Improved automatic restart after a vehicle is stopped

Abstract

The invention relates to a method for controlling a restart function after a stop implemented by an adaptive cruise control module of a vehicle. The adaptive cruise control module controls the longitudinal speed of the vehicle without manual control by a driver. The method comprises the following steps, while the adaptive cruise control module is activated: - following a stop (201) of the vehicle, verify (202) that at least one descriptive element of a driving situation satisfies at least one predefined restart condition; - if at least one descriptive element satisfies at least one restart condition, verify (203) that the driver of the vehicle is attentive; - if the driver of the vehicle is attentive, automatically restart (204) the vehicle for longitudinal speed control by the adaptive cruise control module. FIG. 2

Description

Title of the invention: Improved automatic restart after a vehicle has stopped

[0001] The present invention belongs to the field of driving assistance functions in a vehicle, in particular a function of an adaptive speed control module, also called ACC for "Adaptive Cruise Control" in English.

[0002] The term “vehicle” means any type of vehicle such as a private, utility or heavy goods vehicle.

[0003] The term "driving assistance" for a vehicle refers to any method capable of assisting the driving of the vehicle. This method may consist of partially or fully steering the vehicle or providing any type of assistance to a person driving the vehicle. Driving assistance functions can relate to different levels of autonomy. The OICA (International Organization of Motor Vehicle Manufacturers) scale notably provides for six levels. Other scales exist to define the levels of autonomy enabled by driving assistance systems, such as the SAE (Society of Automotive Engineers) scale.

[0004] Thus, driving assistance covers functions of assistance to manual driving, for the lowest levels, such as levels 1 and 2 of the aforementioned scales, and autonomous vehicle piloting functions for the highest levels of autonomy.

[0005] Driver assistance systems, such as AD AS for "Advanced Driver-Assistance Systems", allow the driver of the vehicle to be assisted or even to fully control certain parameters of the vehicle's steering, such as longitudinal trajectory, speed in particular, and lateral trajectory, turning or changing lanes in particular.

[0006] These systems make it possible to improve driving comfort as well as safety, by taking advantage of data from vehicle sensors, such as radar or lidar data, cameras and / or geolocation devices.

[0007] Current AD AS systems generally include an ACC system or module, capable of implementing an adaptive speed regulation function, for controlling in particular the longitudinal speed of the vehicle based on information from sensors, for example from camera, radar and / or lidar.

[0008] For levels 2 and 2+, the ACC module may be equipped with an automatic restart function after the vehicle has stopped, which may be a function called "stop and go" in English or a "traffic jam assist" function, such a function allowing, after deceleration of the vehicle by the ACC module until the vehicle comes to a stop, to automatically restart the vehicle without requiring manual intervention from the driver, if descriptive data of the driving situation meet restart conditions.

[0009] In its current implementations, the stop and go function is active for a certain duration after the vehicle has stopped, which is generally equal to a few seconds, for example three seconds.

[0010] However, beyond such a duration, the existing functions are not permitted to automatically restart the vehicle after it has stopped, as it is assumed that the driver is likely to be inattentive. Therefore, beyond such a duration, the driver is required to take an action such as pressing a dedicated button on the vehicle's dashboard or pressing the accelerator pedal.

[0011] Thus, current automatic restart functions after a stop are limited to a short duration, and the resumption of control by the ACC module requires physical action from the driver's hand or foot, which degrades the vehicle user experience. Furthermore, the driver is not informed that the restart conditions are met, which may delay the driver's action to return control to the ACC module and may, in certain situations, pose safety problems.

[0012] There is therefore a need to improve an automatic restart function after the vehicle has stopped, in a safe manner and by improving the user experience of the vehicle.

[0013] The present invention improves the situation.

[0014] To this end, a first aspect of the invention relates to a method for controlling a restart function after stopping, implemented by an adaptive cruise control module of a vehicle, the adaptive cruise control module being capable of controlling a longitudinal speed of the vehicle without manual control by a driver of the vehicle, comprising the following steps, while the adaptive cruise control module is activated: - following a vehicle stop, check that at least one descriptive element of a driving situation meets at least one predefined restart condition; - if at least one descriptive element meets at least one restart condition, check that the vehicle driver is attentive; - if the vehicle driver is attentive, automatically restart the vehicle for longitudinal speed control by the adaptive speed control module.

