CN118665098A - Rear wheel lifting and follow-up steering control system of commercial vehicle - Google Patents

Abstract

The present invention discloses a rear wheel lifting and follow-up steering control system for commercial vehicles, including: a controller module: used to realize operator interaction, obtain real-time information from a sensor module, perform logic calculations, and send control instructions to an actuator module; a sensor module: used to use sensors to obtain real-time information of the vehicle and send real-time information to the controller module; an actuator module: used to obtain control instructions from the controller module, control the inflation and deflation of the airbag bridge air circuit, and realize the lifting and lowering movement of the rear wheel. The execution module includes: a two-position five-way solenoid valve and an electric power steering assembly; a basic module: used to support the control system to execute control operations. According to the above technical scheme, when performing rear wheel lifting and follow-up control, the lifting range can be scientific, the load-bearing capacity can be strong, the follow-up steering response speed can be fast, and the control accuracy can be high, thereby improving the maneuverability and control performance of commercial vehicles under complex road conditions and ensuring driving safety and stability.

Description

A commercial vehicle rear wheel lifting and follow-up steering control system

Technical Field

The invention relates to the field of automobile chassis control, and in particular to a rear wheel lifting and follow-up steering control system for commercial vehicles.

Background Art

With the development of automotive electronic technology, electronic control technology has provided new solutions for improving vehicle handling and stability. Most commercial vehicle rear wheel lifting and follow-up steering control systems use mechanical or hydraulic transmission methods for rear wheel lifting and follow-up steering. These methods have problems such as slow follow-up steering response speed, insufficient control accuracy, limited rear wheel lifting adjustment range, inability to adapt to different road conditions and load conditions, and hidden dangers to driving safety.

Therefore, a system with controllable rear wheel lifting and lifting range, strong load-bearing capacity, fast follow-up steering response speed and high control accuracy is needed to improve the maneuverability, handling performance and driving stability of multi-axle commercial vehicles under complex road conditions.

Summary of the invention

To achieve the above object, the present invention provides a commercial vehicle rear wheel lifting and follow-up steering control system, comprising:

Controller module: used to realize operator interaction, obtain real-time information from the sensor module, perform logical calculations, and send control instructions to the actuator module; the controller module includes: a controller, a control switch, and an indicator light; the control signals supported by the control switch include: rising, lowering, and automatic; the indicator light supports indicating the rear wheel status and fault status; the controller adopts the Infineon 32-bit microcontroller AURIX TC234LP.

Sensor module: used to obtain real-time information of the vehicle using sensors and send the real-time information to the controller module; the real-time information includes steering wheel angle information, main air reservoir pressure signal, airbag pressure signal, and steering push rod linear displacement;

Actuator module: used to obtain control instructions from the controller module, control the inflation and deflation of the airbag bridge air circuit, and realize the lifting and lowering movement of the rear wheel; execute the control request output to realize the steering movement of the rear wheel; the execution module includes: two-position five-way solenoid valve, electric power steering assembly;

Basic module: used to support the control system to perform control operations, including: wiring harness, power supply;

Among them, after the controller module obtains the real-time information from the sensor module, it calculates and generates real-time driving parameters, including: airbag bridge load and steering angle.

Further, the sensor module includes: a steering angle sensor, an air reservoir pressure sensor, an airbag pressure sensor 1, an airbag pressure sensor 2, and a linear displacement sensor;

The steering angle sensor uses CAN communication to transmit steering wheel angle information to the controller in real time; the CAN communication between the steering angle sensor and the electric power steering assembly is realized by the controller;

The controller is connected to the vehicle CAN to read the vehicle speed information; the controller also verifies whether the zero position of the steering angle sensor is reasonable based on the change of the linear displacement of the steering push rod.

The electric power steering assembly receives instructions from the controller to rotate, thereby driving the rear wheels to perform follow-up steering.

The two-position five-way solenoid valve is controlled by the switch quantity of the controller to change the inflation and deflation of the airbag bridge air circuit to realize the lifting and lowering movement of the rear wheel.

