A pneumatic ABS brake pressure calculation system and method

Abstract

The present invention discloses a pneumatic ABS brake pressure calculation system and method, which relates to the technical field of wire-controlled chassis. The system includes: a slip rate calculation module, which is used to calculate the slip rate of the wheel; a wheel deceleration calculation module, which is used to calculate the deceleration of the wheel and filter it; a state monitoring module, which is used to determine the state of the wheel according to the slip rate, wheel deceleration and vehicle speed; a basic target braking force calculation module, which is used to calculate the target braking force in the initial state; an output target braking force calculation module, which is used to calculate and process the target braking force according to the state of the wheel; a target braking force filtering module, which is used to filter the target braking force according to the increase and decrease pressure state of the wheel. According to the technical solution of the present application, the stable braking function of the pneumatic ABS brake system of commercial vehicles under different road conditions can be realized, which has a high application value.

Description

Technical Field

[0001] The present invention relates to the technical field of wire-controlled chassis, and in particular to a pneumatic ABS brake pressure calculation system and method. Background Art

[0002] As a production tool, commercial vehicles are driving economic development. Due to their complex usage scenarios, commercial vehicles frequently have safety accidents during use. How to improve the safety of commercial vehicles has become a major problem in the production process of commercial vehicles. As one of the active safety devices of the vehicle, the vehicle anti-lock braking system adjusts the degree of wheel locking by controlling the braking torque according to wheel speed feedback. It can make full use of the adhesion of the road and ensure the stability of the vehicle in emergency braking, which is crucial to improving the safety of the vehicle. Existing commercial vehicles usually use compressed air as a power source to perform braking control on the vehicle. The ABS braking system equipped with it estimates the friction coefficient of the current road surface based on the slip rate and the recovery of the wheel speed through the target slip rate control method, thereby calculating the target braking force of a single wheel to brake the vehicle. However, due to the unstable actual pressure response of the air pressure, the estimation of the friction coefficient is prone to deviation, and the ABS braking system frequently triggers decompression or pressure increase, resulting in unstable braking strength of the braking system. Therefore, the development of a simple and efficient method to improve the stability of the commercial vehicle air pressure ABS braking system under different road conditions is imminent.

[0003] Most of the existing methods that can improve the stability of commercial vehicle pneumatic ABS brake systems under different road conditions have defects in some aspects. For example, the method based on the electronic control brake system controls the pressure of the brake chamber through the electronic control unit and the axle control module, which can accurately control the braking force, but this method has the problem of high cost and excessive reliance on the electronic system. Therefore, based on this problem, the present application proposes a pneumatic ABS brake pressure calculation system and method. Summary of the invention

[0004] Technical Purpose

[0005] In order to solve the above problems, the purpose of the present invention is to provide a pneumatic ABS brake pressure calculation system and method, which solves the problem that the stability of the pneumatic ABS brake system of commercial vehicles is easily affected under different road conditions. The system and method have a wide range of application scenarios, ensure the braking strength of the braking system under different road conditions, reduce the response time of the target braking force and the adjustment time of the system, and eliminate the phenomenon of abrupt braking.

[0006] Technical Solution

[0007] In order to achieve the above-mentioned purpose, the present invention provides a pneumatic ABS brake pressure calculation system and method, which distinguish the state of the wheel according to the slip rate and deceleration of the wheel, determine the control mode of the coaxial wheel according to the state of the wheel and the actual wheel cylinder pressure difference, and adjust the brake pressure in time according to the different states of the wheels. When the wheel has a tendency to slip, the brake pressure is adjusted according to the actual wheel cylinder pressure of the wheel. When the wheel has entered a slipping state, the brake pressure is adjusted according to the comparison result between the actual slip rate and the target slip rate, thereby realizing the stable braking function of the pneumatic ABS brake system of commercial vehicles under different road conditions.

[0008] In a first aspect, the present invention provides a pneumatic ABS brake pressure calculation system, comprising:

[0009] A slip rate calculation module, used for calculating the slip rate of the wheel;

[0010] Wheel deceleration calculation module, used to calculate the deceleration of the wheel and perform filtering;

[0011] A state monitoring module is used to determine the state of the wheel based on the slip rate, wheel deceleration and vehicle speed;

[0012] A basic target braking force calculation module, used to calculate the target braking force in the initial state;

[0013] Output target braking force calculation module, used to calculate and process the target braking force according to the state of the wheel;

[0014] The target braking force filtering module is used to filter the target braking force according to the pressure increase or decrease state of the wheel.

