An electromechanical brake base brake (BBF) control method and device

Abstract

The application discloses an electromechanical brake base brake (BBF) control method and device. The application comprises the following steps: synchronously collecting multiple pedal signals, completing effectiveness screening and consistency cross-checking, and dynamically arbitrating output of a reliable braking intention according to the number of effective signals. Two controllers independently and in parallel solve a target braking torque, and output a consistent torque instruction after filtering, limiting and comparing the results. The target torque is distributed to each wheel end unit in combination with a braking working condition, the wheel end relies on local feedback to close loop adjust the torque, and the local autonomous mode is switched to continuously brake when the bus is abnormal. The application identifies a fault level in real time and enables a corresponding degradation strategy, and when digital signals and communication are all invalid, a fixed deceleration blind brake is triggered through a hardware loop. The application realizes multi-level redundancy of signals, controllers and execution layers, a multi-layer fault bottom mechanism, and significantly improves the functional safety level of the braking system.

Description

Technical Field

[0001] This invention relates to the field of control technology, and in particular to a method and device for controlling the electromechanical braking basic braking BBF. Background Technology

[0002] Electromechanical braking, as a core actuator in intelligent driving and drive-by-wire chassis, is widely used in advanced autonomous vehicles. Related technologies utilize the coordinated operation of pedal signal acquisition, braking intent calculation, braking force distribution, and wheel-end closed-loop control to construct a basic braking function system. Specifically, this system covers the entire process from driver braking intent recognition to wheel-end braking torque output, including key aspects such as redundant signal acquisition, parallel calculation by dual controllers, and independent closed-loop control of all four wheels.

[0003] However, existing basic braking control methods directly adopt single or dual-path pedal signal acquisition and a centralized control architecture, without constructing a multi-level redundant cross-verification network and a wheel-end local autonomous arbitration mechanism. This may lead to brake failure due to a single-point signal failure, or complete loss of braking capability after bus interruption, thereby affecting the vehicle's driving safety and functional safety level compliance under extreme conditions. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] Therefore, the first objective of this invention is to propose a method for controlling the electromechanical braking basic braking BBF.

[0006] Another objective of this invention is to provide an electromechanical braking basic braking BBF control device.

[0007] The third objective of this invention is to provide a computer device.

[0008] The fourth objective of this invention is to provide a non-transitory computer-readable storage medium.

[0009] To achieve the above objectives, a first aspect of the present invention provides a basic electromechanical braking (BBF) control method, comprising: S10, synchronously acquire multiple independent pedal signals, perform validity screening and consistency cross-checking on the pedal signals, and dynamically arbitrate and output a reliable braking intention value based on the number of remaining valid signals; S20, the target braking torque is calculated independently and in parallel by two controllers, the calculation results are filtered and limited, and the calculation results of the two controllers are cross-compared to output a consistent target braking torque; S30 distributes the target braking torque to the wheel end control unit of each wheel according to the vehicle braking condition. Each wheel end control unit corrects the braking torque in real time through closed-loop control based on local feedback signals, and autonomously switches to local autonomous mode to maintain braking in the event of a bus failure. S40 diagnoses system fault levels in real time, executes corresponding degradation control strategies based on fault levels, and independently triggers blind braking with fixed deceleration by hardware circuitry when all digital signals and communication fail.

[0010] In one embodiment of the present invention, S10 includes: Simultaneously acquire four independent SENT pedal signals at a frequency of 1kHz, complete full-channel data sampling every 1ms, and simultaneously acquire signal voltage, waveform and transmission delay parameters. Valid signals are selected based on valid signal determination criteria, and faulty channels that are out of range, have waveform distortion, or have transmission timeouts are eliminated. The valid signal determination criteria are as follows: ,in Let i be the value of the i-th pedal signal. The effective lower limit threshold of the signal. The effective upper limit threshold of the signal; Perform cross-validation of four signals to ensure consistency. Calculate the deviation between the mean of the valid signals and the deviation of each individual signal. Remove abnormal signals whose deviation exceeds a threshold. The signal consistency verification condition is as follows: ,in The effective signal mean, This is the maximum allowable deviation threshold for the signal; Based on the number of remaining valid signals, a reliable pedal braking intention value is calculated and output using a dynamic arbitration formula. When all four signals are valid, When a single signal fails, When dual-channel signals fail, ,in and These are the remaining two valid signal values.

