FR3041778A1 - MOTOR VEHICLE RECOVERY ASSISTING METHOD - Google Patents

Abstract

The present invention relates to a method of assisting the recovery of a vehicle with an automated driving assistance system providing a first fully autonomous driving mode disengaged to the manual driving mode at the end of a first transition phase, and a second completely self-driving mode with disengagement to the manual driving mode at the end of a second transition phase longer than said first transition phase; said method comprising a step of issuing a first alert (400) asking the driver to reposition his hands by precaution on the steering wheel of the vehicle, this step being implemented when said first autonomous driving mode is activated, and in case detection of a risk of a subsequent deterioration of the driving context large enough to cause the disengagement of this first mode of driving.

Description

Title of the invention

Method of assisting the recovery of a motor vehicle.

Field of the invention

The present invention relates to the field of driver assistance systems for motor vehicles.

Background of the invention

Driver assistance systems are now widely used in recent motor vehicles and are undergoing a short development.

Adaptive Cruise Control, better known by the acronym ACC (for "Adaptive Cruise Control" or "Autonomous Cruise Control"), is known, for example. Such a mode of assistance automatically adjusts the speed to maintain a constant safety interval with the vehicle preceding the user from the information collected on this vehicle (including distance and approach speed) using one or more sensors of the radar, lidar or infrared type.

Also known, in particular from the US patent application US 2013/0096767, dynamic systems anti-franking involuntary line. These are commonly referred to as ALKA (for Active Lane Keep Assist), LKAS (for Lane Keep Assistance System), ALA (for Active Lane Assist) or ALC (for Active Lane Control). lines of markings on the ground using sensors and / or optical cameras, and intervene dynamically on the vehicle when the latter deviates from its lane. In such a case, the driver assistance system will then automatically correct the direction of the vehicle and / or activate the braking.

Recently, fully autonomous driving assistance modes have begun to appear in order to relieve the driver in situations of heavy traffic on divided highways where the speed of the vehicle is reduced.

This is particularly the case of assistance modes for driving in traffic jams (better known by the acronym TJC for "Traffic Jam Driver") intended to offload the driver in situations of heavy traffic or traffic jam (speed below 50 / 70 km / h) on divided highways (motorways and short tracks).

In this type of mode, the fully automated guidance can be maintained over a transition period of at least 5 seconds after a degradation of the driving context no longer allowing the continuation of this mode (disengagement with long transition).

There may also be mentioned assistance modes for driving on motorways commonly referred to as HAD (for "Highway Automated Driving") or AHDA (for "Automatic Highway Driving Assist") and able to offload the driver in traffic situations fluid (speed close to the regulatory limit) on separated highways.

In this other type of mode, the fully automated guidance can only be maintained for a short period of 1 to 3 seconds in case of degradation of the driving context no longer allowing this mode to continue (disengagement with short transition).

The driver may then have to take the manual control of the vehicle abruptly and without necessarily being prepared, which may cause inappropriate reflex reactions (such as for example a violent braking or a sudden change of direction) that may be revealed particularly dangerous and accidentogenic.

Object and summary of the invention

The present invention therefore aims to ensure a quieter recovery of the vehicle by the driver in case of abrupt end of an automated driving phase.

It proposes for this purpose a method of assisting the recovery of a motor vehicle with an automated driving assistance system providing a first fully autonomous driving mode to disengage, in case of non-compatibility of the context driving with the continuation of this first autonomous mode, towards the manual driving mode at the end of a first transition phase, and a second fully autonomous driving mode with disengagement, in case of incompatibility of the driving context with the continuation from this second autonomous mode, to the manual driving mode at the end of a second transition phase longer than said first transition phase; said method comprising a step of issuing a first alert asking the driver to reposition his hands on the steering wheel of the vehicle by precaution, this step being implemented when said first autonomous driving mode is activated and in case of detection of a risk of a further degradation of the driving context sufficiently consequent to cause the disengagement of this first mode of driving.

By anticipating a possible disengagement of the first autonomous driving mode having the shortest transition phase, the method according to the invention makes it possible to propose upstream to the driver to reposition as a precaution his hands on the steering wheel, so that the latter is ready if necessary resume manual operation of the vehicle.