[0015] Thus, the invention allows the vehicle to restart automatically, after an active check that the driver is paying attention. It is therefore unnecessary to limit The period after shutdown during which automatic restart is possible, as offered by prior art solutions. This allows for an improved user experience associated with the automatic restart function after shutdown, while maintaining a high level of security.

[0016] According to embodiments, the verification that the driver of the vehicle is attentive can be based on at least one image captured by a camera of the vehicle, the camera being oriented so as to include the driver in a field of view of the camera.

[0017] Such a camera may be part of a driver monitoring system, also called DMS, with which the vehicle is equipped, in which case the invention may take advantage of equipment already present in the vehicle.

[0018] In addition, the verification that the driver of the vehicle is attentive can be based on a comparison between a level of attention of the driver and a predefined threshold, the level of attention being determined from at least one image captured by the camera.

[0019] Thus, automatic restart after stopping is only permitted for a high level of driver attention, or for high levels of driver attention, thereby enhancing the safety associated with the ACC function. Furthermore, the driver's attention level can be directly derived from the vehicle's DMS system, making it possible to utilize information already available within the vehicle.

[0020] According to embodiments, the method may further include, in the event of verification that the driver is not attentive after having verified that at least one descriptive data satisfies at least one restart condition, the dissemination of an audible and / or visual alert in the vehicle.

[0021] Thus, it is permissible to draw the driver's attention when the driver is inattentive and the driving situation allows the vehicle to restart.

[0022] In addition, following the dissemination of the alert, the method may include a further check that the driver is attentive for a predetermined period of time following the dissemination of the alert, and, if the driver is attentive during the period, an automatic restart of the vehicle for longitudinal speed control by the adaptive speed control module.

[0023] Thus, automatic restarting after stopping is permitted in a safe manner, including when the driver is not initially attentive.

[0024] In addition, if the driver is not attentive at the end of the period, the procedure may further include: - detect one driver action among at least one predetermined action after the expiry of the period, and; - following detection of the action, automatically restart the vehicle for longitudinal speed control by the adaptive speed control module, after a further check that at least one descriptive piece of information of a current driving situation satisfies at least one restart condition.

[0025] Thus, as a last resort, automatic restart of the vehicle is permitted if the driver explicitly requests it. Therefore, driver action is only required after their level of attention has been checked twice, before and after the alert is issued.

[0026] In addition or as an alternative, if the driver is not attentive at the end of the period, the method may further include: - detect one driver action among at least one predetermined action after the expiry of the period, and; - following detection of the action, deactivate the adaptive speed control module, for manual control of the vehicle's longitudinal speed.

[0027] Thus, the driver can, if he so requests after the alert has been broadcast, take back manual control of the vehicle.

[0028] As a further complement or alternative, if no action by the driver is detected among a predetermined action after the expiry of the period, the method may include the broadcasting of a new audible and / or visual alert in the vehicle.

[0029] Thus, the driver is alerted several times in case of inattention before restarting the vehicle, which helps to strengthen the safety associated with the driving situation.

[0030] A second aspect of the invention relates to a computer program comprising instructions for implementing the method according to the first aspect of the invention, when these instructions are executed by a processor.

[0031] A third aspect of the invention relates to an adaptive speed control module for a vehicle, said module being capable of controlling the longitudinal speed of the vehicle without manual control by a driver of the vehicle, and comprising a processor configured to, while the adaptive speed control module is activated: - following a vehicle stop, verify that at least one descriptive element of a driving situation satisfies at least one predefined restart condition; - if at least one descriptive element satisfies at least one restart condition, verify that the vehicle driver is attentive; - if the vehicle driver is attentive, automatically restart the vehicle for longitudinal speed control by the adaptive speed control module.

