AMT low-adhesion road surface anti-slip control system and method

Abstract

The invention provides an AMT low-adhesion road surface anti-slip control system and method.The sensor module comprises a wheel speed sensor, an inertial measurement unit and a temperature sensor; the data processing module performs data fusion by adopting an extended Kalman filtering algorithm, and outputs a vehicle speed v and a road surface friction coefficient mu; the control module comprises a gearbox control unit, an engine control unit and a brake system control unit. The method comprises the following steps: step 1, acquiring and processing data; step 2, engine torque limit control; step 3, gearbox gear selection and gear shifting control; and 4, brake system control and dynamic hydraulic adjustment are carried out. Through real-time monitoring of each dynamic parameter of the vehicle and multi-subsystem cooperative control, the anti-slip target of the vehicle under the low-adhesion condition is achieved, the safety and stability of the vehicle are improved, and good fuel economy and driving comfort are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of gearboxes, relates to AMT technology, and particularly relates to an AMT anti-slip control system and method for low-adhesion road surfaces. Background Art

[0002] With the continuous development of the commercial vehicle market, AMT (Automated Mechanical Transmission) has been widely applied to the power transmission systems of light and heavy commercial vehicles due to its advantages in improving fuel efficiency and reducing the driver's operation burden. However, on low-friction road conditions such as ice and snow roads, AMT faces great anti-slip challenges. Especially in working conditions such as starting, stepping on the accelerator, and stepping on the brake, the coordination between the gearbox, the engine, and the braking system is not precise enough, which easily leads to wheel slip and affects the stability and safety of the vehicle.

[0003] Currently, the technical development of anti-slip control for commercial vehicle AMT on ice and snow roads at home and abroad lags behind. The existing technologies mainly rely on the detection of wheel speed by a single sensor (such as a wheel speed sensor). When the vehicle starts, accelerates, or brakes on low-adhesion road surfaces such as ice, snow, and wet roads, it is easy to cause the anti-slip measures to react slowly or be executed inaccurately due to inaccurate detection, resulting in problems such as vehicle slip, power interruption, or unstable braking. At the same time, there is a lack of in-depth coordination between the traditional technology subsystems (engine, gearbox, braking system), making it difficult to achieve overall control and fault redundancy, and there are potential safety hazards. Summary of the Invention

[0004] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide an AMT anti-slip control system and method for low-adhesion road surfaces, and solve the technical problem that the anti-slip performance of existing commercial vehicle AMT on low-adhesion road surfaces needs to be further improved.

[0005] To solve the above technical problems, the present invention is implemented by adopting the following technical solutions:

[0006] An AMT anti-slip control system for low-adhesion road surfaces includes a sensor module, a data processing module, and a control module.

[0007] The sensor module includes a wheel speed sensor, an inertial measurement unit, and a temperature sensor; the wheel speed sensor, the inertial measurement unit, and the temperature sensor are respectively connected to the data processing module.

[0008] The data processing module uses an extended Kalman filter algorithm for data fusion and outputs the vehicle speed v and the road surface friction coefficient μ.

[0009] The described control module includes a transmission control unit, an engine control unit, and a brake system control unit. The transmission control unit, the engine control unit, and the brake system control unit are respectively connected to the data processing module, and the transmission control unit is also respectively connected to the engine control unit and the brake system control unit.

[0010] The present invention also protects an AMT anti-slip control method for low-adhesion road surfaces, which uses the AMT anti-slip control system for low-adhesion road surfaces as described above.

[0011] This method includes the following steps:

[0012] Step 1, data acquisition and processing:

[0013] The wheel speed sensor is used to collect high-frequency rotational speed data and obtain the theoretical wheel speed through conversion.

[0014] The inertial measurement unit is used to directly measure the vehicle longitudinal acceleration and obtain the vehicle speed through integral calculation.

[0015] The temperature sensor is used to collect the temperature to assist in judging the road surface ice and snow state.

[0016] The extended Kalman filter algorithm is used to fuse the theoretical wheel speed, vehicle speed, and temperature, and output the vehicle speed v and the road surface friction coefficient μ.

[0017] Step 2, engine torque limit control:

[0018] According to the vehicle speed v and the road surface friction coefficient μ obtained by real-time fusion in Step 1, based on the engine load and slope coupling torque limit method, the PID algorithm is used to adjust the engine output torque in real time, and after limiting the engine torque, it is executed by the engine control unit.

