Drive-by-wire chassis system and control method

Abstract

The invention discloses a drive-by-wire chassis system and a control method, the system comprises a drive-by-wire chassis controller, various wheel controllers, a hand feeling simulator, a steering actuator, a brake pedal sensor and a yaw velocity sensor, each wheel controller comprises an electronic mechanical brake and a wheel speed sensor, and when the steering actuator is completely or partially invalid, the steering actuator is switched on and switched off. And the drive-by-wire chassis controller can also calculate the yaw correction torque and the braking force of each wheel according to the state parameters of the vehicle to change the yaw angle of the vehicle so as to be matched with the steering request of the target angle of the steering wheel. On one hand, performance coupling of steering-by-wire and braking-by-wire of the chassis can be enhanced, so that accuracy and real-time performance of transverse control are improved; the control robustness of the response of the whole vehicle can be improved; on the other hand, when the steering actuator is completely or partially invalid, the yaw angle of the vehicle can meet the expectation input by a driver, power is supplied through a redundant power source, the system failure rate is reduced, and the redundant design cost is also reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicle chassis control, and in particular relates to a wire-controlled chassis system, and also relates to a control method for the wire-controlled chassis. Background Art

[0002] It is an inevitable trend for the automotive industry to shift its development focus from traditional internal combustion engines to new energy vehicles. New energy vehicles not only bring changes to the power system, but also put forward increasingly high wire-controlled requirements for the development of chassis technology to achieve the integration and intelligence of the entire chassis. Therefore, wire-controlled chassis is also a focus of development in the automotive industry, among which the core are the four major parts: braking, steering, suspension, and drive.

[0003] Currently, many drive-by-wire chassis system architectures integrate the control of the four core components mentioned above into the chassis domain controller for centralized processing. However, this presents the following difficulties:

[0004] 1) The internal calculation and communication cycles of the software of each component are not consistent, especially the strong correlation with the actuator. This operation method is not the best in terms of cost performance;

[0005] 2) From the perspective of functional safety, the requirements for braking and steering among the core components of the chassis are more stringent. The control accuracy and real-time responsiveness of the two are key indicators of the safety of the wire-controlled chassis. Therefore, from the perspective of the chassis wire-controlled system, it is urgent to find a control method that integrates steering and braking.

[0006] At the same time, in response to the above-mentioned difficulties, for example: CN202210757633.1 discloses a multi-source coupled skateboard chassis system and its collaborative control method, which mainly coordinates the drive, steering, braking and other systems, and includes an electro-hydraulic composite wire-controlled steering system and an electric composite braking system. The yaw moment calculation is established through a four-degree-of-freedom model, but does not involve fail-safe operations between systems; for example: CN202211027022.8 discloses a chassis component control device and method for a layered wire-controlled chassis system, which independently controls the functional modules through a chassis domain controller or actuator, but does not describe the control method of the specific system. In view of the disclosure of the above-mentioned documents, the development of the wire-controlled chassis urgently needs a cost-effective, simple and practical system architecture to promote the process of wire-controlled chassis integration. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide an improved wire-controlled chassis system.

[0008] At the same time, the present invention also relates to a control method of a wire-controlled chassis.

[0009] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0010] A drive-by-wire chassis system includes a drive-by-wire chassis controller, wheel controllers, a feel simulator, a steering actuator, a brake pedal sensor, and a yaw rate sensor, wherein each wheel controller includes an electronic mechanical brake and a wheel speed sensor, and the corresponding ones are a left front wheel controller, a left rear wheel controller, a right front wheel controller, and a right rear wheel controller. The feel simulator is connected to the steering wheel and converts the driver's steering request into a signal. The electronic mechanical brakes of the left front wheel controller and the right rear wheel controller are powered by a first power supply; the electronic mechanical brakes of the right front wheel controller and the left rear wheel controller are powered by a second power supply; the drive-by-wire chassis controller, the feel simulator, and the steering actuator are powered by a first power supply; the electronic mechanical brakes of the right front wheel controller and the left rear wheel controller are powered by a second power supply; the drive-by-wire chassis controller, the feel simulator, and the steering actuator are powered by a first power supply; the electronic mechanical brakes of the left front wheel controller and the right rear wheel controller are powered by a second power supply; the control circuit of ... The controllers are redundantly powered by the first and second power supplies. The drive-by-wire chassis controller receives signals from the first vehicle network, the second vehicle network, the brake pedal sensor, and the yaw rate sensor, and communicates with each electronic mechanical brake through the first private network and the second private network to send control instructions to each electronic mechanical brake, the feel simulator, and the steering actuator respectively. A communication channel is maintained between the feel simulator and the steering actuator. When the steering actuator fails completely or partially, the drive-by-wire chassis controller can also change the vehicle's yaw angle to match the steering request of the steering wheel target angle based on the yaw correction torque and the braking force of each wheel calculated according to the vehicle's state parameters.