[0015] Furthermore, the state of the wheel is determined based on the slip rate of the wheel and the deceleration of the wheel.

[0016] Furthermore, the wheel slip rate calculation logic is to divide the difference between the vehicle speed and the wheel speed by the vehicle speed and then multiply it by 100%, where zero percent indicates that the wheel has no slip and 100% indicates that the wheel is completely locked; the wheel deceleration calculation logic is to differentiate the wheel speed and filter the differential value through a Kalman filter algorithm, and the filtering result is the final wheel deceleration value.

[0017] Furthermore, the state of the wheel includes a non-slip state, a slip tendency state and a slip state; the state of the wheel is determined based on the slip rate and the wheel deceleration.

[0018] Furthermore, when the slip rate is 0 and the wheel deceleration is greater than a certain threshold, the wheel is determined to be in a non-slip state; when the slip rate is greater than 0 and less than a certain threshold, and the wheel deceleration is greater than a certain threshold, the wheel is determined to be in a slipping tendency state; when the slip rate is greater than a certain threshold and the wheel deceleration is less than a certain threshold, the wheel is determined to be in a slipping state.

[0019] Furthermore, the target braking force in the initial state, i.e., the braking force generated when the ABS braking system is just triggered, is calculated by the vehicle mass multiplied by the target speed bump multiplied by the tire rolling radius divided by the wheel cylinder braking coefficient.

[0020] Furthermore, the pressure increase and decompression state of the wheel includes a pressure increase state, a pressure reduction state and a pressure maintaining state; the filtering algorithm is a variable step-size slope filter, and the filtering coefficient depends on the vehicle speed and the type of pressure increase and decompression.

[0021] Furthermore, when the two wheels on the same axis are in a state of slipping tendency, the control mode of the axis is determined according to the actual wheel cylinder pressure difference of the two wheels at this time; if the actual wheel cylinder pressure difference is small, the wheel enters the independent control mode, and each wheel calculates its target brake pressure separately; if the actual wheel cylinder pressure difference is large, the wheel enters the low-selection control mode, at which time the target brake pressure of the two wheels is the same and is calculated according to the target brake pressure of the wheel on the low-adhesion road side. It improves the stability of the vehicle during emergency braking, reduces the risk of vehicle loss of control due to wheel locking, improves the driving performance of the vehicle on slippery or uneven roads, enhances the stability of the vehicle in curve driving or obstacle avoidance operations, and improves driving comfort.

[0022] Furthermore, when the wheel is in a non-slip state, its target braking force is calculated according to the target deceleration of the whole vehicle corresponding to the brake pedal and the whole vehicle parameters according to the high adhesion road surface; when the wheel enters a slipping tendency state, its target braking force is calculated according to the actual wheel cylinder pressure at the moment the wheel enters the slipping tendency state; when the wheel is in a slipping tendency state, if its actual slip rate is less than the target slip rate, the feedforward compensation braking pressure and feedback pressure are increased on the basis of the current actual braking force and delayed; if its actual slip rate is greater than the target slip rate, the feedforward compensation braking pressure and feedback pressure are reduced on the basis of the current actual braking force and delayed. It adjusts the braking pressure by combining feedforward compensation and feedback control, which can reduce the braking distance and improve the braking efficiency of the vehicle; when adjusting the braking pressure, a delay mechanism is introduced to reduce the impact caused by the braking process by smoothly adjusting the braking pressure, thereby improving ride comfort.

[0023] Furthermore, the system also includes an intelligent braking module, which is used to calculate the required braking pressure through the electronic control unit according to the sensor signal, and adjust the pressure of the brake chamber by controlling the brake pressure regulator. It can intelligently select the combination of mechanical braking and electric braking according to the vehicle state and driving conditions, improve the reliability and safety of the system, and provide necessary technical support for autonomous driving.

[0024] Furthermore, the system also includes a dynamic matrix control module, which is used to realize dynamic characteristic analysis of the target braking force, and to perform optimization calculations within the control cycle through a rolling optimization strategy to determine the control strategy for a period of time in the future. It adjusts the braking strategy in real time through rolling optimization and feedback correction mechanisms to adapt to changes in vehicle status and road conditions, reducing the braking distance, improving the active safety of the vehicle, and improving the stability and reliability of the system when facing nonlinear characteristics.