[0019] Step 3, transmission gear selection and shift control:

[0020] Step 301, starting gear and gear ratio selection:

[0021] The transmission control unit selects the starting gear and gear ratio according to the slip rate, road slope, and vehicle load detected in real time.

[0022] Step 302, shift control:

[0023] During the shift process, the transmission control unit judges the shift condition according to the real-time vehicle speed and engine speed, and sends a shift command through the hydraulic valve to execute the shift control strategy, the gear locking and skip-shifting strategy, and the skip-shifting strategy.

[0024] Step 303, clutch pressure adaptation.

[0025] Step 4, Braking System Control and Dynamic Hydraulic Regulation:

[0026] Step 401, Based on the vehicle speed v and wheel speed difference obtained by real-time fusion in Step 1, during the vehicle braking process, the braking system control unit uses PID closed-loop regulation of hydraulic pressure to keep the error between the actual braking pressure and the set target within ±3 Bar.

[0027] Step 402, According to the vehicle center of gravity information, the braking system control unit distributes the total braking force to the front axle and the rear axle through the front and rear braking force distribution formula.

[0028] Step 403, When local wheel slip is detected, the braking system control unit automatically triggers fuel cut-off control.

[0029] The present invention also has the following technical features:

[0030] In Step 2, the engine load and slope coupling torque limit method is: Torque limit value = [1 + (load level × 0.02) + (absolute value of road slope × 0.04)] × reference torque × friction coefficient.

[0031] In Step 2, the method for real-time adjustment of the engine output torque is: Torque change rate ≤ 200 N·m / s, and when the deviation between the actual output torque and the target torque exceeds 10%, a fault signal is fed back through the CAN bus to trigger safety measures; where: The calculation formula for the target torque is: Target torque = maximum torque × slip rate.

[0032] In Step 302, the shift control strategy is:

[0033] In the first gear, the duty ratio of the hydraulic valve is 80:20, and the shift delay is 500 milliseconds.

[0034] In the second gear, the duty ratio of the hydraulic valve is 60:40, and the shift delay is 400 milliseconds.

[0035] In the third gear, the duty ratio of the hydraulic valve is 30:70, and the shift delay is 300 milliseconds.

[0036] In Step 302, the gear locking and skip-shifting strategy is:

[0037] During the starting stage, upshifting is prohibited when the slip rate is greater than 8%.

[0038] During driving, the current gear is locked when the slip rate is greater than 12%.

[0039] During emergency braking, the gear is forced down to the first gear when the slip rate exceeds 15%.

[0040] In Step 302, the skip-shifting strategy is:

[0041] Shift speed threshold = Base shift speed × (1 + 0.15 × Compensation factor).

[0042] In step 303, the method for clutch pressure adaptation is: Adjusted clutch pressure = Reference clutch pressure × [1 - 0.1 × (Current slip rate × 0.2 + Current clutch temperature compensation coefficient)].

[0043] In step 402, the front and rear braking force distribution formula is: Front axle braking force = Front axle ratio × Total braking force, Rear axle braking force = (1 - Front axle ratio) × Total braking force, where the front axle ratio is set to 65% - 70%.

[0044] Compared with the prior art, the present invention has the following technical effects:

[0045] (Ⅰ) Through real-time monitoring of various vehicle dynamic parameters and coordinated control of multiple subsystems, the present invention achieves the goal of preventing vehicle skidding under low adhesion conditions, not only improving vehicle safety and stability, but also having good fuel economy and driving comfort, and having broad market application prospects.

[0046] (Ⅱ) The present invention improves data accuracy and real-time performance: Through multi-sensor data fusion and extended Kalman filtering, the actual vehicle speed and road surface friction coefficient can be accurately obtained, overcoming the problem of data distortion of a single sensor during skidding.

[0047] (Ⅲ) The present invention realizes deep coordination of the engine, transmission and braking system: The subsystems coordinate with each other through real-time data interaction and precise control instructions, enabling the vehicle to maintain stability during the entire process of starting, shifting, driving and braking, and significantly reducing the skidding risk caused by power mismatch.

[0048] (Ⅳ) The present invention has perfect safety redundancy and fault handling capabilities: When some sensor data is abnormal or communication is interrupted, the system can automatically switch to the safe mode and use redundant data for compensation to ensure the safe operation of the whole vehicle.