[0011] In some specific embodiments, the by-wire chassis controller communicates with other vehicle components via a first vehicle network and a second vehicle network to facilitate process or remote control. Furthermore, the by-wire chassis controller utilizes redundant MCUs 1 and 2 for logic processing, reducing the failure rate of the by-wire chassis controller.

[0012] According to one specific implementation and preferred aspect of the present invention, a drive-by-wire chassis controller includes a yaw moment control module. The yaw moment control module receives a yaw angular rate signal, a steering wheel angle signal, a steering actuator status signal, and the right front, right rear, left front, and left rear wheel speed signals, and calculates and outputs a right front electromechanical braking torque request, a left front electromechanical braking torque request, a right rear electromechanical braking torque request, a left rear electromechanical braking torque request, and a drive torque request. In short, in the event of a complete or partial failure of the steering actuator, when the vehicle's steering wheels are unable to promptly respond to steering commands issued by the driver via the steering wheel angle, the yaw moment control module in the chassis controller proactively intervenes to improve the vehicle's lateral dynamics.

[0013] In some specific embodiments, the yaw moment control module receives the right front wheel speed signal, the right rear wheel speed signal, the left front wheel speed signal, and the left rear wheel speed signal, and calculates the reference vehicle speed v ref, the steering wheel angle input by the driver is δ, and the desired yaw rate γ tar It can be expressed as:

[0014]

[0015] Where l is the vehicle wheelbase, k(x) is a calibrated parameter, and is a two-dimensional curve associated with vehicle speed and steering wheel angle.

[0016] Preferably, the actual yaw rate signal γ act The yaw rate deviation γ is measured by the yaw rate sensor. err Equal to γ tar -γ act , the control target is 0.

[0017] In some embodiments, according to the front wheelbase T f and rear track T r , the obtained yaw correction torque dMz and the left front wheel braking force F fl , right front wheel braking force F fr , left rear wheel braking force F rl , the distribution of the right rear wheel braking force Frr is as follows:

[0018]

[0019] Among them F fl 、F fr 、F rl 、F rr Braking force and γ err In the case of steering actuator failure, the vehicle's yaw angle can meet the steering target angle request input by the driver; at the same time, when the reference vehicle speed v ref When the speed is lower than the threshold v0, the yaw moment control module sends a drive torque request to keep the vehicle speed at v0 in order to control the vehicle yaw angle. fl 、F fr 、F rl 、F rr Braking force and γ err The real-time relationship can adopt but is not limited to PID control strategy, and the ultimate goal is to ensure that the vehicle's yaw angle can meet the driver's input expectations when the steering actuator fails.

[0020] According to another specific implementation and preferred aspect of the present invention, the electronic mechanical brake includes an electronic mechanical brake controller, a brake motor, a transmission mechanism and a brake, wherein the electronic mechanical brake controller communicates with the wire-controlled chassis controller through a first private network and a second private network, and at the same time calculates and sends a corresponding wheel speed signal based on the signal of the wheel speed sensor. The electronic mechanical brake controller receives a request for braking force, drives the brake motor to drive the transmission mechanism, and promotes the actuation of the brake.

[0021] According to another specific implementation and preferred aspect of the present invention, the feel simulator includes a feel simulator torque sensor, a feel simulator controller, a feel simulator motor, a feel simulator transmission mechanism, and a feel simulator angle sensor, which are powered simultaneously by a first power supply and a second power supply, and communicate with other components through a first private network and a second private network; the feel simulator controller monitors the driver's input and obtains the driver's hand torque through the feel simulator torque sensor, calculates the corresponding feel simulation torque by receiving the associated signal of the steering actuator, and drives the feel simulator transmission mechanism to act on the steering wheel through the feel simulator motor, and outputs the steering wheel rotation angle signal through the feel simulator angle sensor.