Further, the control instructions include: system self-check, rear wheel lowering, rear wheel raising, lowering prohibited, rear wheel steering, steering prohibited;

Logical calculation refers to: obtaining real-time information, judging control requirements, and sending control instructions to the specified module; real-time information is used to calculate the driving parameters required for control requirements, including: vehicle speed, control signal, vehicle mass, and steering angle; control requirements are completed by multiple components in coordination, and operations containing control instructions of multiple components include: system power-on, control rear wheel lifting, prohibition of rear wheel lowering, and system power-off; among which, control rear wheel lifting includes control rear wheel lifting and control rear wheel lowering;

When the control requirement is that the system is powered on, the controller sends a system self-test instruction to the control system to obtain the self-test result; if the self-test result is abnormal, a fault instruction is sent to the indicator light to stop the logical calculation; if the self-test result is normal, a logical calculation is performed to determine the control requirement, and the controller sends a control instruction to the actuator module according to the control requirement.

Specifically, the logic calculation includes the following steps:

When the vehicle speed is less than the specified threshold and the control signal is not automatic, the control demand is to control the rear wheels to rise or to control the rear wheels to fall according to the control signal analysis;

When the vehicle speed is less than the specified threshold and the control signal is automatic, the control requirement is to control the rear wheels to rise or to control the rear wheels to fall according to the vehicle mass analysis;

When the vehicle speed is greater than the specified threshold and the control signal is not automatic, based on the control signal analysis, the control requirement is to control the rear wheels to rise or prohibit the rear wheels from falling;

When the vehicle speed is greater than the specified threshold and the control signal is automatic, based on the vehicle mass analysis, the control requirement is to control the rear wheels to rise or prohibit the rear wheels from lowering.

Among them, when the control requirement is to control the rear wheel to lower, the control instructions issued by the controller include: rear wheel lowering, rear wheel steering, rear wheel status indicator lighting;

When the control requirement is to control the rear wheel to rise, the control instructions issued by the controller include: rear wheel rise, rear wheel steering, rear wheel status indicator off;

When the control requirement is to prohibit the rear wheels from lowering, the control instructions issued by the controller include: prohibiting lowering and prohibiting steering.

When the control demand is that the system is powered off, the control instructions issued by the controller include: rear wheel rising, rear wheel steering, and rear wheel status indicator off.

The control system proposed by the present invention has the following advantages and beneficial effects compared with the prior art:

(1) The rear wheels are lifted and lowered by means of electric control and pneumatics, and the vehicle mass of a multi-airbag bridge commercial vehicle can be calculated to achieve automatic lifting of the rear wheels. The structure is simple and the operation is convenient.

(2) The use of wire-controlled electric steering allows the rear wheels to support a larger steering angle and torque, with good steering followability and precise steering angle control. At the same time, the flexibility of the rear end of the vehicle is enhanced, improving the vehicle's maneuverability and stability;

(3) Supports reading vehicle status data on the vehicle CAN bus, reducing the number of sensors used and improving reliability.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the structure of a control system provided according to an embodiment of the present invention;

FIG2 is a distribution diagram of structural components of a control system provided according to an embodiment of the present invention;

3 is a control system logic calculation flow chart provided according to an embodiment of the present invention;

Figure markings: 1-on-board power supply, 2-controller, 3-steering angle sensor, 4-two-position five-way solenoid valve, 5-air reservoir pressure sensor, 6-airbag pressure sensor 1, 7-airbag pressure sensor 2, 8-linear displacement sensor, 9-electric power steering assembly, 10-control switch, 11-fault indicator light, 12-rear wheel status indicator light, 13-wiring harness.