[0025] In a second aspect, the present invention further provides a method for calculating pneumatic ABS brake pressure, the method being based on the system described in the first aspect, comprising:

[0026] Determine the state of the wheel based on the wheel slip rate and deceleration;

[0027] Calculate and process the target braking force according to the state of the wheel;

[0028] Filtering the target braking force according to the increase or decrease pressure status of the wheel;

[0029] Finally, the air pressure ABS brake pressure is obtained.

[0030] In a third aspect, the present invention also provides a computer device, comprising a processor and a memory, wherein the processor is connected to the memory, the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory so that the computer device executes the aforementioned pneumatic ABS brake pressure calculation method.

[0031] In a fourth aspect, the present invention further provides a computer-readable storage medium, wherein a computer program is stored in the computer-readable storage medium, and when the computer program is executed by a processor, the aforementioned pneumatic ABS brake pressure calculation method is implemented.

[0032] The present invention distinguishes the state of the wheel according to the slip rate and deceleration of the wheel, determines the control mode of the coaxial wheel according to the state of the wheel and the actual wheel cylinder pressure difference; adjusts the brake pressure in time according to the different states of the wheel, adjusts the brake pressure according to the actual wheel cylinder pressure of the wheel when the wheel has a tendency to slip, and adjusts the brake pressure according to the comparison result between the actual slip rate and the target slip rate when the wheel has entered the slip state; the intelligent brake module can calculate the required brake pressure according to the sensor signal and the electronic control unit, and adjust the pressure of the brake air chamber by controlling the brake pressure regulator; the dynamic matrix control module can realize the dynamic characteristic analysis of the target braking force, and optimize the calculation within the control cycle through the rolling optimization strategy to determine the control strategy for a period of time in the future. The system and method solve the problem that the stability of the commercial vehicle air pressure ABS brake system is easily affected under different road conditions. The system and method have a wide range of application scenarios, ensure the braking strength of the brake system under different road conditions, reduce the response time of the target braking force and the adjustment time of the system, and eliminate the phenomenon of braking abruptness.

[0033] Beneficial Effects

[0034] By implementing the pneumatic ABS brake pressure calculation system and method provided by the present invention, the following technical effects are achieved:

[0035] (1) The wheel status is distinguished according to the wheel slip rate and deceleration, and the control mode of the coaxial wheel is determined according to the wheel status and the actual wheel cylinder pressure difference; it improves the stability of the vehicle during emergency braking and reduces the risk of vehicle loss of control due to wheel locking; it improves the vehicle's driving performance on slippery or uneven roads; it enhances the vehicle's stability in curve driving or obstacle avoidance operations and improves driving comfort.

[0036] (2) The brake pressure is adjusted in time according to the different states of the wheels. When the wheels tend to slip, the brake pressure is adjusted according to the actual wheel cylinder pressure of the wheels. When the wheels have entered a slipping state, the brake pressure is adjusted according to the comparison result between the actual slip rate and the target slip rate. The brake pressure is adjusted by combining feedforward compensation and feedback control to reduce the braking distance and improve the braking efficiency of the vehicle. A delay mechanism is introduced when adjusting the brake pressure to reduce the impact caused by the braking process by smoothly adjusting the brake pressure, thereby improving ride comfort.

[0037] (3) The intelligent braking module can calculate the required braking pressure based on sensor signals through the electronic control unit and adjust the pressure of the brake chamber by controlling the brake pressure regulator. It can intelligently select the combination of mechanical braking and electric braking according to the vehicle status and driving conditions, thereby improving the reliability and safety of the system and providing the necessary technical support for autonomous driving.

[0038] (4) The dynamic matrix control module can realize the dynamic characteristics analysis of the target braking force, and perform optimization calculations within the control cycle through the rolling optimization strategy to determine the control strategy for a period of time in the future; it adjusts the braking strategy in real time through the rolling optimization and feedback correction mechanism to adapt to changes in vehicle status and road conditions, thereby reducing the braking distance, improving the active safety of the vehicle, and improving the stability and reliability of the system when facing nonlinear characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to make the above-mentioned air pressure ABS brake pressure calculation system and method of the present invention more obvious and easy to understand, the drawings required for use in the specific implementation of the present invention 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 paying creative labor.