[0049] (Ⅴ) The present invention comprehensively considers vehicle dynamics characteristics and actual working conditions: In each control link of the present invention, parameters are set and dynamically adjusted according to actual vehicle dynamics, load, road gradient, environmental temperature and other factors, ensuring the scientificity and practicality of the system design. Description of the Drawings

[0050] Figure 1 It is a schematic diagram of the overall architecture of the AMT anti-skid control system for low adhesion road surfaces.

[0051] Figure 2 It is a schematic diagram of the process of the data processing module.

[0052] Figure 3 It is a schematic diagram of the parallel control process of the engine and the transmission.

[0053] Figure 4 It is a schematic diagram of the control process of the braking system.

[0054] The following further elaborates on the specific content of the present invention in conjunction with embodiments. Specific embodiments

[0055] It should be noted that all units, devices, and algorithms in the present invention, unless otherwise specified, all adopt the units, devices, and algorithms known in the prior art.

[0056] The following gives specific embodiments of the present invention. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent transformations made on the basis of the technical solutions of this application fall within the protection scope of the present invention.

[0057] Embodiment 1:

[0058] This embodiment provides an anti-slip control system for AMT on low-adhesion road surfaces, as Figure 1 shown, including a sensor module, a data processing module, and a control module.

[0059] As Figure 1 shown, the sensor module includes a wheel speed sensor, an inertial measurement unit (Inertial Measurement Uni, IMU), and a temperature sensor; the wheel speed sensor, the inertial measurement unit, and the temperature sensor are respectively connected to the data processing module.

[0060] As Figure 1 shown, the data processing module uses the Extended Kalman Filter (EKF) algorithm for data fusion and outputs the vehicle speed v and the road surface friction coefficient μ.

[0061] As Figure 1 shown, the control module includes a transmission control unit (Transmission Control Unit, TCU), an engine control unit (Engine Control Unit, ECU), and a braking system control unit (Electronic Stability Control, ESC). The transmission control unit, the engine control unit, and the braking system control unit are respectively connected to the data processing module, and the transmission control unit is also respectively connected to the engine control unit and the braking system control unit.

[0062] In this embodiment, the sensor module is used to collect vehicle operating status and environmental information.

[0063] In this embodiment, the inertial measurement unit adopts a commonly known inertial measurement unit in the art, and the inertial measurement unit can measure acceleration.

[0064] In this embodiment, the working process of the data processing module is as Figure 2 shown, Figure 2 which details how to collect data from each sensor and obtain accurate vehicle speed and friction coefficient after data conversion and fusion. Figure 2 The left side shows the raw data inputs of the wheel speed sensor, inertial measurement unit (IMU), and temperature sensor. The wheel speed sensor data converts the rotational speed to angular velocity through a conversion module and then calculates the vehicle speed in combination with the tire radius; the IMU directly outputs acceleration data; the temperature data helps to judge the road surface condition. All data is gathered into the data fusion module (EKF), and after algorithm processing, the vehicle speed v and the road surface friction coefficient μ are output.

[0065] In this embodiment, in the control module, each execution unit realizes real-time data intercommunication and instruction feedback through the CAN (Controller Area Network) bus / UDS (Unified Diagnostic Services) bus.

[0066] The overall system architecture diagram of this embodiment is as Figure 1 shown, Figure 1 which clearly shows the division of labor and cooperation in data collection, processing, and execution, ensuring the stable and safe operation of the system under complex working conditions, and at the same time reflecting the safety redundancy design. This is the working process of the anti-skid control strategy.

[0067] Embodiment 2:

[0068] This embodiment provides an AMT anti-skid control method for low-adhesion road surfaces, which adopts the AMT anti-skid control system given in Embodiment 1.

[0069] This method includes the following steps:

[0070] Step 1, data collection and processing:

[0071] The wheel speed sensor is used to collect high-frequency rotational speed data and obtain the theoretical wheel speed through conversion.

[0072] The inertial measurement unit is used to directly measure the vehicle longitudinal acceleration and obtain the vehicle speed through integration.

[0073] The temperature sensor is used to collect the temperature and assist in judging the ice and snow state of the road surface.

