Yawing moment control method integrating multi-mode state machine and grading pressure control

Abstract

The invention discloses an active yaw moment control method integrating a multi-mode state machine and graded pressure control, and relates to the technical field of vehicle dynamics control. The method aims at solving the problems that a traditional vehicle yaw control system is lagged in yaw velocity dynamic response, insufficient in torque distribution and brake pressure control collaboration, limited in control precision and lack of personalized adaptation. The core of the system is to construct a multi-modal state machine framework, and realize accurate yaw control of the vehicle under different working conditions by combining a dynamic torque control algorithm, hierarchical brake pressure control and road adhesion coefficient self-adaption, and meanwhile, the system supports a driver to autonomously select a driving style, and improves driving safety and personalized experience.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle control, in particular to a yaw moment control method integrating multi-modal state machine and hierarchical pressure control. BACKGROUND

[0002] The conventional vehicle yaw control system usually adopts a single feedback mechanism, which monitors the yaw angular velocity, vehicle speed, steering angle and other parameters of the vehicle, and adjusts the yaw moment of the vehicle by using a proportional-integral-derivative (PID) controller to realize the yaw stability control of the vehicle. Meanwhile, in the research of modern vehicle dynamics characteristics, researchers pay more and more attention to the difference of individual needs of different drivers, and formulate corresponding control strategies according to the individual needs of different drivers, so as to improve their own driving experience. The focus of the optimization of the relationship between man and vehicle has shifted from meeting the common needs of ordinary drivers to focusing on the special needs of each individual driver. If the vehicle control is only implemented in extreme conditions, not only the dynamics performance will be wasted, but also the vehicle dynamics characteristics will be difficult to meet the individual needs of different drivers. At present, there is a lack of individual lateral stability control strategy considering driving style. SUMMARY

[0003] The present application aims to solve at least one of the technical problems existing in the prior art, and provides a yaw moment control method integrating multi-modal state machine and hierarchical pressure control.

[0004] In a first aspect, an embodiment of the present application provides a yaw moment control method integrating multi-modal state machine and hierarchical pressure control, comprising:

[0005] determining a vehicle stability factor according to the driving style type of the driver, and obtaining a vehicle reference yaw angular velocity based on the vehicle stability factor;

[0006] constructing a vehicle multi-modal state machine based on the vehicle reference yaw angular velocity and the current vehicle real-time yaw angular velocity;

[0007] determining a current dynamic torque control mode according to the steering wheel angular velocity, and performing dynamic torque control according to the current dynamic torque control mode;

[0008] dividing the active rear axle torque control state into multiple states according to the constructed multi-modal state machine, obtaining the duty cycles of the pressure increasing valve and the pressure limiting valve according to the multiple states, and controlling the pressure of the vehicle wheel cylinder.

[0009] Further, the vehicle stability factor is determined according to the driving style type of the driver, and a vehicle reference yaw rate is obtained based on the vehicle stability factor, and the specific steps include: obtaining the driving style type of the driver through a vehicle-mounted interactive system or a control interface, including at least a sporty type, a comfortable type or an economical type; converting the driving style into a vehicle stability factor according to a preset mapping relationship or an empirical formula, and then calculating a driving style gain coefficient through a specific algorithm or a lookup table method; the gain coefficient is used to adjust the parameter weight of the control system, and then applied to the yaw rate calculation formula of the vehicle dynamics model to obtain the reference yaw rate.

[0010] Further, a vehicle multi-modal state machine is constructed based on the vehicle reference yaw rate and the current vehicle real-time yaw rate, and the vehicle multi-modal state machine includes at least an inactive state, a left turn insufficient front wheel control state, a right turn insufficient front wheel control state, a left turn excessive rear wheel differential control state, and a right turn excessive rear wheel differential control state.

