WO2022074307A1

WO2022074307A1 - Method and device for autonomous driving of a vehicle in order to keep the vehicle at the centre of a traffic lane

Info

Publication number: WO2022074307A1
Application number: PCT/FR2021/051518
Authority: WO
Inventors: David Giraud; Matthieu VARNIER
Original assignee: Psa Automobiles Sa
Priority date: 2020-10-07
Filing date: 2021-09-03
Publication date: 2022-04-14
Also published as: FR3114787A1

Abstract

The invention relates to a method and a device for autonomous driving of a vehicle in order to keep the vehicle at the centre of a traffic lane. The method comprises the steps of: - receiving a lane positioning instruction from the driver of the vehicle; - keeping the vehicle in the lane according to the positioning instruction. The method is characterised in that it further comprises the steps of: - determining a path to reach the centre of the lane; - triggering a time delay, and, at the end of the time delay, guiding the vehicle along the path such that the vehicle reaches the centre of the lane.

Description

DESCRIPTION

Title: Method and device for autonomous driving of a vehicle in order to keep the vehicle in the center of a traffic lane.

The present invention claims the priority of French application 2010233 filed on 07.10.2020, the content of which (text, drawings and claims) is incorporated herein by reference. The invention relates to autonomous driving vehicles, and more specifically to assistance devices which are intended to help the drivers of such vehicles to drive them.

“Vehicle” means any type of vehicle such as a motor vehicle, moped, motorcycle, warehouse storage robot, etc. “Autonomous driving” of an “autonomous vehicle” means any process capable of assisting the driving of the vehicle. The method can thus consist in partially or totally directing the vehicle or providing any type of assistance to a natural person driving the vehicle. The process thus covers all autonomous driving, from level 0 to level 5 in the OICA scale, for Organization International des Constructeurs Automobiles.

The document FR3070031 describes a method and device for assisting the automated driving of a vehicle, with control of the transverse positioning by action of the driver in order to provide natural lane maintenance for the driver. Autonomous driving guides the vehicle laterally in the lane according to the positioning instruction, a chosen distance, coming from the driver of the vehicle. The distance chosen is a distance other than that corresponding to the center of the track. The vehicle is automatically driven to stay in this lateral position without returning to the center of the lane.

However, this solution is not compatible with certain regulations requiring the vehicle to remain in the center of its lane.

An object of the present invention is to remedy the aforementioned problem, in particular to provide lane maintenance compatible with the regulations but also allowing adjustment by the user. To this end, a first aspect of the invention relates to a method for autonomous driving of a vehicle in order to keep the vehicle in the center of a traffic lane. Said method comprises the steps of:

- reception of a positioning instruction in the lane, coming from the driver of the vehicle;

- maintains said vehicle in the lane according to the positioning instruction.

The method being characterized in that it further comprises the steps of:

- determination of a trajectory to reach the center of the track;

- triggering a time delay, and, at the end of the time delay, guiding said vehicle along the trajectory so that said vehicle reaches the center of the lane.

Thus, the driver can position the vehicle laterally at a distance other than that of the center of the lane. The vehicle is temporarily held in the set position desired by the driver while being guided so that the vehicle reaches the center of the lane, which makes it compatible with regulations imposing such behavior. Autonomous driving to keep the vehicle in the center of the lane is not deactivated.

Advantageously, the time delay is reset on receipt of a new positioning instruction in the lane from the driver.

Thus, for each new position desired by the driver, the duration of the temporary holding in the set position desired by the driver is constant.

Advantageously, guidance is interrupted upon receipt of a new positioning instruction in the lane from the driver.

Thus, naturally, the driver redefines a target position without waiting for the vehicle to first reach the center of the lane.

According to the preferred mode of operation, the delay is between 5 and 30 seconds. Of course, this time delay can take on any other value in another operating mode. Advantageously, the delay is a function of the traffic conditions on said lane and/or of the speed of said vehicle.

A vehicle with lane centering autonomous driving has environmental perception devices (camera, radar, lidar, ultrasound, or other range finders). These organs enable them to determine traffic conditions. By traffic condition is meant, for example, the determination of heavy traffic on the lane, the presence of trucks and their locations on the lane, the presence of two wheels and their locations on the lane, .. For example, in the presence of numerous two-wheelers in the inter-lanes, the time delay is longer than when there are no two-wheelers in the inter-lanes. This makes it possible to maintain the offset, the positioning instruction in the lane, longer with respect to the center of the lane desired by the driver to let the two wheels pass. In heavy traffic, an automatic lane change is not recommended. It is then not necessary to quickly reach the center of the track.

