Method for safely and autonomously performing an emergency stop on a vehicle

Abstract

One aspect of the invention relates to a method for safely and autonomously performing an emergency stop on a vehicle (200) travelling in a lane, and comprising the following steps: - Detecting (101) an inability of a driver to drive the vehicle (200); - Activating (102) an emergency stop assistance function implemented on the vehicle (200), causing the following steps to be implemented: o At least one driver alerting step (1021, 1022); o If the driver, during the alerting step (1021, 1022), fails to meet a condition indicating that they have regained control, a step (1023) of decelerating the vehicle (200) until it is stopped; a function of controlling the positioning of the vehicle (200) in the lane, implemented on the vehicle (200), effecting a progressive moving of the vehicle (200) towards a line (201) defining the lane, during the alerting step (1021, 1022) and the deceleration step (1023).

Description

DESCRIPTION TITLE: Safe, autonomous emergency stopping procedure for a vehicle TECHNICAL FIELD OF THE INVENTION

[0001] The technical field of the invention is that of safety functions in vehicles, and more particularly that of emergency stopping functions in vehicles.

[0002] The present invention relates to a method for the emergency stopping of a vehicle, and in particular to a safe, autonomous emergency stopping method for a vehicle. The invention also relates to a vehicle and a computer program for implementing the method. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0003] The emergency stop assist function or Risk Mitigation Function (RMF) is a feature that allows the driver, in the event of hands being released from the steering wheel, drowsiness or distraction for a certain period of time, to automatically stop the vehicle in its lane after a certain number of alerts and over a period that can extend over more than 30 seconds.

[0004] This function is specifically designed to make the vehicle safe if the driver experiences, for example, a medical emergency.

[0005] The current problem with this function is that the vehicle is stopped in the middle of the lane in which it is traveling, which can create dangerous situations, for example in the case where another vehicle comes from behind the vehicle at high speed and wants to avoid the stopped vehicle.

[0006] There is therefore a need for a process enabling an autonomous emergency stop of a vehicle when its driver is unable to drive, which limits the risks for the driver and other road users. SUMMARY OF THE INVENTION

[0007] The invention offers a solution to the problems mentioned above, by allowing the autonomous emergency stopping of the vehicle without endangering the driver or other road users.

[0008] A first aspect of the invention relates to a safe, autonomous emergency stopping method for a vehicle traveling on a road, comprising the following steps: Detection of a driver's inability to drive the vehicle; Activation of an emergency stop assistance function implemented on the vehicle, resulting in the implementation of the following steps: o At least one driver alert step; o In the absence of implementation of a driver takeover condition during the alert step, a vehicle deceleration step until it comes to a stop; a vehicle positioning control function implemented on the vehicle, implementing a progressive shift of the vehicle towards a lane boundary line, during the alert step and the deceleration step.

[0009] Thanks to the invention, a vehicle positioning control function within the lane is activated during the vehicle's autonomous emergency stop, and the vehicle is progressively shifted to one side of the lane to facilitate overtaking by other vehicles approaching from behind during and after the vehicle's stop. This reduces the risk of collision.

[0010] In addition to the characteristics mentioned in the preceding paragraph, the process according to the invention may have one or more additional characteristics from among the following, considered individually or according to all technically possible combinations.

[0011] According to one embodiment, as long as the vehicle speed is greater than or equal to a threshold or as long as the deceleration step has not started, the distance between the line and the vehicle during the implementation of the offset is reduced linearly along a first slope as a function of the vehicle speed.

[0012] According to a sub-embodiment of the preceding embodiment, as soon as the vehicle speed is below said threshold or the deceleration phase has begun, and if the vehicle is in a curve when the offset is implemented, the distance between the line and the vehicle during the implementation of the offset is reduced linearly along a second slope as a function of the vehicle speed, to reach a first distance, the second slope being greater than the first slope.