[0011] Further, a hierarchical condition judgment method is used to judge the switching priority of the vehicle multi-modal state machine, and the specific steps include: taking steering over as the first priority, taking steering insufficient as the second priority, and taking the inactive state as the third priority; in the state switching process, if multiple conditions are met at the same time, the historical state duration and the sensor confidence are used for weighted decision.

[0012] Further, a current dynamic torque control mode is determined according to the steering wheel angle rate, and the dynamic torque control mode includes a normal mode and an emergency mode, wherein when the steering wheel angle rate is less than or equal to 300° / s, the dynamic torque control mode is the normal mode, and when the steering wheel angle rate is greater than 300° / s, the dynamic torque control mode is the emergency mode.

[0013] Further, dynamic torque control is performed according to the current dynamic torque control mode, and the specific steps include: when the dynamic torque control mode is the normal mode, a standard PID algorithm is used to accurately control the torque through proportional, integral and differential links, so as to ensure that the yaw rate is stably within the target range; when the dynamic torque control mode is the emergency mode, the standard PID algorithm is switched to a fuzzy PID algorithm and the differential weight is increased, so as to quickly respond to the driver's operation and suppress the rapid change of the yaw rate.

[0014] Further, when the dynamic torque control is performed, the torque control needs to be limited, and the specific limitations include a basic limitation and a driver intention limitation, wherein the basic limitation is a torque lower limit set according to the physical performance of the vehicle and safety standards, to ensure the basic safety of the vehicle operation; the driver intention limitation is to adjust the torque according to the accelerator pedal position, the vehicle speed information and the driving style of the driver, so that the vehicle response is more in line with the driver's expectation.

[0015] Further, when the dynamic torque control is performed, an exiting torque control strategy is also performed, and the specific process includes: gradually reducing the control torque increment, so that the engine torque is smoothly transitioned to the driver demand torque; and monitoring the vehicle state, so that the vehicle yaw rate dynamic parameter is kept stable during the exiting process, and vehicle dynamic abnormality caused by control exiting is avoided.

[0016] Further, according to the constructed multi-modal state machine, the active rear axle torque control state is divided into multiple states, and the multiple states at least include: a steady-state around circle state, a non-boosting state, a yaw acceleration deviation increasing state under insufficient steering, a yaw acceleration deviation stable state under insufficient steering, a yaw acceleration deviation decreasing state under insufficient steering, a yaw acceleration deviation increasing state under excessive steering, a yaw acceleration deviation stable state under excessive steering, and a yaw acceleration deviation decreasing state under excessive steering.

[0017] Further, the multiple states are switched according to the wheel slip rate, the wheel acceleration and the adhesion coefficient, and whether the condition for exiting the pre-boosting is met is determined in real time according to the wheel slip rate, the wheel acceleration and the road adhesion coefficient; wherein the estimation method of the road adhesion coefficient includes: through real-time collection of vehicle driving data such as wheel speed, yaw rate, longitudinal acceleration, a statistical method and a vehicle dynamics model are used to estimate the adhesion coefficient of the current road.

[0018] In a second aspect, the present application further discloses an electronic device, comprising:

[0019] one or more processors;

[0020] a memory for storing one or more programs;

[0021] When the one or more programs are executed by the one or more processors, the one or more processors implement the yaw moment control method.

[0022] In a third aspect, a computer readable medium, the computer readable medium stores a computer program, and the computer program is executed by a processor to implement the steps in the yaw moment control method.

[0023] The application discloses an active yaw moment control method integrating a multi-modal state machine and hierarchical pressure control, which aims to solve the problems of dynamic response lag of yaw angle speed of a traditional vehicle yaw control system, insufficient coordination of torque distribution and brake pressure control, limited control precision and lack of personalized adaptation. The core is to build a multi-modal state machine architecture, combine a dynamic torque control algorithm, hierarchical brake pressure control and road adhesion coefficient self-adaptation, realize accurate yaw control of the vehicle under different working conditions, support autonomous selection of driving style by the driver, and improve driving safety and personalized experience. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 A flowchart of a yaw moment control method integrating a multi-modal state machine and hierarchical pressure control is provided for the embodiment of the application.

