure, or Vehicle-to-Network for example) configured to receive information concerning a change of the maximum authorized speed on route 20, and/or a geolocation and navigation module (a geolocation sensor of the GPS, GLONASS type, or equivalent provided with cartographic data concerning route 20). These sensors are, in one embodiment, arranged at the front or on the roof of the motor vehicle 1 .

[0019] In one embodiment, communication from the infrastructure to a sensor 13a-13i on board the motor vehicle 1 (Infrastructure-to-Vehicle or I2V) makes it possible to indicate to it, when it is upstream of the position 25 less than a predefined distance, the second maximum authorized speed V2 and the position 25 from which this new speed limit is applicable.

The autonomous driving system 10 further comprises at least one sensor 13 a- 13 i able to measure the distance (or inter distance) between the motor vehicle 1 and a surrounding motor vehicle 2 following this motor vehicle 1 on the same lane 21 of traffic. These sensors 13a-13i make it possible to detect the passage of this distance below a predefined safety distance. Sensors 13a-13i used by the autonomous driving system 10 to measure this distance include, for example, a vehicle communication module, ultrasonic sensors, radars, and/or lidars. These sensors are, in one embodiment, arranged at the rear or on the roof of the motor vehicle 1.

Furthermore, the autonomous driving system 10 comprises at least one sensor 13a-13i capable of determining whether a lane change is possible or impossible for the motor vehicle 1. These sensors 13a-13i make it possible, in fact, to detect whether there is at least one traffic lane 22-23 adjacent to the current traffic lane 21 of the motor vehicle 1 and, if this is the case (i.e. .d. a multi-lane road 20), to determine whether a change of lane of the motor vehicle 1 to one of the adjacent traffic lanes 22-23 is possible or not. In particular, these sensors 13a-13i are able to determine that a lane change (in particular, a folding maneuver) is impossible for the motor vehicle 1. A lane change may, in fact, be impossible for the motor vehicle 1 when the road 20 comprises a single traffic lane (a single-lane road 20) or in the presence of a surrounding motor vehicle 3-6 on the lane 22 -23 of adjacent traffic preventing the motor vehicle 1 to make a safe lane change to this lane 22-23 of adjacent traffic. In the presence of two adjacent traffic lanes 22-23 on either side of the current traffic lane 21 of the motor vehicle 1, the sensors 13a-13i are able to determine that neither a secure lane change to the lane 22 of right traffic nor a secure lane change to the left traffic lane 23 is possible for the motor vehicle 1.

[0022] Sensors 13a-13i used by the autonomous driving system 10 to determine that a lane change is impossible for the motor vehicle 1 include radars, lidars, a vehicle communication module, and/or a sensor of picture. These sensors are, in one embodiment, arranged on the side faces, at the rear and/or on the roof of the motor vehicle 1 .

In another embodiment, the autonomous driving system 10 further comprises at least one sensor 13a-13i capable of measuring the distance between the motor vehicle 1 and a surrounding motor vehicle 7 preceding this motor vehicle 1 on the same lane 21 of traffic. These sensors 13a-13i make it possible to detect the passage of this distance below a predefined safety distance. Sensors 13a-13i used by the autonomous driving system 10 to measure this distance comprise, for example, a module of vehicular communication, ultrasonic sensors, radars, and/or lidars. These sensors are, in one embodiment, arranged at the front or on the roof of the motor vehicle 1 .

The autonomous driving system 10 includes a computer 11 configured to interpret the data provided by the sensors 13a-13i and generate a set speed for the motor vehicle 1 below a predefined threshold speed. The generation of a setpoint speed by the computer 11 satisfies a constraint according to which this setpoint speed must be lower than the predefined threshold speed. This threshold speed is, by default, chosen equal to the maximum speed authorized at the current position of the motor vehicle 1 .

[0025] In one embodiment, when it is detected by the sensors 13a-13i

- an imminent change in the maximum authorized speed,

- a distance between the motor vehicle 1 and the motor vehicle 2 surrounding the next one less than a predefined safety distance, and

- A lane change impossible for the motor vehicle 1, the threshold speed is chosen to be greater than the first authorized maximum speed V1. In other words, the computer 11 changes, under these conditions, the value of the threshold speed. For example, the threshold speed is chosen to be 3%, 5% or 10% higher than the first authorized maximum speed V1. The motor vehicle 1 can thus have, upstream of the position 25 of the road 20, a speed greater than the first authorized maximum speed V1.

Under these conditions, a set speed greater than the first maximum authorized speed V1 advantageously makes it possible to avoid a risky situation created by the surrounding motor vehicle 2 following the motor vehicle 1. By increasing its speed, remaining in its traffic lane 21, and respecting a safety distance with the motor vehicle 2 surrounding the following one, the motor vehicle 1 avoids a collision with the motor vehicle 2 surrounding the following one. The threshold speed is, in one embodiment, lower than the second maximum authorized speed V2. The motor vehicle 1 thus anticipates the second maximum authorized speed V2 without exceeding it.

In the presence of a surrounding motor vehicle 7 preceding the motor vehicle 1 on the traffic lane 21, the setpoint speed generated is defined so that the distance between these two motor vehicles 1, 7 is greater than a distance of predefined security.

[0029] Such a configuration of the computer 11 advantageously improves the autonomous driving mode of the motor vehicle 1 when approaching a gear change and without the possibility of falling back or overtaking, thanks to an understanding of the driving context and the behavior of surrounding motor vehicles 2-7.

