Intelligent electric chassis configuration and fault-tolerant control method of intelligent electric chassis

Abstract

The application discloses an intelligent electric chassis configuration and a fault-tolerant control method of the intelligent electric chassis, and relates to the technical field of electric chassis. The chassis configuration comprises a front axle centralized motor drive assembly, a rear axle distributed motor drive assembly, a front axle electronic hydraulic brake system, a rear axle electronic mechanical brake system and a chassis domain controller. The front axle centralized motor drive assembly comprises a centralized drive motor, a front wheel speed reducer and a drive half shaft which are sequentially connected. The rear axle distributed motor drive assembly comprises a left rear wheel end drive motor and a left rear wheel speed reducer which are sequentially connected, and a right rear wheel end drive motor and a right rear wheel speed reducer which are sequentially connected. The front axle electronic hydraulic brake system comprises a first main brake unit and a redundant brake unit. The rear axle electronic mechanical brake system comprises a second main brake unit. The chassis domain controller is used for controlling the centralized drive motor, the left and right rear wheel end drive motors, the first main brake unit, the redundant brake unit, the second main brake unit, a front axle steer-by-wire system, an intelligent suspension system and an intelligent tire. The application can improve the chassis safety and fault-tolerant capability to support high-level automatic driving functions.

Description

Technical Field

[0001] This invention relates to the field of electric chassis technology, and in particular to an intelligent electric chassis configuration and a fault-tolerant control method for an intelligent electric chassis. Background Technology

[0002] The electric chassis configuration mainly includes subsystems such as drive, braking, steering, and suspension, and their performance level directly determines the overall performance of the chassis. With the increasing diversity of intelligent vehicle applications, new demands are being placed on the dynamic control and safety performance indicators of the chassis configuration. Current research on electric chassis configurations and fault-tolerant control methods based on chassis domain control technology is insufficient, resulting in low chassis safety and fault tolerance, making it unable to support high-level autonomous driving functions. Therefore, there is a need for an intelligent electric chassis configuration that can improve safety and fault tolerance. Summary of the Invention

[0003] The purpose of this invention is to provide an intelligent electric chassis configuration and a fault-tolerant control method for the intelligent electric chassis, which can improve chassis safety and fault tolerance to support high-level autonomous driving functions.

[0004] To achieve the above objectives, the present invention provides the following solution:

[0005] A smart electric chassis configuration includes:

[0006] The chassis domain controller and the front axle centralized motor drive assembly, the rear axle distributed motor drive assembly, the front axle electro-hydraulic braking system, the rear axle electro-mechanical braking system, the front axle central steering system, the intelligent suspension system, the left front wheel intelligent tire, the right front wheel intelligent tire, the left rear wheel intelligent tire, and the right rear wheel intelligent tire, all connected to the chassis domain controller respectively.

[0007] The front axle centralized motor drive assembly includes: a centralized drive motor, a front wheel reducer, and a drive half-shaft connected in sequence; the centralized drive motor is connected to the chassis domain controller, and the drive half-shaft is connected to the left front wheel smart tire and the right front wheel smart tire; the rear axle distributed motor drive assembly includes: a left rear wheel end drive motor and a left rear wheel reducer connected in sequence, and a right rear wheel end drive motor and a right rear wheel reducer connected in sequence; both the left and right rear wheel end drive motors are connected to the chassis domain controller; the left rear wheel reducer is connected to the left rear wheel smart tire, and the right rear wheel reducer is connected to the right rear wheel smart tire;

[0008] The front axle electro-hydraulic braking system includes a first main braking unit and a redundant braking unit; the rear axle electro-mechanical braking system includes a second main braking unit; the first main braking unit, the redundant braking unit, and the second main braking unit are all connected to the chassis domain controller.

[0009] The chassis domain controller is used to control the centralized drive motor, the left rear wheel drive motor, the right rear wheel drive motor, the first main braking unit, the redundant braking unit, the second main braking unit, the front axle-controlled steering system, the intelligent suspension system, the left front wheel intelligent tire, the right front wheel intelligent tire, the left rear wheel intelligent tire, and the right rear wheel intelligent tire.

[0010] Optionally, the front axle centralized motor drive assembly further includes a centralized drive motor controller, wherein the centralized drive motor is connected to the chassis domain controller via the centralized drive motor controller.

[0011] Optionally, the rear axle distributed motor drive assembly further includes: a left rear wheel end drive motor controller and a right rear wheel end drive motor controller; the left rear wheel end drive motor is connected to the chassis domain controller through the left rear wheel end drive motor controller; the right rear wheel end drive motor is connected to the chassis domain controller through the right rear wheel end drive motor controller.