[0025] Figure 2 A flowchart of a multi-modal state machine architecture construction method is provided for the embodiment of the application.

[0026] Figure 3 A flowchart of a hierarchical brake pressure control method is provided for the embodiment of the application.

[0027] Figure 4 A structural block diagram of an electronic device is provided for the embodiment of the application. DETAILED DESCRIPTION

[0028] In order for those skilled in the art to better understand the technical solutions of the present application, the following describes exemplary embodiments of the present application in conjunction with the accompanying drawings, including various details of the embodiments of the present application to help understanding, which should be considered only as exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Also, for the sake of clarity and conciseness, the description below omits the description of well-known functions and structures.

[0029] In the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0030] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0031] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. "Coupled" or "connected" or similar terms are not restricted to physical or mechanical connections or associations, but can also include electrical connections, whether direct or indirect.

[0032] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an overly literal or overly formal sense unless expressly so defined herein.

[0033] In the technical solutions of the present application, the collection, storage, use, processing, transmission, provision and disclosure of user personal information comply with relevant laws and regulations and do not violate public order and good customs. The use of user data in the technical solutions complies with relevant national laws and regulations (for example, "Information Security Technology Personal Information Security Specification" and the like). For example, appropriate measures are taken for personal information access control; the display of personal information is limited as specified; the use purpose of personal information does not exceed the direct or reasonably related range; and the use of personal information eliminates explicit identity pointing and avoids precise positioning to a specific individual.

[0034] In the related art, the existing technology has obvious deficiencies. Taking the Bosch active yaw control function as an example, firstly, the dynamic response of the yaw angular velocity is lagging, which cannot adapt to complex road conditions; secondly, the coordination between torque distribution and brake pressure control is insufficient; and thirdly, there is a lack of user autonomy, and the driving style cannot be selected according to personal preferences and actual needs. In addition, if vehicle control is only implemented in extreme working conditions, not only the dynamic performance will be wasted, but also the overall vehicle dynamics characteristics will be difficult to match the individualized needs of different drivers. There is currently a lack of individualized lateral stability control strategies that take driving style into account.

[0035] To solve at least one of the technical problems existing in the related art, the present application provides an active yaw moment control method integrating a multi-modal state machine and a hierarchical pressure control.

[0036] The active yaw moment control method integrating a multi-modal state machine and a hierarchical pressure control provided by the embodiments of the present application is as follows: Figure 1, comprising:

[0037] S100. determining a vehicle stability factor according to the driver driving style type, and obtaining a vehicle reference yaw rate based on the vehicle stability factor;

[0038] In this embodiment, a vehicle stability factor is determined according to the driver driving style type, and a vehicle reference yaw rate is obtained based on the vehicle stability factor. The specific steps include: obtaining the driver's driving style type through a vehicle-mounted interactive system or a control interface, including at least sporty, comfortable or economical; converting the driving style into a vehicle stability factor according to a preset mapping relationship or an empirical formula, and calculating a driving style gain coefficient through a specific algorithm or a lookup table method; the gain coefficient is used to adjust the control system parameter weight, and then applied to the yaw rate calculation formula of the vehicle dynamics model to obtain the reference yaw rate.

[0039] Specifically, 2. The driver can select the appropriate driving style, such as sporty, comfortable or economical, through the vehicle-mounted interactive system or the control interface according to his own preference and driving habit. The system determines the corresponding vehicle stability factor according to the driving style selected by the driver, and references the pre-set mapping relationship or the empirical formula to quantify the stability characteristics of the vehicle under the current driving style. Based on the vehicle stability factor, a driving style gain coefficient is calculated through a specific algorithm or a lookup table method. The coefficient is used to adjust the weight of some parameters in the vehicle control system to adapt to the control requirements under different driving styles. The driving style gain coefficient is applied to the yaw rate calculation formula in the vehicle dynamics model to obtain the reference yaw rate. The state transition is dynamically determined by the difference between the yaw rate and the expected yaw rate and the gradient of the difference. The change trend of the vehicle steering state is comprehensively judged by the difference between the current yaw rate and the expected yaw rate calculated based on the vehicle speed, steering angle, etc., and the change rate (gradient) of the difference, so as to trigger the state switching.

