Method for determining a current value of an occupancy parameter associated with a portion of a space located in the vicinity of a land motor vehicle

Abstract

The invention relates to a method for determining a current value of an occupancy parameter relating to a portion of a space situated in the vicinity of a land motor vehicle, an associated system and an associated land motor vehicle.

Description

Technical Field

[0001] The present invention relates to the field of driver assistance systems for land motor vehicles. In particular, the invention relates to a method for determining at least one current value of at least one occupancy parameter relating to a portion of a space located in the vicinity of a land motor vehicle. The invention applies in particular to motor vehicles. Background Art

[0002] It is known that current driver assistance systems (especially those for assisting autonomous driving) usually base driver assistance functions (such as emergency braking, lateral avoidance, lane tracking, etc.) on the perception of the driving environment, which is determined by using detection instruments of various properties (lidar, radar, camera, ultrasonic sensor, etc.) that are now configured in most vehicles. Moreover, in most cases, the perception of the driving environment is established by the driver assistance system based on the data generated by these detection instruments. In some cases, this perception of the driving environment is visualized in the form of an occupancy grid, which is established to cover a large or small space located near the vehicle. In this case, the evolution of the occupancy of the space occupied by obstacles or objects is defined by, for example, using a state variable that characterizes the occupancy state, and the state variable is defined for each cell of the grid (that is, for all parts of the space considered to be located near the vehicle). Therefore, the state variable can evolve according to the occupancy state of the cells of the occupancy grid to characterize at least the following states: a vacant state (i.e., a state in which no object / obstacle is located in the cell), an occupied state (i.e., a state in which, in contrast to the previous state, at least one object / obstacle is located in the cell) and optionally an uncertain state (the uncertain state characterizes an uncertain (or unknown) evaluation of whether the considered cell is occupied).

[0003] It is therefore understood that current driver assistance systems base the provision of driver assistance functions primarily on the perception of the driving environment established by means of an occupancy grid, the accuracy and reliability of which depend on the accuracy with which the occupancy grid can be established. In fact, if the driving environment cannot be accurately determined, it is not possible to expect to establish a reliable and safe driver assistance function. In addition, it is obvious that there are particularly critical situations when selecting in order to assign an occupied state or a vacant state to a cell of the grid. However, very often, current driver assistance systems do not provide additional safety mechanisms that can better track state changes that can have direct consequences for the safety of the driver assistance function. In this sense, such systems are therefore not able to provide a driver assistance function that is as safe as possible. Summary of the invention

[0004] The present invention aims to provide a method to overcome these disadvantages. More specifically, the present invention aims to provide a method and system that helps to improve the accuracy of driving environment perception, so as to provide better detection of obstacles and thus provide safer driving assistance functions.

[0005] To this end, the object of the present invention is to provide a method for determining at least one current value of at least one occupancy parameter relating to a portion of a space situated in the vicinity of a land motor vehicle, characterized in that the method comprises the following steps:

[0006] - obtaining a previous value of the occupancy parameter, a current value of the occupancy counter and a current value of the delay counter, and

[0007] - determining a current value of the occupancy parameter by using a previous value of the occupancy parameter, a current value of the occupancy counter and a current value of the delay counter.

[0008] According to one variant, the method may include: a step intended to determine whether a previous value of the occupancy parameter represents an uncertain assessment of whether the portion is occupied, and when the previous value of the occupancy parameter represents an uncertain assessment of whether the portion is occupied, a step intended to determine a current value of the occupancy parameter using data generated based on a signal emitted by a detection instrument configured in the vehicle, a step intended to increment the occupancy counter, and a step intended to restart the delay counter.

[0009] According to another variant, the method may include: when the previous value of the occupancy parameter represents a definitive assessment of whether the portion is occupied, a step aimed at determining whether a signal is emitted by the detection instrument confirming the presence of an object in the portion, and when a signal is emitted by the detection instrument confirming the presence of an object in the portion, a step aimed at using a predictive model to determine the current value of the occupancy parameter, a step aimed at incrementing the occupancy counter, and a step aimed at restarting the delay counter.

[0010] According to another variant, the method may comprise a step aimed at determining whether the portion is positioned in the detection range of the detection instrument when the detection instrument emits a signal confirming the absence of any object in the portion.

[0011] According to another variant, the method may include: when the part is positioned in the detection range of the detection instrument, a step aimed at determining whether the occupancy counter is greater than a first predefined threshold value, and when the occupancy counter is greater than the first predefined threshold value, a step aimed at determining whether the delay counter is less than or equal to a second predefined threshold value, and when the delay counter is less than or equal to the second predefined threshold value, a step aimed at assigning the previous value of the occupancy parameter to the current value of the occupancy parameter, and a step aimed at incrementing the delay counter.

[0012] According to another variant, the method may comprise a step aimed at determining the current value of the occupancy parameter using a prediction model, a step aimed at restarting the occupancy counter, and a step aimed at restarting the delay counter when the occupancy counter is less than the first threshold.

[0013] According to another variant, the method may comprise a step aimed at determining the current value of the occupancy parameter using a prediction model, a step aimed at restarting the occupancy counter, and a step aimed at restarting the delay counter when the value of the delay counter is greater than the second threshold.