[0012] Optionally, the front axle-controlled steering system includes two steering modules, each of which includes a steering control unit, a steering motor driver, and a steering motor connected in sequence, and the steering control unit is connected to the chassis domain controller.

[0013] Optionally, the left front wheel smart tire, the right front wheel smart tire, the left rear wheel smart tire, and the right rear wheel smart tire all include a tire body and an accelerometer, a strain gauge, a pressure sensor, and a signal transmission and processing module disposed within the tire body.

[0014] A fault-tolerant control method for an intelligent electric chassis, applied to the aforementioned intelligent electric chassis configuration, the method comprising:

[0015] When the central drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor are all working normally, the chassis domain controller controls the central drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor according to the pedal command;

[0016] When the left rear wheel drive motor or the right rear wheel drive motor fails, the chassis domain controller controls the normal motor and the front axle steering system based on the deviation between the current driving state and the desired driving state of the chassis. When the left rear wheel drive motor fails, the normal motor is the right rear wheel drive motor and the centralized drive motor. When the right rear wheel drive motor fails, the normal motor is the left rear wheel drive motor and the centralized drive motor.

[0017] When the centralized drive motor fails, the chassis domain controller controls the left rear wheel drive motor and the right rear wheel drive motor according to the pedal command;

[0018] When both the first and second main braking units are working normally, the chassis domain controller controls the front axle electro-hydraulic braking system and the rear axle electromechanical braking system according to the pedal command;

[0019] Without anti-lock braking, when the first main braking unit fails, the chassis domain controller controls the redundant braking unit of the front axle electro-hydraulic braking system to operate; when the second main braking unit fails, the chassis domain controller controls the normally functioning smart tires among the left front wheel smart tire, right front wheel smart tire, left rear wheel smart tire, and right rear wheel smart tire, as well as the front axle-controlled steering system, according to pedal commands; when multiple failures occur in the first main braking unit, second main braking unit, and redundant braking unit, failing to meet the chassis braking deceleration requirements, the chassis domain controller controls the normally functioning parts of the first main braking unit, second main braking unit, and redundant braking unit, as well as the regenerative braking system.

[0020] In anti-lock braking mode, when the anti-lock braking of the left front wheel smart tire or the right front wheel smart tire fails, the chassis domain controller adjusts the brake master cylinder pressure in the redundant braking unit.

[0021] Optionally, when the centralized drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor are all operating normally, the chassis domain controller controls the centralized drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor according to the pedal command, specifically including:

[0022] When the centralized drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor are all working normally, the chassis domain controller calculates the torque of the centralized drive motor, the torque of the left rear wheel end drive motor, and the torque of the right rear wheel end drive motor according to the pedal command.

[0023] The centralized drive motor is controlled according to its torque;

[0024] The left rear wheel drive motor is controlled according to the torque of the left rear wheel drive motor.

[0025] The right rear wheel drive motor is controlled according to the torque of the right rear wheel drive motor.

[0026] Optionally, when the left rear wheel drive motor or the right rear wheel drive motor fails, the chassis domain controller controls the normal motor and the front axle remote steering system based on the deviation between the current driving state and the desired driving state of the chassis, specifically including:

[0027] When the left rear wheel drive motor or the right rear wheel drive motor fails, the chassis domain controller corrects the torque of the normal motor based on the deviation between the current driving state and the desired driving state of the chassis.

[0028] Determine whether the current driving state has reached the desired driving state;

[0029] If the desired driving state is not achieved, the steering angle of the front axle-controlled steering system is corrected based on the deviation between the current driving state and the desired driving state.

[0030] If the condition is met, the correction process ends.

[0031] Optionally, when both the first and second main braking units are operating normally, the chassis domain controller controls the front axle electro-hydraulic braking system and the rear axle electromechanical braking system according to pedal commands, specifically including:

[0032] When both the first and second main braking units are working normally, the chassis domain controller receives mechanical braking force according to the pedal command.

[0033] The front axle electro-hydraulic braking system and the rear axle electro-mechanical braking system are controlled according to the mechanical braking force.

[0034] Optionally, in the absence of anti-lock braking, when the second main braking unit fails, the chassis domain controller controls the normally functioning smart tires among the left front wheel smart tire, right front wheel smart tire, left rear wheel smart tire, and right rear wheel smart tire, as well as the front axle-controlled steering system, based on pedal commands. Specifically, this includes:

[0035] Without anti-lock braking, when the second main braking unit fails, the chassis domain controller obtains mechanical braking force based on pedal commands;

[0036] The mechanical braking force is used to correct the working smart tire among the left front wheel smart tire, right front wheel smart tire, left rear wheel smart tire and right rear wheel smart tire;

[0037] Determine if there is a deviation between the current yaw rate of the chassis and the expected yaw rate;

[0038] If a deviation exists, the front axle steering system is controlled based on the deviation between the current yaw rate and the desired yaw rate.