[0022] In addition, the steering actuator is connected to the steering wheel, receives steering instructions, and ultimately realizes vehicle steering. The steering actuator includes a steering actuator controller, a steering actuator motor, a steering actuator transmission mechanism, and a steering actuator angle sensor, which are powered by a first power supply and a second power supply at the same time, and communicate with other components through a first private network and a second private network. In normal mode, the steering actuator receives the steering request transmitted by the wire-controlled chassis controller through the private network; when the wire-controlled chassis controller is in a fault state, it can respond to the steering wheel rotation angle request of the feel simulator.

[0023] In some specific embodiments, the drive-by-wire chassis controller further includes an active steering control module, wherein the active steering control module receives a yaw rate signal, a steering wheel angle signal, and a vehicle speed signal to form a steering actuator target angle request instruction. In other words, the present application can also perform active steering control to increase the accuracy and real-time performance of the drive-by-wire chassis system. Specifically, when the steering actuator is decoupled from the hand feel simulator, when the vehicle becomes unstable, the steering actuator can eliminate the vehicle instability by adjusting the appropriate displacement Δr, while the steering wheel angle δ does not change at this time. The conditional range of its action is: C2γ act ≤abs(γ tar -γ act )≤C1γ act , where C1 and C2 are the actual vehicle calibration coefficients, which are calibrated according to the actual state of the vehicle; the displacement Δr adjusted by the steering actuator is C(v ref ,δ)(γtar -γ act ), where C(v ref , δ) is a calibrated parameter and is a two-dimensional curve associated with vehicle speed and steering wheel angle. Another technical solution of the present invention is: a control method for a wire-controlled chassis, which adopts the above-mentioned wire-controlled chassis system, wherein the swing torque control module of the wire-controlled chassis controller receives the right front wheel speed signal, the right rear wheel speed signal, the left front wheel speed signal, and the left rear wheel speed signal, and calculates the vehicle reference speed v ref , the steering wheel angle input by the driver is δ, and the desired yaw rate γ tar It can be expressed as: Where l is the vehicle wheelbase, k(x) is a calibration parameter, and is a two-dimensional curve associated with vehicle speed and steering wheel angle. When the steering actuator is decoupled from the feel simulator, when the vehicle becomes unstable, the steering actuator can adjust the appropriate displacement Δr to eliminate the vehicle instability, while the steering wheel angle δ does not change. The range of its action conditions is: C2γ act ≤abs(γ tar -γ act )≤C1γ act , where C1 and C2 are the actual vehicle calibration coefficients, which are calibrated according to the actual state of the vehicle; the displacement Δr adjusted by the steering actuator is C(v ref ,δ)(γ tar -γ act ), where C(v ref , δ) is a calibrated parameter and is a two-dimensional curve associated with vehicle speed and steering wheel angle.

[0024] In view of the different contributions of various related modules in the existing drive-by-wire chassis system to the dynamic adjustment and safety of the entire vehicle, as well as the complexity and difficulty in implementing the corresponding integrated control algorithm, the above-mentioned drive-by-wire chassis system has designed an electronic and electrical architecture for the chassis domain, integrating drive-by-wire steering, drive-by-wire braking and drive-by-wire chassis controllers. In addition, in the architectural design of distributed actuators, in the event of system failure, the vehicle is controlled laterally to improve vehicle safety.

[0025] Due to the implementation of the above technical solution, the present invention has the following advantages compared with the prior art:

[0026] In view of the current situation in which the various related modules in the wire-controlled chassis system have different contributions to the dynamic adjustment and safety of the entire vehicle, the corresponding integrated control algorithms are complex and difficult to implement, and when the system partially or completely fails, it cannot meet the driver's input expectations. The present invention cleverly solves these shortcomings of the existing system through the overall design of the wire-controlled chassis system. With this system, the electromechanical brakes of the left front wheel controller and the right rear wheel controller are powered by a first power supply, while those of the right front wheel controller and the left rear wheel controller are powered by a second power supply. The by-wire chassis controller, the feel simulator, and the steering actuator are all redundantly powered by the first and second power supplies. The by-wire chassis controller receives signals from the first and second vehicle networks, the brake pedal sensor, and the yaw rate sensor, and then sends control commands to the electromechanical brake, the feel simulator, and the steering actuator via the first and second private networks, respectively. Furthermore, in the event of a complete or partial failure of the steering actuator, when the vehicle's steering wheel cannot promptly respond to steering commands issued by the driver via the steering wheel angle, the by-wire chassis controller can improve the vehicle's lateral dynamics. Therefore, the present invention not only enhances the performance coupling of chassis by-wire steering and by-wire braking to increase the accuracy and real-time nature of lateral control, but also improves the control robustness of the vehicle's response. Furthermore, in the event of a complete or partial failure of the steering actuator, the vehicle's yaw angle can still meet the driver's expected input. Furthermore, the use of redundant power supplies reduces the system's failure rate and the cost of redundant design. DETAILED DESCRIPTION

