Prototype vehicle development test platform for drive-by-wire technology test

Abstract

The invention discloses a prototype vehicle development test platform for a drive-by-wire technology test, relates to the technical field of vehicle drive-by-wire technology / automobile chassis control, and aims to provide the prototype vehicle development test platform for the drive-by-wire technology test, which is high in integration level, capable of realizing cooperative control, high in expandability, reasonable in redundancy design and controllable in cost. The defects in the prior art are overcome. The technical key points are as follows: the platform comprises an upper computer, a vehicle control unit, a drive-by-wire steering system, a drive-by-wire braking system, a drive-by-wire driving system, a sensor module, a communication module and an electrical device. The upper computer monitors the running states of all the systems and the whole vehicle in real time, records data and visually displays the data, and assists algorithm optimization and development testing. The whole vehicle controller serves as a core control unit and coordinates work of all subsystems, and whole vehicle control strategy testing is achieved. The sensor module integrates a tension and pressure sensor, a dynamic torque sensor, a gyroscope, an IMU and the like to monitor the running state of the vehicle in real time, and provides state variable information needed by the system. The core of the invention lies in constructing an integrated test environment for collaborative test and development of each subsystem of the drive-by-wire vehicle.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control-by-wire technology / automobile chassis control technology, and in particular to a prototype vehicle development test platform for controlling-by-wire technology testing. Background Art

[0002] By-wire chassis technology is a core foundation for the development of intelligent driving and new energy vehicles, and the demand for experimental verification platforms is growing. Existing technologies often focus on a single subsystem (such as steer-by-wire or brake-by-wire) or rely on retrofitting some systems in existing vehicles. These platforms suffer from low integration, poor functional scalability, insufficient redundancy, and high costs. Furthermore, test structures that are not complete vehicles struggle to simulate real-world road conditions, failing to provide drivers with authentic and effective road feel feedback.

[0003] Analysis of existing literature:

[0004] 1. Existing Patent Documents: Invention patent CN119037307A (Proton Automotive Technology, publication date: November 2024) proposes a drive-by-wire chassis electrical architecture that distributes network traffic through multiple communication buses to reduce overall network load. Its drawbacks include: it only distributes communications within the electrical architecture of each chassis system, lacking coordinated optimized control of the drive system, brake-by-wire, and steer-by-wire. Furthermore, it lacks a platform's mechanical architecture and lacks the application positioning of a "drive-by-wire chassis development platform."

[0005] 2. Existing patent documents Invention patent CN112133153A (Cool Black Intelligent Driving Technology (Beijing) Co., Ltd., publication date: December 2020) proposes a teaching and training platform for a wire-controlled chassis for unmanned vehicles and its use method. Through modular design and function expansion interfaces, the basic functions of the wire-controlled chassis are realized in teaching and training scenarios, providing a flexible and efficient teaching platform that can meet the diverse teaching needs of courses related to unmanned vehicles, while supporting scientific research and testing. Its defects are: although it integrates wire-controlled steering, braking, and driving, it does not clearly explain the real-time collaborative control of multiple subsystems, such as the independent torque distribution of the hub motor and the steering or braking adjustment; the existing patent integrates the wire-controlled system into modules to build a teaching platform, which is not a complete vehicle development platform. It cannot realize the driver mode and cannot conduct control strategy research for human-machine co-driving. For some control algorithms, such as road feel feedback, it is impossible to feel the "road feel" from the driver's perspective. At the same time, the testable working conditions are limited by the platform.

[0006] 3. Patent document CN 117516966 A (China FAW Group Corporation, publication date: February 2024) proposes a driving simulator and steer-by-wire hardware-in-the-loop system test platform and method. This platform establishes a combined driving simulator and steer-by-wire HIL simulation test platform, enabling closed-loop human-vehicle-road control testing through the driving simulator system. However, its drawbacks include insufficient integration, focusing on a single subsystem (steer-by-wire), and lacking the ability to coordinate full-wire control (steering, braking, and actuation).

[0007] It can be seen that the existing test structure is difficult to simulate real road excitation, cannot provide the driver with real and effective road feel feedback, and cannot perform system tests of wire-controlled steering, wire-controlled braking, wire-controlled drive, wire-controlled suspension, and coordinated control tests of various wire-controlled systems of the entire vehicle. Summary of the Invention

[0008] The technical problems to be solved by the present invention are:

[0009] The present invention aims to provide a prototype vehicle development test platform for drive-by-wire technology testing with high integration, collaborative control, strong scalability, reasonable redundancy design and controllable cost, so as to overcome the shortcomings of the existing technology.