[0032] Other features and advantages of the invention will become apparent from an examination of the detailed description below, and the accompanying drawings in which:

[0033] [Fig-1] illustrates a motor vehicle according to embodiments of the invention;

[0034] [Fig.2] is a diagram illustrating the steps of a process according to embodiments of the invention;

[0035] [Fig.3] illustrates an adaptive speed control module of a vehicle driving assistance system, according to embodiments of the invention.

[0036] Fig. 1 illustrates a motor vehicle 100, according to embodiments of the invention.

[0037] The vehicle 100 may further include a vehicle driver assistance system 101, also called an AD AS system, for "Advanced Driver Assistance Systems". The AD AS system 101 is capable of implementing at least one driver assistance function based in particular on data from a set 104 of at least one vehicle sensor.

[0038] The term "driving assistance" for a vehicle means any method capable of assisting the driving of the vehicle. This method may consist of partially or fully steering the vehicle, providing any type of assistance to a person driving the vehicle, as well as performing other functions such as those enabling energy savings and / or the preservation or protection of vehicle components.

[0039] The AD AS 101 system improves driving comfort and safety and can protect certain vehicle components in certain driving situations, by taking advantage of data from vehicle sensors 104, such as radar or lidar data, cameras and / or geolocation devices, but also based on information provided by other vehicle modules or devices.

[0040] No restrictions are attached to the driver assistance functions implemented by the AD AS 101 system.

[0041] According to the invention, the AD AS system includes at least one module 102 dedicated to an adaptive cruise control function, or ACC in English, for "Adaptive Cruise Control", referred to as module ACC 102 in the following.

[0042] As previously explained, the ACC module allows automated control of the longitudinal speed of the vehicle 100, based on descriptive data of the driving situation of the vehicle 100, the descriptive data being obtainable from the assembly 104 of at least one sensor.

[0043] As previously stated, the vehicle 100 includes an assembly 104 comprising N sensors, where N is an integer greater than or equal to 1. There are no restrictions on the number of sensors or the types of sensors with which the vehicle is equipped. Vehicle 100. As an example, vehicle 100 may include one or more of the following sensors: - a radar; - a lidar; - a suitable sensor from an anti-lock braking system, or ABS for "Anti-Braking System" in English; - a camera pointed towards a scene outside the vehicle; - any other sensor on vehicle 100 capable of acquiring descriptive data of the driving situation.

[0044] According to the invention, the ACC module 102 is capable of implementing a vehicle restart function, or stop and go function, after a deceleration of the vehicle 100 until the vehicle comes to a stop, as described below with reference to [Fig.2].

[0045] The vehicle 100 may further include a camera 103 capable of obtaining descriptive images of the vehicle's interior, arranged in particular to include the driver's upper body, preferably their face, within its field of view. The camera 103 may be a camera from a driver monitoring system, also known as a DMS (Driver Monitoring System). The camera 103 may, in particular, be coupled with an image analysis module, not shown in [Fig. 1], capable of analyzing the images captured by the camera 103 to deduce the driver's level of attention. There is no restriction on the number of driver attention levels. For example, by way of simplification, the DMS may determine the driver's attention level as either attentive or inattentive.

[0046] The vehicle 100 may include at least one assembly 107 comprising at least one loudspeaker, and preferably several loudspeakers. According to the invention, the ACC module 102 is capable of controlling the assembly 107, in particular for the audible broadcast of an alert as described below.

[0047] The vehicle 100 may further include a screen 107 capable of displaying information to the vehicle's user(s). The screen 107 may, for example, be located at the front of the vehicle, in a central position on the dashboard. According to the invention, the ACC module 102 is capable of controlling the screen 107 to display a visual alert as described below.

[0048] The vehicle 100 may further include a user interface 105 capable of receiving user input that triggers an action indicating activation or deactivation of the ACC function implemented by the ACC module 102. The user interface 105 may, for example, be a button on the dashboard capable of receiving a press from the user. Alternatively, the ACC function may be deactivated by pressing on an accelerator pedal or on a brake pedal of vehicle 100, in which case the user interface 105 may be such an accelerator pedal.