[0013] According to an alternative embodiment of the previous sub-variant embodiment, as soon as the vehicle speed is below said threshold or the deceleration step has begun, and if the vehicle is in a straight line when the offset is implemented, the distance between the line and the vehicle is decreased linearly as a function of the vehicle speed along a third slope to reach a second distance, the third slope being greater than the second slope, the second distance being less than the first distance.

[0014] Thus, the distance between the lane marking and the stationary vehicle is reduced more rapidly as soon as the vehicle's speed is sufficiently low, making it easier for other vehicles to perform evasive maneuvers. When the vehicle is on a curve, the safety margin from the lane marking is reduced, but less so than when the vehicle is traveling straight, in order to avoid putting the driver at greater risk on the curve.

[0015] According to an embodiment compatible with the previous embodiment, the method according to the invention includes a step of reducing a sensitivity threshold of a line crossing alert function.

[0016] Thus, reducing the sensitivity threshold of the line crossing alert function makes it possible to reduce the safety margin with respect to the line delimiting the track.

[0017] According to an embodiment compatible with previous embodiments, the vehicle positioning control function in the lane is activated if a lane following function is activated.

[0018] According to an embodiment compatible with previous embodiments, activation of the emergency stop assist function results in the implementation of a vehicle holding stationary step.

[0019] According to an embodiment compatible with the previous embodiments, the process according to the invention comprises a first step an alert and a second alert stage, an audible and / or visual signal being emitted during the first alert stage and the second alert stage and at least one vehicle speed or trajectory control function is implemented, and / or the brakes are activated, during the second alert stage.

[0020] A second aspect of the invention relates to a vehicle comprising means for implementing the process according to the invention.

[0021] A third aspect of the invention relates to a computer program product comprising instructions which, when the program is executed by a computer, lead the computer to implement the steps of the process according to the invention.

[0022] The invention and its various applications will be better understood by reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES

[0023] The figures are presented for illustrative purposes only and are in no way limiting to the invention. Figure 1 is a synoptic diagram illustrating the sequence of steps of a process according to the invention. Figure 2 shows a schematic representation of a vehicle on which the process according to the invention is applied, as a function of time. Function 3 is a graph representing the distance between the vehicle and a line delimiting the lane in which the vehicle is traveling, as a function of the vehicle's speed. DETAILED DESCRIPTION

[0024] Unless otherwise specified, the same element appearing on different figures has a unique reference.

[0025] The invention relates to a method for the emergency stopping of a vehicle autonomously, that is to say without intervention from a driver of the vehicle.

[0026] The sequence of steps in process 100 is illustrated in Figure 1 and their effects on vehicle 200 as a function of time are illustrated in Figure 2.

[0027] Vehicle 200 is travelling on a lane delimited by an outer line 201.

[0028] A first step 101 of process 100 is to detect an inability of the driver to drive the vehicle 200, for example following a medical emergency of the driver.

[0029] Such an incapacity is detected, for example, if the driver's hands are taken off the steering wheel, or if drowsiness or distraction is detected for a certain period of time. The detection of drowsiness or distraction is achieved, for instance, using a camera and artificial intelligence trained to identify certain signs in the driver, such as closed eyes, from images acquired by the camera.

[0030] In figure 2, the detection of the driver's incapacity is carried out at time tO and the vehicle 200 then has a speed vO.

[0031] A second step 102 of process 100 consists of activating an emergency stop assist function implemented on the vehicle 200 or Risk Mitigation Function (RMF) in English.

[0032] Such activation is performed automatically.

[0033] In figure 2, the second step 102 is implemented at time t1 and the vehicle then has a speed v1.

[0034] Activating the emergency stop assist function triggers the following steps of procedure 100.

[0035] At least one driver alert step 1021, 1022 is implemented following activation of the emergency stop assist function.

[0036] The 1021, 1022 alert step consists, for example, of emitting an audible and / or visual signal to the driver and / or implementing at least one vehicle speed or trajectory control function 200 and / or activating the brakes.