[0010] The technical solution adopted by the present invention to solve the above technical problems is:

[0011] A prototype vehicle development test platform for testing drive-by-wire technology, characterized in that the platform includes a host computer, a vehicle control unit (VCU), a steer-by-wire system, a brake-by-wire system, a drive-by-wire system, a sensor module, a communication module, and electrical components;

[0012] The host computer monitors the operating status of each system (steer-by-wire system, brake-by-wire system, and drive-by-wire system) and the vehicle in real time, records data and displays it visually, and assists in algorithm optimization and development testing (i.e., optimization and development testing of the algorithm being tested);

[0013] The vehicle controller unit (VCU) serves as the core control unit, coordinating the operation of various systems (steer-by-wire, brake-by-wire, and drive-by-wire) to implement vehicle control strategy testing. It has multiple input and output interfaces, including analog input, switch output, and channel communication interfaces, and is compatible with multiple communication protocols such as CAN and LIN.

[0014] The communication module is responsible for data transmission between the wire-controlled steering system, wire-controlled braking system, wire-controlled drive system, wire-controlled suspension system and the VCU and host computer; the communication module adopts CAN protocol communication and contains five CAN channels. The control units of different wire-controlled functions are connected to different communication buses respectively. On the one hand, it ensures the real-time and reliability of signal transmission, and on the other hand, it effectively reduces channel utilization and improves communication speed and quality; the first channel is used as the calibration CAN and the program burning interface. At the same time, the parameters defined in the model can be calibrated and tested online through the host computer software. The second channel is the communication bus of the two dual-motor drivers in the wire-controlled drive system to drive the front and rear wheel hub motors. The third channel is responsible for the steering execution controller, steering feedback controller, and wire-controlled brake controller in the wire-controlled steering system. The fourth channel is responsible for gyroscope signal processing and remote control signal reception. The fifth channel is the communication interface of the wire-controlled suspension system to facilitate subsequent program development.

[0015] The main hardware of the wire-controlled steer-to-wire system includes a steering wheel assembly and a steering actuator assembly. The steering wheel assembly includes a steering wheel, a steering wheel angle sensor, a road feel feedback motor, and a torque sensor. The steering actuator assembly includes a steering motor controller, a steering actuator, and a tension and pressure sensor. The steering wheel is used to receive steering manipulations from the driver and transmit feedback of road feel to the driver. The angle sensor measures the steering wheel angle (in this invention, a servo motor encoder can also be used to feedback the steering wheel angle signal to the VCU). The road feel feedback motor and integrated reduction mechanism provide the driver with road feel information feedback under different control strategies and output the steering wheel return torque. The torque sensor measures the actual torque output by the road feel motor and provides state variable information for the control strategy. The steering motor controller controls the working state of the steering actuator motor, which is responsible for driving the steering rod to drive the wheels to rotate. The tension and pressure sensor feedbacks the tension and pressure signals of the steering rod. The test modes of the wire-controlled steer-to-wire system are divided into driver mode and remote control mode. In driver mode, the driver rotates the steering wheel, and the angle sensor and torque sensor in the system monitor in real time and convert the steering wheel angle and torque signals into electrical signals (in remote control mode, the VCU directly receives the remote steering signal).

[0016] The main hardware of the wire control brake system includes the brake pedal, pedal displacement sensor (the brake pedal and pedal displacement sensor are integrated into a brake signal pedal), wheel speed sensor, EHB controller, EHB brake actuator, master cylinder pressure sensor, four-wheel calipers and brake discs; the test mode of the wire control brake system is also divided into driver mode and remote control mode. In driver mode, when the driver steps on the brake pedal, the pedal displacement sensor converts the displacement signal into an analog electrical signal and transmits it to the VCU through the CAN bus (in remote control mode, the VCU directly receives the remote braking signal); at the same time, the VCU receives the wheel speed signal from the wheel speed sensor, integrates the vehicle's driving status and the driver's braking intention, analyzes and processes the signal according to the control strategy to be tested, calculates the braking force required for each wheel, and sends it to the EHB controller in the form of a CAN signal to drive the actuator to brake the vehicle; at the same time, the sensor will feedback the real-time master cylinder braking force, the angle and speed of the actuator motor, and the wheel speed to the VCU to complete the system closed loop.

[0017] The main hardware components of the drive-by-wire system include an accelerator pedal, a pedal displacement sensor (the accelerator pedal and pedal displacement sensor are integrated into a throttle signal pedal), a front-wheel dual-motor driver, a rear-wheel dual-motor driver, and four-wheel hub motors. The drive-by-wire system's test modes are also divided into driver mode and remote control mode. In driver mode, when the driver presses the accelerator pedal, the pedal displacement sensor converts the displacement signal into an analog electrical signal and transmits it to the VCU via the CAN bus. (In remote control mode, the VCU directly receives the remote acceleration signal.) At the same time, the VCU comprehensively analyzes the vehicle status information sent by the sensor module, combines the tested control algorithm and differential steering strategy to calculate the required motor torque and speed for the four wheels, and generates corresponding control commands. These commands are sent via the bus to the front-wheel dual-motor driver and the rear-wheel dual-motor driver (in-wheel motor driver). The dual-motor driver and the rear-wheel dual-motor driver convert the commands into motor drive signals to control the operation of the in-wheel motors and achieve vehicle acceleration or deceleration. At the same time, the Hall effect sensor and photoelectric encoder sensor in the in-wheel motor monitor the motor rotor position and speed in real time and feed them back to the VCU, forming a closed-loop control loop to ensure that the motor operation is in line with the driver's intention. Figure 1 To;