[0049] According to some embodiments, the screen 107 is a touchscreen capable of displaying a graphical interface controlled, in particular at least partially, by the ACC module 102, for displaying information and touch zones, such as touch buttons, allowing a user to control vehicle functions. To this end, the touchscreen 107 is capable of receiving touch input from the user on one or more of the touch zones displayed in the graphical interface. In embodiments where the screen 107 is a touchscreen, the ACC function can be activated and deactivated by touch input on the screen 107, in which case the user interface 105 described above is optional.

[0050] In some embodiments, the entire touchscreen is touch-sensitive. Alternatively, only a portion of the touchscreen is touch-sensitive, thus capable of receiving touch input from the user, while another portion of the touchscreen is not touch-sensitive and is used solely to display information to the user.

[0051] No restrictions are attached to the technology associated with the touch screen, which may be of the capacitive type or of the resistive type, for example.

[0052] Fig. 2 is a diagram illustrating the steps of a process according to embodiments of the invention.

[0053] The method described with reference to [Fig.2] can be implemented in the vehicle 100 described with reference to [Fig.1], in particular by the ACC module 102 described previously.

[0054] At a step 200, the ACC function implemented by the ACC module 102 is activated, for example, by the vehicle driver via user input on the user interface 105 or on the screen 107 when it is a touchscreen. Within the scope of the invention, the ACC function 102 is at least a Level 2 ADAS function, requiring no manual intervention from the driver for controlling the longitudinal speed of the vehicle 100. In particular, the driver does not have to press the brake or accelerator pedals when the ACC function is activated.

[0055] The ACC function is implemented following step 200 on the basis of descriptive information of the driving situation captured by assembly 104 previously described.

[0056] At step 201, the ACC module 102 reduces the speed of vehicle 100 to a stop position, corresponding to zero speed. There are no restrictions on the driving situation leading to such a stop: it could be a stop sign, a red light, or deceleration to a stop position of another vehicle located in front of vehicle 100.

[0057] In the stop position, the ACC 102 module no longer controls the vehicle speed, which remains at 0 until the vehicle is restarted.

[0058] At step 202, the ACC module 102 determines, based on descriptive information of the current driving situation, whether the descriptive information satisfies at least one restart condition associated with the driving situation. No restrictions are attached to the at least one restart condition, which may be: - in the case of stopping at a red light, a first condition for restarting may be the change from red to green light and a second condition for restarting may be the absence of a pedestrian on a pedestrian crossing; - in the case of stopping at a stop sign, a restart condition may be the absence of a vehicle on a lane to be crossed or joined; - in the case of stopping behind another vehicle, a restart condition may be a restart of the other vehicle and a distance with the other vehicle greater than a given threshold.

[0059] Thus, different restart conditions can be predefined for different driving situations.

[0060] If the descriptive information of the driving situation does not satisfy at least one restart condition among the at least one restart condition, then the process returns to step 201, and the vehicle 100 is kept stationary, until a next test of step 202. Step 202 can thus be repeated at a predefined frequency, the frequency preferably being greater than 1 second so as to ensure a high responsiveness of the restart function after stopping according to the invention.

[0061] If the descriptive information of the driving situation satisfies at least one restart condition, the process proceeds to step 203.

[0062] In step 203, the ACC 102 module checks that the vehicle driver is attentive. If so, the process proceeds to step 204. Otherwise, if the driver is not attentive, the process proceeds to step 205.

[0063] There are no restrictions on how the ACC module 102 verifies that the driver is attentive. For example, the ACC module 102 may preferably receive information about the driver's attention from the Driver Monitoring System (DMS), which includes the camera 103 and the aforementioned analysis module. For example, the ACC module 102 may receive a driver attention level from the DMS and may determine whether the driver is attentive or not at step 203, based on the received attention level. The received attention level may, for example, be compared to a predetermined threshold to determine whether the driver is attentive or not.

[0064] At step 204, if it is verified that the driver is paying attention during step 203, the ACC module 102 restarts the vehicle 100, and resumes control of the longitudinal speed of the vehicle 100, according to descriptive information of the driving situation.