[0074] The wheel theoretical speed, vehicle speed, and temperature are fused using the Extended Kalman Filter (EKF) algorithm to output the vehicle speed v and the road surface friction coefficient μ.

[0075] Specifically in this embodiment, the specific process of data acquisition and processing is as follows:

[0076] Step 101, obtaining vehicle speed data:

[0077] Step 10101, obtaining wheel speed sensor data:

[0078] Each wheel is equipped with a wheel speed sensor that outputs the rotational speed (unit: revolutions per minute) in real time, and the data is transmitted through the CAN bus.

[0079] Convert the rotational speed data output by the wheel speed sensor into the angular velocity of the wheel. The conversion method is: angular velocity = rotational speed × 2π ÷ 60.

[0080] Calculate the theoretical vehicle speed according to the tire radius (for example, 0.5 meters, determined according to the vehicle configuration). The calculation formula is: vehicle speed = angular velocity × tire radius.

[0081] The wheel speed sensor has a fast response speed and a high update frequency, and can provide high-frequency dynamic data. However, in the case of wheel slip, the rotational speed of the driving wheel may be greater than the actual vehicle speed. Therefore, it is necessary to fuse and correct with other data.

[0082] Step 10102, fusing the data of the inertial measurement unit and the vehicle speed:

[0083] The inertial measurement unit directly provides the vehicle longitudinal acceleration (unit: m / s²), and the vehicle speed is calculated using integration. The formula is: vehicle speed (IMU) = initial vehicle speed + integral (acceleration × time).

[0084] To overcome the integral drift problem of the inertial measurement unit, the present invention uses the Extended Kalman Filter (EKF) to fuse the vehicle speed calculated by the wheel speed sensor and the vehicle speed obtained by integrating the inertial measurement unit to obtain a more accurate real-time vehicle speed. The data fusion combines the advantages of the two sensors, can make full use of the high-frequency data of the wheel speed sensor, and can compensate for the inaccuracy of the data in the case of wheel slip, thus providing accurate vehicle speed information for subsequent control.

[0085] Step 102, obtaining acceleration data:

[0086] Direct measurement using the inertial measurement unit: The inertial measurement unit directly measures the vehicle longitudinal acceleration (unit: m / s²).

[0087] Vehicle speed derivative method: Using the fused vehicle speed data, calculate the acceleration through numerical differentiation. The formula is: acceleration = differential of vehicle speed with respect to time.

[0088] To reduce noise interference, the vehicle speed data is usually low-pass filtered before differentiation.

[0089] Acceleration data is obtained by multiple methods, which can be mutually verified and fused to improve data accuracy and provide a reliable basis for engine and braking control.

[0090] Step 103, road surface condition detection and friction coefficient estimation:

[0091] Vehicle dynamics model: In this solution, the state vector is defined as: [vehicle speed, friction coefficient].

[0092] The vehicle speed update formula is described as: the vehicle speed at the next moment = the current vehicle speed + (actual acceleration - friction coefficient × gravitational acceleration) × sampling period + process noise.

[0093] The friction coefficient update formula is described as: the friction coefficient at the next moment = the current friction coefficient + process noise.

[0094] The above extended Kalman filter method can fuse high-frequency wheel speed data and inertial measurement unit data, make up for their respective limitations, accurately estimate the vehicle speed and friction coefficient, and provide a reliable basis for the subsequent dynamic control of the engine, transmission, and braking system.

[0095] Observation equation: The measured vehicle speed is equal to the vehicle speed in the state plus the measurement noise, which is described as: measured vehicle speed = vehicle speed + measurement noise, where the range of the measurement noise is about ±0.1 m / s.

[0096] Step two, engine torque limit control:

[0097] As Figure 3 shown, during the engine torque limit control process, first, driving mode compensation is required: according to the economic, standard, and sport driving modes, the engine torque response coefficient is adjusted, and an example is shown in Table 1.

[0098] Table 1 Driving mode compensation

[0099] Driving mode Torque response coefficient Shift delay (seconds) Braking sensitivity Economy mode 0.8 0.6 0.7 Standard mode 1.0 0.3 1.0 Sport mode 1.3 0.1 1.2

[0100] As Figure 3 shown, the specific process of step two is as follows:

[0101] Based on the vehicle speed v and road surface friction coefficient μ obtained by real-time fusion in step one, and based on the engine load and slope coupling torque limit method, the PID (proportional-integral-derivative control) algorithm is used to adjust the engine output torque in real time. After limiting the engine torque, it is executed by the engine control unit (ECU), and faults are detected and feedback in real time.