[0018] The sensor module integrates a tension and pressure sensor, a dynamic torque sensor, a gyroscope, an IMU, a speed sensor, and a yaw rate sensor. It monitors the vehicle's operating status in real time and provides state variable information required by the system (referring to the steer-by-wire system, brake-by-wire system, and drive-by-wire system). The sensor module transmits the collected vehicle status signals to the VCU. After receiving signals from various sensors, the VCU processes and analyzes these signals according to the algorithm and logic under test (involving the content of the algorithm under test). By comprehensively considering the driver's steering intention, the vehicle's current motion state, and road conditions, it determines the required steering response and generates corresponding control commands. These are transmitted via the CAN protocol. CAN signals are sent to the steering actuator (including the steering actuator motor) to drive the steering wheels to rotate in the desired direction and angle, thereby implementing the driver's steering intention. Torque commands are also sent to the road feedback motor, causing it to generate the corresponding feedback torque, providing the driver with real-time road feedback.

[0019] The electrical device ( Figure 2 ) includes multiple groups of DCDCs, which are used to convert the high voltage output by the battery pack into a low voltage to power the low-voltage system (such as the wire-controlled steering system, wire-controlled braking system, and wire-controlled suspension system), and the high-voltage system (such as the wire-controlled drive system) is directly powered by the battery. The electrical components also include contactors, start switches, emergency stop switches, fuses, and distributors for ensuring the smooth and safe operation of the electrical system and the entire vehicle system. The installation positions of the contactors, start switches, emergency stop switches, fuses, and distributors and the surrounding connection relationships are within the scope of the existing technology.

[0020] The platform also includes a suspension-by-wire system. The communication module is responsible for data transmission between the suspension-by-wire system and the VCU and host computer. The suspension-by-wire system is a parallel system to the steering-by-wire system, brake-by-wire system, and drive-by-wire system. These systems exchange information with the host computer and are controlled by the vehicle control unit (VCU).

[0021] In addition to enabling independent control testing of each drive-by-wire system, the platform can also develop and test coordinated control strategies for all drive-by-wire chassis systems and provide a control development interface for the drive-by-wire suspension. The drive-by-wire steering, brake-by-wire, drive-by-wire, and suspension-by-wire systems achieve information exchange and collaborative control through the vehicle control unit.

[0022] The VCU collects vehicle status and driver intention (or remote control signal) in real time, and sends control instructions to each subsystem after comprehensive analysis according to a given collaborative strategy to optimize the vehicle's target performance.

[0023] The platform can achieve multiple vehicle performance objectives and multi-system coordinated control. Through optimization algorithms, it can optimize the coordinated control design of various chassis subsystems, coordinate the coupling of various chassis subsystems, reduce conflicts between systems, and improve handling stability and braking efficiency.

[0024] During emergency braking, the wire control brake system responds to the brake pedal signal, the wire control steering system adjusts the steering assist, the wire control drive system adjusts the power output, and the wire control suspension system adjusts the shock absorber damping to jointly maintain vehicle stability.

[0025] The present invention has the following beneficial technical effects:

[0026] This invention is a test platform capable of conducting system testing of by-wire steering, by-wire braking, by-wire drive, and by-wire suspension, as well as collaborative control testing of all by-wire systems within a vehicle. The test development platform, designed for a complete vehicle prototype, enables real-vehicle testing of the fully by-wire chassis, including two test modes: driver mode and remote control mode. This system can acquire and store various sensor signals within the by-wire system, develop control algorithms and collaborative control strategies, and perform test procedures. It also provides an open program interface for subsequent functional and algorithm expansion.

[0027] This invention can implement hardware testing, algorithm testing, and program development for the vehicle chassis's wire-controlled steering, wire-controlled braking, wire-controlled drive, and wire-controlled suspension systems. It boasts high integration and low cost. The invention can conduct coordinated control testing of each of the chassis' wire-controlled systems, providing a program interface for testing and verifying different coordinated control strategies. The invention offers two testing methods: driver mode and remote control mode, which provide high redundancy. Furthermore, the invention is a prototype vehicle for a wire-controlled chassis, possessing the integrity of the entire vehicle while being small and low-cost. Field testing is possible, allowing the driver to subjectively experience road feedback and vehicle status under different control strategies. Comparative studies between simulated and actual vehicle operating conditions under different control strategies can be conducted. This invention is applicable to the testing and development of vehicle wire-controlled technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic block diagram of the structure of the wire control platform of the present invention. Figure 2 This is the electrical architecture diagram of the wire-controlled chassis platform. Figure 3 The structural diagram of the wire-controlled platform vehicle prototype (the three-dimensional model of the wire-controlled platform vehicle prototype); Figure 4 These are photos of the actual car with the wire control platform. DETAILED DESCRIPTION

[0029] The platform of the present invention includes a host computer, a vehicle control unit (VCU), a wire-controlled steering system, a wire-controlled braking system, a wire-controlled drive system, a sensor module, a communication module and electrical devices.