[0014] The invention also aims to provide a computer system for determining at least one current value of at least one occupancy parameter relating to a portion of a space situated in the vicinity of a land motor vehicle, the system comprising means for implementing a method as defined above.

[0015] According to a variant, the system may comprise at least one computer and a storage means storing inside at least one program for executing the steps according to a determination method implemented by the system.

[0016] The invention also aims at providing a land motor vehicle comprising a system as defined above. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Other features and advantages of the present invention will become more apparent from the following detailed description and the accompanying drawings, in which:

[0018] Figure 1 is a block diagram of a determination system according to the present invention, and

[0019] Figure 2 is a flow chart showing some steps of the determination method according to the present invention. DETAILED DESCRIPTION

[0020] like Figure 1As shown in , a determination system 100 for determining at least one current value of at least one occupancy parameter according to the present invention comprises an information processing unit 101, a data storage carrier 102, an input and output component 103, and an oracle 104, wherein the at least one occupancy parameter is related to a part of a space located near a land motor vehicle, and the information processing unit comprises one or more processors. Preferably, the oracle 104 comprises a module for establishing a prediction model so that the oracle 104 can use the prediction model to generate a value of an occupancy parameter relative to a part of the space based on the data it receives. Preferably, the oracle 104 is based on an implementation of the Dempster-Shafer theory.

[0021] According to some embodiments, system 100 is loaded on a land motor vehicle (e.g., a car) and is distributed among one or more computers. According to other embodiments of the present invention, system 100 includes one or more computers, one or more servers, one or more supercomputers and / or any combination of one of these computer systems. Some embodiments are also contemplated in which some elements of system 100 are partially housed on a land motor vehicle and on one or more computers, while other elements are distributed on one or more remote servers.

[0022] According to a preferred embodiment, the system 100 is an integral part of a computer of a driving assistance system (not shown) of a vehicle, which relies on a plurality of detection instruments (not shown) arranged in the vehicle. Preferably, the driving assistance system comprises at least one laser remote sensing detection instrument, a radio detection instrument, a camera and / or an ultrasonic sensor, each of which preferably comprises a signal processing module, which is capable of generating data based on the received signal. Alternatively or cumulatively, the driving assistance system comprises a central processing module, which is capable of generating data based on the signal transmitted by the detection instrument. Typically, the driving assistance system also comprises one or more computers, which control the operation of some components of the vehicle according to established functions and according to the data generated by the detection instrument to provide various driving control functions (e.g., emergency braking assistance, obstacle avoidance, lane tracking). Alternatively or cumulatively, the driving assistance system also comprises additional elements suitable for and constructed for integration in an intelligent transportation system.

[0023] Alternatively, according to another specific embodiment, the system 100 is hosted by an independent computer and interacts with a computer of a driver assistance system of the vehicle to obtain data generated by the detection instrument. Alternatively, the data is generated by the driver assistance system and stored in the storage medium 102 of the system 100 by the driver assistance system.

[0024] All elements described above contribute to enabling the system 100 to implement a determination method for determining at least one current value of at least one occupancy parameter associated with a portion of a space located in the vicinity of a land motor vehicle, as described below.

[0025] like Figure 2 As shown in , according to step 201, the system 100 obtains a previous value of an occupancy parameter, a current value of an occupancy counter, and a current value of a delay counter. Next, according to another step 202, the system 100 determines a current value of the occupancy parameter by using the previous value of the occupancy parameter, the current value of the occupancy counter, and the current value of the delay counter.

[0026] To this end, the system 100 first determines whether the previous value of the occupancy parameter represents an uncertain evaluation of whether the portion is occupied. As mentioned above, the uncertain evaluation corresponds to the situation that it is not possible to determine whether the considered space portion is vacant or occupied. When the previous value of the occupancy parameter represents an uncertain evaluation of whether the portion is occupied, the system 100 obtains data generated based on at least one signal emitted by at least one detection instrument configured in the vehicle. On this sole basis, the system determines the current value of the occupancy parameter of the space portion. Next, the system 100 increments the occupancy counter and restarts the delay counter. In other words, based only on the signals and data generated by one or more detection instruments, the space portion whose occupancy state was previously uncertain is in the state of being assigned the current occupancy state. The occupancy counter is logically incremented because when it is not known whether the space portion was previously vacant or occupied, it is preferred to consider the space portion to be occupied at this stage. In fact, it is agreed that when the perception of the driving environment is used as the only basis for the provision of driving assistance functions, it is always better to consider that obstacles exist, rather than making mistakes on the contrary.

[0027] Next, in another step, when the previous value of the occupancy parameter represents a definitive assessment of whether the portion is occupied (i.e., it is possible to determine whether the spatial portion is vacant or occupied), the system 100 determines whether a signal confirming the presence of an object in the portion is emitted by the detection instrument. When a signal confirming the presence of an object in the portion is emitted by the detection instrument, the system queries the oracle 104 to determine the current value of the occupancy parameter by using a predictive model. Next, the system 100 increments the occupancy counter and restarts the delay counter.