[0011] In one embodiment of the present invention, it further includes: Based on the formula for calculating the mean of effective signals Calculate the mean of the current valid signals, where n is the number of current valid signals, and n can be 2, 3 or 4; The effective signal value of each channel is compared with the mean value. If the absolute value of the deviation exceeds the maximum allowable deviation threshold of the signal... If the signal is abnormal, it will be rejected.

[0012] In one embodiment of the present invention, S20 includes: The MDC main control unit and the VIU redundant control unit operate independently in parallel, based on reliable braking intention, real-time vehicle speed, wheel speed, and vehicle attitude signals, and using the basic target torque calculation formula. Solve for the initial target braking torque, where This is the proportional coefficient for the pedal opening torque. This is the dynamic correction coefficient for vehicle speed. This represents the deviation between the real-time vehicle speed and the target vehicle speed. A second-order Kalman filter algorithm is used to smooth the initial target braking torque. The filtered torque is subjected to upper and lower limits and a rate of change limit to restrict the maximum step change of torque to no more than 50 N·m / 10 ms. The torque calculation results of the two controllers are cross-compared. If the difference is within the safety threshold, the average value is output. If the difference exceeds the limit, the calculation result of the normal controller is locked.

[0013] In one embodiment of the present invention, it further includes: Cutting formula based on torque limit:

[0014] The filtered torque is trimmed, where The minimum safe braking torque for a single wheel, This is the maximum permissible braking torque for a single wheel; The rate of change of the torque after trimming is limited to ensure smooth torque output without impact.

[0015] In one embodiment of the present invention, S30 includes: Based on the vehicle braking conditions, the initial distribution of braking force to the four wheels is completed according to the braking efficiency coefficients of the front and rear wheels. The braking conditions include conventional braking, emergency braking, and fault braking. Each wheel-end control unit collects wheel-end braking torque and wheel speed feedback signals in real time, and corrects the braking torque in real time using an incremental PID closed-loop algorithm. The adjustment formula for the incremental PID closed loop is as follows: The single-wheel output braking torque is ,in For torque deviation, Real-time acquisition and feedback of braking torque at the wheel end; The system dynamically monitors wheel slip ratio and finely adjusts the braking torque of a single wheel in real time when the slip ratio exceeds the threshold; under normal operating conditions, the torque of all four wheels is output in a balanced manner.

[0016] In one embodiment of the present invention, S40 includes: A four-level fault diagnosis system is established, where level 1 faults are single pedal signal failures, level 2 faults are single CAN bus or single power supply failures, level 3 faults are single wheel-end control unit failures, and level 4 faults are all pedal signals or dual controller failures. When a Level 1 or Level 2 fault occurs, the system does not experience performance degradation and automatically switches to redundant channels for seamless fault-tolerant operation. When a level 3 fault occurs, the three-wheel brake reconfiguration mode is triggered, and the torque distribution is adjusted according to the fault classification and degradation formula. The remaining three-wheel braking force is redistributed, among which The total target braking torque of the vehicle, The braking efficiency coefficients for each wheel are 0.6 for the front wheels and 0.4 for the rear wheels, where n is the number of wheels currently operating normally. When a Level 4 fault occurs, the normal braking mode is exited, and the hard-wired backup braking logic is triggered.