[0030] The host computer monitors the operating status of each system and the entire vehicle in real time, records data and displays it visually, and assists in algorithm optimization and development testing.

[0031] The vehicle controller unit (VCU) serves as the core control unit, coordinating the operations of various subsystems and implementing vehicle control strategy testing. It features multiple input and output interfaces, including analog inputs, digital outputs, and communication interfaces for each channel, and is compatible with various communication protocols such as CAN and LIN.

[0032] The sensor module integrates tension and pressure sensors, dynamic torque sensors, gyroscopes, IMUs, etc. to monitor the vehicle's operating status in real time and provide the state variable information required by the system.

[0033] The communication module is responsible for data transmission between subsystems, between subsystems and VCU and host computer. The present invention adopts CAN protocol communication, including five channels of CAN. The control units of different wire control functions are connected to different communication buses respectively. On the one hand, it ensures the real-time and reliability of signal transmission, and on the other hand, it effectively reduces channel utilization and improves communication speed and quality. The first channel serves as a calibration CAN and a program burning interface. At the same time, the parameters defined in the model can be calibrated and tested online through the host computer software. The second channel is the communication bus of two dual-motor drivers to drive the front and rear wheel hub motors. The third channel is responsible for the steering execution controller, steering feedback controller, and wire control brake controller. The fourth channel is responsible for signal processing of the gyroscope module and reception of remote control signals. The fifth channel is the communication interface of the wire control suspension, which is convenient for subsequent program development.

[0034] The main hardware of the steer-by-wire system includes the steering wheel assembly (steering wheel, steering wheel angle sensor, road feel feedback motor, torque sensor); and the steering actuator assembly (steering motor controller, steering actuator, and tension and pressure sensor). The steering wheel receives steering inputs from the driver and transmits road feel feedback to the driver. The angle sensor measures the steering wheel angle (in this invention, a servo motor encoder can also be used to feed steering wheel angle signals to the VCU). The road feel feedback motor and integrated reduction mechanism provide the driver with road feel information under different control strategies and output the steering wheel return torque. The torque sensor measures the actual torque output by the road feel motor, providing state variable information for the control strategy. The steering motor controller controls the operating state of the steering actuator motor, which drives the steering rod to drive the wheels. The tension and pressure sensor provides feedback on the tension and pressure signals of the steering rod. The steer-by-wire system has two test modes: driver mode and remote control mode. In driver mode, the driver rotates the steering wheel, and the system's angle sensor and torque sensor monitor the steering wheel angle and torque signals in real time, converting them into electrical signals. (In remote control mode, the VCU directly receives the remote steering signal.) At the same time, vehicle status signals collected by the speed sensor, yaw rate sensor, and other sensors are transmitted to the VCU. After receiving signals from various sensors, the VCU processes and analyzes them using pre-set algorithms and logic. Taking into account factors such as the driver's steering intent, the vehicle's current motion state, and road conditions, it determines the required steering response and generates corresponding control commands, which are transmitted via the CAN protocol. These commands send CAN signals to the steering actuator motor to drive the steering wheels in the desired direction and angle, thereby fulfilling the driver's steering intent. Furthermore, torque commands are sent to the road sensor motor, causing it to generate the corresponding feedback torque, providing the driver with real-time road feel feedback.

[0035] The primary hardware of the brake-by-wire system includes the brake pedal, pedal displacement sensor (the brake pedal and pedal displacement sensor are integrated into a brake signal pedal), wheel speed sensors, EHB controller, EHB brake actuator, master cylinder pressure sensor, four-wheel calipers, and brake discs. The brake-by-wire system can be tested in either driver mode or remote control mode. In driver mode, when the driver depresses the brake pedal, the pedal displacement sensor converts the displacement signal into an analog electrical signal and transmits it to the VCU via the CAN bus. (In remote control mode, the VCU directly receives the remote brake signal.) Simultaneously, the VCU receives wheel speed signals from the wheel speed sensors, analyzes and processes them based on the vehicle's driving state and the driver's braking intent, and calculates the required braking force for each wheel. This signal is then sent to the EHB controller as a CAN signal, which in turn drives the actuator to brake the vehicle. Simultaneously, the sensors provide the VCU with real-time feedback on the master cylinder braking force, the actuator motor's rotational angle and speed, and the wheel speed, completing the system's closed-loop.