[0027] Figure 1 is a schematic diagram of a wire-controlled chassis system of the present invention;

[0028] Figure 2 for Figure 1 Schematic diagram of the center-by-wire chassis controller;

[0029] Figure 3 is a schematic diagram of an electromechanical brake for any wheel of the present invention;

[0030] Figure 4 is a schematic diagram of a hand feel simulator system of the present invention;

[0031] Figure 5 is a schematic diagram of a steering actuator system of the present invention;

[0032] Figure 6 Schematic diagram of the yaw moment control module of the present invention;

[0033] Figure 7 This is a schematic diagram of active steering control according to the present invention;

[0034] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, a detailed description is provided below in conjunction with specific embodiments. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar modifications without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0035] like Figures 1 to 7 As shown, the wire-controlled chassis system involved in this embodiment includes a wire-controlled chassis controller, a brake pedal sensor, a yaw angular velocity sensor, a left front wheel controller (including a left front electronic mechanical brake and a left front wheel speed sensor), a left rear wheel controller (including a left rear electronic mechanical brake and a left rear wheel speed sensor), a right front wheel controller (including a right front electronic mechanical brake and a right front wheel speed sensor), a right rear wheel controller (including a right rear electronic mechanical brake and a right rear wheel speed sensor), a first power supply, a second power supply, a hand feeling simulator, a steering actuator, a first vehicle network and a second vehicle network, wherein the wire-controlled chassis controller, the hand feeling simulator and the steering actuator are redundantly connected by the first and second power supplies. The left front electronic mechanical brake and the right rear electronic mechanical brake are powered by the first power supply, and the right front electronic mechanical brake and the left rear electronic mechanical brake are powered by the second power supply; the right front wheel speed sensor is powered by the right front electronic mechanical brake and transmits signals, the right rear wheel speed sensor is powered by the right rear electronic mechanical brake and transmits signals, the left front wheel speed sensor is powered by the left front electronic mechanical brake and transmits signals, the left rear wheel speed sensor is powered by the left rear electronic mechanical brake and transmits signals; the wire-controlled chassis controller communicates with other vehicle components through the first vehicle network and the second vehicle network; a communication channel is maintained between the feel simulator and the steering actuator.

[0036] In some specific embodiments, the function of the wire-controlled chassis controller is to receive signals from the first vehicle network, the second vehicle network, the brake pedal sensor, and the yaw rate sensor, and communicate with the independent electronic mechanical brakes of the four wheels through the first private network and the second private network. Figure 2 As shown, the chassis controller performs logical calculations and control instructions, sending these instructions to the electromechanical brake, feel simulator, and steering actuator via the first and second private networks, respectively. To reduce the failure rate of the by-wire chassis controller, redundant first and second power supplies are used to power the controller, and redundant MCUs 1 and 2 are provided for logic processing.

[0037] In some specific embodiments, the left front electromechanical brake, the left rear electromechanical brake, the right front electromechanical brake, and the right rear electromechanical brake have the same structure, that is, Figure 3As shown, each electronic mechanical brake includes an electronic mechanical brake controller, a brake motor, a transmission mechanism and a brake; wherein the electronic mechanical brake controller communicates with the wire-controlled chassis controller through the first private network and the second private network, and at the same time calculates and sends the corresponding wheel speed signal based on the signal of the wheel speed sensor. The electronic mechanical brake controller receives the request for braking force, drives the brake motor to drive the transmission mechanism, and promotes the actuation of the brake.