[0102] In step two, the method for coupling torque limit of engine load and slope is: torque limit value = [1 + (load level

[0103] × 0.02) + (absolute value of road slope × 0.04)] × reference torque × friction coefficient.

[0104] In this embodiment, the load level, the absolute value of the road slope, and the reference torque are all obtained by using commonly known methods in the art.

[0105] In step two, the method for real-time adjustment of the engine output torque is: torque change rate ≤ 200 N·m / s, and when the deviation between the actual output torque and the target torque exceeds 10%, a fault signal is fed back through the CAN bus to trigger safety measures; where: the calculation formula for the target torque is: target torque = maximum torque × slip ratio.

[0106] Specifically in this embodiment, the maximum torque is 600 N·m (based on the engine manufacturer's parameters);

[0107] Specifically in this embodiment, the slip ratio consists of proportional, integral, and differential controls, and its calculation formula is: PID (slip ratio) = (proportional coefficient × slip ratio error) + (integral coefficient × integral of slip ratio error) + (differential coefficient × derivative of slip ratio error). The proportional coefficient is taken as 50, the integral coefficient is taken as 10, and the differential coefficient is taken as 20 (all determined based on bench tests and engineering experience).

[0108] The real-time adjustment in this step can ensure that the engine output torque matches the road adhesion, prevent wheel slip caused by excessive power, and at the same time limit the torque change rate not to exceed the specified value to avoid sudden power changes.

[0109] The goal of the PID adjustment in this step is to control the engine output torque to match the road adhesion ability, thereby avoiding slip caused by excessive power.

[0110] Step three, gear selection and shift control of the gearbox:

[0111] As Figure 3 shown, during the gear selection and shift control of the gearbox, first, driving mode compensation is required: according to the economic, standard, and sport driving modes, the shift delay is adjusted, and examples are shown in Table 1.

[0112] As Figure 3 shown, the specific process of step three is:

[0113] Step 301, starting gear and gear ratio selection:

[0114] The transmission control unit (TCU) selects the starting gear and gear ratio according to the slip ratio, road slope, and vehicle load detected in real time.

[0115] In this embodiment, the calculation method of the slip ratio is the same as that in step 2. The detection methods for road gradient and vehicle load are both commonly used detection methods in the art.

[0116] A specific example in this embodiment is shown in Table 2.

[0117] Table 2 Starting Gear and Gear Ratio Selection

[0118] Slip ratio (%) Road gradient (%) Load (tons) Gear selection Gear ratio Less than 5 Less than 5 Less than 8 Third gear 2.5:1 5 to 10 5 to 10 8 to 12 Second gear 3.2:1 Greater than 10 Greater than 10 Greater than 12 First gear 4.5:1

[0119] Step 302, Shift control:

[0120] During the shifting process, the transmission control unit (TCU) determines the shifting conditions based on the real-time vehicle speed and engine speed, and sends a shifting command through the hydraulic valve to execute the shifting control strategy, gear locking and skip-shifting strategy, and skip-shifting strategy to ensure smooth shifting and avoid slippage caused by power interruption.

[0121] In this embodiment, when the slip ratio is low and the load is light, a high gear is selected to ensure fuel economy; when the slip ratio is high, a low gear is selected to amplify the effective torque of the engine to ensure sufficient traction. The calculation of traction is described as: Traction = (Engine output torque × Gear ratio) ÷ Tire radius.

[0122] In step 302, the shifting control strategy is:

[0123] When in the first gear, the duty ratio of the hydraulic valve is 80:20, and the shifting delay is 500 milliseconds.

[0124] When in the second gear, the duty ratio of the hydraulic valve is 60:40, and the shifting delay is 400 milliseconds.

[0125] When in the third gear, the duty ratio of the hydraulic valve is 30:70, and the shifting delay is 300 milliseconds.

[0126] In step 302, the gear locking and skip-shifting strategy is:

[0127] During the starting stage, upshifting is prohibited when the slip ratio is greater than 8%.

[0128] During driving, the current gear is locked when the slip ratio is greater than 12%.

[0129] During emergency braking, downshifting is forced to the first gear when the slip ratio exceeds 15%.