[0039] If no deviation is found, the correction process ends.

[0040] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0041] This invention employs a chassis domain controller to control a centralized drive motor, a left rear wheel drive motor, a right rear wheel drive motor, a first main braking unit, a redundant braking unit, a second main braking unit, a front axle-controlled steering system, an intelligent suspension system, and intelligent tires for the left front wheel, right front wheel, left rear wheel, and right rear wheel. This allows the entire upper-level control logic of the chassis to be implemented by the chassis domain controller, while the lower-level subsystems are only responsible for executing instructions. This improves chassis safety and fault tolerance to support advanced autonomous driving functions. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of the intelligent electric chassis configuration of the present invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0046] like Figure 1 As shown, an embodiment of the present invention provides an intelligent electric chassis configuration, characterized in that it includes:

[0047] The chassis domain controller, along with the front axle centralized motor drive assembly, the rear axle distributed motor drive assembly, the front axle electro-hydraulic braking system, the rear axle electro-mechanical braking system, the front axle axial steering system, the intelligent suspension system, and the left front wheel intelligent tire, right front wheel intelligent tire, left rear wheel intelligent tire, and right rear wheel intelligent tire, all connected to the chassis domain controller. The front axle centralized motor drive assembly is connected to the electro-hydraulic braking system, the front axle axial steering system, the front axle intelligent suspension system, and the front axle intelligent tires (left front wheel intelligent tire and right front wheel intelligent tire). The front axle mechanism, consisting of tires, provides driving force, braking force, and vertical force to the front half of the chassis, and enables steering under normal operating conditions. The rear axle distributed motor drive assembly, along with the rear axle electromechanical braking system, rear axle intelligent suspension system, and rear axle intelligent tires (left and right rear intelligent tires), forms the rear axle mechanism, providing driving force, braking force, and vertical force to the rear half of the chassis. The front axle centralized motor drive assembly includes a centralized drive motor, a front wheel reducer, and a drive... (The sentence is incomplete and requires further context to translate accurately.) The system includes a drive half-shaft; a centralized drive motor connected to the chassis domain controller, and the drive half-shaft connected to the left front wheel smart tire and the right front wheel smart tire; a rear axle distributed motor drive assembly including: a left rear wheel end drive motor and a left rear wheel reducer connected in sequence, and a right rear wheel end drive motor and a right rear wheel reducer connected in sequence; both the left and right rear wheel end drive motors are connected to the chassis domain controller; the left rear wheel reducer is connected to the left rear wheel smart tire, and the right rear wheel reducer is connected to the right rear wheel smart tire; the front axle electro-hydraulic braking system includes a first main braking unit and a redundant braking unit; the rear axle electro-mechanical braking system includes a second main braking unit; both the first and second main braking units are connected to the chassis domain controller; the chassis domain controller is used to control the centralized drive motor, the left rear wheel end drive motor, the right rear wheel end drive motor, the first main braking unit, the redundant braking unit, the second main braking unit, the front axle-controlled steering system, the intelligent suspension system, the left front wheel smart tire, the right front wheel smart tire, the left rear wheel smart tire, and the right rear wheel smart tire respectively.

[0048] In practical applications, the redundant braking unit includes the power supply, pump motor, hydraulic brake valve, control unit, wheel speed acquisition device, and communication network of the front axle electro-hydraulic braking system. The power supply provides power to the pump motor, hydraulic brake valve, control unit, and wheel speed acquisition device. According to the hydraulic oil flow direction, the connections are: pump motor (master cylinder), hydraulic brake valve, and wheel cylinders. The control unit regulates the start / stop of the pump motor and the opening of the brake valve. The wheel speed acquisition device provides wheel speed information to the chassis domain controller via the communication network. The structure of the redundant braking unit is the existing structure and will not be described in detail here. The redundant braking unit is arranged in parallel with the two master braking units. When the master braking units are working normally, the redundant braking unit is not in operation; when the master braking units fail, the redundant braking unit is activated.

[0049] In practical applications, the front axle centralized motor drive assembly also includes a centralized drive motor controller, through which the centralized drive motor is connected to the chassis domain controller.

