An autonomous driving path tracking and vehicle stability control cooperation method and system

Abstract

The application discloses an automatic driving path tracking and vehicle stability control cooperation method and system. The application determines whether a vehicle is in an automatic driving mode or a manual driving mode based on a driving mode judgment module. When the vehicle is in the manual driving mode, the driving action of the vehicle is controlled by a vehicle stability control module and a chassis fusion control module according to driver intention recognition. When the vehicle is in the automatic driving mode, the driving action of the vehicle is controlled by an automatic driving module, a limit working condition expansion control safety judgment module, a vehicle stability control module, a chassis fusion control module and the like. When the vehicle is in the automatic driving mode, the interaction between the automatic driving path tracking and the vehicle stability control, and the improvement of the vehicle stability control triggering logic can reduce the stability control triggering frequency and alleviate or even avoid the safety problems caused by the automatic driving system exit under the premise of ensuring safety in the scene of lane changing on low adhesion road and the like which is originally easy to trigger the vehicle stability control.

Description

Technical Field

[0001] The present invention relates to the field of automobile autonomous driving and intelligent chassis technology, and in particular to a method and system for coordinating autonomous driving path tracking and vehicle stability control. Background Art

[0002] In recent years, autonomous driving technology has matured, with production vehicles approaching Level 3 levels of autonomous driving. This has enabled autonomous driving systems to cover a growing number of operating conditions. As autonomous driving technology becomes more widely adopted, the issue of autonomous driving disengagement has gradually emerged, garnering attention from both academia and industry. A prominent example is the potential for autonomous vehicles, such as those changing lanes on slippery roads, to trigger vehicle stability control, causing the autonomous driving system to disengage and posing a safety hazard. Under these challenging conditions, mitigating or preventing the triggering of stability control while simultaneously completing autonomous lane changes remains a pressing challenge. Summary of the Invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] The present invention proposes a method for coordinating automatic driving path tracking and vehicle stability control, which can reduce or even avoid the phenomenon of automatic driving exit when automatically changing lanes on low-adhesion roads such as slippery ones, thereby ensuring the safety performance of the vehicle.

[0005] Another object of the present invention is to provide an autonomous driving path tracking and vehicle stability control collaborative system.

[0006] To achieve the above objectives, the present invention provides a method for coordinating autonomous driving path tracking and vehicle stability control, comprising:

[0007] S100 identifies vehicle driving mode;

[0008] S101 determines whether to enter the automatic driving mode; if it is identified as the manual driving mode, enter S109; if it is identified as the automatic driving mode, enter S102;

[0009] S109 performs driver intention analysis;

[0010] S110 calculates key states for determining vehicle stability;

[0011] S111 determines whether the key state exceeds the first stability trigger threshold in the current state; if it exceeds the first stability trigger threshold, enter S112; if it does not exceed the first stability trigger threshold, enter S113;

[0012] S112 activates the vehicle stability control algorithm and controls the chassis actuators;

[0013] S113 activates chassis fusion control to execute optimal distribution of actuators, and finally controls the chassis actuators;

[0014] S102 receives a current state stability trigger second threshold value;

[0015] S103 plans an autonomous driving path with the second threshold value as a hard constraint, and calculates a current stability decision key state;

[0016] S104 compares whether the stability decision key state exceeds a stability trigger first threshold value, if not, enters S108, if yes, enters S105;

[0017] S105 determines whether it exceeds a stability second threshold value, if it exceeds the second threshold value, enters S106, if it is determined that it does not exceed the second threshold value, enters S107;

[0018] S106 activates a vehicle stability control algorithm and controls the chassis actuators;

[0019] S107 determines whether a path tracking error and a vehicle stability trend are safe, if yes, enters S108, if not, enters S106;

[0020] S108 performs chassis fusion control with the stability second threshold value as a soft constraint, and finally controls the chassis actuators.

[0021] The autonomous driving path tracking and vehicle stability control cooperation method of the embodiment of the application can further have the following additional technical features:

[0022] In an embodiment of the application, when the vehicle is in a manual driving mode, according to a vehicle stability decision key state and a stability trigger first threshold value, it is determined whether to activate a vehicle stability control algorithm, if the stability decision key state exceeds the stability trigger first threshold value, the vehicle stability control algorithm is activated, and the movement of the vehicle is controlled according to a driver's intention and ideal steering characteristics; if the stability decision key state does not exceed the stability trigger first threshold value, a chassis actuator control command is distributed according to the driver's intention, and the movement of the vehicle is controlled;

[0023] When the vehicle is in an autonomous driving mode, a stability trigger second threshold value is received, and the planned path is dynamically adjusted with the stability trigger second threshold value as a hard constraint.