[0036] The primary hardware components of the drive-by-wire system include an accelerator pedal, a pedal displacement sensor (the accelerator pedal and pedal displacement sensor are integrated into a throttle signal pedal), a front-wheel dual-motor driver, a rear-wheel dual-motor driver, and four-wheel hub motors. The drive-by-wire system's test modes are divided into driver mode and remote control mode. In driver mode, when the driver presses the accelerator pedal, the pedal displacement sensor converts the displacement signal into an analog electrical signal and transmits it via the CAN bus to the VCU. (In remote control mode, the VCU directly receives the remote acceleration signal.) Simultaneously, the VCU receives signals from other sensors, such as vehicle speed. The VCU analyzes these signals, combining preset control logic and differential steering strategies to calculate the required motor torque and speed for all four wheels and generate corresponding control commands. These commands are sent via the bus to the hub motor drivers, which convert them into motor drive signals, controlling the hub motors to accelerate or decelerate the vehicle. Simultaneously, the Hall effect sensors and photoelectric encoder sensors within the hub motors monitor the motor rotor position and speed in real time, feeding this information back to the ECU, forming a closed-loop control system that ensures motor operation aligns with the driver's intent. Figure 1 To.

[0037] In addition to achieving independent control testing of each wire-controlled system, the present invention can also achieve the development and testing of coordinated control strategies for all systems of the fully wire-controlled chassis. The present invention provides a control development interface for the wire-controlled suspension. The wire-controlled steering, wire-controlled braking, wire-controlled drive, and wire-controlled suspension systems achieve information exchange and collaborative control through the vehicle control unit. The VCU collects vehicle status and driver intent (or remote control signals) in real time, and after comprehensive analysis based on a given collaborative strategy, sends control instructions to each subsystem to optimize the vehicle's target performance. This can achieve vehicle multi-performance objectives and multi-system collaborative control design. Through optimization algorithms, the coordinated control optimization design of each chassis subsystem is performed, the coupling of each chassis subsystem is coordinated, conflicts between systems are reduced, and handling stability and braking efficiency are improved. For example, during emergency braking, the wire-controlled brake system responds to the brake pedal signal, the wire-controlled steering system adjusts the steering assist, the wire-controlled drive system adjusts the power output, and the wire-controlled suspension system adjusts the shock absorber damping to jointly maintain vehicle stability.

[0038] Example 1:

[0039] Give Attachment Figure 1-4 The following describes the implementation of a prototype vehicle development test platform for drive-by-wire technology testing according to the present invention:

[0040] Attachment Figure 1It is a schematic diagram of a drive-by-wire platform. The present invention relates to a drive-by-wire test and development platform, the core of which is to build an integrated test environment for the collaborative testing and development of various subsystems of drive-by-wire vehicles. The platform uses a drive-by-wire prototype vehicle as a platform, is equipped with a vehicle controller VCU as a core control unit, and realizes efficient communication and control with subsystems such as drive-by-wire, brake-by-wire, drive-by-wire, and suspension-by-wire through the CAN bus. In this invention, the first channel serves as a calibration CAN and a program burning interface, and at the same time, the parameters defined in the model can be calibrated and tested online through the host computer software; the second channel is the communication bus for drive-by-wire, which is responsible for the communication between the two dual-motor drivers to drive the front and rear wheel hub motors; the third channel is the communication bus for steering-by-wire and brake-by-wire, which is responsible for conveying and receiving commands and signals from the steering execution controller, steering feedback controller, and brake-by-wire controller; the fourth channel is responsible for signal processing of the gyroscope module, battery feedback, and reception of remote control signals; the fifth channel is the communication interface for the control-by-wire suspension, which is convenient for subsequent program development and testing. At the same time, the platform includes a host computer and a display screen. It uses a multi-channel CAN adapter to visually monitor and record vehicle operation data through the CAN bus, and calibrate and program the VCU control strategy.

[0041] In addition, the platform also integrates a signal acquisition and conversion module, an SBUS to CAN module for processing remote control receiver signals, a gyroscope module for providing vehicle dynamic information, and a battery feedback system for monitoring and providing feedback on battery charge and voltage, ensuring a stable power supply for the entire platform. The platform's vehicle controller can control the switch quantity (this invention is a 24V switch quantity). Switch quantity signal 1 corresponds to KM1, switch quantity signal 2 corresponds to KM2, and switch quantity signal 3 corresponds to the power warning buzzer. The VCU can receive remote control signals to control the opening and closing of contactors KM1 and KM2. Based on the battery feedback signal, the VCU determines the battery's operating status according to a preset program. When the battery charge is lower than the preset value, the power warning buzzer is triggered.

