Commercial vehicle main-mounted five-in-one integrated brake-by-wire system

Abstract

The invention discloses a commercial vehicle main-mounted five-in-one integrated brake-by-wire system which is highly integrated by a central controller, an ESC module, a front axle controller, a rear axle controller and a trailer TEBS controller and is uniformly integrated to a central ECU. The central ECU makes a unified decision to directly drive the front and rear axle electromagnetic valves; the central ECU carries out logic judgment and decision making in a unified mode and then directly carries out trailer electromagnetic valve driving by sending an electromagnetic valve control instruction to the trailer TEBS controller, and finally main and trailer integrated control is achieved; the central ECU directly drives the corresponding electromagnetic valves to act after recognizing the braking requirement, CAN signal transmission is not needed, and the system response time is greatly shortened. According to the five-in-one integrated brake-by-wire system, high integration of the main vehicle and integrated control of the main vehicle and the hanging vehicle are achieved, and the higher requirement of a commercial vehicle brake-by-wire system can be met.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of commercial vehicle line control braking, and relates to a commercial vehicle main-hang five-in-one integrated line control braking system. BACKGROUND

[0002] The commercial vehicle line control braking system is an EBS (Electronic Braking Systems) system, a central controller identifies the braking intention and braking demand of a driver according to a pedal displacement signal captured by a foot valve displacement sensor, and sends the estimated braking demand to a front axle module and a rear axle module through a private CAN line, and a system central control module of a trailer TEBS (Electronic Braking Systems for Trailers) needs to send a target deceleration instruction to a trailer module at the same time, and the front axle controller, the rear axle controller and the trailer controller make self-decision after receiving the target deceleration braking instruction, control corresponding electromagnetic valves to realize electronic control functions.

[0003] At present, the central control module and the ESC sensor of the KNORR EBS system integrated version are integrated and installed at the vehicle beam centroid position, the wire harness connection from the central controller to the ESC sensor is saved, the system failure rate is reduced to a certain extent while the cost is saved, the central controller, the ESC and the rear axle module of the WABCO EBS system integrated version are integrated in one body, the cost is further reduced, and the system reliability is further improved. Although the two mainstream EBS manufacturers above have carried out certain integration in the tractor, the integration degree is limited, and the trailer still adopts a distributed structure, so that the overall integration degree of the system is low. SUMMARY

[0004] In view of the problems in the prior art, the purpose of the present application is to provide a commercial vehicle main-hang five-in-one integrated line control braking system, which solves the problem of low overall integration degree of the current main-hang EBS system, and the present application is a five-in-one integrated line control braking system in which the central controller, the ESC module, the front axle controller, the rear axle controller and the trailer TEBS controller are highly integrated, the main vehicle is highly integrated, and the main-hang integrated control is realized to meet the higher requirements of the future commercial vehicle line control braking system.

[0005] In order to solve the above technical problems, the present application adopts the following technical solutions: A commercial vehicle main-hang five-in-one integrated line control braking system, in which the central controller, the ESC module, the front axle controller in the front axle module, the rear axle controller in the rear axle module and the trailer TEBS controller of the trailer module are highly integrated and unified to the central ECU, and the system further comprises a brake foot valve module. The central ECU is directly connected by hard wire to the front and rear axle intake solenoid valves, exhaust solenoid valves, backup pressure solenoid valves, front and rear axle wheel speed sensors, and front and rear axle built-in air pressure sensors of the front and rear axle modules; the front and rear axle modules only act as actuators to realize the corresponding solenoid valve actions and do not participate in logical judgment and decision-making. The central ECU makes unified decisions and directly drives each solenoid valve of the front and rear axle modules. After the central ECU performs unified logical judgment and decision-making, it sends solenoid valve control commands to the trailer TEBS controller. The trailer TEBS controller does not need to make logical judgments and directly drives the solenoid valves according to the commands, realizing integrated control of the master and trailer.

[0006] The present invention also includes the following technical features: Specifically, the central ECU has five connectors: X1, X2, X3, X4 and X5. X1 connector connects to the front axle module; X2 connector connects to the brake foot valve module; X3 connector connects to the trailer TEBS controller for power supply and CAN communication; X4 connector is the power supply interface for the central ECU; X5 connector connects to the rear axle module.