[0050] In practical applications, the rear axle distributed motor drive assembly also includes: a left rear wheel end drive motor controller and a right rear wheel end drive motor controller; the left rear wheel end drive motor is connected to the chassis domain controller through the left rear wheel end drive motor controller; the right rear wheel end drive motor is connected to the chassis domain controller through the right rear wheel end drive motor controller.

[0051] In practical applications, the front axle-controlled steering system includes two steering modules. Each module comprises a steering control unit, a steering motor driver, and a steering motor connected in sequence. The steering control unit is connected to the chassis domain controller, employing a dual steering motor and driver configuration to form two independent steering control channels. When one motor fails, the other, functioning motor, enables steering. When the entire front axle-controlled steering system fails, the chassis domain controller corrects the driving and braking forces of the four wheels through the drive motor and brake-by-wire system, generating the desired yaw moment. This controls the chassis's yaw rate and lateral position deviation, achieving differential steering. This process is existing technology, namely vehicle differential steering technology.

[0052] In practical applications, other redundant hardware in the front axle-controlled steering system includes a power supply, torque angle sensor, and communication network. The two steering control units and the chassis domain controller communicate via the network. The steering control unit sends the target control value to the steering motor driver, causing the steering motor to generate actual torque to control the downstream mechanical structure and achieve vehicle steering. Simultaneously, the torque angle sensor collects the torque angle signal.

[0053] In practical applications, when the intelligent suspension system fails, the chassis domain controller observes the output gain of the faulty actuator (integrated within the intelligent suspension to achieve active control of the suspension's vertical force) based on the observer (integrated within the chassis domain controller). It then calculates the suspension dynamic deflection deviation to obtain the actual value of the failed suspension's active control force. Subsequently, fault-tolerant control algorithms, such as PID and sliding mode control, are used to correct the suspension's active control force. Under suspension safety constraints, the vertical displacement and velocity of the suspension are maintained within a reasonable range, thus compensating for the failed suspension's vibration reduction and attitude control functions. Calculating the suspension dynamic deflection deviation is crucial for locating the position of the faulty suspension (left front / right front / left rear / right rear) and then collecting the actual value of the suspension's control force for subsequent fault-tolerant compensation.

[0054] In practical applications, the left front wheel smart tire, right front wheel smart tire, left rear wheel smart tire, and right rear wheel smart tire all include a tire body and accelerometers, strain gauges, pressure sensors, and signal transmission and processing modules installed within the tire body. The smart tire can accurately sense tire pressure, temperature, wear, force, speed parameters, as well as road contact conditions and adhesion coefficients, and provide the sensed signals to the chassis domain controller. The chassis domain controller can judge the health of the tire based on the tire pressure, temperature, and wear conditions collected by the smart tire, and warn of the danger of tire inflation, tire replacement, or even tire blowout. It can also feed back the tire force status, such as lateral and longitudinal forces and self-aligning torque, to the dynamic control module of the chassis domain controller to improve the control accuracy of drive, braking, and steering. It can centrally process acceleration signals and wheel speed parameters to improve the accuracy of vehicle speed estimation. It can also optimize drive, braking, anti-skid control, and vehicle handling stability control performance by referring to the road adhesion conditions of each wheel.

[0055] This invention comprises a front axle centralized motor drive assembly and a rear axle distributed motor drive assembly forming a chassis drive-by-wire system. Its function is to provide the total driving force required by the chassis during driving and the regenerative braking force required during braking. A front axle electro-hydraulic braking system and a rear axle electromechanical braking system form a brake-by-wire system, which provides the mechanical braking force required by the chassis. A chassis domain controller, which can be located on either the front or rear axle, monitors the operating status of each chassis subsystem in real time and integrates control of the front and rear axle mechanisms according to driver commands. This enables the intelligent electric chassis to perform functions such as driving, braking, steering, vibration damping, and attitude control, including normal operating condition control and fault-tolerant control. The upper-level control logic of the entire chassis is implemented by the chassis domain controller, while the lower-level subsystems are only responsible for executing commands. This ensures the tracking accuracy of the target driving trajectory, improves the safety, handling stability, comfort, and fault tolerance of the electric chassis, and supports high-level autonomous driving functions.

[0056] This invention also provides a fault-tolerant control method for an intelligent electric chassis, applied to the aforementioned intelligent electric chassis configuration, the method comprising:

[0057] When the central drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor are all working normally, the chassis domain controller controls the central drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor according to the pedal command.

[0058] When the left rear wheel drive motor or the right rear wheel drive motor fails, the chassis domain controller controls the normal motor and the front axle steering system based on the deviation between the current driving state and the desired driving state of the chassis. When the left rear wheel drive motor fails, the normal motor is the right rear wheel drive motor and the centralized drive motor. When the right rear wheel drive motor fails, the normal motor is the left rear wheel drive motor and the centralized drive motor.