[0040] Figure 1 A schematic diagram showing a pneumatic ABS brake pressure calculation system;

[0041] Figure 2 A schematic diagram showing a method for calculating the air pressure ABS brake pressure;

[0042] Figure 3 A schematic diagram showing a coordinated flow of controlling wheel brake pressure;

[0043] Figure 4 Schematic diagram showing the calculation process of brake pressure for a single wheel. DETAILED DESCRIPTION

[0044] Embodiment 1:

[0045] Provided is a pneumatic ABS brake pressure calculation system and method, the pressure calculation system is as follows Figure 1 As shown, the pressure calculation method is as follows Figure 2 As shown, the system includes: a slip rate calculation module, a wheel deceleration calculation module, a state monitoring module, a basic target braking force calculation module, an output target braking force calculation module and a target braking force filtering module, as follows.

[0046] The slip rate calculation module is used to calculate the slip rate of the wheel; the slip rate calculation logic of the wheel is the difference between the vehicle speed and the wheel speed divided by the vehicle speed and then multiplied by 100%, where 0% means that the wheel has no slip and 100% means that the wheel is completely locked.

[0047] The wheel deceleration calculation module is used to calculate the deceleration of the wheel and filter it; the wheel deceleration calculation logic is to differentiate the wheel speed and filter the differential value through the Kalman filter algorithm, and the filtering result is the final wheel deceleration value.

[0048] A state monitoring module is used to determine the state of the wheel according to the slip rate, wheel deceleration and vehicle speed; the state of the wheel includes a non-slip state, a slip tendency state and a slip state, and the state of the wheel is determined according to the slip rate of the wheel and the deceleration of the wheel: when the slip rate is 0 and the wheel deceleration is greater than a certain threshold, the wheel is determined to be in a non-slip state; when the slip rate is greater than 0 and less than a certain threshold, and the wheel deceleration is greater than a certain threshold, the wheel is determined to be in a slip tendency state; when the slip rate is greater than a certain threshold and the wheel deceleration is less than a certain threshold, the wheel is determined to be in a slip state.

[0049] The basic target braking force calculation module is used to calculate the target braking force in the initial state; the target braking force in the initial state is the braking force generated when the ABS braking system is just triggered, and its calculation logic is the vehicle mass multiplied by the target speed bump multiplied by the tire rolling radius divided by the wheel cylinder braking coefficient.

[0050] The output target braking force calculation module is used to calculate and process the target braking force according to the state of the wheel.

[0051] The target braking force filtering module is used to filter the target braking force according to the pressure increase or decrease state of the wheel; the pressure increase or decrease state of the wheel includes the pressure increase state, the pressure decrease state and the pressure maintenance state; the filtering algorithm is a variable step slope filter, and the filtering coefficient depends on the vehicle speed and the type of pressure increase or decrease.

[0052] Control wheel brake pressure coordination process such as Figure 3 As shown, the wheel speed and vehicle speed signals are passed through the slip rate calculation and wheel deceleration calculation modules to calculate the slip rate and wheel deceleration of each wheel; taking the front axle as an example, the slip rate and wheel deceleration signals of the FR (front engine rear wheel drive) and FF (front engine front wheel drive) wheels are respectively input into the FR and FF state monitoring modules, which judge the current state of the wheel according to the slip rate and wheel deceleration. When two wheels are in a state of slipping tendency, the actual wheel cylinder pressures of the two wheels in the state of slipping tendency are recorded respectively and compared, and the actual wheel cylinder pressure difference of the two coaxial wheels in the state of slipping tendency is used for determination. Segment and determine the control mode of the axle; if the actual wheel cylinder pressure difference when the two wheels are in a state of slipping tendency is small, it means that the road adhesion of the left and right wheels is not much different, the left and right wheels enter independent control mode, and the target braking pressure is calculated separately for each wheel; if the actual wheel cylinder pressure difference when the two wheels are in a state of slipping tendency is large, it means that the road adhesion of the left and right wheels is very different, the left and right wheels enter low-select control mode, at this time the target braking pressure of the two wheels is the same and is calculated according to the target braking pressure of the wheel on the low-adhesion road side; the working principle of the rear axle is the same as that of the front axle.