DETAILED DESCRIPTION

The present invention provides a rear wheel lifting and follow-up steering control system for commercial vehicles. An independent control structure is added to the chassis of the commercial vehicle. While realizing the lifting and lowering control of the rear wheel by means of electric control and pneumatics, the rear wheel follow-up steering is controlled. In terms of structure, the system supports integration with the existing components of the vehicle, avoids adding new components as much as possible, and maximizes the application of existing components. The control process mainly includes: the controller controls the two-position five-way solenoid valve, changes the air path of the airbag bridge, realizes the lifting and lowering of the rear wheel, increases the rear wheel steering coordination after the rear wheel is lowered, and reduces the turning radius. At the same time, a manual lifting control mode and an automatic lifting control mode are provided to realize manual selection and automatic lifting control according to driving speed, vehicle mass and other elements, thereby improving the operability of the operator. During the entire lifting control process, the airbag bridge where the rear wheel is located can adapt to different road conditions, match the vehicle speed and load to adjust the height of the rear wheel in real time, so as to improve the maneuverability and control performance of multi-axle commercial vehicles under complex road conditions, ensure safety and driving stability.

During the rear wheel lifting and lowering control process, the rear wheel follow-up steering control is simultaneously realized, supporting large-angle and high-precision follow-up reverse steering of the rear wheel: the steering angle is determined by the controller after obtaining the accurate angle value of the steering angle sensor and calculating, and the electric power steering assembly drives the rear wheel to control the turning angle and amplitude, realizing rapid response and high-precision control of the rear wheel steering.

The specific implementation of the present invention is described in detail below with reference to the accompanying drawings.

The automotive components and layout for controlling the lifting and following steering of the rear wheels of commercial vehicles are shown in Figure 2, including the on-board power supply, controller, steering angle sensor, two-position five-way solenoid valve, air reservoir pressure sensor, airbag pressure sensor 1, airbag pressure sensor 2, linear displacement sensor, electric power steering assembly, control switch, fault indicator light, and rear wheel status indicator light.

The above components constitute the implementation structure of the control system for rear wheel lifting and follow-up steering provided by the present invention, and the implementation structure is shown in FIG1 , including: a controller module, a sensor module, an actuator module, and a basic module;

P100 basic module: used to support the basic power and transmission functions of the control system to perform control operations, including: wiring harness, power supply; the power supply can be powered by the original vehicle's battery, and in the embodiment of the present invention, the vehicle-mounted power supply is used to power the entire system.

P110 controller module: used to realize operator interaction, obtain real-time information from the sensor module, perform logical calculations, and send control instructions to the actuator module;

As shown in the figure, the controller module includes: a controller, a control switch, and an indicator light;

The controller uses the Infineon 32-bit microcontroller AURIXTC234LP with high-performance computing power and rich resources. It controls the actuator module by calculating and processing the system sensor signals and vehicle status information to achieve the lifting and following steering of the rear wheels.

The control switch can realize some functions of the interaction between the control system and the operator, that is, to judge the driver's use intention under certain conditions, and realize the lifting and steering of the rear wheels through simple operations; the control signals supported by the control switch include at least: lifting, lowering, and automatic lifting; in the embodiment of the present invention, a three-speed control switch is used, and the lifting, lowering, and automatic lifting of the rear wheels can be realized by selecting the gear position;

The indicator light can realize part of the functions of the control system and the operator's interaction, and prompt the operator with the control status; the status that can be indicated includes the rear wheel status and the fault status; all the statuses can be displayed by one indicator light, or different statuses can be displayed by multiple indicator lights. In the present invention, the rear wheel status indicator light and the fault indicator light are used to provide indication functions respectively;

The fault indicator light stays on or flashes when a system fault occurs, and is off when there is no fault.

The rear wheel status indicator light stays on when the rear wheels are lowered and goes off when they are raised.