[0059] When the centralized drive motor fails, the chassis domain controller controls the left rear wheel drive motor and the right rear wheel drive motor according to the pedal command.

[0060] When both the first and second main braking units are working normally, the chassis domain controller controls the front axle electro-hydraulic braking system and the rear axle electromechanical braking system according to the pedal commands.

[0061] Without anti-lock braking, when the first main braking unit fails, the chassis domain controller controls the redundant braking unit of the front axle electro-hydraulic braking system to operate, switching to the redundant braking unit of the front axle electro-hydraulic braking system. When the second main braking unit fails, the chassis domain controller controls the normally functioning smart tires among the left front wheel, right front wheel, left rear wheel, and right rear wheel smart tires, as well as the front axle-controlled steering system, according to pedal commands. When multiple failures occur in the first main braking unit, second main braking unit, and redundant braking unit, failing to meet the chassis braking deceleration requirements, the chassis domain controller controls the normally functioning parts of the first main braking unit, second main braking unit, and redundant braking unit—that is, the front axle electro-hydraulic braking system, rear axle electro-mechanical braking system, and regenerative braking system—to fully utilize the electro-braking efficiency.

[0062] In anti-lock braking mode, when the anti-lock braking of the left front wheel smart tire or the right front wheel smart tire fails, the chassis domain controller adjusts the brake master cylinder pressure in the redundant braking unit.

[0063] As an optional implementation, when the centralized drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor are all operating normally, the chassis domain controller controls the centralized drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor according to the pedal command, specifically including:

[0064] When the central drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor are all working normally, the chassis domain controller calculates the torque of the central drive motor, the torque of the left rear wheel end drive motor, and the torque of the right rear wheel end drive motor based on the pedal command. This calculation process is existing and can be generally simplified as the motor torque being proportional to the pedal command.

[0065] The centralized drive motor is controlled based on its torque.

[0066] The left rear wheel drive motor is controlled based on the torque of the left rear wheel drive motor.

[0067] The right rear wheel drive motor is controlled based on the torque of the right rear wheel drive motor.

[0068] As an optional implementation, when the left rear wheel drive motor or the right rear wheel drive motor fails, the chassis domain controller controls the normal motor and the front axle remote steering system based on the deviation between the current driving state and the desired driving state of the chassis. Specifically, this includes:

[0069] When the left rear wheel drive motor or the right rear wheel drive motor fails, the chassis domain controller corrects the torque of the normal motor based on the deviation between the current driving state and the desired driving state of the chassis.

[0070] Determine whether the current driving state has reached the desired driving state.

[0071] If the desired driving state is not achieved, the steering angle of the front axle steering system is adjusted based on the deviation between the current driving state and the desired driving state.

[0072] If the condition is met, the correction process ends.

[0073] When either the left or right rear wheel drive motor fails, the chassis domain controller adjusts the torque of the normal motors and the front axle steering system based on the deviation between the current and desired driving states. More specifically, when the left rear wheel drive motor fails, the controller adjusts the torque of the right rear wheel and the centralized drive motor based on the deviation between the current and desired driving states, including speed and yaw rate deviations (using algorithms such as PID or sliding mode control). For example, using a PID method, the input is the vehicle speed and yaw rate deviation under single motor failure, and the output is the adjusted torque of the normal motor. If redistributing the driving force of the normal motor still fails to achieve the desired driving state, the steering angle of the front axle steering system is further adjusted based on the state deviation. The same applies when the right rear wheel drive motor fails.

[0074] As an optional implementation, when the centralized drive motor fails, the chassis domain controller controls the left and right rear wheel drive motors according to the pedal command. Specifically, when the centralized drive motor fails, the chassis domain controller treats the four-wheel drive chassis as a rear-wheel drive chassis. The total drive motor torque calculated according to the pedal command is received and output by the rear axle distributed motor drive assembly (left and right rear wheel drive motors), and the front axle remote steering system does not intervene.

[0075] As an optional implementation, when both the first and second main braking units are operating normally, the chassis domain controller controls the front axle electro-hydraulic braking system and the rear axle electromechanical braking system according to pedal commands, specifically including:

[0076] When both the first and second main braking units are working normally, the chassis domain controller obtains the mechanical braking force according to the pedal command. The mechanical braking force is obtained by subtracting the regenerative braking force generated by the drive motor at that moment from the total braking force demand value calculated by the chassis domain controller according to the pedal command.