[0038] In some embodiments, the hand feel simulator is connected to the steering wheel, converting the driver's steering request into an electrical signal and providing the driver with steering feedback. Figure 4 As shown, the feel simulator includes a feel simulator torque sensor, a feel simulator controller, a feel simulator motor, a feel simulator transmission mechanism, and a feel simulator angle sensor, which are powered by a first power supply and a second power supply at the same time, and communicate with other components through a first private network and a second private network; the feel simulator controller monitors the driver's input and obtains the driver's hand torque through the feel simulator torque sensor, calculates the corresponding feel simulation torque by receiving the associated signal of the steering actuator, and drives the feel simulator transmission mechanism to act on the steering wheel through the feel simulator motor, and outputs the steering wheel rotation angle signal through the feel simulator angle sensor.

[0039] In some specific embodiments, the steering actuator is connected to the steering wheel, receives the steering instruction, and finally realizes the vehicle steering; Figure 5 As shown, the steering actuator includes a steering actuator controller, a steering actuator motor, a steering actuator transmission mechanism, and a steering actuator angle sensor. Also, to ensure the safety of the system, it is powered by a first power supply and a second power supply at the same time, and communicates with other components through a first private network and a second private network. In normal mode, the steering actuator receives a steering request transmitted by the wire-controlled chassis controller through the private network. When the wire-controlled chassis controller is in a fault state, it can respond to the steering wheel rotation angle request of the feel simulator.

[0040] Based on the above-mentioned wire-controlled chassis system, in the event of complete or partial failure of the steering actuator, when the vehicle's steering wheel cannot promptly respond to the steering command issued by the driver through the steering wheel angle, the yaw moment control module in the wire-controlled chassis controller actively intervenes to improve the vehicle's lateral dynamics; combined with Figure 6 As shown, the yaw moment control module receives the yaw rate signal, the steering wheel angle signal, the steering actuator status signal, the right front wheel speed signal, the right rear wheel speed signal, the left front wheel speed signal, and the left rear wheel speed signal, and outputs the right front electronic mechanical braking torque request, the left front electronic mechanical braking torque request, the right rear electronic mechanical braking torque request, the left rear electronic mechanical braking torque request, and the driving torque request through calculation.

[0041] In some specific embodiments, the yaw moment control module receives the right front wheel speed signal, the right rear wheel speed signal, the left front wheel speed signal, and the left rear wheel speed signal, and calculates the reference vehicle speed v ref , the steering wheel angle input by the driver is δ, and the desired yaw rate γ tar It can be expressed as:

[0042]

[0043] Where l is the vehicle wheelbase, k(x) is a calibration parameter, which is a two-dimensional curve associated with vehicle speed and steering wheel angle.

[0044] The actual yaw rate signal γ act The yaw rate deviation γ is measured by the yaw rate sensor. err Equal to γ tar -γ act , the control target is 0; according to the front wheel distance T f and rear track T r , the obtained yaw correction torque dMz and the left front wheel braking force F fl , right front wheel braking force F fr , left rear wheel braking force F rl , the distribution of the right rear wheel braking force Frr is as follows:

[0045]

[0046] For the purpose of vehicle control, F fl 、F fr 、F rl 、F rr Braking force and γ err The real-time relationship can adopt but is not limited to PID control strategy. The ultimate goal is to ensure that the vehicle's yaw angle can meet the driver's input expectations when the steering actuator fails. ref When the speed is lower than the threshold v0, the yaw moment control module sends a drive torque request to keep the vehicle speed at v0 to facilitate the control of the vehicle yaw angle.

[0047] Combine Figure 7 As shown in Figure 1, the active steering control module in the drive-by-wire chassis controller receives the yaw rate signal, steering wheel angle signal, and vehicle speed signal to generate a target angle request command for the steering actuator. Specifically, due to the decoupling of the steering actuator from the feel simulator, when the vehicle becomes unstable, the steering actuator can adjust the appropriate displacement Δr to eliminate the vehicle instability, while the steering wheel angle δ does not change. The operating condition range is: C2γ act ≤abs(γ tar -γact )≤C1γ act Among them, C1 and C2 are the actual vehicle calibration coefficients, which are calibrated according to the actual state of the vehicle; in the above position, the displacement of the steering actuator adjusted by Δr = C(v ref ,δ)(γ tar -γ act ), where C(v ref , δ) is a calibrated parameter, which is a two-dimensional curve associated with vehicle speed and steering wheel angle.