[0040] S200. constructing a vehicle multi-modal state machine based on the vehicle reference yaw rate and the current vehicle real-time yaw rate;

[0041] In this embodiment, a vehicle multi-modal state machine is constructed based on the vehicle reference yaw rate and the current vehicle real-time yaw rate. The vehicle multi-modal state machine includes at least a non-activated state, a left turn insufficient front wheel control state, a right turn insufficient front wheel control state, a left turn excessive rear wheel differential control state, and a right turn excessive rear wheel differential control state.

[0042] In some preferred embodiments, a hierarchical conditional judgment method is used to judge the switching priority of the vehicle multi-modal state machine, such as Figure 2Specifically, the over-steering is taken as a first priority, the under-steering is taken as a second priority, and the inactivation is taken as a third priority; in the state switching process, if multiple conditions are met simultaneously, a decision is made based on a historical state duration and a sensor confidence.

[0043] S300. Determining a current dynamic torque control mode according to a steering wheel angular rate, and performing dynamic torque control according to the current dynamic torque control mode.

[0044] In the embodiment, the current dynamic torque control mode is determined according to the steering wheel angular rate, and the dynamic torque control mode includes a normal mode and an emergency mode, wherein when the steering wheel angular rate is less than or equal to 300° / s, the dynamic torque control mode is the normal mode, and when the steering wheel angular rate is greater than 300° / s, the dynamic torque control mode is the emergency mode.

[0045] In the embodiment, the dynamic torque control is performed according to the current dynamic torque control mode, and the specific steps include: when the dynamic torque control mode is the normal mode, a standard PID algorithm is used to accurately control the torque through proportional, integral, and differential links to ensure that the yaw rate is stable in the target range; when the dynamic torque control mode is the emergency mode, the standard PID algorithm is switched to a fuzzy PID algorithm and the differential weight is increased to quickly respond to the driver's operation, suppress the rapid change of the yaw rate, and use the fuzzy PID control strategy to enhance the role of the differential link to adjust the torque output more timely.

[0046] In the embodiment, when the dynamic torque control is performed, the torque control needs to be limited, and the specific limitations include a basic limitation and a driver intention limitation, wherein the basic limitation is a torque lower limit set according to the vehicle physical performance and safety standards to ensure the basic operation safety of the vehicle; the driver intention limitation is to adjust the torque according to the accelerator pedal position, vehicle speed information, and driving style of the driver to make the vehicle response more in line with the driver's expectation and meet the driving habit.

[0047] In the embodiment, when the dynamic torque control is performed, an exit torque control strategy is also executed, and the specific process includes: gradually reducing the control torque increment to smoothly transition the engine torque to the driver demand torque; and monitoring the vehicle state to ensure that the vehicle yaw rate dynamic parameters remain stable during the exit process to avoid vehicle dynamic abnormalities caused by control exit.

[0048] S400. According to the constructed multi-modal state machine, the active rear axle torque control state is divided into multiple states, the duty cycles of the supercharging valve and the pressure limiting valve are obtained according to the multiple states, and the vehicle wheel cylinder pressure is controlled.

[0049] In this embodiment, according to the constructed multi-modal state machine, the active rear axle torque control state is divided into multiple states, such as Figure 3 , which at least include: 1. steady-state circular state, 2. no boost state, 3. under-steer condition lateral acceleration deviation increasing state, 4. under-steer condition lateral acceleration deviation stable state, 5. under-steer condition lateral acceleration deviation decreasing state, 6. over-steer condition lateral acceleration deviation increasing state, 7. over-steer condition lateral angular velocity deviation stable state, and 8. over-steer condition lateral angular velocity deviation decreasing state.