[0077] The mechanical braking force is controlled by the front axle electro-hydraulic braking system and the rear axle electro-mechanical braking system. The mechanical braking force is distributed to the front axle electro-hydraulic braking system and the rear axle electro-mechanical braking system to generate actual four-wheel mechanical braking force. When the road surface adhesion conditions are poor, the braking force applied to the wheel with a tendency to slip can be appropriately reduced to prevent the wheel from locking up, thus realizing the chassis controllable braking function.

[0078] As an optional implementation, in the absence of anti-lock braking system (ABS), when multiple failures occur in the first main braking unit, the second main braking unit, and the redundant braking unit, failing to meet the chassis braking deceleration requirements, the chassis domain controller controls the normally functioning parts of the first main braking unit, the second main braking unit, and the redundant braking unit, as well as the motor regenerative braking system. Specifically, this includes:

[0079] If multiple failures occur in the first main braking unit, the second main braking unit, and the redundant braking unit (e.g., the first main braking unit partially fails, the second main braking unit only fails in the left rear wheel, and the redundant braking unit only fails in the left half), the residual braking potential of the main and redundant braking units can be utilized. Control can be applied to the first main braking unit, the second main braking unit, and the redundant braking unit that can still generate some braking force; that is, braking commands are still issued to them even in the failed state, providing as much force as possible, supplemented by electric braking force. Under this extreme condition, the chassis domain controller will prioritize stopping the vehicle as quickly as possible, utilizing all available braking force sources to fully guarantee the emergency braking function and maximize the effectiveness of electric braking.

[0080] As an optional implementation, in the absence of anti-lock braking system (ABS), when the second main braking unit fails, the chassis domain controller controls the normally functioning smart tires among the left front wheel, right front wheel, left rear wheel, and right rear wheel smart tires, as well as the front axle-controlled steering system, according to pedal commands. Specifically, this includes:

[0081] Without anti-lock braking, when the second main braking unit fails, the chassis domain controller obtains mechanical braking force based on pedal commands.

[0082] The intelligent tires that are functioning normally among the left front wheel intelligent tire, right front wheel intelligent tire, left rear wheel intelligent tire, and right rear wheel intelligent tire are corrected based on the mechanical braking force.

[0083] Determine if there is a deviation between the current yaw rate of the chassis and the expected yaw rate.

[0084] If a deviation exists, the front axle steering system is controlled based on the deviation between the current yaw rate and the desired yaw rate.

[0085] If no deviation is found, the correction process ends.

[0086] Without anti-lock braking, when the second main braking unit fails, the chassis domain controller controls the normally functioning smart tires (left front, right front, left rear, and right rear) and the front axle-controlled steering system according to pedal commands. More specifically:

[0087] When the failure of the second master brake unit causes the left rear wheel brake to fail, considering road adhesion limitations, the total mechanical braking force is redistributed to the remaining three normal wheels while trying to meet the requirements. If a yaw rate deviation occurs during this process, the steering angle is corrected based on this deviation. Using PID control methods, after the mechanical braking force of the remaining three normal wheels has been redistributed, the yaw rate deviation of the vehicle body is input to obtain the corrected value for the front wheel steering angle. The front axle-controlled steering system intervenes to compensate for the yaw stability after the mechanical braking force redistribution. The same principle applies when the failure of the second master brake unit causes the right rear wheel brake to fail.

[0088] As an optional implementation, under anti-lock braking conditions, when the anti-lock braking system of the left front wheel smart tire or the right front wheel smart tire fails, the chassis domain controller adjusts the brake master cylinder pressure in the redundant braking unit, specifically including:

[0089] In anti-lock braking systems (ABS), when the ABS of the left or right front wheel fails, the brake wheel cylinder pressure cannot be adjusted independently, but the master cylinder pressure remains adjustable. The master cylinder pressure is corrected in real-time based on the wheel slip ratio control error, while simultaneously adjusting the wheel cylinder pressures of both front wheels, thus achieving redundant ABS braking on the front axle. This implementation process is existing technology and is commonly found in the redundant design of ABS functions in steerable hydraulic braking systems.

[0090] As an optional implementation, the pedal command can be an electrical signal command of the pedal in autonomous driving mode, or a real mechanical command in manned driving mode.