[0024] In one embodiment of the present application, according to the vehicle state information, when the vehicle stability decision key state is less than the first threshold of the current vehicle state stability trigger, the vehicle stability control program is not activated; when the vehicle yaw rate and other stability decision key states exceed the original stability trigger threshold in the current vehicle state and are less than the second stability trigger threshold in the current vehicle state, it is judged whether the current path tracking error and the vehicle stability trend are within the safe range, if yes, the vehicle stability control program is not activated, if not, the vehicle stability control program is activated; when the vehicle yaw rate and other stability decision key states exceed the second stability trigger threshold in the current vehicle state, the vehicle stability control program is activated.

[0025] In one embodiment of the present application, whether the current path tracking error and the vehicle stability trend are within the safe range includes:

[0026] If the deviation between the current vehicle actual path and the automatic driving planning path is less than the trajectory allowable deviation threshold, and the time exceeding the stability trigger threshold is less than the trajectory allowable deviation threshold, it is within the safe range, otherwise it is not within the safe range.

[0027] In one embodiment of the present application, the vehicle stability decision key state includes one or more combinations of yaw rate, center of mass side slip angle, vehicle speed, wheel speed, and road adhesion information.

[0028] In one embodiment of the present application, the chassis fusion control system receives the first stability trigger threshold and sets it as a soft constraint; when the stability control program is not activated, the automatic driving planning driving path is received, and the soft constraint is combined for motion control and execution control optimization distribution to control the motion of the vehicle; when the stability control program is activated, the received automatic driving planning driving path is locally adjusted to assist in maintaining the stability of the vehicle posture until the stability control algorithm exits.

[0029] To achieve the above purpose, another aspect of the present application provides an automatic driving path tracking and vehicle stability control cooperation system, comprising:

[0030] A driving mode judgment module is used to judge whether the vehicle is in manual driving mode or in automatic driving mode.

[0031] An automatic driving module is used to plan an automatic driving path.

[0032] A limit working condition expansion control safety judgment module is used to monitor whether it is in a controllable motion interval in the automatic driving mode, and to activate the vehicle stability control before serious instability occurs.

[0033] A vehicle stability control module is used to call a vehicle stability control algorithm in manual driving mode and automatic driving mode.

[0034] a chassis fusion control module for distributing chassis actuator control commands and controlling the motion of the vehicle in the manual driving mode, for constraining the motion control and optimizing the distribution of actuator control when the stability control is not activated, and for assisting the stability control to maintain the stability of the vehicle posture when the stability control is activated in the autonomous driving mode.

[0035] The automatic driving path tracking and vehicle stability control cooperation method and system of the embodiment of the present application redefine the relationship between the path tracking and vehicle stability control in the autonomous driving mode, greatly expand the available motion range in the autonomous driving mode, improve the application range of autonomous driving, and reduce the safety risks caused by the exit of autonomous driving.

[0036] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0037] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the accompanying drawings, in which:

[0038] Figure 1 is a flowchart of an automatic driving path tracking and vehicle stability control cooperation method according to an embodiment of the present application;

[0039] Figure 2 is a structural diagram of an automatic driving path tracking and vehicle stability control cooperation system according to an embodiment of the present application. DETAILED DESCRIPTION

[0040] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0041] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work should belong to the protection scope of the present application.

[0042] The automatic driving path tracking and vehicle stability control cooperation method and system according to the embodiments of the present application will be described below with reference to the accompanying drawings.

[0043] Figure 1FIG. 1 is a flow chart of a method for coordinating automatic driving path tracking and vehicle stability control according to an embodiment of the present invention. Figure 1 As shown, the method includes:

[0044] S100 identifies vehicle driving mode;

[0045] S101 determines whether to enter the automatic driving mode; if it is identified as the manual driving mode, enter S109; if it is identified as the automatic driving mode, enter S102;

[0046] S109 performs driver intention analysis;

[0047] S110 calculates key states for determining vehicle stability;

[0048] S111 determines whether the key state exceeds the first stability trigger threshold in the current state; if it exceeds the first stability trigger threshold, enter S112; if it does not exceed the first stability trigger threshold, enter S113;

[0049] S112 activates the vehicle stability control algorithm and controls the chassis actuators;

[0050] S113 activates chassis fusion control to optimize the distribution of actuators and finally controls the chassis actuators for control;

[0051] S102 receives a current state stability triggering second threshold;

[0052] S103 plans an autonomous driving path using the second threshold as a hard constraint, and calculates a key state for current stability determination;

[0053] S104 compares the stability to determine whether the key state exceeds the stability triggering first threshold, if not, proceed to S108; if so, proceed to S105;

[0054] S105 determines whether the stability exceeds the second threshold. If so, the process proceeds to S106. If not, the process proceeds to S107.