[0050] In this embodiment, according to the wheel slip rate, wheel acceleration and adhesion coefficient and other parameters, it is judged in real time whether the condition for exiting the pre-boost is met. For example, under ice conditions, when the wheel slip rate exceeds a certain threshold and the wheel acceleration is less than a set value, the pre-boost stage is exited to avoid excessive braking causing wheel lock; under snow conditions, considering factors such as wheel slip rate, wheel acceleration and braking time, the exit timing is flexibly adjusted.

[0051] Among them, the road adhesion coefficient is calculated by using an adaptive algorithm, which specifically includes: 1. classification threshold: ice: adhesion coefficient < 20; snow: 20 ≤ adhesion coefficient ≤ 60; high adhesion road: adhesion coefficient > 60. By collecting vehicle driving data such as wheel speed, lateral angular velocity, longitudinal acceleration, etc. in real time, the adhesion coefficient of the current road is estimated by using statistical methods and vehicle dynamics model, and is classified according to the preset threshold, providing a basis for subsequent control parameter adjustment.

[0052] The present embodiment also controls the dynamic adjustment of the parameters, and the under-steer exit threshold changes with the adhesion coefficient. According to the vehicle dynamics characteristics under different adhesion coefficients, the under-steer exit judgment threshold is dynamically adjusted. On low adhesion coefficient road, the exit threshold is appropriately relaxed to avoid false exit caused by poor road conditions; on high adhesion coefficient road, the exit threshold is tightened to ensure accurate control of vehicle steering performance.

[0053] The embodiment discloses an active yaw moment control method integrating multi-modal state machine and hierarchical pressure control, which aims to solve the problems of traditional vehicle yaw control system, such as yaw angular velocity dynamic response lag, insufficient coordination between torque distribution and brake pressure control, limited control accuracy and lack of personalized adaptation. The core is to construct a multi-modal state machine architecture, combined with dynamic torque control algorithm, hierarchical brake pressure control and adaptive road adhesion coefficient, to realize accurate yaw control of the vehicle under different working conditions, while supporting the driver to choose the driving style independently, improving the driving safety and personalized experience.

[0054] In order to better understand the present embodiment, the present disclosure describes the above method with specific examples. For example:

[0055] 1. System initialization: After the vehicle starts, the system enters the non-activated state ST_AYC_NA, initializes the yaw rate sensor, wheel speed sensor, steering angle sensor and other devices, collects initial vehicle speed, steering angle and other parameters, sets the default driving style as comfortable, calculates the initial vehicle stability factor and driving style gain coefficient.

[0056] 2. Driving style selection and parameter configuration: The driver selects the sporty driving style through the vehicle-mounted central control screen, and the system adjusts the vehicle stability factor corresponding to the sporty style to 1.2 (the default is 1.0 for comfortable type) according to the preset mapping relationship, and then calculates the driving style gain coefficient as 1.1 through table lookup method, which is applied to the yaw rate calculation formula to obtain the reference yaw rate.

[0057] 3. State monitoring and switching: When the vehicle is driving on a curve, the sensor real-time collects the yaw rate as 5° / s, the expected yaw rate as 4.5° / s, the difference as 0.5° / s, and the difference gradient as 0.2° / s². The system determines that it is a left turn overstate, and triggers the state switching from the non-activated state ST_AYC_NA to the left turn overstate rear wheel differential control ST_AYC_TL_OVER_RDWC.

[0058] 4. Dynamic torque control execution: At this time, the steering wheel angle rate is 350° / s, the system switches to fuzzy PID control, increases the derivative weight to 0.8 (the standard PID derivative weight is 0.5), and calculates the target torque as 150 N m. At the same time, the basic limit layer sets the torque lower limit as 50 N m, the driver's intention layer combines the throttle pedal position (50% opening) and the vehicle speed (60 km / h), and finally outputs the torque 140 N m, and adjusts the rear wheel differential torque.