[0065] Thus, the invention advantageously enables the implementation of an automatic restart function after stopping by an ACC module, without requiring intervention from the driver, including if a long period, for example more than a few seconds, for example more than three seconds, has elapsed while the vehicle is stopped, i.e. between steps 201 and 202. Indeed, the period of several seconds used in the prior art is no longer necessary since a check of the driver's attention is prior to the automatic restart after stopping of the vehicle 100.

[0066] At step 205, if the ACC module 102 determines that the driver is not paying attention at step 203, the ACC module 102 can issue an alert to the driver, thereby increasing the driver's level of attention. There are no restrictions on the format of such an alert, which can be an audible alert emitted by controlling the system 106 from at least one speaker, or it can be a visual alert displayed on the screen 107.

[0067] Following step 205, the ACC 102 module verifies that, during a predetermined initial period after the alert in step 205, the driver is attentive. Step 205 is thus comparable to step 203, except that a timer is also initialized to a predetermined duration.

[0068] Again, the ACC 102 module can obtain descriptive information about the driver's attention, updated with respect to step 203, from the previously described DMS system. The descriptive information about the driver's attention can be the previously described level of attention.

[0069] If it is verified that the driver is attentive before the expiry of the first predetermined period, the process proceeds to step 204 described previously, and an automatic restart after stopping can be implemented by the ACC 102 module.

[0070] However, if, at the end of the first predetermined period, the ACC 102 module determines that the driver is still not attentive, the process proceeds to step 207. For example, during the predetermined period before the timer expires, the ACC 102 module can check the driver's attention level several times to determine whether the driver is attentive or not. If it is determined that the driver is attentive during the predetermined period, the process proceeds directly to step 204. Otherwise, the timer expires and the process proceeds to step 207.

[0071] At step 207, the ACC 102 module determines whether a driver action is detected or not, in particular whether a predetermined driver action is detected or not, after the expiration of the first period. The driver's action could, for example, be an action on the user interface 105 described previously, and / or on the screen 107 when it is a touchscreen. Examples of driver actions are described below.

[0072] If no action by the driver is detected, for example if no predetermined action by the driver is detected at the end of a second period of N seconds starting at the expiry of the first predetermined period, N being predetermined, step 205 can be repeated in order to broadcast a new alert, so as to increase the driver's level of attention.

[0073] If a first predetermined action is detected, the process proceeds to step 209. During step 209, the ACC 102 module is deactivated and the driver resumes manual control of the vehicle's longitudinal speed.

[0074] The first predetermined action can be a press on the accelerator pedal or on the brake pedal, or a press on the user interface 105 or on the screen 106 to deactivate the ACC function implemented by the ACC module 102. Such a first action can thus be detected by the ACC module 102 by receiving a signal from the user interface 105 or from the screen 106.

[0075] If a second predetermined action is detected, different from the first predetermined action, the process can proceed to step 208. During step 208, the driver manually reactivates the automatic restart after the ACC module 102 has stopped, and the process returns to step 202 described earlier to verify that at least one restart condition is met. When at least one restart condition is met, the process returns to step 203 to verify that the driver, having previously intentionally implemented the second predetermined action, is still attentive.

[0076] No restriction is attached to the second predetermined action which can be a predetermined action on the user interface 105 or on the screen 106, associated with a deactivation of the ACC function 102.

[0077] Such a second action can thus be detected by the ACC module 102 by receiving a signal from the user interface 105 or from the screen 106.

[0078] Figure 3 shows the structure of an ACC adaptive speed control module 102, according to embodiments of the invention.

[0079] The ACC 102 device includes a processor 301 configured to communicate unidirectionally or bidirectionally, via one or more buses or via a direct wired connection, with a memory 302 such as a Random Access Memory (RAM), a Read Only Memory (ROM), or any other type of memory (Flash, EEPROM, etc.). Alternatively, the memory 302 comprises several memories of the aforementioned types.

[0080] The memory 302 is capable of storing, permanently or temporarily, at least some of the data used and / or resulting from the implementation of the process described with reference to [Fig.2].

[0081] In particular, memory 302 can store at least one restart condition, a command corresponding to the audible and / or visual alert, the first predetermined action and / or the second predetermined action.