[0055] S106 activates the vehicle stability control algorithm and controls the chassis actuators;

[0056] S107 determines whether the path tracking error and vehicle stability trend are safe. If they are within the safe range, the process proceeds to S108; if not, the process proceeds to S106.

[0057] S108 performs chassis fusion control with the second stability threshold as a soft constraint, and ultimately controls the chassis actuator.

[0058] In one embodiment of the present invention, the autonomous driving path tracking and vehicle stability control collaboration method of the present invention can determine whether the vehicle is in autonomous driving mode or manual driving mode based on the driving mode judgment module; when the vehicle is in manual driving mode, the vehicle stability control module and the chassis fusion control module control the vehicle's driving action based on the driver's intention recognition; when the vehicle is in autonomous driving mode, the autonomous driving module, the extreme working condition extended control safety judgment module, the vehicle stability control module, the chassis fusion control module, etc. jointly control the vehicle's driving action.

[0059] In one embodiment of the present invention, when the vehicle is in manual driving mode, the vehicle stability control module includes: determining whether to activate the vehicle stability control algorithm based on the vehicle stability determination key state and the stability trigger first threshold; if the stability determination key state exceeds the stability trigger first threshold, activating the vehicle stability control algorithm to control the vehicle's movement according to the driver's intention and ideal steering characteristics; if the stability determination key state does not exceed the stability trigger first threshold, the chassis fusion control module allocates chassis actuator control commands based on the driver's intention, comprehensively considering vehicle movement safety, economy, comfort and other goals, and controls the vehicle's movement.

[0060] In one embodiment of the present invention, the key state for determining stability includes one or more combinations of information such as yaw rate, sideslip angle of the center of mass, vehicle speed, wheel speed, and road adhesion, which can be obtained through theoretical deduction or experimental calibration.

[0061] In one embodiment of the present invention, when the vehicle is in automatic driving mode, the automatic driving module includes: the automatic driving module receives the stability trigger second threshold sent by the stability control module, uses the stability trigger second threshold as a hard constraint (cannot be violated or exceeded), combines the traffic environment, dynamically adjusts the planned path, and sends the planned path to the chassis fusion control module.

[0062] In one embodiment of the present invention, the extreme working condition extended control safety judgment module of the automatic driving mode includes: combining vehicle status information such as the current vehicle speed and wheel speed, when the key stability judgment state such as the vehicle yaw angular velocity is less than the first stability trigger threshold of the current vehicle state, the vehicle stability control module is not activated; when the key stability judgment state such as the vehicle yaw angular velocity exceeds the original stability trigger threshold under the current vehicle state and is less than the second stability trigger threshold under the current vehicle state, it is judged whether the path tracking error and the vehicle stability trend at the current moment are within the safety range, if so, the vehicle stability control module is not activated, otherwise the vehicle stability control module is activated; when the key stability judgment state such as the vehicle yaw angular velocity exceeds the second stability trigger threshold under the current vehicle state, the vehicle stability control module is activated.

[0063] In one embodiment of the present invention, the key state for determining stability includes one or more combinations of information such as yaw rate, sideslip angle of the center of mass, vehicle speed, wheel speed, and road adhesion, which can be obtained through theoretical deduction or experimental calibration.

[0064] In one embodiment of the present invention, whether the current moment path tracking error and vehicle stability trend of the extreme working condition extended control safety judgment module are within the safety range includes: if the deviation between the current actual path of the vehicle and the automatic driving planned path is less than the trajectory allowable deviation threshold, and the time exceeding the stability trigger threshold is less than the trajectory allowable deviation threshold, then it is within the safety range, otherwise it is in the unsafe range; the trajectory allowable deviation threshold and the trajectory allowable deviation threshold can be obtained by theoretical deduction or experimental calibration.