[0030] It should be noted that this configuration of the computer 11 aims to provide an automatic safety maneuver to secure the occupants of the motor vehicle 1 and those of the surrounding motor vehicles 2-7 in predefined extreme situations (for example, a inter-distance between vehicles 1 -2 automobiles less than 20%, 10% or 5% of a predefined safety distance). Alternatively, a request to resume driving can be sent to the driver of motor vehicle 1 before modifying the value of the threshold speed. In the absence of action on the part of the driver at the end of a countdown, the computer 11 increases the value of the threshold speed. In another embodiment, this configuration of the computer 11 is offered as an option that the user can, under his sole and entire responsibility, activate.

The autonomous driving system 10 comprises at least a first actuator 12a able to act on the speed (i.e. on the accelerator and/or on the braking system) of the motor vehicle 1 to reach the speed setpoint generated by the computer 11 . The autonomous driving system 10 further comprises at least one second actuator 12b capable of acting on the direction of the motor vehicle 1 in order to control its trajectory, in particular to make a lane change.

In one embodiment, the computer 11 is configured to generate a lane change instruction (to the left lane or to the right lane) as soon as it is determined by the sensors 13a-13 i that a lane change has become possible for motor vehicle 1. The automobile vehicle 1 can thus carry out a folding maneuver (in particular, depending on the type of driving on the left or on the right) and reduce its speed below the first authorized maximum speed V1 as long as it has not yet reached the position 25 of the road 20. More generally, when it is determined by the sensors 13a-13i that a lane change is possible for the motor vehicle 1, a lane change instruction is issued by the computer 11 in order to bring the speed of motor vehicle 1 below the first maximum authorized speed V1 upstream of position 25 of road 20.

As illustrated in Figure 2, when approaching a change in the applicable speed limit (recognized by communication with the infrastructure, by visual capture of road signs and / or by geolocation and navigation), the surrounding motor vehicles 2-7 increase their speed beyond the first maximum authorized speed V1 before arriving at position 25 of the road 20 of the change in the maximum authorized speed, then the motor vehicle 1 adapts its speed so as not to have dangerous driving behavior. As long as it is not possible for it to perform a lane change manoeuvre, the motor vehicle 1 follows the speed of the surrounding motor vehicles 2-7.

In one embodiment, the computer 11 is a software application or, more generally, a computer program product installed on a computer processing unit of the autonomous driving system 10.

[0035] Advantageously, the autonomous driving system 10 described above makes it possible to reduce the risk of accidents and therefore provides a gain in safety for road users. This autonomous driving system 10 also makes it possible to avoid risky situations following an increase in the speed of the surrounding motor vehicles in anticipation of an increase in the maximum authorized speed.

Claims

[Claim 1] Autonomous driving system (10) allowing driving in autonomous mode of a first motor vehicle (1) on a road (20) comprising at least a first traffic lane (21) having a direction (24) of traffic and comprising a change of a maximum speed authorized on this road (20) of a first maximum speed (VI) authorized upstream, with respect to said direction (24) of traffic, of a predefined position (25) of this road (20), at a second maximum authorized speed (V2) downstream, relative to said direction (24) of travel, from said predefined position (25), the second maximum authorized speed (V2) being greater than the first speed ( VI) maximum authorized, this system (10) comprising

- At least one first sensor (13a-13i) capable of detecting, when the first motor vehicle (1) is on the road (20) upstream of said predefined position (25), said change in the maximum authorized speed;

- at least one second sensor (13a-13i) capable of measuring a first distance between the first motor vehicle (1) and a second surrounding motor vehicle (2) following said first motor vehicle (1) on said at least one first lane ( 21) traffic;

- At least one third sensor (13a-13i) capable of determining that a lane change is impossible for the first motor vehicle (1);

- a computer (11) configured to generate a set speed for the first motor vehicle (1), this set speed being lower than a predefined threshold speed; this system being characterized in that the predefined threshold speed is, when

- said change in the maximum authorized speed is detected,

- the first distance measured is less than a first predefined safety distance,

- A lane change is impossible for the first vehicle (1) automobile, higher than the first speed (VI) maximum authorized.

[Claim 2] System according to the preceding claim, characterized in that the threshold speed is lower than the maximum authorized second speed (V2).

[Claim 3] System according to Claim 1 or 2, characterized in that the said at least one third sensor (13a-13i) is, in addition, able to determining that a lane change is possible for the first motor vehicle (1), the computer (11) being configured to generate, when

- the first motor vehicle (1) is on the road (20) upstream of said predefined position (25);

- the predefined threshold speed is greater than the first maximum authorized speed (VI), a lane change instruction.

[Claim 4] System according to any one of the preceding claims, characterized in that it further comprises at least one fourth sensor (13a-13i) capable of measuring a second distance between the first motor vehicle (1) and a third surrounding motor vehicle (7) preceding said first motor vehicle (1) on said at least one first lane (21) of circulation, the setpoint speed generated being defined so that the second distance measured is greater than a second distance of predefined security.

[Claim 5] System according to any one of the preceding claims, characterized in that the first sensor is an image sensor configured to detect a change in the maximum authorized speed signaled by a road sign.

[Claim 6] System according to any one of Claims 1 to 4, characterized in that the first sensor comprises a vehicle communication module configured to receive information relating to a change in the maximum authorized speed.

[Claim 7] System according to the preceding claim, characterized in that the information received includes the first maximum authorized speed (VI), the second maximum authorized speed (V2), location data of said position (25).

[Claim 8] System according to any one of Claims 1 to 4, characterized in that the first sensor comprises a geolocation and navigation module.

[Claim 9] System according to any one of the preceding claims, characterized in that it further comprises a first actuator (12a) capable of acting on the speed of the motor vehicle (1) to reach the setpoint speed generated by the computer (11).

[Claim 10] Motor vehicle (1) comprising the autonomous driving system (10) of any one of the preceding claims.