[0091] The present invention has the following technical effects:

[0092] This invention's chassis domain controller, as the core controller, is responsible for the integrated control of the intelligent electric chassis. It sends upper-level decision commands to lower-level controllers in the drive, braking, steering, and suspension subsystems for execution, while simultaneously collecting their real-time operating status information. It fully considers the comprehensive control of the chassis drive, braking, steering, and suspension subsystems under critical driving conditions, realizing chassis driving and road condition observation, integrated intelligent control of longitudinal, lateral, and vertical dynamics, comprehensive fault diagnosis of subsystem sensing and execution components, and fault-tolerant operation control of chassis failure under extreme conditions. The chassis domain controller itself features hardware redundancy design, including redundant control chips and redundant communication networks. The chassis domain controller integrates the minimum system for autonomous driving and the corresponding communication system. It interacts with the autonomous driving system at extreme dynamic control boundaries. The longitudinal, lateral, and vertical dynamic control of the chassis in the chassis domain controller supports both autonomous and manual driving, and smoothly transitions between the two. When the autonomous driving system fails, the chassis domain interacts with it to negotiate the fault degradation handling mode, takes over and assumes short-term safe driving functions, meets the safety requirements of the intelligent electric chassis under high-level autonomous driving conditions, optimizes the control objectives in both software and hardware, fundamentally solves the performance conflicts caused by the mutual coupling between subsystems, and achieves the optimal overall vehicle performance in terms of chassis drive, braking, steering, and vertical control.

[0093] This invention can meet the high-precision longitudinal and lateral vertical dynamic control and fault-tolerant control safety requirements of intelligent electric vehicle chassis under L3 and above autonomous driving conditions, making the overall performance of intelligent electric vehicles better in terms of safety, power, handling, stability, economy, etc.

[0094] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0095] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A smart electric chassis configuration, characterized in that, include: The chassis domain controller and the front axle centralized motor drive assembly, the rear axle distributed motor drive assembly, the front axle electro-hydraulic braking system, the rear axle electro-mechanical braking system, the front axle central steering system, the intelligent suspension system, the left front wheel intelligent tire, the right front wheel intelligent tire, the left rear wheel intelligent tire, and the right rear wheel intelligent tire, all connected to the chassis domain controller respectively. The front axle-controlled steering system includes two steering modules. Each steering module includes a steering control unit, a steering motor driver, and a steering motor connected in sequence. The steering control unit is connected to the chassis domain controller. The front axle centralized motor drive assembly includes: a centralized drive motor, a front wheel reducer, and a drive half shaft connected in sequence; The centralized drive motor is connected to the chassis domain controller, and the drive half-shaft is connected to the left front wheel smart tire and the right front wheel smart tire; the rear axle distributed motor drive assembly includes: a left rear wheel end drive motor and a left rear wheel reducer connected in sequence, and a right rear wheel end drive motor and a right rear wheel reducer connected in sequence; both the left rear wheel end drive motor and the right rear wheel end drive motor are connected to the chassis domain controller; the left rear wheel reducer is connected to the left rear wheel smart tire, and the right rear wheel reducer is connected to the right rear wheel smart tire; The front axle electro-hydraulic braking system includes a first main braking unit and a redundant braking unit; the rear axle electro-mechanical braking system includes a second main braking unit; the first main braking unit, the redundant braking unit, and the second main braking unit are all connected to the chassis domain controller. The chassis domain controller is used to control the centralized drive motor, the left rear wheel drive motor, the right rear wheel drive motor, the first main braking unit, the redundant braking unit, the second main braking unit, the front axle-controlled steering system, the intelligent suspension system, the left front intelligent tire, the right front intelligent tire, the left rear intelligent tire, and the right rear intelligent tire, respectively. In the absence of anti-lock braking, when the first main braking unit fails, the chassis domain controller controls the redundant braking unit of the front axle electro-hydraulic braking system to operate. When the second main braking unit fails, the chassis domain controller controls the normally functioning intelligent tires among the left front, right front, left rear, and right rear intelligent tires and the front axle-controlled steering system according to pedal commands. When multiple failures occur in the first main braking unit, the second main braking unit, and the redundant braking unit, failing to meet the chassis braking deceleration requirements, the chassis domain controller controls the normally functioning parts of the first main braking unit, the second main braking unit, and the redundant braking unit, as well as the regenerative braking system.

2. The intelligent electric chassis configuration according to claim 1, characterized in that, The front axle centralized motor drive assembly further includes a centralized drive motor controller, wherein the centralized drive motor is connected to the chassis domain controller via the centralized drive motor controller.

3. The intelligent electric chassis configuration according to claim 1, characterized in that, The rear axle distributed motor drive assembly further includes: a left rear wheel end drive motor controller and a right rear wheel end drive motor controller; the left rear wheel end drive motor is connected to the chassis domain controller through the left rear wheel end drive motor controller; the right rear wheel end drive motor is connected to the chassis domain controller through the right rear wheel end drive motor controller.

