METHOD FOR MANAGING A LANE KEEPING FUNCTION PROVIDED BY A DRIVING ASSISTANCE SYSTEM OF A MOTORIZED LAND VEHICLE

Description

Technical field of the invention

[0001] The present invention relates to the field of driver assistance systems for motor vehicles. The invention specifically relates to a method for determining a point value of an operating parameter used to manage a lane-keeping assistance function provided by a driver assistance system for a motor vehicle, as well as to a computer system implementing such a method. The invention is particularly applicable to motor vehicles. State of the art

[0002] We know that current vehicle driver assistance systems, particularly those designed for autonomous driving assistance, generally base driver assistance features (e.g. emergency braking, lateral avoidance, lane keeping, etc.) on a perception of a driving environment determined by using various types of detection devices that are now arranged in most vehicles (LIDAR, RADAR, camera, ultrasonic sensors, etc.).

[0003] Among the features provided by some current vehicle driver assistance systems, lane keeping assist, particularly in the context of autonomous driving, helps to position and maintain the vehicle within a lane. Generally, this lane keeping assist is provided by using data and / or signals generated by at least one camera mounted in the vehicle, along with various devices that process this data and / or signals to determine the vehicle's position relative to one or more lanes and, if necessary, influence certain vehicle components, such as steering components, to ensure proper guidance and lane positioning.In addition, particularly when these features are intended to enable the implementation of autonomous driving procedures, current vehicle driver assistance systems are in most cases equipped with devices / equipment to allow the automatic activation and deactivation of these lane keeping assistance features.

[0004] A driver assistance system for use during vehicle operation is known from document DE102006004772. This system includes a control device that evaluates sensor signals and has lane departure warning and lane keeping assist functions that are activated and deactivated based on a confidential measurement. A vehicle movement assistance device is known from document EP2251238. A vehicle movement assistance device that determines a trajectory from captured images is known from document JP2014133477.

[0005] However, it has been observed that these mechanisms for automatically activating and deactivating lane-keeping assist features sometimes cause inconveniences. For example, it has been noted that certain situations can lead to repeated switching between an active state (i.e., a state in which lane-keeping assist is activated) and an inactive state (i.e., a state in which lane-keeping assist is deactivated). These repeated switchings are clearly detrimental, as they force the driver to remain constantly vigilant in case they need to take back control of the vehicle when lane-keeping assist is deactivated. This, of course, defeats the primary purpose of these features, which is to enable autonomous driving.

[0006] Furthermore, independently of the automated management of the activation of lane keeping assistance features, it is also observed that current driver assistance systems that provide such features produce erroneous guidance in certain situations, which is also particularly damaging in the context of autonomous driving. Presentation of the invention

[0007] The invention aims to provide a method to overcome these drawbacks. In particular, the invention aims to provide a method and a system that help limit unwanted switching between an active and an inactive state of a lane-keeping assistance function. As a secondary objective, the invention aims to provide a method and a system that can limit the risk of erroneous guidance.

[0008] To this end, the invention relates to a method for determining a point value of an operating parameter used to manage the activation and deactivation of a lane-keeping assistance feature provided by a driver assistance system for a motor vehicle, the method comprising the steps of: determine a point value of a confidence indicator quantifying a level of confidence in the perception of a traffic lane located near the vehicle by exploiting data generated using at least one detection device of the vehicle's driver assistance system, determine a previous value of the operating parameter, compare the point value of the confidence indicator with a first threshold value and a second threshold value lower than the first threshold value, and, when the point value of the confidence indicator is greater than or equal to the first threshold value, determine the point value of the operating parameter by increasing the previous value as long as it is less than a predefined maximum value, when the point value of the confidence indicator is less than the first threshold value and greater than or equal to the second threshold value,Determine the point value of the operating parameter by decreasing the previous value; when the point value of the confidence indicator is less than the second threshold value, assign a zero value to the point value of the operating parameter.

[0009] The term "lane keeping assist" refers to any type of assistance or autonomous driving system related to the lane. For example, it could be a driving procedure to keep the vehicle in its lane, to anticipate a lane change, to anticipate a lane departure in order to change direction, etc.

[0010] According to one variant, the process may include a step of disabling the lane keeping assist functionality when the point value of the operating parameter is less than a first setpoint value.

[0011] According to another variant, the process may include a step of enabling the lane keeping assist feature when the point value of the confidence indicator is greater than or equal to the first threshold value and the point value of the operating parameter is greater than or equal to a second setpoint value that is greater than the first setpoint value.

[0012] According to another variant, the step of making a reduction may consist of subtracting from the previous value a proportion of it and / or a first pre-established value selected according to the previous value.

[0013] According to another variant, the step of making an increase may consist of adding to the previous value a proportion of it and / or a second pre-established value selected based on the previous value.