[0130] In step 302, the skip-shifting strategy is:

[0131] Shift speed threshold = Base shift speed × (1 + 0.15 × Compensation factor).

[0132] In this embodiment, the compensation factor is taken as 0.3.

[0133] Step 303, Clutch Pressure Adaptation:

[0134] The method of clutch pressure adaptation is: Adjusted clutch pressure = Reference clutch pressure

[0135] × [1 - 0.1×(Current slip ratio × 0.2 + Current clutch temperature compensation coefficient)].

[0136] In this embodiment, the reference clutch pressure is obtained by a commonly known method in the art.

[0137] In this embodiment, the current clutch temperature compensation coefficient = Current clutch temperature / 100°C.

[0138] In this embodiment, reasonably selecting the gear and gear ratio and precise shift control can amplify the effective torque of the engine under low adhesion conditions, improve the traction force, avoid power loss caused by shift interruption, and at the same time achieve the best power transmission matching through driving mode compensation.

[0139] Step Four, Brake System Control and Dynamic Hydraulic Regulation:

[0140] During the brake system control and dynamic hydraulic regulation process, first, driving mode compensation is performed: According to the economic, standard, and sport driving modes, the brake sensitivity is adjusted, as shown in Table 1 for example.

[0141] As Figure 4 shown, the specific process of Step Four is:

[0142] Step 401, Based on the vehicle speed v and wheel speed difference obtained by real-time fusion in Step One, during the vehicle braking process, the brake system control unit (ESC) uses PID closed-loop regulation of the hydraulic pressure to keep the actual braking pressure within ±3 Bar of the set target error.

[0143] Step 402, Based on the vehicle center of gravity information, the brake system control unit (ESC) distributes the total braking force to the front axle and the rear axle through the front and rear braking force distribution formula.

[0144] In Step 402, the front and rear braking force distribution formula is: Front axle braking force = Front axle ratio × Total braking force, Rear axle braking force = (1 - Front axle ratio) × Total braking force, where the front axle ratio is set to 65% - 70%, based on vehicle center of gravity analysis and the manufacturer's brake system design specifications.

[0145] Step 403, When local wheel slip is detected, the brake system control unit (ESC) automatically triggers fuel cut-off control to further prevent wheel lock-up and vehicle roll.

[0146] In this embodiment, the wheel speed difference is detected by using a commonly known method in the art. The vehicle center of gravity information is detected by using a commonly known method in the art.

[0147] In this embodiment, reasonably distributing the braking force and dynamically adjusting the hydraulic pressure can prevent the wheels from locking and rolling over, ensure the stability of the whole vehicle during braking, and meet the requirements of vehicle braking dynamics.

[0148] Step Five, System Coordination and Safety Redundancy Design:

[0149] The AMT anti-slip control system for low-adhesion road surfaces is equipped with a strict timing management and fault detection mechanism. When abnormal sensor data or communication timeout is detected (for example, no response for more than 500 milliseconds), the system automatically switches to the safe mode (such as downshifting, applying the maximum braking force, and setting the engine torque to zero), and uses redundant data (such as IMU data to compensate for wheel speed data) to ensure the continuous and stable operation of the system.

[0150] By designing an integrated and coordinated anti-slip control strategy and combining the deep integration and real-time control of the AMT, engine system, and braking system, the present invention can effectively improve the driving stability and safety of commercial vehicles on low-friction coefficient road surfaces. This strategy can significantly reduce the risk of wheel slip on low-friction roads and avoid more serious situations during slip conditions, and has strong application value and market prospects.

Claims

1. An AMT anti-skid control system for low-adhesion road surfaces, comprising a sensor module, a data processing module and a control module, characterized in that: The sensor module includes a wheel speed sensor, an inertial measurement unit and a temperature sensor; the wheel speed sensor, the inertial measurement unit and the temperature sensor are respectively connected to the data processing module; The data processing module uses the extended Kalman filter algorithm for data fusion and outputs the vehicle speed v and the road surface friction coefficient μ; The control module includes a transmission control unit, an engine control unit, and a braking system control unit. The transmission control unit, the engine control unit, and the braking system control unit are respectively connected to the data processing module, and the transmission control unit is also respectively connected to the engine control unit and the braking system control unit.