P130 sensor module: used to obtain real-time vehicle information using sensors and send real-time information to the controller module; real-time information includes steering wheel angle information, main air reservoir pressure signal, airbag pressure signal, steering push rod linear displacement, vehicle mass, and vehicle speed;

The sensor module includes:

Steering angle sensor, which has high measurement accuracy and is used to collect the steering angle of the steering wheel;

The air tank pressure sensor is used to collect the air tank pressure. The air tank pressure can determine whether automatic lifting control can be performed. That is, the control system detects the air tank pressure during self-checking, and the rear wheel lifting operation can only be performed when it reaches a certain pressure range;

Airbag pressure sensor 1, used to collect the airbag pressure of the non-liftable rear airbag bridge and calculate the vehicle mass;

The airbag pressure sensor 2 is used to collect the airbag pressure of the retractable rear airbag bridge and calculate the load of the retractable airbag bridge;

The linear displacement sensor is used to collect the linear displacement of the steering push rod so that the controller can verify the rationality of the zero position of the steering angle sensor;

The steering angle sensor uses CAN communication to transmit steering wheel angle information to the controller in real time;

Among them, after the controller module obtains the real-time signals and information from the sensor module, it calculates and generates real-time driving parameters, including: airbag bridge load, steering angle, etc.

P120 actuator module: used to obtain control instructions from the controller module, control the inflation and deflation of the airbag bridge air circuit, and realize the lifting and lowering movement of the rear wheel; execute the control angle output to realize the steering movement of the rear wheel; the actuator module includes: two-position five-way solenoid valve and electric power steering assembly;

The two-position five-way solenoid valve is controlled by the switch quantity of the controller to change the inflation and deflation of the airbag bridge air path to achieve the lifting and lowering movement of the rear wheel. In the present invention, the air pressure supply of the existing airbag suspension system of the original vehicle can be used as the air pressure source to achieve the lifting and lowering of the rear wheel axle and parameter loading;

The electric power steering assembly receives instructions from the controller to rotate, pushing the rear wheels to steer; the direction and angle value of the rear wheel steer are determined by the steering angle value pushed by the controller, and the electric power steering assembly pushes the rear wheels to rotate in the opposite direction of the front wheels according to the angle value to achieve the rear wheel steer; when the angle value is zero, the electric power steering assembly pushes the rear wheels to gradually return to the center; the angle value is generated by the controller after converting the steering angle sensor angle received.

In specific implementation, the steering angle sensor collects the angle to calculate the front axle drop arm angle, the front axle drop arm angle is used to calculate the rear steering axle drop arm angle, and the steering angle of the electric power steering assembly is calculated by the rear steering axle drop arm angle; the controller sends the steering angle to the electric power steering assembly, and the electric power steering assembly drives the rear wheel steering. Since the rear wheel steering angle changes with the front wheel steering angle, the rear wheel steering angle range is wide, so that the rear wheel steering center coincides with the front wheel steering center, reducing the turning radius.

The wire-controlled electric power steering can achieve a large range of rear wheel follow-up reverse rotation, without the limitation of the small angle range of ordinary direct follow-up steering. After the rear wheel is lifted, the steering angle can also be decoupled and the rear wheel can be returned to the positive position.

Among them, the CAN communication between the steering angle sensor and the electric power steering assembly is realized through the controller.

In the present invention, the steering angle sensor collects the front wheel angle as the steering basis for the electric power steering assembly to drive the rear wheel, and the steering angle range is large, the control accuracy is high, and the response is rapid.

The collaborative process of each module of the control system can be simply summarized as follows: the sensor module sends the current driving data to the controller module, the controller module combines the operator's intention and real-time driving parameters, and obtains matching control requirements through logical calculation and analysis, and sends different control instructions corresponding to different control requirements to different components. The actuator module executes the control instructions to realize rear wheel lifting and follow-up steering.

Control instructions refer to the execution instructions or drive outputs sent by the controller to the components of each module of the control system, including:

System self-check: including controller self-check and controller detection of whether the sensor module and actuator module are normal and whether the lifting control indicators are met; for example, if the signal of the air tank pressure sensor is lost, the self-check fails; if the self-check fails, the fault light is on;

Lowering the rear wheel: driving the two-position five-way solenoid valve to lower the rear wheel;

Rear wheel rise: drive the two-position five-way solenoid valve to make the rear wheel rise;

Prohibit lowering: Drive the two-position five-way solenoid valve to prohibit the rear wheel from lowering;

Rear wheel steering: It is implemented through the electric power steering assembly, which pushes the rear wheels to turn in the specified direction and at the specified angle;

Prohibit steering: Executed through the electric power steering assembly, prohibiting rear wheel steering;

Rear wheel status indication and fault indication: executed by indicator lights. Multiple states can be displayed by one indicator light, or by the rear wheel status indicator light and fault indicator light respectively.