[0014] The invention further relates to a computer system for determining a point value of an operating parameter used to manage the activation and deactivation of a lane keeping assistance feature provided by a driver assistance system of a motor vehicle, the system comprising means implementing a method as defined above.

[0015] According to one variant, the system may include at least one processor and storage means in which at least one program is stored for the execution of steps according to the determination process implemented by the system.

[0016] The invention further relates to a motorized land vehicle comprising a system as defined above. Brief description of the figures

[0017] Other features and advantages of the invention will become apparent upon examination of the detailed description below, and the accompanying drawings, in which: [ Fig. 1 ] is a block diagram of a determination system according to the invention, and [ Fig. 2 ] is a flowchart illustrating certain steps of a determination process according to the invention. Detailed description of the invention

[0018] As illustrated in the figure 1The system for determining a point value of an operating parameter used to manage a lane keeping assistance feature provided by a driver assistance system for a motor vehicle according to the present invention comprises an information processing unit 101, comprising one or more processors, a data storage medium 102, at least one input and output interface 103, enabling the reception of data / signals and the transmission of data / signals and, optionally, a digital signal processor 104 capable of receiving data, demodulating it, amplifying it, and this in accordance with the general knowledge of a person skilled in the art.

[0019] In some embodiments, the system 100 is installed in a motor vehicle, for example, a car, and is distributed among one or more control units. In the preferred embodiment, the system 100 is an integral part of a control unit of the vehicle's driver assistance system (not shown), which relies on a plurality of sensing devices (not shown) arranged in the vehicle. Preferably, the driver assistance system includes at least one laser remote sensing device, one radio sensing device, one camera, and / or one ultrasonic sensor, each preferably including a signal processing module capable of generating data based on received signals. Alternatively, or cumulatively, the driver assistance system includes a single signal processing module capable of generating data based on signals transmitted by each of the sensing devices.Conventionally, a driver assistance system also includes one or more computers / controllers which, according to established roles and based on signals / data generated by the detection devices, control the operation of certain vehicle components to contribute to the provision of various driver assistance features (e.g., emergency braking assistance, obstacle avoidance, lane keeping assist, etc.). In particular, to provide lane keeping assist, the vehicle's driver assistance system is capable of influencing certain vehicle components, including steering and / or vehicle dynamics control components, to ensure the vehicle is properly guided / maintained within a lane.Alternatively, according to another particular embodiment, the system 100 is hosted by an independent computer and interacts with a computer of the vehicle's driver assistance system to obtain the data generated using the detection devices. Alternatively, the data is generated by the driver assistance system and stored by it in the data storage medium 102 of the system 100.

[0020] For certain tasks related to specific steps in the process according to the invention described below, the system 100 interacts, preferably via its input / output interface 103, with the driver assistance system to obtain and utilize data generated using the vehicle's driver assistance system camera. Furthermore, in other steps of the process according to the invention described below, the system 100 also interacts with the driver assistance system to control the activation and deactivation of the lane-keeping assist function provided by the driver assistance system.

[0021] All the elements described above contribute to enabling system 100 to implement a method for determining a point value of an operating parameter used to manage a lane-keeping assistance feature provided by a driver assistance system for a motor vehicle, as described below.

[0022] As illustrated in the figure 2According to step 201, system 100 first determines a point value for a confidence indicator quantifying the level of confidence in the perception of a traffic lane located near the vehicle. To do this, system 100 obtains data generated by the driver assistance system using at least one detection device of the vehicle's driver assistance system, for example, the driver assistance system camera. Indeed, when the vehicle is moving, the camera regularly and / or continuously transmits signals that are interpreted by the driver assistance system, using, for example, an integrated digital signal processor, to generate this data that characterizes the vehicle's driving environment, including the presence and / or positioning of longitudinal and / or transverse marking lines (e.g., lane markings, edge lines, etc.).The data generated by the driver assistance system is therefore obtained / extracted / retrieved by system 100, either by interacting with the driver assistance system or directly from the data storage medium 102, to implement one or more processing steps to determine the point value of the confidence indicator. Preferably, the point value of the confidence indicator thus determined is between zero and one hundred, with a value of zero corresponding to zero confidence in the perception of a traffic lane and a value of one hundred corresponding to maximum confidence in the perception of a traffic lane. Thus, it is understood that system 100 determines, during this first step, a degree of certainty regarding the driver assistance system's ability to perceive the driving environment at a given moment.

[0023] Next, according to another step 202, the system 100 determines a previous value of the operating parameter. Indeed, following a previous implementation of the method according to the invention, the system 100 previously determined a value of the operating parameter, and this value was recorded in the data storage medium 102. Thus, by this step, the system 100 establishes a record of the historical value of the operating parameter over time.