[0042] The platform's vehicle controller can receive multi-channel analog signals. Analog signal line 1 corresponds to the two steering rod tension and pressure sensors, analog signal line 2 corresponds to the dynamic torque sensor, and analog signal line 3 corresponds to the accelerator and brake pedals. The accelerator and brake pedals in the prototype vehicle directly convert the driver's displacement signals into 0-5V analog signals and transmit them to the VCU. The left steering rod tension and pressure sensor converts the tension and pressure signals into 0-5V analog signals via transmitter 1 and transmits them to the VCU. The right steering rod tension and pressure sensor converts the tension and pressure signals into 0-5V analog signals via transmitter 2 and transmits them to the VCU. The dynamic torque sensor converts the torque signals into 0-5V analog signals via transmitter 3 and transmits them to the VCU.

[0043] Attachment Figure 2 This is the overall electrical architecture of the drive-by-wire chassis platform. The vehicle's power supply system is a 48V ternary lithium battery pack. The vehicle has a low-voltage rocker switch (SB0), a start switch (SB1), and two emergency stop switches (SB2 and SB3). When the vehicle starts, SB2 and SB3 are required to pop out, and SB0 and SB1 are closed. To perform an emergency stop, press either SB2 or SB3 to stop the vehicle. The VCU is connected to KM1 via 24V switch 1 and KM2 via 24V switch 2. After the vehicle is powered on, a remote control transmits a command to the VCU, closing KM1 and KM2 to power the drive and steering systems. 24V switch 3 controls the battery warning buzzer.

[0044] The power battery pack converts 48V voltage to 24V, 12V, and 20V voltages via four DC-DC converters to meet the needs of various devices. The 48V battery powers the front and rear dual-motor drives, brake control unit, DC-DC 48-12V, and DC-DC 48-24V. The DC-DC 48-24V supplies the vehicle control unit (VCU), DC-DC 24-20V, tension and pressure signal transmitters 1 and 2, gyroscope module, torque signal transmitter, and drive-by-wire feedback controllers 1 and 2. The DC-DC 48-12V supplies power to the steering actuator controller, brake-by-wire controllers 1 and 2, and the DC-DC 24-20V supplies power to the host computer. The VCU also provides 5V power: 5V power supply 1 powers the remote control receiver, 5V power supply 2 powers the accelerator pedal, 5V power supply 3 powers the brake pedal, and 5V power supply 4 powers the steering feedback encoder.

[0045] ① Splitter 1 is a 48V splitter with one input and eight outputs; ② Splitter 2 is a 12V splitter with one input and four outputs; ③ Splitter 3 is a 24V splitter with one input and nine outputs; and ④ Splitter 4 is a 24V splitter with one input and four outputs. Splitter units are used to separate wires from the main wiring harness into multiple branches for connection to various electrical devices and sensors. This helps optimize wiring layout, reduces the number and complexity of wiring harnesses, and improves system reliability and maintainability.

[0046] Attachment Figure 3 This is a 3D model of the prototype of the wire-controlled platform vehicle. Figure 4 For the real car.

[0047] Example 2:

[0048] The wire control platform has two test modes: driver mode and remote control mode.

[0049] Take the brake-by-wire test conditions in driver mode as an example: Before actual vehicle testing, the preset brake-by-wire control strategy is first programmed into the VCU using host computer software. After parameter calibration is complete and sensor filter signals are normal, the system is tested on site. Emergency stop switches SB2 and SB3 are popped out, SB0 and SB1 are closed, and the display opens to display the required signal curves, vehicle speed, and voltage signal windows for real-time observation and subsequent data storage. After the vehicle is powered on, a command is transmitted to the VCU via the remote control, closing KM1 and KM2 to power the drive and steering systems. The driver steers the vehicle at the target speed under specific road conditions and then applies the brake pedal along the preset brake line. The brake pedal converts the displacement signal into an electrical signal, which is transmitted to the VCU via the CAN bus. Simultaneously, the VCU receives signals from sensors such as wheel speed sensors and gyroscopes. Based on the vehicle's driving state and the driver's braking intent, it calculates the required braking force for each wheel according to the preset brake-by-wire control strategy. The VCU transmits the control command in the form of a CAN message to the brake-by-wire controller, which then controls the brake actuator to adjust the master cylinder pressure, achieving vehicle braking. This process can simulate emergency braking in real driving conditions, providing actual data support for the optimization of control strategies. At the same time, the driver can subjectively experience the braking performance and stability of the vehicle under different control strategies.

[0050] In addition, when emergency braking is performed under complex conditions at high speeds, the required vehicle motion conditions can be programmed into the VCU. The tester only needs to move the preset joystick on the remote control, and the test vehicle will be able to drive according to the specified conditions and complete braking. The host computer can record real-time data.