[0053] The calculation process of brake pressure of a single wheel is as follows: Figure 4 As shown in the figure, the wheel speed and vehicle speed signals are passed through the slip rate calculation and wheel deceleration calculation modules to calculate the slip rate and wheel deceleration of each wheel; taking a single wheel from a uniform high-adhesion road surface to a uniform low-adhesion road surface and then to a uniform high-adhesion road surface as an example, when the driver steps on the brake, the system monitors the state of the wheel in real time based on the calculated wheel slip rate and wheel deceleration, and calculates the required target braking force based on the different states of the wheel; when the wheel is in a non-slip state, its target braking force is calculated based on the vehicle target deceleration corresponding to the brake pedal and the vehicle parameters according to the high-adhesion road surface; when the wheel shows a tendency to lock on a uniform low-adhesion road surface, the target braking force of the wheel at this time is calculated based on the wheel entering a slipping state. The instantaneous actual wheel cylinder pressure in the potential state is calculated. The main control target of the system in the state with a slip tendency is the target slip rate of the wheel. If the actual slip rate is less than the target slip rate, the feedforward compensation braking pressure and feedback pressure are increased on the basis of the current actual braking force and a delay is performed. If the actual slip rate is greater than the target slip rate, the feedforward compensation braking pressure and feedback pressure are reduced on the basis of the current actual braking force and a delay is performed to ensure that the actual slip rate of the wheel is within the target range. When the vehicle goes from a uniform low-adhesion road surface to a uniform high-adhesion road surface, the wheel state changes from a slip tendency state to a non-slip state. At this time, its target braking force is recalculated according to the calculated value of the non-slip state.

[0054] The system also includes an intelligent braking module, which is used to calculate the required braking pressure through the electronic control unit according to the sensor signal, and adjust the pressure of the brake air chamber by controlling the brake pressure regulator, specifically including: solving the compatibility problem between the intelligent braking system and the pneumatic braking system through the pneumatic braking structure; collecting vehicle status information in real time through sensors, and transmitting the sensor data to the electronic control unit through the CAN bus; calculating the required braking pressure in real time through the electronic control unit, and establishing a calculation model for the braking pressure according to the pneumatic characteristics and pressure response; formulating corresponding control strategies according to the driver's braking intention and external conditions and through the calculation model, and finally transmitting the calculated braking pressure to each brake air chamber through the electronically controlled brake master valve; the application of the intelligent braking solution can reduce the response time of the pneumatic ABS braking system from about 600 milliseconds to less than 150 milliseconds.

[0055] Embodiment 2:

[0056] On the basis of the above-mentioned embodiment, the system adds a dynamic matrix control module to realize the dynamic characteristic analysis of the target braking force, and performs optimization calculation within the control cycle through the rolling optimization strategy to determine the control strategy for a period of time in the future;

[0057] The dynamic characteristics of the air ABS brake pressure are described by the relationship between the brake pressure and the braking time, specifically:

[0058]

[0059] in, Indicates at time Braking pressure at It represents the proportionality factor, which is related to the pressure increase rate of the brake system; Represents the attenuation coefficient, which is related to the pressure decay rate of the brake system; Indicates steady-state pressure, that is, the value when the brake pressure reaches stability.

[0060] The prediction model is constructed through the system's step response sequence to predict the future output of the system under different control inputs:

[0061]

[0062] in, Indicates at time The system output prediction, i.e. the predicted value of the brake pressure; Represents the initial forecast value, which is based on the current state and historical data; represents the dynamic matrix, which is composed of the step response sequence of the system; Represents the control increment sequence, that is, at time Changes in the amount of control that needs to be applied; represents the coefficient matrix related to brake pressure; Indicates the change in brake pressure, that is, the increase in pressure during the braking process.

[0063] In each control cycle, the optimization algorithm is used to calculate the optimal control increment sequence according to the current system state and the prediction model. The objective function is defined in quadratic form, and the optimal control increment is obtained by quadratic calculation:

[0064]

[0065] in, Represents the optimal control increment, which is the optimal control increment at the current moment obtained by the optimization algorithm and is used to achieve the optimal adjustment of the system state; Represents the output weight matrix, which is used to adjust the weight of the prediction error in the optimization objective function; represents the control weight matrix, which is used to adjust the weight of the control increment in the optimization objective function; represents the brake pressure control weight matrix, which is used to adjust the priority of brake pressure control; represents the reference trajectory, i.e., the desired system output; Represents the predicted system output.

[0066] After the control increment, the prediction model is corrected by collecting the real-time output data of the system and comparing it with the prediction model. The prediction value of the corrected model is:

[0067]

[0068] in, represents the corrected model prediction value, taking into account the error correction; Indicates at time The model prediction value of , without considering error correction; Represents the error weighted sequence, which is used to adjust the impact of errors in the prediction model; Represents the nonlinear correction term, which is used to deal with nonlinear errors; Represents the error between the predicted output and the actual output.

[0069] The calculated control increment is applied to the system to achieve precise control of the air ABS brake pressure.