[0024] Next, according to another step 203, the system 100 compares the point value of the confidence indicator with a first threshold value and a second threshold value that is lower than the first threshold value. Based on this comparison step, the system then determines the point value of the operating parameter. More specifically, when the point value of the confidence indicator is greater than or equal to the first threshold value, the system 100 determines the point value of the operating parameter by increasing the previous value, provided that the previous value is less than a predefined maximum value. For example, the system adds a proportion of the previous value of the operating parameter to it. Alternatively, the system 100 adds a predetermined value selected based on the previous value to the previous value.

[0025] Conversely, when the point value of the confidence indicator is less than the first threshold value and greater than or equal to the second threshold value, System 100 determines the point value of the operating parameter by decreasing the previous value. For example, System 100 subtracts a proportion of the previous value. Alternatively, System 100 subtracts a predetermined value selected based on the previous value. In a third case, when the point value of the confidence indicator is less than the second threshold value, System 100 sets the point value of the operating parameter to zero.

[0026] Finally, according to step 204, system 100 determines a control command governing the activation and / or deactivation of the lane-keeping assist function and transmits this command command to the driver assistance system. To do this, when the point value of the operating parameter is lower than a first predefined setpoint value, system 100 determines and transmits to the driver assistance system a control command that deactivates the lane-keeping assist function.Conversely, when the point value of the operating parameter is greater than or equal to a second setpoint value greater than the first setpoint value and the point value of the confidence indicator is greater than or equal to the first threshold value, the system 100 determines and then transmits to the driving assistance system a command order which authorizes the activation of the lane keeping assistance function.

[0027] Consequently, according to the method and system of the invention described above, the functional components are provided to enable a driver assistance system to control the activation and / or deactivation of a lane-keeping assist feature in such a way as to limit unintended switching between an active state of the lane-keeping assist feature and an inactive state thereof. Indeed, unlike known mechanisms, the method of the invention makes it possible to condition the activation and / or deactivation of the lane-keeping assist feature based on a history of the perception of the driving environment. Furthermore, the method and system of the invention make it possible to smooth the assessment of the driving context, thus avoiding overreacting to a situation that is too specific.Furthermore, by introducing a minimum threshold below which the operating parameter takes a zero value, the method and system according to the invention limit the possibility of erroneous guidance occurring, which, as has been observed, generally occurs when the perception of the driving environment is degraded by certain external factors (e.g., occlusion of the camera's field of view, weather conditions, absence of lane markings, confusion with the shadow cast by a signpost, etc.). Through these mechanisms, the method and system according to the invention thus prevent prolonged exposure to a moderately degraded perception situation that allows driving but carries a risk of the lane-keeping assist function producing erroneous guidance.

Claims

1. A method for determining, by a computer system (100), a point value of an operating parameter used by a driver assistance system for a motor vehicle to manage the activation and deactivation of a lane-keeping assistance feature, characterized in that the method comprises the steps of: - to determine a point value for a confidence indicator quantifying a level of confidence in the perception of a traffic lane located near the vehicle by exploiting data generated using at least one detection device of the vehicle's driver assistance system, - determine a previous value of the operating parameter, - compare the point value of the confidence indicator with a first threshold value and a second threshold value lower than the first threshold value, and, - When the point value of the confidence indicator is greater than or equal to the first threshold value, determine the point value of the operating parameter by increasing the previous value, provided that this is less than a predefined maximum value. - When the point value of the confidence indicator is less than the first threshold value and greater than or equal to the second threshold value, determine the point value of the operating parameter by decreasing the previous value. - when the point value of the confidence indicator is less than the second threshold value, assign a zero value to the point value of the operating parameter.

2. Method according to claim 1, characterized in that it comprises a step of causing the deactivation of the lane keeping assist functionality when the point value of the operating parameter is less than a first setpoint value.

3. Method according to claim 2, characterized in that it comprises a step of enabling the activation of the lane keeping assist functionality when the point value of the confidence indicator is greater than or equal to the first threshold value and the point value of the operating parameter is greater than or equal to a second setpoint value greater than the first setpoint value.

4. A method according to any one of the preceding claims, characterized in that the step of operating a reduction consists of subtracting from the previous value of the operating parameter a proportion of it or a first pre-established value selected according to the previous value of the operating parameter.

5. A method according to any one of the preceding claims, characterized in that the step of performing an increase consists of adding to the previous value of the operating parameter a proportion thereof or a second pre-established value selected according to the previous value of the operating parameter.

6. Computer system (100) for determining a point value of an operating parameter which is used by a driver assistance system of a motor vehicle to manage the activation and deactivation of a lane keeping assistance feature, characterized in that it includes means (101, 102, 103, 104) for implementing a method according to any one of the preceding claims.

7. System according to claim 6, characterized in that it comprises at least one processor (101) and storage means (102) in which at least one program is stored for the execution of steps according to the determination method implemented by the system.

8. Motorized land vehicle, characterized in that it comprises a system according to one of claims 6 or 7.