According to preferred features of the invention, taken alone or in combination: the existence of such a risk is associated with the occurrence of at least one of the following events: loss of one of the two lines delimiting the the road on which the vehicle is traveling, the beginning of rain, the detection of a next section with a greater sinuosity, or even a future zone of work; said first alert consists in displaying a first visual message on a screen of the vehicle integrated in the instrument cluster, this message being associated with a color code corresponding to an intermediate alert level; - The transmission of said first alert continues until the detection of recovery in the hands of the steering wheel by the driver, or when the risk disappears; said method comprises a step of transmitting a second alert requesting the driver to take back control of the steering wheel, this second alert being issued when said second autonomous driving mode is activated, and in case of non-compatibility of the current driving context. with the continuation of this second mode of driving; said second alert comprises the display on a screen of the vehicle integrated in the instrument cluster of a second visual message associated with an evolutive color code as one approaches the end of said second transition phase ; said second alert also comprises the emission of a series of spaced apart sound signals spaced from one another and whose intensity and / or transmission frequency gradually increases as the term is approaching. said second transition phase; - The emission of said second alert continues until the detection of recovery in hand of the steering wheel by the driver; - Said detection of the recovery in hand of the wheel by the driver causes the deactivation of said second fully autonomous driving mode before the end of said second transition phase, said system then managing only the longitudinal movement of said vehicle; and / or - the return to the manual driving mode can also be initiated by the support of the driver on a deactivation button of the autonomous driving mode activated, the deactivation of this autonomous driving mode intervening only after the detection the presence of the driver's hands on the steering wheel.

Brief description of the drawings The description of the invention will now be continued by the detailed description of an exemplary embodiment, given below by way of illustration but without limitation, with reference to the appended drawings, in which: FIG. a functional diagram of an automated driving assistance system for a motor vehicle; and FIG. 2 is a flowchart of the method according to the invention for assisting the recovery of a vehicle at the end of a completely autonomous driving phase.

Detailed description of a preferred embodiment

With reference to FIG. 1, the automated driving assistance system 1 comprises a driver monitoring module 10, a driving context evaluation module 20, a driving unit 30, an operating mode module. driving assistance 40, as well as an information and warning module 50.

The driver monitoring module 10 comprises a device for detecting the presence of hands on the steering wheel with a capacitive layer implanted between the internal foam padding and the outer casing made of fabric or leather.

The disturbance of the electric field caused by the presence of the hands on the steering wheel causes a variation of the capacity of this sheet.

This detection can also be achieved by other means and in particular by means of pressure sensors located inside the steering wheel and able to measure the local pressure variation occurring when the driver positions his hands on the steering wheel or removes them .

The driving context evaluation module 20 comprises at least one CCD camera (for "Load Coupling Sensors") oriented towards the front of the vehicle and delivering images making it possible to determine the type of road taken (highway, short track or secondary road) based on certain characteristic parameters such as track width, ground marking (color, width and line spacing) and the possible presence of a barrier or a median separation between the two directions of circulation. The analysis of the images provided by this camera also makes it possible to establish the level of fluidity of the road traffic.

The module 20 also comprises a rain detector equipped with an optical or capacitive type sensor integrated for example in the upper part of the windshield, as well as a map of the road network providing a certain number of information on the next sections. encountered by the vehicle (type of road, number of lanes, degree of sinuosity, speed limits, etc ...).

The data collected by the two driver monitoring modules 10 and driving context evaluation 20 are routed in real time to the control unit 30 to which these two modules are connected. The control unit 30, preferably constituted by the intelligent service housing (BSI) of the vehicle, comprises a computer 31 and a storage module 32 comprising non-volatile memory type EEPROM or FLASH and RAM .

This non-volatile memory stores in particular the method according to the invention in the form of a program comprising control lines and intended to be implemented by this computer. The control unit 30 is connected to the actuation module 40 to which it is able to transmit the command to activate or deactivate one of the modes of assistance to driving.

This actuation module 40 comprises a plurality of actuators able to control certain vehicle components such as steering, acceleration, braking and gearbox to ensure the implementation of the various modes of assistance to driving. proposed by the system 1.

In the present case, the latter proposes two completely autonomous modes of driving in which the longitudinal displacement and the lateral displacement of the vehicle are entirely managed in an automated manner.

The first autonomous mode, here HAD type (assistance to driving on the motorway), is intended to fully offload the driver in situations of fluid traffic (speed close to the regulatory limit) on roads with separate roads.