Furthermore, it may be useful to take the speed of the vehicle into account in order to modulate the delay. For example, having a time delay inversely proportional to the speed of the vehicle ensures that the return to the center of the lane takes place over a given distance, and no longer over a given duration.

Advantageously, the trajectory to reach the center of the lane is determined so that the vehicle reaches the center of the lane within a predetermined time. Thus, the driver easily understands that the autonomous driving of maintaining the center of the lane is indeed active. In an operation mode, the predetermined time is of the order of 5 to 15 seconds. Thus the automatic return of the vehicle to the center of the lane is not too fast, which can give the users of the vehicle an impression of instability of autonomous driving. The automatic return to the center of the lane is neither too slow, which can give vehicle users the impression that the function is absent or that the vehicle is drifting slowly, synonymous with poor suspension adjustment.

Advantageously, the predetermined time is a function of the type of lane, of the traffic conditions of said lane and/or of the speed of said vehicle. By type of lane, we mean the different traffic lanes (motorways, national roads, departmental roads, municipal roads, private roads, etc.) and their layouts (number of lanes and their mergers or divisions, crossings, profiles/curves . ..). In one operating mode, the time for the vehicle to reach the center of the lane will be greater on straight portions of road than on portions of roads with numerous curves.

In order to improve safety and understanding by other users of the traffic lane, the time for the vehicle to reach the center of the lane will be determined according to the traffic or the speed of the vehicle.

A second aspect of the invention relates to a device comprising a memory associated with at least one processor configured to implement the method according to the first aspect of the invention.

The invention also relates to a vehicle comprising the device.

The invention also relates to a computer program comprising instructions adapted for the execution of the steps of the method when said program is executed by at least one processor.

Other characteristics and advantages of the invention will emerge from the description of the non-limiting embodiments of the invention below, with reference to the appended figures, in which:

[Fig. 1] schematically illustrates a device, according to a particular embodiment of the present invention.

[Fig. 2] schematically illustrates autonomous driving of a vehicle in order to keep the vehicle in the center of a traffic lane, according to a particular embodiment of the present invention.

The invention is described below in its non-limiting application to the case of an autonomous motor vehicle traveling on a road. Other applications such as a robot in a storage warehouse or a motorcycle on a country road are also possible.

FIG. 1 represents an example of a device 101 included in the vehicle, in a network (“cloud”) or in a server. This device 101 can be used as as a centralized device in charge of at least certain steps of the method described below with reference to FIG. 2. In one embodiment, it corresponds to an autonomous driving computer.

In the present invention, the device 101 is included in the vehicle.

This device 101 can take the form of a box comprising printed circuits, of any type of computer or even of a mobile telephone (“smartphone”).

The device 101 comprises a random access memory 102 for storing instructions for the implementation by a processor 103 of at least one step of the method as described above. The device also comprises a mass memory 104 for storing data intended to be kept after the implementation of the method.

The device 101 may also include a digital signal processor (DSP) 105. This DSP 105 receives data to shape, demodulate and amplify, in a manner known per se, this data.

Device 101 also includes an input interface 106 for receiving data implemented by the method according to the invention and an output interface 107 for transmitting data implemented by the method according to the invention.

FIG. 2 schematically illustrates autonomous driving of a vehicle in order to keep the vehicle in the center of a traffic lane, according to a particular embodiment of the present invention.

Step 201, Rx Pos, is the reception, by the device 101, of a positioning instruction in the lane coming from a driver of the vehicle. In a preferred operating mode, the setpoint setpoint position is determined from measurements of the force on the steering wheel and/or measurements of the angle of rotation of the steering wheel. The transmission of the positioning setpoint is carried out between electrical boxes or computers, for example between those who control a steering system of the vehicle and the device 101 . In one embodiment the device 101 is included in the computers controlling the steering system.

In another embodiment, the determination of the position instruction in the lane coming from the driver and obtained by an interface system Man-Machine, for example a touch screen on a dashboard of the vehicle, which transmits, for example by wire on a CAN network, to the device 101 .

In step 202, Mntn Pos, autonomous driving maintains the vehicle according to the positioning instruction. For example, for a vehicle traveling in the left lane, the vehicle is off-center to the left in the lane, thus leaving more room for two-wheelers in the inter-lane (this is the situation where two-wheelers travel between two lanes and move up the lane faster than other vehicles traveling in these two lanes).