4. The intelligent electric chassis configuration according to claim 1, characterized in that, The left front wheel smart tire, the right front wheel smart tire, the left rear wheel smart tire, and the right rear wheel smart tire all include a tire body and an accelerometer, a strain gauge, a pressure sensor, and a signal transmission and processing module disposed within the tire body.

5. A fault-tolerant control method for an intelligent electric chassis, characterized in that, Applied to the intelligent electric chassis configuration of any one of claims 1-4, the method comprises: When the central drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor are all working normally, the chassis domain controller controls the central drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor according to the pedal command; When the left rear wheel drive motor or the right rear wheel drive motor fails, the chassis domain controller controls the normal motor and the front axle steering system based on the deviation between the current driving state and the desired driving state of the chassis. When the left rear wheel drive motor fails, the normal motor is the right rear wheel drive motor and the centralized drive motor. When the right rear wheel drive motor fails, the normal motor is the left rear wheel drive motor and the centralized drive motor. When the centralized drive motor fails, the chassis domain controller controls the left rear wheel drive motor and the right rear wheel drive motor according to the pedal command; When both the first and second main braking units are working normally, the chassis domain controller controls the front axle electro-hydraulic braking system and the rear axle electromechanical braking system according to the pedal command; specifically, when both the first and second main braking units are working normally, the chassis domain controller obtains mechanical braking force according to the pedal command; and controls the front axle electro-hydraulic braking system and the rear axle electromechanical braking system according to the mechanical braking force. Without anti-lock braking, when the first main braking unit fails, the chassis domain controller controls the redundant braking unit of the front axle electro-hydraulic braking system to operate; when the second main braking unit fails, the chassis domain controller controls the normally functioning smart tires among the left front wheel smart tire, right front wheel smart tire, left rear wheel smart tire, and right rear wheel smart tire, as well as the front axle-controlled steering system, according to pedal commands; when multiple failures occur in the first main braking unit, second main braking unit, and redundant braking unit, failing to meet the chassis braking deceleration requirements, the chassis domain controller controls the normally functioning parts of the first main braking unit, second main braking unit, and redundant braking unit, as well as the regenerative braking system. In anti-lock braking mode, when the anti-lock braking of the left front wheel smart tire or the right front wheel smart tire fails, the chassis domain controller adjusts the brake master cylinder pressure in the redundant braking unit.

6. The fault-tolerant control method for an intelligent electric chassis according to claim 5, characterized in that, When the centralized drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor are all operating normally, the chassis domain controller controls the centralized drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor according to the pedal command, specifically including: When the centralized drive motor, the left rear wheel end drive motor, and the right rear wheel end drive motor are all working normally, the chassis domain controller calculates the torque of the centralized drive motor, the torque of the left rear wheel end drive motor, and the torque of the right rear wheel end drive motor according to the pedal command. The centralized drive motor is controlled according to its torque; The left rear wheel drive motor is controlled according to the torque of the left rear wheel drive motor. The right rear wheel drive motor is controlled according to the torque of the right rear wheel drive motor.

7. The fault-tolerant control method for an intelligent electric chassis according to claim 5, characterized in that, When the left rear wheel drive motor or the right rear wheel drive motor fails, the chassis domain controller controls the normal motor and the front axle steering system based on the deviation between the current driving state and the desired driving state of the chassis. Specifically, this includes: When the left rear wheel drive motor or the right rear wheel drive motor fails, the chassis domain controller corrects the torque of the normal motor based on the deviation between the current driving state and the desired driving state of the chassis. Determine whether the current driving state has reached the desired driving state; If the desired driving state is not achieved, the steering angle of the front axle-controlled steering system is corrected based on the deviation between the current driving state and the desired driving state. If the condition is met, the correction process ends.

8. The fault-tolerant control method for an intelligent electric chassis according to claim 5, characterized in that, Without anti-lock braking, when the second master braking unit fails, the chassis domain controller controls the normally functioning smart tires (left front, right front, left rear, and right rear) and the front axle-controlled steering system according to pedal commands. Specifically, this includes: Without anti-lock braking, when the second main braking unit fails, the chassis domain controller obtains mechanical braking force based on pedal commands; The mechanical braking force is used to correct the working smart tire among the left front wheel smart tire, right front wheel smart tire, left rear wheel smart tire and right rear wheel smart tire; Determine if there is a deviation between the current yaw rate of the chassis and the expected yaw rate; If a deviation exists, the front axle steering system is controlled based on the deviation between the current yaw rate and the desired yaw rate. If no deviation is found, the correction process ends.

Images