In this first autonomous mode and in case of non-compatibility of the driving context with the continuation of this mode, the disengagement towards the manual driving mode occurs at the end of a first so-called "short" transition phase whose duration is preferentially less than or equal to 3 seconds.

The second autonomous mode, here TJC type (assistance driving in traffic jam), is intended to completely unload the driver in situations of heavy traffic or traffic jam (speed below 50/70 km / h) on roads with pavements separated (motorways and short tracks).

In this second autonomous mode and in case of non-compatibility of the driving context with the continuation of this mode, the disengagement towards the manual driving mode occurs at the end of a second phase of transition longer than the first phase of transition associated in the first autonomous mode and whose duration is preferably greater than or equal to 5 seconds.

The information and warning module 50 comprises a first information display 51 integrated preferably in the instrument cluster of the vehicle and able to broadcast visual messages to the driver, especially when the latter must take back the steering wheel .

The module 50 optionally comprises a second screen 52 integrated in the central console of the dashboard of the vehicle (the latter being preferably constituted by the display screen of the infotainment device) and intended to display visual messages. additional information (indication of the mode of assistance activated as well as driving tasks of which the driver is relieved and those possibly remaining at his expense).

This module 50 is also provided with a siren 53 adapted to emit an acoustic warning signal when the driver must take control of the steering wheel.

We will now describe in detail and in support of the flowchart in Figure 2, the different stages of this process.

This is initiated when the driving of the vehicle is provided autonomously by the system (initial step 100).

The process begins with checking which of the two modes is currently enabled (step 200). If it is the first autonomous mode of HAD type with "short" transition phase, the process continues with step 300 in which the control unit 30 checks, according to the signals received by the module 20, if there is a risk of a subsequent degradation of the driving context sufficiently large to cause the disengagement of this autonomous driving mode and lead to a return with a "short" transition to the manual driving mode (such a degradation of the driving context intervening in case of occurrence of at least one of the following events: simultaneous loss by the camera of the two lines delimiting the path on which the vehicle is traveling, rain, too steep curve or passage to a single traffic lane due to works). The control unit 30 will detect the existence of such a risk in the event of occurrence of at least one of the following events: the loss by the camera of one of the two lines delimiting the path on which the vehicle is traveling. , a beginning of rain, the detection of a next section with a sharper sinuosity or even that of an upcoming area of work.

In the absence of risk, the process repeats this step 300 after a time interval between 100 and 500 ms and preferably equal to 200 ms.

When a risk is detected, the system then means to the warning module 50 to issue an alert to the driver to indicate that risk and ask him to reposition his hands by hand on the steering wheel (step 400).

This alert will include a visual component resulting for example in the display of a visual message displayed on the first information screen 51 and associated with a color code corresponding to an intermediate alert level (typically orange). The alert stops (step 500) when the module 10 detects the recovery in hand of the steering wheel by the driver or when the risk disappears (event 450).

In case of recovery in the hands of the steering wheel, the autonomous driving mode nevertheless continues to remain active until the driving context degrades sufficiently to cause the disengagement of this mode with a "short" transition phase to the driving mode manual.

We will now return to step 200 of the process according to the invention, during which the process verifies which of the two fully autonomous driving modes is currently activated. If it is the second type of TJC disengaged mode with "long" transition, the process continues with step 600 in which it estimates based on the signals received by the module 20 if current driving context is consistent with the continuation of this autonomous driving mode.

If so, the process repeats this step 600 after a time interval of between 100 and 500 ms and preferably 200 ms.

If not, the system then means to the warning module 50 to issue an alert to the driver to signal the end of the next self-driving mode and ask him to resume control of the steering wheel (step 700).

This alert will include a visual component resulting for example in the display of a visual message (such as that shown in Figure 3) displayed on the first information screen 51 and associated with an evolving color code as and when as you get closer to the end of the second transition phase (for example green, then orange, then finally red). The alert may also include a sound component consisting for example in the emission of a series of spaced apart sound signals spaced from each other and whose intensity and / or transmission frequency increase gradually as and when we are nearing the end of the second transition phase. The alert stops (step 800) when the module 10 detects the recovery by hand of the steering wheel by the driver (event 750).