[0007] Specifically, the X1 connector of the central ECU is directly connected to the intake solenoid valve, exhaust solenoid valve, and backup pressure solenoid valve of the front axle via a hard wire; the X1 connector of the central ECU is directly connected to the built-in air pressure sensor of the front axle via a hard wire; the X1 connector of the central ECU is directly connected to the left wheel speed sensor and the right wheel speed sensor of the front axle via a hard wire; the central controller directly drives and controls each solenoid valve of the front axle module.

[0008] Specifically, the X2 connector of the central ECU is hardwired to the brake foot valve module to transmit the foot pedal displacement signal monitored in real time by the two BST displacement sensors and the brake pedal switch signal determined by the single-pole double-position switch of the foot valve. The central ECU identifies the driver's braking needs based on the displacement signal and then allocates reasonable brake air pressure to the front and rear axles and trailer modules.

[0009] Specifically, the X3 connector of the central ECU is connected to the trailer TEBS controller, and the connection line includes a power supply harness and a CAN line; the power supply harness is used to supply power to the trailer module, and the CAN line is used for CAN communication between the master vehicle and the trailer.

[0010] Specifically, the X4 connector of the central ECU is a power supply interface, which is connected to the 30V power supply, 15V power supply and the vehicle CAN bus.

[0011] Specifically, the X5 connector of the central ECU is directly connected by a hard wire to the left intake solenoid valve, left exhaust solenoid valve, and left backup pressure solenoid valve of the rear axle; the X5 connector of the central ECU is directly connected by a hard wire to the right intake solenoid valve, right exhaust solenoid valve, and right backup pressure solenoid valve of the rear axle; the X5 connector of the central ECU is directly connected by a hard wire to the left and right built-in air pressure sensors of the rear axle; the X5 connector of the central ECU is directly connected by a hard wire to the left and right wheel speed sensors of the rear axle; the central controller directly drives and controls the left and right solenoid valves of the rear axle module.

[0012] The control method for the commercial vehicle driver-trailer five-in-one integrated drive-by-wire system includes the following steps: Step 1: Power the system through the X4 connector. After power is supplied, the driver presses the brake pedal. Step 2: Two BST displacement sensors monitor the pedal displacement changes in real time. The foot valve single-pole double-switch determines whether the brake pedal switch has flipped and transmits the displacement signal and switch signal to the central ECU. The two BST displacement signals are mutually verified and redundant. When both displacement signals are normal, the average value is selected as the input for driver intention recognition. When one signal fails, the other signal is selected as the intention recognition input. Step 3: The central ECU identifies the driver's braking intention based on the signals from Step 2. It determines whether the driver has pressed the brake pedal based on the two switch signals, and judges the driver's braking demand based on the PWM value of the pedal displacement. The larger the displacement, the greater the braking demand. At the same time, the derivative of the pedal displacement PWM is calculated to obtain the pedal speed. When the pedal speed is greater than the threshold, it is considered that the driver has an emergency braking demand. At this time, even if the driver does not press the brake pedal all the way down, the braking force is still distributed according to the maximum air pressure of the air tank. Based on the above driver braking intention identification, the braking force required by the front and rear axles and the trailer is automatically and uniformly distributed. Step 4: Based on the braking force allocated in Step 3, the central ECU performs the corresponding actions. It directly drives the corresponding solenoid valve of the front axle via the X1 hard wire; it directly drives the corresponding solenoid valve of the rear axle via the X5 hard wire; and it sends solenoid valve control commands to the trailer TEBS controller via the X3 CAN line until the target braking requirement is achieved. Step 5: After receiving the solenoid valve control command in Step 4, the trailer TEBS controller drives the corresponding solenoid valve to operate through its internal hardware circuit to achieve the braking requirement. Step 6: After the system brakes in Step 4, the front axle wheel speed sensor transmits the wheel speed signal to the central ECU in real time via hard wire X1; the rear axle wheel speed sensor transmits the wheel speed signal to the central ECU in real time via hard wire X5; the trailer wheel speed signal is collected by the TEBS controller and forwarded to the central ECU via the X3 CAN line. Step 7: The central ECU processes the wheel speed signals from Step 6 and determines whether each wheel has a tendency to lock up. If the front and rear axles have a tendency to lock up, the ECU directly controls the solenoid valves of the front and rear axles accordingly. If the trailer has a tendency to lock up, the ECU sends a solenoid valve control command to the trailer TEBS controller. If there is no tendency to lock up, the ECU returns to Step 1 and repeats Steps 1-7 continuously.