[0070] For example, suppose there is a linear system whose dynamic matrix for , control input influence matrix for ; Set the weight matrix for , control weight matrix for ; Expected output ; Current output ; Current control increment ;

[0071] Prediction model calculation:

[0072]

[0073] Rolling optimization calculation:

[0074]

[0075]

[0076]

[0077] Assumptions is the error vector, To predict the output, correction is performed.

[0078] The effect of the dynamic matrix control scheme is shown in Table 1:

[0079] Table 1. Summary of the effects of dynamic matrix control scheme

[0080]

[0081] As shown in Table 1, the brake pressure control accuracy of the model after optimization by the dynamic matrix control scheme is significantly improved, and the error is greatly reduced; this indicates that the dynamic matrix control scheme can significantly improve the accuracy of the air pressure ABS brake pressure calculation method.

[0082] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable non-transient storage media containing computer-usable program code.

[0083] The present invention can provide computer program instructions to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce means for implementing the system.

[0084] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions of the system.

[0085] These computer program instructions may also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable device provide steps for implementing the functions of the system.

Claims

1. A pneumatic ABS brake pressure calculation system, characterized in that: include: A slip rate calculation module, used for calculating the slip rate of the wheel; Wheel deceleration calculation module, used to calculate the deceleration of the wheel and perform filtering; A state monitoring module, used to determine the state of the wheel according to the slip rate, wheel deceleration and vehicle speed, wherein the state of the wheel includes a non-slip state, a slip tendency state and a slip state; A basic target braking force calculation module, used to calculate the target braking force in the initial state; The output target braking force calculation module is used to calculate and process the target braking force according to the state of the wheel, specifically including: when the wheel is in a non-slip state, the target braking force is calculated according to the target deceleration of the whole vehicle corresponding to the brake pedal and the whole vehicle parameters according to the high adhesion road surface; when the wheel enters a state with a slip tendency, the target braking force is calculated according to the actual wheel cylinder pressure at the moment the wheel enters the state with a slip tendency; when the wheel is in a state with a slip tendency, if the actual slip rate is less than the target slip rate, the feedforward compensation braking pressure and feedback pressure are increased on the basis of the current actual braking force and a delay is performed; if the actual slip rate is greater than the target slip rate, the feedforward compensation braking pressure and feedback pressure are reduced on the basis of the current actual braking force and a delay is performed; The target braking force filtering module is used to filter the target braking force according to the pressure increase or decrease state of the wheel.

2. The pneumatic ABS brake pressure calculation system according to claim 1, characterized in that: The state of the wheel is determined based on the slip rate of the wheel and the deceleration of the wheel.

3. The pneumatic ABS brake pressure calculation system according to claim 1, characterized in that: When two coaxial wheels are in a state of slipping tendency, the control mode of the axle is determined according to the actual wheel cylinder pressure difference between the two wheels at this time; if the actual wheel cylinder pressure difference is small, the wheel enters the independent control mode, and each wheel calculates its target braking pressure separately; if the actual wheel cylinder pressure difference is large, the wheel enters the low-select control mode, and the target braking pressures of the two wheels are the same and are calculated according to the target braking pressure of the wheel on the low-adhesion road surface side.

4. The pneumatic ABS brake pressure calculation system according to any one of claims 1 to 3, characterized in that: The system further comprises an intelligent brake module, which is used for calculating the required brake pressure according to the sensor signal through the electronic control unit and adjusting the pressure of the brake air chamber by controlling the brake pressure regulator.

5. The pneumatic ABS brake pressure calculation system according to any one of claims 1 to 3, characterized in that: The system also includes a dynamic matrix control module for realizing dynamic characteristic analysis of target braking force and performing optimization calculation within a control cycle through a rolling optimization strategy to determine a control strategy for a period of time in the future.

6. A method for calculating pneumatic ABS brake pressure, characterized in that: The implementation of the method is based on the system described in any one of claims 1 to 5: The method comprises: Determine the state of the wheel based on the wheel slip rate and deceleration; Calculate and process the target braking force according to the state of the wheel; Filtering the target braking force according to the increase or decrease pressure status of the wheel; Finally, the air pressure ABS brake pressure is obtained.

7. A computer device comprising a processor and a memory, wherein the processor is connected to the memory, and the memory is used to store a computer program, wherein: The processor is used to execute the computer program stored in the memory, so that the computer device executes the pneumatic ABS brake pressure calculation method as claimed in claim 6.

8. A computer-readable storage medium, wherein a computer program is stored in the computer-readable storage medium, characterized in that: The computer program implements the pneumatic ABS brake pressure calculation method of claim 6 when executed.

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