Step 203, Det Traj, determines a trajectory to reach the center of the track from the positioning instruction. This trajectory can be in any form of curve (for example of the straight line, clothoid, polynomial type, etc.), and can come from a classic trajectory planning module.

In one embodiment, this trajectory is determined so that the vehicle reaches the center of the lane in a predetermined time. This predetermined time can be fixed, for example between 5 and 15 seconds.

In another operating mode, this predetermined time depends on the type of channel. For example on expressways, motorways, this time may be longer, close for example to 15 seconds, than on a national road close for example to 5 seconds. In another example, on a motorway in the event of lane splitting, lane merging, this time may be close to 10 seconds.

In another operating mode, this predetermined time depends on the traffic conditions of said lane. In the case of heavy traffic, this time is higher than in the case of light traffic

In another operating mode, this predetermined time is a function of the speed of said vehicle. This function can make it possible to return to the center of the lane over a given distance or over a given maximum distance for high vehicle speeds (for example > 110 km/h).

In step 204, Tempo, a timer is started. It is an action that allows you to delay another launched action. In one mode of operation, a counter configured to represent a duration is defined. Initially, the counter is initialized to zero. At each calculation cycle, no time, the counter is incremented by the time step. When the counter exceeds a threshold configured to represent the duration, the timer is finished. At the end of this delay, autonomous driving guides the vehicle along the trajectory so that the vehicle reaches the center of the lane. In a preferred mode of operation, the delay is between 5 and 30 seconds. Of course, the time delay can take any other value.

In one embodiment, the time delay is reset (to zero) on receipt of a new positioning instruction in the lane from the driver. In another embodiment, guidance is interrupted on receipt of a new positioning instruction in the lane from the driver. The method returns to step 202.

In one operating mode, the time delay is a function of the traffic conditions. The traffic conditions determined conventionally by the organs of perception on board the vehicle (camera, RADAR, LIDAR, ultrasound, or other range finders). Traffic conditions can also be determined from Vehicle-to-Vehicle (V2V), Vehicle-to-infrastructure (V2I), or Vehicle-to-other (V2X) communication. These communications are supported by radio frequency exchanges based on 4G, 5G or other standards.

In one operating mode, in the presence of many two-wheelers in the interlanes, the time delay is longer than when there are no two-wheelers in the interlanes. In one operating mode, the delay is a function of the speed of said vehicle, which makes possible a delay as a function of the distance traveled by the vehicle.

The present invention is not limited to the embodiments described above by way of examples; it extends to other variants.

Thus, an embodiment has been described in which the steps of the method described above with reference to FIG. 2 follow one another in chronological order. The present invention is also applicable for a different chronology of the steps, thus the step 204 can, for example, intervene before the step 203 which makes it possible to determine the trajectory according to the value of the delay.

Claims

1 . Method for autonomous driving of a vehicle in order to keep the vehicle in the center of a traffic lane, said method comprising the steps of:

- reception (201) of a positioning instruction in the lane, coming from the driver of the vehicle;

- maintains (202) said vehicle in the lane according to the positioning instruction; characterized in that the method further comprises the steps of:

- determination (203) of a trajectory to reach the center of the track;

2. Method according to claim 1, in which the timer is reset on receipt of a new positioning instruction in the lane from the driver.

3. Method according to one of claims 1 or 2, wherein the guidance is interrupted upon receipt of a new positioning instruction in the lane from the driver.

4. Method according to one of claims 1 to 3, wherein the delay is between 5 and 30 seconds.

5. Method according to one of claims 1 to 4, wherein the delay is a function of the traffic conditions on said lane and / or the speed of said vehicle.

6. Method according to one of claims 1 to 5, wherein the path (203) to reach the center of the lane is determined so that the vehicle reaches the center of the lane in a predetermined time.

7. Method according to claim 6, in which the predetermined time is a function of the type of lane, the traffic conditions of said lane and/or the speed of said vehicle.

8. Device (101) comprising a memory (102) associated with at least one processor (103) configured to implement the method according to one of claims 1 to 7.

9. Vehicle comprising the device (101) according to claim 8.

10. Computer program comprising instructions adapted for the execution of the steps of the method according to one of claims 1 to 7 when said program is executed by at least one processor (101).