[0013] Specifically, the determination of wheel lock-up tendency in step 7 is based on wheel slip ratio. and wheel deceleration ; The slip ratio is determined as follows: The slip ratio calculation formula is as follows: 100%……………………………………………(1) In the above formula, Indicates vehicle slip ratio, For vehicle speed, The wheel speed; in the case of pure rolling without any locking, slip ratio =0; when the wheels are completely locked and skidding. =0, slip ratio =100%; when the wheels are locked. The greater the tendency to lock, the greater the slip ratio; The wheel deceleration determination is specifically as follows: wheel speed deceleration is calculated by differentiating the wheel speed signal. When the road surface adhesion coefficient is... At that time, the maximum deceleration that the road surface can provide is , 9.8 m / s 2 When deceleration At that time, it was determined that the wheel speed showed a tendency to lock up, and The larger the size, the more severe the tendency to clump together. The system determines the deadlock trend based on the above two parameters, and the judgment condition is an AND relationship.

[0014] Compared with the prior art, the present invention has the following technical effects: (1) High integration of the main vehicle in this invention: The high-integration commercial vehicle main and trailer five-in-one control braking system integrates the main vehicle central controller, front axle controller, rear axle controller, and ESC module into a central ECU. The integrated central ECU is directly connected by hardwire to the front and rear axle intake solenoid valves, exhaust solenoid valves, backup pressure solenoid valves, front and rear axle wheel speed sensors, and front and rear axle built-in air pressure sensors. The front and rear axle modules only act as actuators to realize the corresponding solenoid valve actions and do not participate in logical judgment and decision-making. The central ECU makes unified decisions and directly drives the front and rear axle solenoid valves after the decision.

[0015] (2) Integrated master-trailer control in this invention: Traditional trailer TEBS still adopts a distributed structure, with the TEBS module being relatively independent. The master vehicle's EBS sends braking requirements to the TEBS module via a private CAN bus, and the TEBS makes its own decisions to respond to the braking requirements. The integrated five-in-one control braking system integrates the master and trailer control units, greatly simplifying the original trailer TEBS controller. Considering the long distance between the trailer wheel speed sensor and the master vehicle's central ECU, in order to reduce the disturbance of long-distance transmission of signals such as wheel speed and air pressure, the TEBS module only retains basic circuits such as wheel speed and air pressure signal acquisition, solenoid valve drive, and CAN transceiver. The remaining circuit modules are integrated with the central ECU. After the central ECU performs unified logical judgment and decision-making, it sends solenoid valve control commands to the TEBS. The TEBS does not need to perform logical judgment and directly drives the solenoid valve according to the commands, realizing integrated master-trailer control.

[0016] (3) The system response of the present invention is more agile: The central ECU of the five-in-one integrated brake-by-wire system proposed in this invention is directly connected to the front and rear axle solenoid valves via hard wires. After the central ECU identifies the braking demand, it directly drives the corresponding solenoid valve to act without the need for CAN signal transmission, which greatly shortens the system response time. At the same time, the wheel speed signals of the front and rear axles of the main vehicle are directly connected to the central ECU via hard wires, eliminating the forwarding delay of the CAN module. When wheel lock-up occurs, the anti-lock braking function of the main vehicle can be adjusted first to avoid major accidents such as trailer understeer caused by the main vehicle lock-up, and greatly improve the performance of ABS anti-lock braking.