[0051] In the collaborative control strategy, let's take vehicle stability control under different road conditions as an example. When driving on slippery roads, the VCU determines the possibility of the vehicle slipping based on vehicle status signals collected by wheel speed sensors, yaw rate sensors, and other sensors. At this point, the VCU coordinates the brake-by-wire system to individually brake the slipping wheel. Simultaneously, the drive-by-wire system adjusts power output to distribute more torque to wheels with traction. The steer-by-wire system adjusts steering assist based on vehicle dynamics, and the suspension-by-wire system adjusts shock absorber damping and spring rate to improve vehicle grip and stability. During implementation, multiple tests on roads of varying slipperiness optimized the parameters and logic of the collaborative control strategy, ensuring better vehicle stability on slippery roads and reducing the risk of loss of control.

[0052] Replacement structure of key parts:

[0053] In the sensor module, for example, the torque sensor in the steering system can be used. In addition to traditional torque sensors, magnetoelectric torque sensors can also be used. In implementation, the magnetoelectric torque sensor is installed on the steering shaft between the steering wheel and the steering actuator. The torque signal is converted into a 0-5V analog signal via appropriate signal processing circuitry and transmitted to the VCU, enabling precise monitoring of steering torque. Other sensors can be replaced with sensors of varying structural principles, as long as they can capture the required vehicle signals. In the actuators of the brake-by-wire system, in addition to hydraulic brake actuators, electric brake actuators can also be used. Electric brake actuators use a motor to drive the brake caliper to clamp the brake disc, achieving vehicle braking. Drive-by-wire suspension systems can utilize structures such as CDC electromagnetic dampers and magnetorheological dampers.

[0054] It has been verified that the test platform proposed in the present invention solves the technical problem proposed in the present invention, and the method described in the present invention has been verified through experiments and practical applications to achieve the technical effect claimed by the present invention.

[0055] Although the present disclosure is disclosed as above, the scope of protection of the present disclosure is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present disclosure. As long as they can achieve the desired results of the technical solutions disclosed in this application, these changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A prototype vehicle development test platform for testing drive-by-wire technology, characterized in that: The platform includes a host computer, a vehicle controller (VCU), a wire-controlled steering system, a wire-controlled braking system, a wire-controlled drive system, a sensor module, a communication module, and electrical components; The host computer monitors the operating status of each system and the entire vehicle in real time, records data and displays it visually, assisting in algorithm optimization and development testing; The vehicle controller (VCU) serves as the core control unit, coordinating the work of various systems and implementing vehicle control strategy testing. It has multiple input and output interfaces, including analog input, switch output, and various channel communication interfaces, and is compatible with CAN and LIN communication protocols. The communication module is responsible for data transmission between the wire-controlled steering system, wire-controlled braking system, wire-controlled drive system, wire-controlled suspension system and the VCU and host computer; the communication module adopts CAN protocol communication and contains five CAN channels. The control units of different wire-controlled functions are connected to different communication buses respectively. On the one hand, it ensures the real-time and reliability of signal transmission, and on the other hand, it effectively reduces channel utilization and improves communication speed and quality; the first channel is used as the calibration CAN and the program burning interface. At the same time, the parameters defined in the model can be calibrated and tested online through the host computer software. The second channel is the communication bus of the two dual-motor drivers in the wire-controlled drive system to drive the front and rear wheel hub motors. The third channel is responsible for the steering execution controller, steering feedback controller, and wire-controlled brake controller in the wire-controlled steering system. The fourth channel is responsible for gyroscope signal processing and remote control signal reception. The fifth channel is the communication interface of the wire-controlled suspension system to facilitate subsequent program development. The main hardware of the steer-by-wire system includes the steering wheel assembly and the steering actuator assembly. The steering wheel assembly includes the steering wheel, steering wheel angle sensor, road feel feedback motor, and torque sensor. The steering actuator assembly includes the steering motor controller, steering actuator, and tension and pressure sensors. The steering wheel is used to receive the driver's steering control and transmit road feel feedback to the driver. The angle sensor measures the steering wheel angle. The road feel feedback motor and integrated reduction mechanism provide the driver with road feel feedback under different control strategies and output the steering wheel's return torque. The torque sensor measures the actual torque output by the road-sensing motor and provides state variable information for the control strategy; The steering motor controller controls the operating status of the steering actuator motor, which drives the steering rod to rotate the wheels. The pull-pressure sensor provides feedback on the pull-pressure signal of the steering rod. The steer-by-wire system has two test modes: driver mode and remote control mode. In driver mode, the driver turns the steering wheel, and the system's angle sensor and torque sensor monitor the system in real time, converting the steering wheel angle and torque signals into electrical signals. The main hardware of the wire control brake system includes brake pedal, pedal displacement sensor, wheel speed sensor, EHB controller, EHB brake actuator, master cylinder pressure sensor, four-wheel calipers and brake discs; the test mode of the wire control brake system is also divided into driver mode and remote control mode. In driver mode, when the driver steps on the brake pedal, the pedal displacement sensor converts the displacement signal into an analog electrical signal and transmits it to the VCU through the CAN bus (in remote control mode, the VCU directly receives the remote braking signal); at the same time, the VCU receives the wheel speed signal from the wheel speed sensor, integrates the vehicle's driving status and the driver's braking intention, analyzes and processes the signal according to the control strategy to be tested, calculates the braking force required for each wheel, and sends it to the EHB controller in the form of a CAN signal to drive the actuator to brake the vehicle; at the same time, the sensor will feedback the real-time master cylinder braking force, the angle and speed of the actuator motor, and the wheel speed to the VCU to complete the system closed loop. The main hardware components of the wire-controlled drive system include an accelerator pedal, a pedal displacement sensor, a front-wheel dual-motor driver, a rear-wheel dual-motor driver, and four-wheel hub motors; the test modes of the wire-controlled drive system are also divided into driver mode and remote control mode. In driver mode, when the driver steps on the accelerator pedal, the pedal displacement sensor converts the displacement signal into an analog electrical signal and transmits it to the VCU via the CAN bus; at the same time, the VCU comprehensively analyzes the vehicle status information sent by the sensor module, and calculates the required motor torque and speed of the four wheels in combination with the tested control algorithm and differential steering strategy, and generates corresponding control instructions; the instructions are sent to the front-wheel dual-motor driver and the rear-wheel dual-motor driver via the bus, and the dual-motor driver and the rear-wheel dual-motor driver convert the instructions into motor drive signals to control the operation of the hub motors and realize vehicle acceleration or deceleration; at the same time, the Hall sensor and photoelectric encoder sensor in the hub motor monitor the motor rotor position and speed in real time, and feed it back to the VCU to form a closed-loop control to ensure that the motor operation is consistent with the driver's intention; The sensor module integrates tension and pressure sensors, dynamic torque sensors, gyroscopes, IMUs, vehicle speed sensors, and yaw rate sensors to monitor the vehicle's operating status in real time and provide the state variable information required by the system. The sensor module is used to transmit the collected vehicle status signals to the VCU. After receiving signals from various sensors, the VCU processes and analyzes these signals according to the measured algorithms and logic. By comprehensively considering the driver's steering intention, the vehicle's current motion state, and road conditions, it determines the steering response required by the vehicle and generates corresponding control instructions, which are transmitted through the CAN protocol. On the one hand, CAN signals are sent to the steering actuator to drive the steering wheels to rotate in the expected direction and angle, thereby realizing the driver's steering intention. On the other hand, torque commands are sent to the road feel feedback motor to generate corresponding feedback torque, providing the driver with real-time road feel feedback.