[0059] 5. Graded brake pressure control: The system determines that the AYC control state is "yaw rate deviation increases under excessive steering condition" according to the yaw rate difference and gradient, calculates the boost valve duty ratio as 60%, the pressure limiting valve duty ratio as 30%, adjusts the left rear wheel cylinder pressure to 1.8 MPa, and the right rear wheel cylinder pressure to 1.2 MPa, to suppress excessive steering.

[0060] 6. Road adhesion coefficient adaptive adjustment: The sensor collects wheel speed and longitudinal acceleration data to estimate the current road adhesion coefficient as 35, which is determined as snow surface. The system adjusts the understeering exit threshold from 0.3° / s on high adhesion road to 0.5° / s to avoid false exit control.

[0061] 7. Control Exit: After the vehicle exits the curve, the yaw rate returns to 4.5° / s, with a difference of 0. The system executes the torque release logic, gradually reducing the control torque increment from 50 N·m to 0. The engine torque smoothly transitions to the driver's required 120 N·m. At the same time, the wheel cylinder pressure returns to the normal level, and the system returns to the inactive state ST_AYC_NA.

[0062] The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should be included within the scope of protection defined by the claims of the present invention.

[0063] Based on the same inventive concept, embodiments of the present invention also provide an electronic device. Figure 4 This is a structural block diagram of an electronic device provided in an embodiment of the present invention. Figure 4 As shown, an embodiment of the present invention provides an electronic device including: one or more processors 101, a memory 102, and one or more I / O interfaces 103. The memory 102 stores one or more programs, which, when executed by the one or more processors, cause the one or more processors to implement any of the yaw torque control methods described in the above embodiments; the one or more I / O interfaces 103 are connected between the processor and the memory, configured to enable information interaction between the processor and the memory.

[0064] The processor 101 is a device with data processing capabilities, including but not limited to a central processing unit (CPU); the memory 102 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and flash memory (FLASH); the I / O interface (read / write interface) 103 is connected between the processor 101 and the memory 102, and can realize information interaction between the processor 101 and the memory 102, including but not limited to a data bus (Bus).

[0065] In some embodiments, the processor 101, memory 102, and I / O interface 103 are interconnected via bus 104, and thus connected to other components of the computing device.

[0066] In some embodiments, the one or more processors 101 include a field-programmable gate array.

[0067] The embodiment of the present application also provides a computer readable medium. The computer readable medium stores a computer program, wherein the program is executed by a processor to implement the steps in the yaw moment control method in any of the above embodiments. The computer readable storage medium can be a volatile or non-volatile computer readable storage medium.

[0068] The embodiment of the present application also provides a computer program product comprising computer readable code or a non-volatile computer readable storage medium carrying computer readable code, when the computer readable code is run in a processor of an electronic device, the processor in the electronic device executes the above yaw moment control method.

[0069] Those skilled in the art can understand that all or some of the steps in the above disclosed method, the functions of the modules / units in the system and the device can be implemented as software, firmware, hardware and appropriate combinations thereof. In the hardware implementation, the division between the functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, one physical component can have multiple functions, or one function or step can be performed by several physical components in cooperation. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor or a microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software can be distributed on a computer readable storage medium, which can include computer storage media (or non-transitory media) and communication media (or transitory media).

[0070] As known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable program instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM), static random access memory (SRAM), flash memory or other memory technology, portable compact disc read only memory (CD-ROM), digital versatile disc (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. In addition, it is known to those skilled in the art that communication media typically includes computer readable program instructions, data structures, program modules or other data in modulated data signals such as carrier waves or other transport mechanisms, and can include any information delivery medium.