[0017] (4) The cost of the present invention is greatly reduced: The central ECU of the five-in-one integrated brake-by-wire system for commercial vehicles is highly integrated. The front axle controller, rear axle controller, ESC sensor and trailer TEBS controller of the main vehicle are all highly integrated with the central ECU. The power management chip, voltage regulator chip and other components are reduced from five to one. The original CAN transceiver modules of the front and rear axles are eliminated. At the same time, the TEBS is only used as the execution unit. When a fault occurs, the replacement cost is greatly reduced. The operation and maintenance cost of the whole system is greatly reduced. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the five-in-one integrated brake-by-wire system for commercial vehicles of the present invention. Detailed Implementation

[0019] The following are specific embodiments of the present invention. It should be noted that the present invention is not limited to the following specific embodiments. All equivalent modifications made based on the technical solutions of this application fall within the protection scope of the present invention.

[0020] Example: This embodiment provides a five-in-one integrated drive-by-wire braking system for commercial vehicles, such as... Figure 1The system integrates the central controller, ESC module, front axle controller of the front axle module, rear axle controller of the rear axle module, and trailer TEBS controller of the trailer module, and unifies them into the central ECU. The system also includes a brake foot valve module. The ESC module is fully integrated into the central ECU, while the other modules only have integrated controllers and not integrated valve bodies.

[0021] The central ECU is directly connected by hardwire to the front and rear axle modules, including the intake solenoid valves, exhaust solenoid valves, backup pressure solenoid valves, wheel speed sensors, and built-in air pressure sensors. The front and rear axle modules act only as actuators to perform the corresponding solenoid valve actions and do not participate in logical judgment or decision-making. The central ECU makes unified decisions and directly drives the solenoid valves of the front and rear axle modules.

[0022] After the central ECU performs unified logical judgment and decision-making, it sends solenoid valve control commands to the trailer TEBS controller. The trailer TEBS controller does not need to make logical judgments and directly drives the solenoid valves according to the commands, realizing integrated control of the master and trailer.

[0023] The central ECU has five connectors: X1, X2, X3, X4 and X5. The X1 connector connects to the front axle module; the X2 connector connects to the brake foot valve module (BST), used to receive foot valve displacement signals; the X3 connector connects to the trailer TEBS controller power supply harness and CAN line, used to power the trailer TEBS controller and for CAN communication; the X4 connector is the central ECU power supply interface, connected to the 30V, 15V and vehicle CAN1 lines; and the X5 connector connects to the rear axle module.

[0024] The integrated central ECU's X1 connector is directly wired to the front axle's intake solenoid valve, exhaust solenoid valve, and reserve pressure solenoid valve; the central ECU's X1 connector is also directly wired to the front axle's built-in air pressure sensor; the central ECU's X1 connector is also directly wired to the front axle's left and right wheel speed sensors; the highly integrated mainframe front axle module only acts as an actuator to implement the corresponding solenoid valve actions, without participating in logical judgments or decisions, and the central controller directly drives and controls each solenoid valve of the front axle module.

[0025] The integrated central ECU's X2 connector is hardwired to the BST module. It is mainly used to transmit the pedal displacement signal monitored in real time by the two BST displacement sensors and the brake pedal switch signal determined by the foot valve single-pole double-position switch. The central ECU identifies the driver's braking needs based on the displacement signal and then distributes reasonable brake air pressure to the front and rear axles and trailer modules.

[0026] The integrated central ECU's X3 connector connects to the trailer TEBS controller, i.e., the trailer TEBS. The connection lines include a power supply harness and a CAN line; the solid line is the TEBS power supply harness, used to power the TEBS module, and the dashed line is the CAN line, used for CAN communication between the tractor and the trailer.

[0027] The integrated central ECU's X4 connector is the power supply interface, connecting to the 30V, 15V, and vehicle CAN bus, etc. The EBS node can communicate with other nodes on the bus via broadcast.

[0028] The integrated central ECU's X5 connector is directly wired to the left intake solenoid valve, left exhaust solenoid valve, and left reserve pressure solenoid valve of the rear axle; the integrated central ECU's X5 connector is also directly wired to the right intake solenoid valve, right exhaust solenoid valve, and right reserve pressure solenoid valve of the rear axle; the central ECU's X5 connector is directly wired to the left and right built-in air pressure sensors of the rear axle; and the central ECU's X5 connector is directly wired to the left and right wheel speed sensors of the rear axle. The main vehicle's rear axle module only acts as an actuator to perform the corresponding solenoid valve actions, while the central controller directly drives and controls the left and right solenoid valves of the rear axle module.