2. A prototype vehicle development test platform for drive-by-wire technology testing according to claim 1, characterized in that: The electrical device includes multiple groups of DCDCs, which are used to convert the high voltage output by the battery group into a low voltage to power the low-voltage system, and the high-voltage system is directly powered by the battery.

3. A prototype vehicle development test platform for drive-by-wire technology testing according to claim 2, characterized in that: The electrical components also include contactor switches, start switches, emergency stop switches, fuses, and distributors for ensuring the smooth and safe operation of the electrical system and the entire vehicle system.

4. A prototype vehicle development test platform for drive-by-wire technology testing according to claim 1 or 2, characterized in that: The platform also includes a wire-controlled suspension system, and the communication module is responsible for data transmission between the wire-controlled suspension system and the VCU and the host computer.

5. The prototype vehicle development test platform for drive-by-wire technology testing according to claim 4, characterized in that: In addition to enabling independent control testing of each drive-by-wire system, the platform can also develop and test coordinated control strategies for all drive-by-wire chassis systems and provide a control development interface for the drive-by-wire suspension. The drive-by-wire steering, brake-by-wire, drive-by-wire, and suspension-by-wire systems achieve information exchange and collaborative control through the vehicle control unit.

6. A prototype vehicle development test platform for drive-by-wire technology testing according to claim 5, characterized in that: The VCU collects vehicle status and driver intentions in real time, and after comprehensive analysis based on a given collaborative strategy, sends control instructions to each subsystem to optimize the vehicle's target performance.

7. The prototype vehicle development test platform for drive-by-wire technology testing according to claim 6, characterized in that: The platform can achieve multiple vehicle performance objectives and multi-system coordinated control. Through optimization algorithms, it can optimize the coordinated control design of various chassis subsystems, coordinate the coupling of various chassis subsystems, reduce conflicts between systems, and improve handling stability and braking efficiency.

8. The prototype vehicle development test platform for drive-by-wire technology testing according to claim 7, characterized in that: During emergency braking, the wire control brake system responds to the brake pedal signal, the wire control steering system adjusts the steering assist, the wire control drive system adjusts the power output, and the wire control suspension system adjusts the shock absorber damping to jointly maintain vehicle stability.

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