[0048] In summary, under the system and corresponding control, the electronic mechanical brakes of the left front wheel controller and the right rear wheel controller are powered by the first power supply, the electronic mechanical brakes of the right front wheel controller and the left rear wheel controller are powered by the second power supply, the wire-controlled chassis controller, the feel simulator and the steering actuator are all redundantly powered by the first and second power supplies, and the wire-controlled chassis controller receives signals from the first vehicle network, the second vehicle network, the brake pedal sensor and the yaw angular velocity sensor, and then sends control instructions to the electronic mechanical brake, the feel simulator and the steering actuator respectively through the first private network and the second private network, and in the case of complete or partial failure of the steering actuator, when the vehicle steering wheel cannot respond in time to the steering instruction issued by the driver through the steering wheel angle, the wire-controlled chassis controller can improve the lateral dynamics of the vehicle. Therefore, one aspect of the present invention It can not only enhance the performance coupling of chassis wire-controlled steering and wire-controlled braking to increase the accuracy and real-time performance of lateral control; it can also improve the control robustness of the vehicle's response; on the other hand, in the event of complete or partial failure of the steering actuator, the vehicle's yaw angle can meet the driver's input expectations. In addition, under the cross-power connection of the four independent electronic mechanical brakes, if any power supply fails, the wire-controlled chassis controller can provide at least 50% of the power output, which is highly practical. At the same time, redundant power supply is used to reduce the failure rate of the system and the cost of redundant design. Thirdly, the electronic and electrical architecture of the chassis domain is designed, integrating wire-controlled steering, wire-controlled braking and wire-controlled chassis controller, and in the architectural design of distributed actuators, in the event of system failure, the vehicle is controlled laterally to improve vehicle safety.

[0049] The above detailed description of the present invention is intended to enable persons familiar with the art to understand the contents of the present invention and implement them. It does not limit the scope of protection of the present invention. Any equivalent changes or modifications made based on the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A drive-by-wire chassis system comprising a drive-by-wire chassis controller, wheel controllers, a feel simulator, a steering actuator, a brake pedal sensor, and a yaw rate sensor. Each wheel controller includes an electromechanical brake and a wheel speed sensor, and the corresponding controllers are a left front wheel controller, a left rear wheel controller, a right front wheel controller, and a right rear wheel controller. The feel simulator is connected to the steering wheel and converts the driver's steering request into a signal. The system is characterized by: The electronic mechanical brakes of the left front wheel controller and the right rear wheel controller are powered by a first power supply; the electronic mechanical brakes of the right front wheel controller and the left rear wheel controller are powered by a second power supply; the wire-controlled chassis controller, the feel simulator and the steering actuator are all redundantly powered by the first and second power supplies. The wire-controlled chassis controller receives signals from the first vehicle network, the second vehicle network, the brake pedal sensor and the yaw angular velocity sensor, and communicates with each electronic mechanical brake through the first private network and the second private network to send control instructions to each electronic mechanical brake, the feel simulator and the steering actuator respectively. A communication channel is maintained between the feel simulator and the steering actuator. When the steering actuator fails completely or partially, the wire-controlled chassis controller can also change the vehicle's yaw angle to match the steering request of the steering wheel target angle based on the yaw correction torque and the braking force of each wheel calculated according to the vehicle's state parameters.

2. The wire-controlled chassis system according to claim 1, characterized in that: The wire-controlled chassis controller communicates with other vehicle components via the first vehicle network and the second vehicle network; and / or the wire-controlled chassis controller uses redundant MCU1 and MCU2 for logic processing.

3. The wire-controlled chassis system according to claim 1, characterized in that: The drive-by-wire chassis controller includes a yaw moment control module, which receives a yaw angular velocity signal, a steering wheel angle signal, a steering actuator status signal, a right front wheel speed signal, a right rear wheel speed signal, a left front wheel speed signal, and a left rear wheel speed signal, and calculates and outputs a right front electronic mechanical braking torque request, a left front electronic mechanical braking torque request, a right rear electronic mechanical braking torque request, a left rear electronic mechanical braking torque request, and a drive torque request.

4. The wire-controlled chassis system according to claim 3, characterized in that: The yaw moment control module receives the right front wheel speed signal, the right rear wheel speed signal, the left front wheel speed signal, and the left rear wheel speed signal, and calculates the vehicle's reference speed v ref , the steering wheel angle input by the driver is δ, and the desired yaw rate γ tar Expressed as: Where l is the vehicle wheelbase, k(x) is a calibration parameter, and is a two-dimensional curve associated with vehicle speed and steering wheel angle; and / or, the actual yaw rate signal γ act The yaw rate deviation γ is measured by the yaw rate sensor. err Equal to γ tar -γ act , the control target is 0.