[0029] The control method of the commercial vehicle driver-trailer five-in-one integrated drive-by-wire braking system of the present invention includes the following steps: Step 1: Power the EBS system through the X4 connector. After power is supplied, the driver presses the brake foot valve (BST). Step 2: Two BST displacement sensors monitor the pedal displacement changes in real time. The foot valve single-pole double-switch determines whether the brake pedal switch has flipped. The simply processed displacement signal is transmitted to the central ECU in PWM pulse width mode via the X2 wiring harness. The switch signal is transmitted to the central ECU in high and low level mode via the X2 wiring harness. The two BST displacement signals are mutually verified and redundant. When both displacement signals are normal, the average value is selected as the input for driver intention recognition. When one fails, the other is selected as the intention recognition input. The two switch signals are always mutually exclusive and mutually verified.

[0030] Step 3: The central ECU identifies the driver's braking intention based on the two displacement sensor PWM signals and two toggle switch signals from Step 2. It determines whether the driver has pressed the brake pedal based on the two switch signals. Specifically, the two pedal switches default to 1 and 0. When the switch signals toggle (becoming 0 and 1), it indicates the brake pedal is pressed; when they return to their default state (becoming 1 and 0), it indicates the brake pedal is released. The magnitude of the pedal displacement PWM indicates the driver's braking demand; a larger displacement indicates a greater braking demand. The derivative of the pedal displacement PWM yields the pedal rate. When the pedal rate exceeds a certain threshold, it is considered that the driver has an emergency braking demand. In this case, even if the driver does not fully depress the brake pedal, braking force is still distributed according to the maximum air pressure in the air reservoir. Based on the above driver braking intention identification, the system automatically distributes the required braking force to the front and rear axles and the trailer.

[0031] Step 4: The system performs corresponding actions based on the braking force allocated in Step 3. The central ECU directly drives the corresponding solenoid valve of the front axle via the X1 hard wire; directly drives the corresponding solenoid valve of the rear axle via the X5 hard wire; and sends solenoid valve control commands to the trailer TEBS controller / TEBS module via the X3 CAN line until the target braking requirement is achieved.

[0032] Step 5: After receiving the solenoid valve control command in Step 4, the trailer TEBS controller / TEBS module drives the corresponding solenoid valve to operate through its internal hardware circuit to achieve the braking requirement. Step 6: In Step 4, the front axle wheel speed sensor transmits the wheel speed signal to the central ECU in real time via hard wire X1; the rear axle wheel speed sensor transmits the wheel speed signal to the central ECU in real time via hard wire X5; the trailer wheel speed signal is collected by the TEBS controller and then forwarded to the central ECU via the X3 CAN line.

[0033] Step 7: The central ECU processes the wheel speed signals from each module in Step 6 and determines whether each wheel has a tendency to lock up. If the front and rear axles have a tendency to lock up, the ECU directly controls the solenoid valves of the front and rear axles accordingly. If the trailer has a tendency to lock up, the ECU sends a solenoid valve control command to the trailer TEBS controller via a message. If there is no tendency to lock up, the ECU returns to Step 1 and repeats Steps 1-7 continuously.

[0034] The determination of wheel lock-up tendency in step 7 is mainly based on wheel slip ratio. and wheel deceleration The slip ratio determination is specifically based on the wheel speed signals of each wheel. Calculating reference vehicle speed using the comprehensive method Furthermore, the slip ratio is calculated based on the wheel speed signals of each wheel. The slip ratio calculation formula is as follows: 100%……………………………………………(1) In the above formula, Indicates vehicle slip ratio, For vehicle speed, The wheel speed; in the case of pure rolling without any locking, slip ratio =0; when the wheels are completely locked and skidding. =0, slip ratio =100%; when the wheels are locked to a certain extent As the tendency to lock up increases, the slip ratio also increases. To make reasonable use of road surface adhesion, this paper sets the slip ratio threshold to 18%. When the percentage is greater than 18%, it is considered that the wheels are prone to locking up.