[0037] The emission of a visual signal consists, for example, of displaying a message on a screen of vehicle 200, the message being, for example, "Emergency stop Take back control".

[0038] The speed control function is, for example, a speed regulation function.

[0039] The trajectory control function is, for example, a lane-keeping assistance function.

[0040] According to an alternative implementation, a first alert step 1021 and a second alert step 1022 are implemented following the activation of the emergency stop assistance function.

[0041] In Figure 2, the first step 1021 is implemented between times t1 and t2 and the second step 1022 is implemented between times t2 and t3.

[0042] The first alert step 1021 consists, for example, of implementing the speed control function and the lane keeping assist function, and the second alert step 1022 consists, for example, of implementing the speed control function, the lane keeping assist function and activating the brakes in the form of jerks.

[0043] If the driver does not implement a takeover condition during the alert step(s) 1021, 1022, a slowdown step 1023 of vehicle 200 is carried out.

[0044] A condition for regaining control is, for example, a change in position of the brake pedal and / or the accelerator pedal, and / or a torque action on the steering wheel, and / or the detection of hands on the steering wheel and / or the activation of a cancel button.

[0045] Step 1023 of the deceleration procedure consists of slowing down vehicle 200 until vehicle 200 comes to a stop, by applying a deceleration instruction to vehicle 200.

[0046] In Figure 2, the deceleration step 1023 is implemented between times t3 and t4 and the vehicle 200 goes from a non-zero speed v3 to a zero speed v4.

[0047] The deceleration setpoint is, for example, between 0 and 1 m / s 2

[0048] During the alert stage 1021, 1022 and the slowdown stage 1023, a lane positioning control function for vehicle 200 implemented on vehicle 200 is activated.

[0049] Such activation is performed automatically.

[0050] The vehicle positioning control function 200 in the lane is, for example, a function that allows the vehicle, when the lane following assistance function is activated, to automatically move to one side of the lane to allow, for example, motorcycles to pass between lanes, or to move away from a truck that is being overtaken.

[0051] Activating the vehicle positioning control function for vehicle 200 in the lane allows for the implementation of a progressive shift of vehicle 200 towards line 201 delimiting the traffic lane.

[0052] In Figure 2, the distance between vehicle 200 and line 201 gradually decreases between times t1 and t4.

[0053] Figure 3 shows the evolution of the distance d between vehicle 200 and line 201, as a function of the speed v of vehicle 200, during the implementation of the shift.

[0054] As long as the speed v of vehicle 200 is greater than or equal to a threshold or as long as the slowdown step 1023 has not started, i.e. as long as the alert step 1021, 1022 is in progress, the distance d between line 201 and vehicle 200 is reduced linearly along a first slope p1 as a function of the speed v of vehicle 200.

[0055] The threshold is, for example, 30 km / h.

[0056] As soon as the speed v of vehicle 200 is below said threshold or as soon as the deceleration step 1023 has started, if vehicle 200 is in a turn when the shift is implemented, the distance d between line 201 and vehicle 200 is reduced linearly along a second slope p2 as a function of the speed v of vehicle 200, to reach a first distance d1.

[0057] The second slope p2 is, for example, greater than the first slope p1.

[0058] The first distance d1 is, for example, 30 cm.

[0059] As soon as the speed v of vehicle 200 is below said threshold or as soon as the deceleration step 1023 has begun, if vehicle 200 is in a straight line when the shift is implemented, the distance d between line 201 and vehicle 200 is reduced linearly as a function of the speed v of vehicle 200 according to a third slope p3, to reach a second distance d2.

[0060] The third slope p3 is, for example, greater than the second slope p2.

[0061] The second distance d2 is, for example, less than the first distance d1.

[0062] The second distance d2 is, for example, 0 cm.