After this recovery in the hands of the steering wheel, the process displays a countdown of seconds remaining before returning to manual driving mode on the second screen 52 integrated in the center console of the dashboard of the vehicle. The automated driving assistance system 1 deactivates the fully autonomous driving mode before the end of the second transition phase (typically: 2 or 3 seconds before) and only manages the longitudinal movement of the vehicle keeping the same instruction of speed.

If the driver has still not taken over the steering wheel shortly before the second transition phase comes to an end (for example, 2 or 3 seconds ago), the system operates a deceleration of the vehicle intended to react driver.

According to an alternative embodiment not shown, the return to the manual driving mode can also be requested by the driver support on a deactivation button of the autonomous driving mode enabled.

In such a case, the deactivation of this autonomous driving mode intervenes only when the process detects the presence of the driver's hands on the steering wheel.

In the meantime, a visual message asking the driver to put his hands on the steering wheel to confirm the transition to manual driving will be displayed on the first information screen 51 and associated with a color code corresponding to a lack of danger ( typically green). In general, it is recalled that the present invention is not limited to the embodiments described and shown, but encompasses any embodiment within the scope of those skilled in the art.

In particular, the number, the characteristics as well as the fields of application of the modes of assistance to driving can be substantially different from the embodiment described previously.

Claims (10)

1. A method of assisting the recovery of a motor vehicle with an automated driving assistance system (1) providing a first fully autonomous driving mode to disengage, in case of incompatibility of the context of driving with the continuation of this first autonomous mode, towards the manual driving mode at the end of a first transition phase, and a second fully autonomous driving mode with disengagement, in case of non-compatibility of the driving context with the continuation of this second autonomous mode, to the manual driving mode at the end of a second transition phase longer than said first transition phase; said method comprising a step of issuing a first alert (400) requesting the driver to reposition his hands on the vehicle steering wheel by precaution, this step (400) being implemented when said first autonomous driving mode is activated and in case of detection of a risk of a subsequent deterioration of the driving context large enough to cause the disengagement of this first mode of driving. 2. A method of assisting the recovery of a motor vehicle according to claim 1, characterized in that the existence of such a risk is associated with the occurrence of at least one of the following events: loss one of the two lines delimiting the path on which the vehicle is traveling, the beginning of rain, the detection of a next section with a sharper sinuosity or even of an upcoming zone of work. 3. A method of assisting the recovery of a motor vehicle according to one of claims 1 or 2, characterized in that said first alert consists of the display of a first visual message on a screen of the integrated vehicle in the instrument cluster, this message being associated with a color code corresponding to an intermediate alert level. 4. A method of assisting the recovery of a motor vehicle according to one of claims 1 to 3, characterized in that the emission of said first alert (400) continues until the detection of recovery in the hands of the steering wheel by the driver, or when the risk disappears (410). 5. A method of assisting the recovery of a motor vehicle according to one of claims 1 to 4, characterized in that it comprises a step of issuing a second alert (700) asking the driver to resume driving the hand, this second alert being issued when said second autonomous driving mode is activated, and in case of non-compatibility of the current driving context with the continuation of this second driving mode. 6. A method of assisting the recovery of a motor vehicle according to claim 5, characterized in that said second alert comprises the display on a screen of the vehicle integrated in the instrument cluster of a second visual message associated to an evolutive color code as we approach the end of said second transition phase. 7. A method of assisting the recovery of a motor vehicle according to claim 6, characterized in that said second alert also comprises the emission of a series of spaced apart sound signals spaced from each other and whose intensity and / or the transmission frequency increase progressively as one approaches the end of said second transition phase. 8. A method of assisting the recovery of a motor vehicle according to one of claims 5 to 7, characterized in that the emission of said second alert (700) continues until the detection of recovery in the hands of the steering wheel by the driver (750). 9. A method of assisting the recovery of a motor vehicle according to claim 8, characterized in that said detection of the recovery in hand of the steering wheel by the driver causes the deactivation of said second fully autonomous driving mode before the term of said second transition phase, said system then managing only the longitudinal displacement of said vehicle. 10. A method of assisting the recovery of a motor vehicle according to one of claims 1 to 9, characterized in that the return to the manual driving mode can also be initiated by the driver support on a deactivation button of the autonomous driving mode activated, the deactivation of this autonomous driving mode intervening only after detection the presence of the hands of the driver on the steering wheel.