[0035] Secondly, to improve the accuracy and real-time performance of wheel lock-up trend detection, wheel speed deceleration is introduced. The wheel deceleration determination is specifically as follows: wheel speed deceleration is determined by differentiating the wheel speed signal. When the road surface adhesion coefficient is... At that time, the maximum deceleration that the road surface can provide is , 9.8 m / s 2 When deceleration At that time, it was determined that the wheel speed showed a tendency to lock up, and The larger the size, the more severe the tendency to clump together. The system determines the deadlock trend based on the above two parameters, and the judgment condition is an AND relationship.

[0036] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0037] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0038] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A five-in-one integrated drive-by-wire braking system for commercial vehicles, characterized in that, The system integrates the central controller, ESC module, front axle controller in the front axle module, rear axle controller in the rear axle module, and trailer TEBS controller in the trailer module, and integrates them into the central ECU. The system also includes a brake foot valve module. The central ECU is directly connected by hard wire to the front and rear axle intake solenoid valves, exhaust solenoid valves, backup pressure solenoid valves, front and rear axle wheel speed sensors, and front and rear axle built-in air pressure sensors of the front and rear axle modules; the front and rear axle modules only act as actuators to realize the corresponding solenoid valve actions and do not participate in logical judgment and decision-making. The central ECU makes unified decisions and directly drives each solenoid valve of the front and rear axle modules. After the central ECU performs unified logical judgment and decision-making, it sends solenoid valve control commands to the trailer TEBS controller. The trailer TEBS controller does not need to make logical judgments and directly drives the solenoid valves according to the commands, realizing integrated control of the master and trailer.

2. The commercial vehicle driver-trailer five-in-one integrated drive-by-wire system as described in claim 1, characterized in that, The central ECU has five connectors: X1, X2, X3, X4 and X5. X1 connector connects to the front axle module; X2 connector connects to the brake foot valve module; X3 connector connects to the trailer TEBS controller for power supply and CAN communication; X4 connector is the power supply interface for the central ECU; X5 connector connects to the rear axle module.

3. The commercial vehicle driver-trailer five-in-one integrated drive-by-wire system as described in claim 2, characterized in that, The X1 connector of the central ECU is directly connected to the intake solenoid valve, exhaust solenoid valve, and backup pressure solenoid valve of the front axle via a hard wire; the X1 connector of the central ECU is directly connected to the built-in air pressure sensor of the front axle via a hard wire; the X1 connector of the central ECU is directly connected to the left wheel speed sensor and the right wheel speed sensor of the front axle via a hard wire; the central controller directly drives and controls each solenoid valve of the front axle module.

4. The commercial vehicle driver-trailer five-in-one integrated drive-by-wire system as described in claim 2, characterized in that, The X2 connector of the central ECU is hardwired to the brake foot valve module to transmit the foot pedal displacement signal monitored in real time by the two BST displacement sensors and the brake pedal switch signal determined by the single-pole double-position switch of the foot valve. The central ECU identifies the driver's braking needs based on the displacement signal and then allocates reasonable brake air pressure to the front and rear axles and trailer modules.

5. The commercial vehicle driver-trailer five-in-one integrated drive-by-wire system as described in claim 2, characterized in that, The X3 connector of the central ECU is connected to the trailer TEBS controller. The connection includes a power supply harness and a CAN line. The power supply harness is used to power the trailer module, and the CAN line is used for CAN communication between the tractor and the trailer.

6. The commercial vehicle driver-trailer five-in-one integrated drive-by-wire system as described in claim 2, characterized in that, The X4 connector of the central ECU is a power supply interface, which connects to the 30V power supply, 15V power supply and the vehicle CAN bus.