The logic calculation is performed by the controller, specifically: obtaining real-time information, judging control requirements, and sending control instructions to the specified module; the real-time information at this time is the driving parameters required for calculating the control requirements, including at least: vehicle speed, control signal, vehicle mass, and steering angle;

The control requirement is the analysis result of logical calculation, which needs to be completed by multiple components in coordination and includes the operation of control instructions executed by multiple drive components, specifically including: powering on the system, controlling the lifting of the rear wheels, prohibiting the rear wheels from lowering, and powering off the system; among which controlling the lifting of the rear wheels includes controlling the rear wheels to rise and controlling the rear wheels to lower.

After the system is powered on, if the power-on is successful, the controller sends a system self-test instruction to the control system, that is, to determine whether the controller module, sensor module, actuator module and basic module are normal, and obtain the self-test result; if the self-test result is abnormal, a fault instruction is sent to the indicator light and the logic calculation is stopped. If the self-test result is normal, logic calculation is performed to determine the control requirements, and the controller sends a control instruction to the actuator module according to the control requirements.

The specific logic calculation is shown in Figure 3, which includes the following steps:

When the vehicle speed is less than the specified threshold and the control signal is not automatic, according to the control signal analysis, the control demand is to control the rear wheels to rise or to control the rear wheels to fall; the specified threshold in the present invention is a preset value, for example, 20Km/h, when the control signal from the control switch is not automatic, that is, it is rising or falling, then the control demand corresponds to controlling the rear wheels to rise or to control the rear wheels to fall;

When the vehicle speed is less than the specified threshold and the control signal is automatic, the control requirement is to control the rear wheels to rise or fall according to the vehicle mass analysis; when the automatic control in the present invention is implemented, the controller adjusts the rise and fall of the rear wheels according to the vehicle mass, which can improve the driving stability. If the vehicle mass is greater than the vehicle threshold, the control requirement is to control the rear wheels to fall; otherwise, the control requirement is to control the rear wheels to rise; the vehicle threshold can also be adjusted according to the vehicle model;

When the vehicle speed is greater than the specified threshold and the control signal is not automatic, the control demand is to control the rear wheels to rise or prohibit the rear wheels from falling according to the control signal analysis; during driving, when the vehicle speed reaches a certain level, if the rear wheels are suddenly lowered, it will increase the driving risk. Therefore, when the control signal is lowering, the control system will not directly respond to the operator's intention, but define the control demand as prohibiting the rear wheels from falling; when the control signal is rising, the control demand is to control the rear wheels to rise;

When the vehicle speed is greater than the specified threshold and the control signal is automatic, according to the vehicle mass analysis, the control requirement is to control the rear wheels to rise or to control the rear wheels to rise according to the control signal. Specifically, if the vehicle mass is greater than the vehicle threshold, the control requirement is to prohibit the rear wheels from lowering; otherwise, the control requirement is to control the rear wheels to rise.

When the control requirement is to control the rear wheel to be lowered, the control instructions issued by the controller include: rear wheel lowering, rear wheel steering, rear wheel status indicator lighting, that is, driving the two-position five-way solenoid valve to realize the rear wheel lowering, and at the same time calculating the rear wheel steering angle according to the front wheel angle transmitted by the steering angle sensor, and sending the rear wheel steering angle to the electric power steering assembly, and the electric power steering assembly drives the rear wheel to rotate in the opposite direction with the front wheel, and at the same time, the controller drives the indicator light to indicate the rear wheel status light;