2. An anti-skid control method for AMT on low-adhesion road surfaces, characterized in that, This method uses the AMT anti-skid control system for low-adhesion road surfaces as described in claim 1; This method includes the following steps: Step 1, data acquisition and processing: The wheel speed sensor is used to collect high-frequency rotation speed data and obtain the theoretical wheel speed through conversion; The inertial measurement unit is used to directly measure the vehicle longitudinal acceleration and obtain the vehicle speed through integral calculation; The temperature sensor is used to collect the temperature to assist in judging the road surface ice and snow state; The extended Kalman filter algorithm is used to fuse the theoretical wheel speed, vehicle speed and temperature, and output the vehicle speed v and the road surface friction coefficient μ; Step 2, engine torque limit control: According to the vehicle speed v and the road surface friction coefficient μ obtained by real-time fusion in Step 1, based on the engine load and slope coupling torque limit method, the PID algorithm is used to adjust the engine output torque in real time, and after limiting the engine torque, it is executed by the engine control unit; Step 3, transmission gear selection and shift control: Step 301, starting gear and gear ratio selection: The transmission control unit selects the starting gear and gear ratio according to the slip rate, road slope and vehicle load detected in real time; Step 302, shift control: During the shift process, the transmission control unit judges the shift condition according to the real-time vehicle speed and engine speed, and sends a shift command through the hydraulic valve to execute the shift control strategy, lock gear and skip gear strategy, and skip gear shift strategy; Step 303, clutch pressure adaptation; Step 4, braking system control and dynamic hydraulic regulation: Step 401, according to the vehicle speed v and the wheel speed difference obtained by real-time fusion in Step 1, the braking system control unit uses the PID closed-loop regulation of the hydraulic pressure during the vehicle braking process to keep the actual braking pressure within ±3Bar of the set target error; Step 402, according to the vehicle center of gravity information, the braking system control unit distributes the total braking force to the front axle and the rear axle through the front and rear braking force distribution formula; Step 403, when local wheel slip is detected, the braking system control unit automatically triggers fuel cut-off control.

3. The AMT anti-slip control method for low-adhesion road surfaces according to claim 2, wherein In Step 2, the engine load and slope coupling torque limit method is: torque limit value = [1 + (load level × 0.02) + (absolute value of road slope × 0.04)] × reference torque × friction coefficient.

4. The AMT anti-slip control method for low-adhesion road surfaces according to claim 2, wherein In step 2, the method for real-time adjustment of the engine output torque is as follows: the torque change rate ≤ 200 N·m / s, and when the deviation between the actual output torque and the target torque exceeds 10%, a fault signal is fed back through the CAN bus to trigger safety measures; where: the calculation formula for the target torque is: target torque = maximum torque × slip ratio.

5. The AMT anti-slip control method for low-adhesion road surfaces according to claim 2, characterized in that, In step 302, the shift control strategy is as follows: When in the first gear, the duty ratio of the hydraulic valve is 80:20, and the shift delay is 500 milliseconds; When in the second gear, the duty ratio of the hydraulic valve is 60:40, and the shift delay is 400 milliseconds; When in the third gear, the duty ratio of the hydraulic valve is 30:70, and the shift delay is 300 milliseconds.

6. The AMT anti-slip control method for low-adhesion road surfaces according to claim 2, characterized in that In step 302, the gear locking and skip-shifting strategy is as follows: When starting, upshifting is prohibited when the slip ratio is greater than 8%; During driving, the current gear is locked when the slip ratio is greater than 12%; When emergency braking, the gear is forced to downshift to the first gear when the slip ratio exceeds 15%.

7. The AMT anti-slip control method for low-adhesion road surfaces according to claim 2, wherein In step 302, the skip-shifting strategy is: the shift speed threshold = base shift speed × (1 + 0.15 × compensation factor).

8. The AMT anti-slip control method for low-adhesion road surfaces according to claim 2, characterized in that, In step 303, the method for clutch pressure adaptation is: adjusted clutch pressure = reference clutch pressure × [1 - 0.1 × (current slip ratio × 0.2 + current clutch temperature compensation coefficient)].

9. The AMT anti-slip control method for low-adhesion road surfaces according to claim 2, wherein, In step 402, the front and rear braking force distribution formula is: front axle braking force = front axle ratio × total braking force, rear axle braking force = (1 - front axle ratio) × total braking force, where the front axle ratio is set to 65% - 70%.

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