[0028] Conversely, when the detection instrument sends a signal confirming the absence of any object in the portion, the system 100 proceeds to determine whether the portion is positioned within the detection range of the detection instrument.

[0029] Next, when the portion is positioned in the detection range of the detection instrument, the system 100 determines whether the occupancy counter is greater than a first predefined threshold. When the occupancy counter is greater than the first predefined threshold, the system 100 determines whether the delay counter is less than or equal to the second predefined threshold, and when the delay counter is less than or equal to the second predefined threshold, the system 100 assigns the previous value of the occupancy parameter to the current value of the occupancy parameter and increments the delay counter. Through these steps, the system creates a safety guarantee mechanism that implements a delay to postpone the occupancy state change of the space portion that is often occupied, which, as already mentioned, can have a direct consequence on the safety of the driving assistance function. Conversely, when the value of the delay counter is greater than the second threshold, the system 100 uses a predictive model to determine the current value of the occupancy parameter, restarts the occupancy counter, and restarts the delay counter. Through these steps, the system 100 ensures that the execution of the safety guarantee mechanism for the space portion that is often occupied is limited to a predefined duration, which depends on the second threshold.

[0030] Otherwise, when the detection instrument sends a signal confirming the absence of any object in the portion, when the portion is located in the detection range of the detection instrument, and when the occupancy counter is less than the first threshold, the system 100 uses the prediction model to determine the current value of the occupancy parameter, restarts the occupancy counter, and restarts the delay counter. Through these steps, the system 100 adapts the safety guarantee mechanism to make the changes in the state related to the space portion that is not often occupied subject to less important safety guarantee terms.

[0031] Therefore, in the above described method and system aspects according to the present invention, functional blocks are provided for enabling a driver assistance system to establish a more accurate perception of the driving environment and thus provide a more reliable and safer driver assistance function.

[0032] The invention is not limited to the embodiments described above which are shown merely as examples, but extends to other embodiments, in particular embodiments formed by combining some features described in connection with some embodiments with other features described in connection with other embodiments within the scope of capabilities of a person skilled in the art.

Claims

1. A method for determining, by a computer system (100), at least one current value of at least one occupancy parameter associated with a portion of a space located in the vicinity of a land motor vehicle, characterized in that The determination method comprises the following steps: - obtaining a previous value of the occupancy parameter, a current value of the occupancy counter and a current value of the delay counter, and - determining a current value of the occupancy parameter by using a previous value of the occupancy parameter, a current value of the occupancy counter and a current value of the delay counter, Furthermore, the determination method comprises a step aimed at determining whether a previous value of the occupancy parameter represents an uncertain assessment of whether the portion is occupied, and when the previous value of the occupancy parameter represents an uncertain assessment of whether the portion is occupied, a step aimed at determining a current value of the occupancy parameter using data generated based on a signal emitted by a detection instrument arranged in the land motor vehicle, a step aimed at incrementing the occupancy counter, and a step aimed at restarting the delay counter, Furthermore, the determination method comprises: a step for determining whether a signal confirming the presence of an object in the portion is emitted by the detection instrument when a previous value of the occupancy parameter represents a determined evaluation of whether the portion is occupied, and a step for determining a current value of the occupancy parameter using a prediction model when a signal confirming the presence of an object in the portion is emitted by the detection instrument, a step for incrementing the occupancy counter, and a step for restarting the delay counter, Furthermore, the determination method comprises: when the detection instrument sends a signal confirming that no object exists in the portion, a step of determining whether the portion is located within a detection range of the detection instrument, Furthermore, the determination method includes: when the part is positioned in the detection range of the detection instrument, a step for determining whether the occupancy counter is greater than a first predefined threshold value, and when the occupancy counter is greater than the first predefined threshold value, a step for determining whether the delay counter is less than or equal to a second predefined threshold value, and when the delay counter is less than or equal to the second predefined threshold value, a step for assigning the previous value of the occupancy parameter to the current value of the occupancy parameter, and a step for incrementing the delay counter.

2. The determination method according to claim 1, characterized in that: The determination method comprises a step aimed at determining the current value of the occupancy parameter using a prediction model, a step aimed at restarting the occupancy counter, and a step aimed at restarting the delay counter when the occupancy counter is less than the first predefined threshold.

3. The determination method according to claim 1, characterized in that: The determination method comprises a step aimed at determining the current value of the occupancy parameter using a prediction model, a step aimed at restarting the occupancy counter, and a step aimed at restarting the delay counter when the value of the delay counter is greater than the second predefined threshold.

4. A computer system (100) for determining at least one current value of at least one occupancy parameter associated with a portion of a space located in the vicinity of a land motor vehicle, characterized in that The computer system comprises components (101, 102, 103, 104) for implementing a determination method according to any of the preceding claims.

5. The computer system according to claim 4, characterized in that: The computer system comprises at least one computer (101) and a storage component (102) storing at least one program therein, wherein the at least one program is used to execute steps according to a determination method implemented by the computer system.

6. A land motor vehicle, characterized in that: The land motor vehicle comprises a computer system according to claim 4 or 5.

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