[0071] The computer readable program instructions described herein can be downloaded to respective computing / processing devices from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and / or a wireless network. The network can comprise copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers and / or edge servers. A network adapter card or network interface in each computing / processing device receives computer readable program instructions from the network and forwards the computer readable program instructions for storage in a computer readable storage medium within the respective computing / processing device.

[0072] Computer readable program instructions for carrying out operations of the present application can be assembler instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, or either source code or object code written in any combination of one or more programming languages, including an object oriented programming language such as Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program instructions can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider). In some embodiments, electronic circuitry including, for example, programmable logic circuitry, field-programmable gate array (FPGA), or programmable logic array (PLA) can execute the computer readable program instructions by utilizing state information of the computer readable program instructions to personalize the electronic circuitry, in order to perform aspects of the present application.

[0073] The computer program product described herein can be embodied specifically by hardware, software or a combination thereof. In one alternative embodiment, the computer program product is embodied specifically as a computer storage medium, and in another alternative embodiment, the computer program product is embodied specifically as a software product, such as a software development kit (SDK) or the like.

[0074] The computer program product described herein can be embodied specifically by hardware, software or a combination thereof. In one alternative embodiment, the computer program product is embodied specifically as a computer storage medium, and in another alternative embodiment, the computer program product is embodied specifically as a software product, such as a software development kit (SDK) or the like.

[0075] These computer readable program instructions can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks. These computer readable program instructions can also be stored in a computer readable storage medium that can include a non-transitory computer readable storage medium that can be a computer- readable storage medium having no data storage cycles that change state. The instructions can be executed by one or more processors of a computer, other programmable data processing apparatus, or other devices to produce a computer-implemented process such that the instructions which execute via the one or more processors of the computer or other programmable data processing devices create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks. The computer program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0076] The computer readable program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other device to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0077] The flow diagrams and the block diagrams in the drawings are presented to illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to the present application. In this regard, each block in the flow diagrams and the block diagrams can represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical functions ("instructions"). In some alternative implementations, the functions noted in the blocks can occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks can sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and / or flow diagrams, and combinations thereof, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and

[0078] Example embodiments have been disclosed herein and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation. In some instances, it will be apparent to those skilled in the art that features, characteristics or aspects described with reference to a particular embodiment can be used alone or in combination with other embodiments, unless expressly stated otherwise. Accordingly, it will be understood that various changes in form and details can be made without departing from the scope of the present application as set forth in the appended claims.

Claims

1. A yaw moment control method integrating a multi-modal state machine with hierarchical pressure control, characterized in that, The application relates to a vehicle stability control method and system. The vehicle stability factor is determined according to the driving style type of the driver, and the vehicle reference yaw rate is obtained based on the vehicle stability factor. The vehicle multi-mode state machine is constructed based on the vehicle reference yaw rate and the current vehicle real-time yaw rate. The current dynamic torque control mode is determined according to the steering wheel rotation rate, and the dynamic torque control is executed according to the current dynamic torque control mode. The active rear axle torque control state is divided into multiple states according to the constructed multi-mode state machine, the duty cycles of the supercharging valve and the pressure limiting valve are obtained according to the multiple states, and the vehicle wheel cylinder pressure is controlled.

2. The yaw moment control method according to claim 1, characterized by, The vehicle stability factor is determined according to the driving style type of the driver, and the vehicle reference yaw rate is obtained based on the vehicle stability factor. Specifically, the driving style type of the driver is acquired through a vehicle-mounted interactive system or a control interface, and at least includes a sport type, a comfort type or an economy type. The driving style is converted into the vehicle stability factor according to a preset mapping relationship or an empirical formula, and a driving style gain coefficient is calculated through a specific algorithm or a table lookup method. The gain coefficient is used for adjusting the parameter weight of a control system, and is then applied to a yaw rate calculation formula of a vehicle dynamics model to obtain the reference yaw rate.