[0065] In one embodiment of the present invention, the vehicle stability control module of the automatic driving mode includes: the vehicle stability control module sends a stability trigger second threshold to the automatic driving module, and sends a stability trigger first threshold to the chassis fusion control module; when the stability control module is activated, the vehicle stability control algorithm is called, and the actuator command is sent directly to the chassis actuator.

[0066] In one embodiment of the present invention, the chassis fusion control module of the automatic driving mode includes: the chassis fusion control module receives a first stability trigger threshold and sets it as a soft constraint (allowing short-term violation or exceeding); when the stability control module is not activated, it receives the driving path planned by the automatic driving, and performs motion control and execution control optimization allocation in combination with the soft constraints to control the movement of the vehicle; when the stability control module is activated, it locally adjusts the driving path based on the received automatic driving plan, and assists the stability control module in maintaining the stability of the vehicle posture until the stability control algorithm exits.

[0067] With the improvement and application of autonomous driving levels, the problems solved by this method and system will gradually become apparent, providing solutions for subsequent industrial applications, greatly improving the driving safety performance of autonomous driving vehicles, and having strong implementation and application prospects.

[0068] The collaborative method for autonomous driving path tracking and vehicle stability control, according to an embodiment of the present invention, considers the coordination between path planning and vehicle stability control in autonomous driving mode. This approach, while limiting autonomous driving path planning to paths that could lead to severe vehicle instability, also expands the range of motion control available for path planning compared to traditional conservative stability control, ensuring that it is triggered only in extremely severe instability situations. This combination enhances the autonomous driving motion control capability under extreme conditions, reduces or even minimizes the number of autonomous driving exits caused by stability control triggering, and improves vehicle motion safety.

[0069] To implement the above embodiment, this embodiment further provides an autonomous driving path tracking and vehicle stability control collaborative system, including:

[0070] A driving mode judgment module is used to judge whether the vehicle is in manual driving mode or automatic driving mode;

[0071] Autonomous driving module, used to plan autonomous driving paths;

[0072] The extreme operating condition extended control safety judgment module is used to monitor whether the vehicle is in a controllable motion range in autonomous driving mode and activate vehicle stability control before serious instability occurs;

[0073] Vehicle stability control module, used to call vehicle stability control algorithm in manual driving mode and automatic driving mode;

[0074] The chassis fusion control module is used to distribute chassis actuator control commands and control the vehicle's movement in manual driving mode. In automatic driving mode, it constrains motion control and optimizes distributed execution control when stability control is not activated. When stability control is activated, it assists stability control to maintain the stability of the vehicle's posture.

[0075] Specifically, Figure 2 This is a schematic diagram of the collaborative system of autonomous driving path tracking and vehicle stability control according to the present invention. Under the judgment of the driving mode determination module 201, in manual driving mode, the driver 301 receives environmental information 300 and manipulates the control mechanism 302. The vehicle stability control module 204 and the chassis fusion control module 205 recognize the driver's intention and control the actuator 303 to achieve motion control of the vehicle 304. In autonomous driving mode, the autonomous driving module 202 receives environmental information 300 and collaborates with the vehicle stability control module 204 to plan a safe path. The extreme operating condition extended control safety determination module 204 and the chassis fusion control module 205 collaborate to expand the controllable chassis motion range, control the actuator 303, and implement motion control of the vehicle 304. Under unavoidable severe instability conditions, the extreme operating condition extended control safety determination module 204 and the vehicle stability control module 205 collaborate to implement the stability algorithm and control the actuator 303 to achieve motion control of the vehicle 304.

[0076] The automatic driving path tracking and vehicle stability control cooperation system according to the embodiment of the present application considers the cooperation problem of path planning and vehicle stability control in the automatic driving mode, on the one hand, limits the automatic driving path planning to cause the path of the vehicle serious instability, and on the other hand, compared with the traditional conservative stability control, the motion control interval available for path planning is expanded, and the stability is triggered only in the case of extreme serious instability. Combination of the two, improve the automatic driving motion control limit working condition control ability, reduce or even reduce the automatic driving exit caused by stability control trigger, improve the vehicle motion safety performance.

[0077] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, a person skilled in the art can combine and combine different embodiments or examples described in the present specification and the features of different embodiments or examples without contradiction.