7. The commercial vehicle driver-trailer five-in-one integrated drive-by-wire system as described in claim 2, characterized in that, The X5 connector of the central ECU is directly connected by a hard wire to the left intake solenoid valve, left exhaust solenoid valve, and left backup pressure solenoid valve of the rear axle; the X5 connector of the central ECU is directly connected by a hard wire to the right intake solenoid valve, right exhaust solenoid valve, and right backup pressure solenoid valve of the rear axle; the X5 connector of the central ECU is directly connected by a hard wire to the left and right built-in air pressure sensors of the rear axle; the X5 connector of the central ECU is directly connected by a hard wire to the left and right wheel speed sensors of the rear axle; the central controller directly drives and controls the left and right solenoid valves of the rear axle module.

8. The control method of the commercial vehicle driver-trailer five-in-one integrated drive-by-wire braking system according to any one of claims 2 to 7, characterized in that, Includes the following steps: Step 1: Power the system through the X4 connector. After power is supplied, the driver presses the brake pedal. Step 2: Two BST displacement sensors monitor the pedal displacement changes in real time. The foot valve single-pole double-switch determines whether the brake pedal switch has flipped and transmits the displacement signal and switch signal to the central ECU. The two BST displacement signals are mutually verified and redundant. When both displacement signals are normal, the average value is selected as the input for driver intention recognition. When one signal fails, the other signal is selected as the intention recognition input. Step 3: The central ECU identifies the driver's braking intention based on the signals from Step 2. It determines whether the driver has pressed the brake pedal based on the two switch signals, and judges the driver's braking demand based on the PWM value of the pedal displacement. The larger the displacement, the greater the braking demand. At the same time, the derivative of the pedal displacement PWM is calculated to obtain the pedal speed. When the pedal speed is greater than the threshold, it is considered that the driver has an emergency braking demand. At this time, even if the driver does not press the brake pedal all the way down, the braking force is still distributed according to the maximum air pressure of the air tank. Based on the above driver braking intention identification, the braking force required by the front and rear axles and the trailer is automatically and uniformly distributed. Step 4: Based on the braking force allocated in Step 3, the central ECU performs the corresponding actions. It directly drives the corresponding solenoid valve of the front axle via the X1 hard wire; it directly drives the corresponding solenoid valve of the rear axle via the X5 hard wire; and it sends solenoid valve control commands to the trailer TEBS controller via the X3 CAN line until the target braking requirement is achieved. Step 5: After receiving the solenoid valve control command in Step 4, the trailer TEBS controller drives the corresponding solenoid valve to operate through its internal hardware circuit to achieve the braking requirement. Step 6: After the system brakes in Step 4, the front axle wheel speed sensor transmits the wheel speed signal to the central ECU in real time via hard wire X1; the rear axle wheel speed sensor transmits the wheel speed signal to the central ECU in real time via hard wire X5; the trailer wheel speed signal is collected by the TEBS controller and forwarded to the central ECU via the X3 CAN line. Step 7: The central ECU processes the wheel speed signals from Step 6 and determines whether each wheel has a tendency to lock up. If the front and rear axles have a tendency to lock up, the ECU directly controls the solenoid valves of the front and rear axles accordingly. If the trailer has a tendency to lock up, the ECU sends a solenoid valve control command to the trailer TEBS controller. If there is no tendency to lock up, the ECU returns to Step 1 and repeats Steps 1-7 continuously.

9. The control method for the commercial vehicle driver-trailer five-in-one integrated drive-by-wire braking system as described in claim 8, characterized in that, The determination of wheel lock-up tendency in step 7 is based on wheel slip ratio. and wheel deceleration ; The slip ratio is determined as follows: The slip ratio calculation formula is as follows: 100%……………………………………………(1) In the above formula, Indicates vehicle slip ratio, For vehicle speed, The wheel speed; in the case of pure rolling without any locking, slip ratio =0; when the wheels are completely locked and skidding. =0, slip ratio =100%; when the wheels are locked. The greater the tendency to lock, the greater the slip ratio; The wheel deceleration determination is specifically as follows: wheel speed deceleration is calculated by differentiating the wheel speed signal. When the road surface adhesion coefficient is... At that time, the maximum deceleration that the road surface can provide is , 9.8 m / s 2 When deceleration At that time, it was determined that the wheel speed showed a tendency to lock up, and The larger the size, the more severe the tendency to clump together. The system determines the deadlock trend based on the above two parameters, and the judgment condition is an AND relationship.

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