[0082] The processor 301 is capable of executing instructions, stored in memory 302, for the implementation of the steps of the process according to the invention, described with reference to [Fig. 2]. Alternatively, the processor 301 can be replaced by a microcontroller designed and configured to perform the steps of the process according to the invention, described with reference to [Fig. 2].

[0083] The ACC module 102 includes a first interface 303 capable of receiving information captured from the assembly 104 of at least one sensor.

[0084] The ACC module 102 includes a second interface 304 capable of receiving descriptive information about the driver's attention from the camera 103.

[0085] The ACC 102 module includes a third interface 305 capable of receiving a signal from the user interface 105, indicating a user action on the user interface.

[0086] The ACC module 102 includes a fourth interface 306 capable of transmitting the alert to be broadcast to the assembly 106 of at least one speaker and / or to the screen 107.

[0087] The present invention is not limited to the embodiments described above by way of example; it extends to other variants.

Claims

Demands

1. A method for controlling a restart function after a stop, implemented by an adaptive cruise control module (102) of a vehicle (100), the adaptive cruise control module being capable of controlling a longitudinal speed of the vehicle without manual control by a driver of the vehicle, comprising the following steps, while the adaptive cruise control module is activated: - following a stop (201) of the vehicle, verify (202) that at least one descriptive data of a driving situation satisfies at least one predefined restart condition; - if at least one descriptive data satisfies at least one restart condition, verify (203) that the driver of the vehicle is attentive; - if the driver of the vehicle is attentive, automatically restart (204) the vehicle for longitudinal speed control by the adaptive cruise control module.

2. A method according to claim 1, wherein the verification (203) that the driver of the vehicle (100) is attentive is based on at least one image captured by a camera (103) of the vehicle, the camera being oriented so as to include the driver in a field of view of the camera.

3. A method according to claim 2, wherein the verification (203) that the driver of the vehicle (100) is attentive is based on a comparison between a level of driver attention and a predefined threshold, the level of attention being determined from at least one image captured by the camera (103).

4. A method according to any one of the preceding claims, further comprising, in the event of verification that the driver is not attentive after having verified that at least one descriptive data satisfies at least one restart condition, the diffusion (205) of an audible and / or visual alert in the vehicle (100).

5. A method according to claim 4, further comprising, following the dissemination (205) of the alert, a further check (206) that the driver is attentive for a predetermined period of time following the dissemination of the alert, and, if the driver is attentive during the period, an automatic restart (204) of the vehicle for a longitudinal speed control by the adaptive speed regulation module.

6. A method according to claim 5, wherein, if the driver is not attentive at the end of the period, the method further comprises: - detecting (207) an action of the driver from among at least one predetermined action after the expiration of the period, and; - following detection of the action, automatically restarting (208; 204) the vehicle for longitudinal speed control by the adaptive speed control module after a further check (202) that at least one descriptive piece of information of a current driving situation satisfies at least one restart condition.

7. A method according to claim 5 or 6, wherein, if the driver is not attentive at the end of the period, the method further comprises: - detecting (207) an action of the driver from among at least one predetermined action after the expiration of the period, and; - following detection of the action, deactivating (209) the adaptive speed control module (102), for manual control of the longitudinal speed of the vehicle (100).

8. A method according to any one of claims 5 to 7, wherein, in the event of no detection of a driver action among a predetermined action after the expiry of the period, a new audible and / or visual alert is broadcast in the vehicle.

9. Computer program comprising instructions for carrying out the method according to any one of the preceding claims, when such instructions are executed by a processor (301).

10. Adaptive speed control module (102) of a vehicle (100), said module being capable of controlling a longitudinal speed of the vehicle without manual control by a driver of the vehicle, and comprising a processor (301) configured to, while the adaptive speed control module is activated: - following a stop of the vehicle, verify that at least one descriptive data of a driving situation satisfies at least one predefined restart condition; - if at least one descriptive data satisfies at least one restart condition, verify that the driver of the vehicle is attentive; - if the vehicle driver is attentive, automatically restart the vehicle for longitudinal speed control by the adaptive speed control module.

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