3. The yaw moment control method according to claim 1, characterized by, The vehicle multi-mode state machine is constructed based on the vehicle reference yaw rate and the current vehicle real-time yaw rate. The vehicle multi-mode state machine at least includes an inactivation state, a left turn deficiency front wheel control state, a right turn deficiency front wheel control state, a left turn excess rear wheel differential control state and a right turn excess rear wheel differential control state.

4. The yaw moment control method according to claim 3, characterized by, The switching priority of the vehicle multi-mode state machine is judged by using a hierarchical condition judgment method. Specifically, steering excess is taken as the first priority, steering deficiency is taken as the second priority, and the inactivation state is taken as the third priority. In the state switching process, if multiple conditions are met simultaneously, the historical state duration and the sensor confidence are weighted to make a decision.

5. The yaw moment control method according to claim 1, characterized by, The current dynamic torque control mode is determined according to the steering wheel rotation rate. The dynamic torque control mode includes a normal mode and an emergency mode. When the steering wheel rotation rate is less than or equal to 300 DEG / s, the dynamic torque control mode is the normal mode. When the steering wheel rotation rate is greater than 300 DEG / s, the dynamic torque control mode is the emergency mode.

6. The yaw moment control method according to claim 5, characterized by The dynamic torque control is executed according to the current dynamic torque control mode. Specifically, when the dynamic torque control mode is the normal mode, a standard PID algorithm is used to accurately control the torque through proportional, integral and differential links, so that the yaw rate is stably controlled in a target range. When the dynamic torque control mode is the emergency mode, the standard PID algorithm is switched to a fuzzy PID algorithm and the differential weight is increased, so that the driver operation is quickly responded and the yaw rate is quickly changed.

7. The yaw moment control method according to claim 1, characterized by, In the execution of dynamic torque control, the torque control needs to be limited, including the basic limit and the driver intention limit, wherein the basic limit is the torque lower limit set according to the vehicle physical performance and safety standards, ensuring the basic operation safety of the vehicle; the driver intention limit is to adjust the torque according to the accelerator pedal position, vehicle speed information, and the driving style of the driver, so that the vehicle response is more in line with the driver's expectation.

8. The yaw moment control method according to claim 1, characterized by, In the execution of dynamic torque control, the torque control strategy is also executed, and the specific process includes: gradually reducing the control torque increment, so that the engine torque is smoothly transitioned to the driver demand torque; at the same time, the vehicle state is monitored to ensure that the vehicle yaw rate dynamic parameter remains stable during the exit process, avoiding vehicle dynamic abnormalities caused by control exit.

9. The yaw moment control method according to claim 1, characterized by, According to the constructed multi-modal state machine, the active rear axle torque control state is divided into multiple states, including at least: steady-state around circle state, no supercharging state, under-steering condition, lateral acceleration deviation increasing state, under-steering condition, lateral acceleration deviation stable state, under-steering condition, lateral acceleration deviation decreasing state, over-steering condition, lateral acceleration deviation increasing state, over-steering condition, lateral acceleration deviation stable state, and over-steering condition, lateral acceleration deviation decreasing state.

10. The yaw moment control method according to claim 1, characterized by, According to the wheel slip rate, wheel acceleration and adhesion coefficient, the multiple states are switched, and whether the condition for exiting the pre-supercharging is met is determined in real time according to the wheel slip rate, wheel acceleration and road adhesion coefficient; wherein the estimation method of the road adhesion coefficient includes: through real-time acquisition of vehicle driving data such as wheel speed, yaw rate, longitudinal acceleration, statistical method and vehicle dynamics model are used to estimate the adhesion coefficient of the current road.

11. An electronic device, comprising: Comprise: One or more processors; Memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the yaw moment control method as claimed in any one of claims 1 to 10.

12. A computer readable medium having stored thereon a computer program, characterized in that The computer program is executed by the processor to implement the steps in the yaw moment control method as claimed in any one of claims 1 to 10.

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