[0063] In Figure 3, the distance d between line 201 and vehicle 200 is decreased linearly along the first slope p1 between times t1 and t3, i.e. during the alert stage 1021, 1022, then depending on whether vehicle 200 is in a turn or in a straight line when the shift is implemented, the distance d between line 201 and vehicle 200 is decreased linearly along the second slope p2 in solid lines, respectively the third slope p3 in dashed lines, between times t3 and t-4, i.e. during the deceleration stage 1023.

[0064] The method 100 according to the invention may include a step of reducing a sensitivity threshold of a line crossing warning function.

[0065] The sensitivity threshold, for example, goes from 0 cm to -30 cm.

[0066] A step 1025 of holding vehicle 200 in place is carried out once vehicle 200 has stopped.

[0067] An audible and / or visual signal may also be emitted during the 1025 standstill step.

[0068] The emission of a visual signal consists, for example, of displaying a message on a screen of vehicle 200, the message being, for example, "Emergency stop carried out".

Claims

DEMANDS 1. A method (100) for the safe, autonomous emergency stopping of a vehicle (200) travelling on a lane, comprising the following steps: - Detection (101) of a driver's inability to drive the vehicle (200); - Activation (102) of an emergency stop assistance function implemented on the vehicle (200), resulting in the implementation of the following steps: o At least one driver alert step (1021, 1022); o In the absence of implementation of a driver takeover condition during the alert step (1021, 1022), a slowing-down step (1023) of the vehicle (200) until it comes to a stop; the method (100) being characterized in that a vehicle (200) positioning control function implemented on the vehicle (200) implements a progressive shift of the vehicle (200) towards a line (201) delimiting the lane, during the alert step (1021, 1022) and the slowing-down step (1023).

2. Method (100) according to the preceding claim, wherein, as long as the speed (v) of the vehicle (200) is greater than or equal to a threshold or as long as the deceleration step (1023) has not started, the distance (d) between the line (201) and the vehicle (200) during the implementation of the offset is decreased linearly along a first slope (p1) as a function of the speed (v) of the vehicle (200).

3. Method (100) according to the preceding claim, wherein, as soon as the speed (v) of the vehicle (200) is below said threshold or the deceleration step (1023) has begun, and if the vehicle (200) is in a turn when the offset is implemented, the distance (d) between the line (201) and the vehicle (200) during the implementation of the offset is decreased linearly along a second slope (p2) as a function of the speed (v) of the vehicle (200), to reach a first distance (d1), the second slope (p2) being greater than the first slope (p1).

4. Method (100) according to the preceding claim, wherein as soon as the speed (v) of the vehicle (200) is below said threshold or the deceleration step (1023) has begun, and if the vehicle (200) is in a straight line when the shift is implemented, the distance (d) between the line (201) and the vehicle (200) is decreased linearly as a function of the speed (v) of the vehicle (200) along a third slope (p3) to reach a second distance (d2), the third slope (p3) being greater than the second slope (p2), the second distance (d2) being less than the first distance (d1).

5. Method (100) according to any one of the preceding claims, comprising a step (1024) of reducing a sensitivity threshold of a line crossing warning function.

6. Method (100) according to any one of the preceding claims, wherein the vehicle positioning control function in the lane is activated if a lane following function is activated.

7. Method (100) according to any one of the preceding claims, wherein the activation of the emergency stop assist function results in the implementation of a step (1025) of holding the vehicle (200) stationary.

8. Method (100) according to any one of the preceding claims, comprising a first warning stage (1021) and a second warning stage (1022), an audible and / or visual signal being emitted during the first warning stage (1021) and the second warning stage (1022) and at least one vehicle speed or trajectory control function (200) is implemented, and / or the brakes are activated, during the second warning stage (1022).

9. Vehicle (200) comprising means for implementing the method (100) according to any one of the preceding claims.

10. A computer program is a product comprising instructions which, when the program is executed by a computer, cause the computer to put into operation works the steps of the process (100) according to any one of the claims 1 to 8.

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