When the control requirement is to control the rear wheel to rise, the control instructions issued by the controller include: rear wheel rise, rear wheel steering, rear wheel status indicator off, that is, the controller stops driving the two-position five-way solenoid valve, and the rear wheel rises; the controller sends a zero angle to the electric power steering assembly, the electric power steering assembly pushes the rear wheel to gradually return to the center, and the controller stops driving the rear wheel status indicator light, indicating that the rear wheel status is off;

When the control requirement is to prohibit the rear wheels from lowering, the control instructions issued by the controller include: prohibiting lowering and prohibiting steering, that is, the controller stops driving the two-position five-way solenoid valve, and the controller sends a prohibition of steering to the electric power steering assembly, and the rear wheels are prohibited from steering.

It should be noted that when the control requirement is to control the rear wheels to rise or fall, the controller determines the effective stroke of rising and falling according to the load of the lifting airbag bridge to ensure the stability of the airbag bridge.

When the control requirement is that the system is powered off, the control instructions issued by the controller include: rear wheel lifting, rear wheel steering, and rear wheel status indicator off, that is, the controller stops driving the two-position five-way solenoid valve, the rear wheel lifts, the controller sends a zero angle to the electric power steering assembly, the rear wheel returns to the straight position, the controller stops driving the indicator light, and the rear wheel status indicator turns off.

In the control system provided by the present invention, the air pressure supply of the existing air bag suspension system can be used in structure as the air pressure source for lifting and bearing the rear wheel axle; the height valve of the existing suspension system can be used to adjust the height of the vehicle chassis; the battery of the original vehicle can be used to power the control system, etc., thereby reducing the increase of components in the structure and making the execution structure simple; at the same time, since the rear wheel axle adopts the air bag suspension system, a soft connection with the frame is achieved through compressed air, which can effectively filter most of the vibrations, and the height of the rear wheel can be adjusted in real time with the height valve to adapt to different road conditions; in terms of control implementation, the lifting and steering of the rear wheel is achieved through simple operations based on the driver's intention, and safety measures are formulated to avoid operational risks caused by inappropriate intentions; in terms of control implementation, an effective rotation angle is obtained through the electric power steering assembly to promote the direction and angle of the rear wheel steering, which can further control the steering accuracy and improve the response speed.

The above disclosures are only several specific embodiments of the present invention; however, the present invention is not limited thereto, and any changes that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims (10)

1. A rear wheel lift and follow-up steering control system for a commercial vehicle, comprising:

And a controller module: the system is used for realizing the interaction of operators, acquiring real-time information from the sensor module, executing logic calculation and sending a control instruction to the executor module; the controller module includes: the controller (2), the control switch (10) and the indicator lamp; the control signals supported by the control switch comprise: ascending, descending and automatic; the indicator lamp supports the indication of the rear wheel state and the fault state;

A sensor module: for acquiring real-time information of the vehicle using the sensor, transmitting the real-time information to the controller module; the real-time information comprises steering wheel angle information, a main air reservoir pressure signal, an air bag pressure signal and steering push rod linear displacement;

An actuator module: the control instruction is used for executing the control instruction from the controller module, controlling the air channel of the air bag bridge to be inflated and deflated, and realizing the lifting movement of the rear wheel; executing control angle output to realize steering movement of the rear wheels; the execution module comprises: a two-position five-way electromagnetic valve (4) and an electric power steering assembly (9);

And (3) a basic module: for supporting the control system to perform control operations, comprising: a wire harness (13) and a power supply (1);

After the controller module obtains the real-time information from the sensor module, real-time driving parameters are calculated and generated, and the method comprises the following steps: airbag bridge load, steering angle.

2. The rear wheel lift and follow-up steering control system of claim 1, wherein the sensor module comprises: a steering angle sensor (3), an air reservoir pressure sensor (5), an air bag pressure sensor (1, 6), an air bag pressure sensor (2, 7) and a linear displacement sensor (8);

the steering angle sensor (3) transmits steering wheel angle information to the controller (2) in real time in a CAN communication mode;

The controller (2) realizes CAN communication between the steering angle sensor (3) and the electric power steering assembly (9), and is connected with a whole vehicle CAN to read vehicle speed information;

The controller (2) checks whether the zero position of the steering angle sensor (3) is reasonable according to the change of the linear displacement of the steering push rod provided by the linear displacement sensor (8).