5. The wire-controlled chassis system according to claim 4, characterized in that: According to the front wheelbase T f and rear track T r , the obtained yaw correction torque dMz and the left front wheel braking force F fl , right front wheel braking force F fr , left rear wheel braking force F rl , the distribution of the right rear wheel braking force Frr is as follows: Among them F fl 、F fr 、F rl 、F rr Braking force and γ err In the event of a steering actuator failure, the vehicle's yaw angle can meet the steering target angle request input by the driver; and / or when the reference vehicle speed v ref When the speed is lower than the threshold v0, the yaw moment control module sends a drive torque request to keep the vehicle speed at v0 to facilitate the control of the vehicle yaw angle.

6. The wire-controlled chassis system according to claim 1, characterized in that: The electronic mechanical brake includes an electronic mechanical brake controller, a brake motor, a transmission mechanism and a brake, wherein the electronic mechanical brake controller communicates with the wire-controlled chassis controller through a first private network and a second private network, and at the same time calculates and sends a corresponding wheel speed signal based on the signal of the wheel speed sensor. The electronic mechanical brake controller receives a request for braking force, drives the brake motor to drive the transmission mechanism, and promotes the actuation of the brake.

7. The wire-controlled chassis system according to claim 1, characterized in that: The hand feel simulator includes a hand feel simulator torque sensor, a hand feel simulator controller, a hand feel simulator motor, a hand feel simulator transmission mechanism, and a hand feel simulator angle sensor, which are powered simultaneously by a first power supply and a second power supply, and communicate with other components through a first private network and a second private network; the hand feel simulator controller monitors the driver's input and obtains the driver's hand torque through the hand feel simulator torque sensor, calculates the corresponding hand feel simulation torque by receiving the related signal of the steering actuator, and drives the hand feel simulator transmission mechanism to act on the steering wheel through the hand feel simulator motor, and outputs the steering wheel rotation angle signal through the hand feel simulator angle sensor.

8. The wire-controlled chassis system according to claim 1, characterized in that: The steering actuator is connected to the steering wheel, receives steering commands, and ultimately realizes vehicle steering. The steering actuator includes a steering actuator controller, a steering actuator motor, a steering actuator transmission mechanism, and a steering actuator angle sensor. The steering actuator is powered by a first power supply and a second power supply simultaneously, and communicates with other components via a first private network and a second private network. In normal mode, the steering actuator receives steering requests transmitted by the wire-controlled chassis controller via the private network. When the drive-by-wire chassis controller fails, it can respond to the steering wheel rotation angle request of the feel simulator.

9. The wire-controlled chassis system according to claim 1, characterized in that: The drive-by-wire chassis controller also includes an active steering control module, which receives a yaw rate signal, a steering wheel angle signal, and a vehicle speed signal to form a steering actuator target angle request instruction.

10. A control method for a wire-controlled chassis, characterized in that: The method adopts the wire-controlled chassis system according to any one of claims 1 to 9, wherein the pendulum torque control module of the wire-controlled chassis controller receives the right front wheel speed signal, the right rear wheel speed signal, the left front wheel speed signal, and the left rear wheel speed signal, and calculates the reference speed v of the vehicle. ref , the steering wheel angle input by the driver is δ, and the desired yaw rate γ tar Expressed as: Where l is the vehicle wheelbase, k(x) is a calibration parameter, and is a two-dimensional curve associated with vehicle speed and steering wheel angle. At the same time, when the steering actuator is decoupled from the feel simulator, when the vehicle becomes unstable, the steering actuator adjusts the appropriate displacement Δr to eliminate the vehicle instability, while the steering wheel angle δ does not change at this time. The range of its action conditions is: C2γ act ≤abs(γ tar -γ act 》≤C1γ act , where C1 and C2 are the actual vehicle calibration coefficients, which are calibrated according to the actual state of the vehicle; the displacement Δr adjusted by the steering actuator is C(v ref ,δ)(γ tar -γ act ), where C(v ref , δ) is a calibrated parameter and is a two-dimensional curve associated with vehicle speed and steering wheel angle.

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