[0078] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

Claims

1. A method for coordinating autonomous driving path tracking and vehicle stability control, characterized in that: include: S100 identifies vehicle driving mode; S101 determines whether to enter the automatic driving mode; if it is identified as the manual driving mode, enter S109; if it is identified as the automatic driving mode, enter S102; S109 performs driver intention analysis; S110 calculates key states for determining vehicle stability; S111 determines whether the critical state exceeds the first stability trigger threshold in the current state; If the stability triggering first threshold is exceeded, the process proceeds to S112; If the stability triggering first threshold is not exceeded, the process proceeds to S113; S112 activates the vehicle stability control algorithm and controls the chassis actuators; S113 activates chassis fusion control to optimize the distribution of actuators and finally controls the chassis actuators for control; S102 receives a current state stability triggering second threshold; S103 plans an autonomous driving path using the second threshold as a hard constraint, and calculates a key state for current stability determination; S104 compares the stability to determine whether the key state exceeds the stability triggering first threshold, if not, proceed to S108; if so, proceed to S105; S105 determines whether the stability triggering second threshold is exceeded. If it exceeds the second threshold, the process proceeds to S106. If it does not exceed the second threshold, the process proceeds to S107. S106 activates the vehicle stability control algorithm and controls the chassis actuators; S107 determines whether the path tracking error and vehicle stability trend are safe. If they are within the safe range, the process proceeds to S108; if not, the process proceeds to S106. S108 triggers chassis fusion control with the second stability threshold as a soft constraint, and ultimately controls the chassis actuator.

2. The method according to claim 1, characterized in that When the vehicle is in manual driving mode, determining whether to activate a vehicle stability control algorithm based on a vehicle stability determination critical state and a stability triggering first threshold value, activating the vehicle stability control algorithm to control vehicle motion based on driver intent and ideal steering characteristics if the stability determination critical state exceeds the stability triggering first threshold value; and allocating chassis actuator control commands based on driver intent to control vehicle motion if the stability determination critical state does not exceed the stability triggering first threshold value. When the vehicle is in the automatic driving mode, it receives the stability triggering second threshold, uses the stability triggering second threshold as a hard constraint, and dynamically adjusts the planned path.

3. The method according to claim 1, characterized in that Based on the vehicle state information, when the vehicle stability determination key state is less than a first stability trigger threshold of the current vehicle state, the vehicle stability control program is not activated; when the stability determination key state exceeds the first stability trigger threshold of the current vehicle state and is less than a second stability trigger threshold of the current vehicle state, it is determined whether the path tracking error and the vehicle stability trend at the current moment are within a safe range. If so, the vehicle stability control program is not activated; if not, the vehicle stability control program is activated; When the key stability determination state such as the vehicle yaw rate exceeds the stability triggering second threshold under the current vehicle state, the vehicle stability control program is activated.

4. The method according to claim 3, characterized in that Whether the path tracking error and vehicle stability trend at the current moment are within a safe range includes: If the deviation between the current vehicle's actual path and the autonomous driving planned path is less than the trajectory tolerance threshold, and the time exceeding the stability triggering second threshold is less than the trajectory tolerance threshold, then it is within the safe range, otherwise it is in the unsafe range.

5. The method according to claim 1, wherein The key state for determining vehicle stability includes: one or more combinations of yaw rate, sideslip angle of center of mass, vehicle speed, wheel speed, and road adhesion information.

6. The method according to claim 1, characterized in that The chassis fusion control system receives the first stability trigger threshold and sets it as a soft constraint; when the stability control program is not activated, it receives the driving path planned by the autonomous driving, and combines the soft constraints to perform motion control and execution control optimization allocation to control the movement of the vehicle; when the stability control program is activated, based on the received driving path planned by the autonomous driving, it locally adjusts the driving path to help maintain the stability of the vehicle posture until the stability control algorithm exits.

7. An autonomous driving path tracking and vehicle stability control collaborative system using the method according to claim 1, characterized in that: include: A driving mode judgment module is used to judge whether the vehicle is in manual driving mode or automatic driving mode; Autonomous driving module, used to plan autonomous driving paths; The extreme operating condition extended control safety judgment module is used to monitor whether the vehicle is in a controllable motion range in autonomous driving mode and activate vehicle stability control before serious instability occurs; Vehicle stability control module, used to call vehicle stability control algorithm in manual driving mode and automatic driving mode; The chassis fusion control module is used to distribute chassis actuator control commands and control the vehicle's movement in manual driving mode. In automatic driving mode, it constrains motion control and optimizes distributed execution control when stability control is not activated. When stability control is activated, it assists stability control to maintain the stability of the vehicle's posture.

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