3. The commercial vehicle rear wheel lifting and follow-up steering control system according to claim 1, wherein the electric power steering assembly (9) receives an instruction from the controller (2) to rotate so as to push the rear wheel to follow-up steering; the rear wheel follow-up steering comprises reverse rotation and return of the front wheel.

4. The lifting and following steering control system for the rear wheel of the commercial vehicle according to claim 1, wherein the two-position five-way electromagnetic valve (4) is controlled by the switching value of the controller (2) to change the inflation and deflation of the air bag bridge air passage so as to realize the lifting movement of the rear wheel.

5. The rear wheel lifting and following steering control system of a commercial vehicle according to claim 1, wherein the controller (2) is an Infineon 32-bit single-chip microcomputer AURIX TC LP.

6. The commercial vehicle rear wheel lift and follow-up steering control system of claim 1, wherein the control command comprises: the system self-checking, the rear wheel descending, the rear wheel ascending, the falling prohibition, the rear wheel steering and the steering prohibition.

7. The rear wheel lift and follow-up steering control system of claim 6, wherein the logic calculation means: acquiring real-time information, judging control requirements, and sending control instructions to a designated module; the real-time information is driving parameters needed by calculation control demands, and comprises the following steps: vehicle speed, control signals, whole vehicle quality and steering angle; the control requirement is an operation of a control instruction which is cooperatively completed by a plurality of components and comprises a plurality of driving components, and the control requirement comprises the following steps: powering up the system, controlling the lifting of the rear wheel, prohibiting the falling of the rear wheel, and powering down the system; wherein controlling the lifting of the rear wheel comprises controlling the lifting of the rear wheel and controlling the lowering of the rear wheel;

When the control requirement is that the system is electrified, the controller (2) sends a system self-checking instruction to the control system to acquire a self-checking result; if the self-checking result is abnormal, a fault instruction is sent to the indicator lamp, logic calculation is stopped, if the self-checking result is normal, logic calculation is performed, a control requirement is judged, and the controller sends a control instruction to the executor module.

8. The rear wheel lift and follow-up steering control system of claim 7, wherein the logic calculation comprises the steps of:

When the vehicle speed is smaller than the specified threshold value and the control signal is not automatic, according to the control signal analysis, the control requirement is that the rear wheels are controlled to ascend or the rear wheels are controlled to descend;

When the vehicle speed is smaller than a specified threshold value and the control signal is automatic, controlling the rear wheels to ascend or descend according to the quality analysis of the whole vehicle;

When the vehicle speed is greater than a specified threshold value and the control signal is not automatic, analyzing according to the control signal, wherein the control requirement is to control the rear wheels to ascend or inhibit the rear wheels from descending;

When the vehicle speed is greater than a specified threshold value and the control signal is automatic, the control requirement is to control the rear wheels to ascend or inhibit the rear wheels from descending according to the whole vehicle quality analysis.

9. The rear wheel lift and follower steering control system of claim 8, wherein,

When the control requirement is that the rear wheel is controlled to descend, a control instruction sent by the controller (2) comprises: the rear wheel descends, the rear wheel turns to, and the rear wheel is indicated to be bright;

When the control requirement is that the rear wheel is controlled to ascend, the control instruction sent by the controller (2) comprises: the rear wheel rises, the rear wheel turns to and indicates to go out;

when the control requirement is that the rear wheel is forbidden to descend, the control instruction sent by the controller (2) comprises the following steps: descent and steering are prohibited.

10. The rear wheel lifting and follow-up steering control system for a commercial vehicle according to claim 9, wherein the control command issued by the controller (2) when the system is powered down comprises: the rear wheel rises and turns.