[0017] To achieve the above objectives, a second aspect of the present invention provides an electromechanical braking basic braking BBF control device, comprising: The pedal signal arbitration module is used to synchronously acquire multiple independent pedal signals, perform validity screening and consistency cross-checking on the pedal signals, and dynamically arbitrate and output a reliable braking intention value based on the number of remaining valid signals. The dual-controller torque calculation module is used to calculate the target braking torque in parallel and independently by two controllers, filter and limit the calculation results, and output a consistent target braking torque after cross-comparing the calculation results of the two controllers. The wheel-end torque distribution autonomous control module is used to distribute the target braking torque to the wheel-end control units of each wheel according to the vehicle braking conditions. Each wheel-end control unit corrects the braking torque in real time through closed-loop control based on local feedback signals, and autonomously switches to local autonomous mode to maintain braking in the event of a bus failure. The graded fault degradation braking module is used to diagnose the system fault level in real time, execute the corresponding degradation control strategy according to the fault level, and independently trigger blind braking with fixed deceleration by hardware circuit when all digital signals and communication fail.

[0018] The present invention provides an electromechanical braking basic braking BBF control method and device, which can realize multi-level redundant cross-checking and wheel-end local autonomous control, improve the fault tolerance and extreme condition safety of the braking system, and meet the ASIL-D functional safety level requirements.

[0019] To achieve the above objectives, a third aspect of this application provides a computer device, including a processor and a memory; wherein the processor runs a program corresponding to the executable program code by reading executable program code stored in the memory, for implementing the method described in the first aspect embodiment.

[0020] To achieve the above objectives, a fourth aspect of this application provides a non-transitory computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the method described in the first aspect.

[0021] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0022] Figure 1 This is a flowchart of an electromechanical braking basic braking BBF control method according to an embodiment of the present invention; Figure 2 This is a structural diagram of an electromechanical braking basic braking BBF control device according to an embodiment of the present invention; Figure 3 It is a computer device according to an embodiment of the present invention. Detailed Implementation

[0023] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0024] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0025] The following description, with reference to the accompanying drawings, describes an electromechanical braking basic braking BBF control method and device proposed according to an embodiment of the present invention.

[0026] Figure 1 This is a flowchart of a basic electromechanical braking (BBF) control method according to an embodiment of the present invention, as shown below. Figure 1 As shown, it includes: S10, synchronously acquire multiple independent pedal signals, perform validity screening and consistency cross-checking on the pedal signals, and dynamically arbitrate and output a reliable braking intention value based on the number of remaining valid signals; S20, the target braking torque is calculated independently and in parallel by two controllers, the calculation results are filtered and limited, and the calculation results of the two controllers are cross-compared to output a consistent target braking torque; S30 distributes the target braking torque to the wheel end control unit of each wheel according to the vehicle braking condition. Each wheel end control unit corrects the braking torque in real time through closed-loop control based on local feedback signals, and autonomously switches to local autonomous mode to maintain braking in the event of a bus failure. S40 diagnoses system fault levels in real time, executes corresponding degradation control strategies based on fault levels, and independently triggers blind braking with fixed deceleration by hardware circuitry when all digital signals and communication fail.

[0027] This invention constructs four improved core network models: a multi-level redundant cross-validation network, a hierarchical fault degradation network, a wheel-end local closed-loop arbitration network, and a hard-wired fallback trigger network. It is equipped with complete calculation formulas and step-by-step processing procedures to achieve ASIL-D level safety braking under a pure EMB non-hydraulic backup architecture.

[0028] In one embodiment of the present invention, an electromechanical braking basic braking BBF control system is proposed, comprising: an improved distributed network structure with dual-control redundancy, four-wheel autonomy, quadruple signal acquisition, and triple safety backup, specifically including: an MDC main control unit, a VIU redundant control unit, four-wheel WCU wheel-end control units, a four-channel PTS pedal SENT redundant acquisition unit, a BLS brake light hard-wired direct-connection unit, a dual CAN redundant communication unit, and a dual-channel isolated power supply unit. Each unit adopts a hierarchical heterogeneous network layout, which differs from the traditional single centralized architecture, and possesses independent computing, cross-validation, and autonomous fault reconstruction capabilities.

[0029] Furthermore, the improved network structure and functional principles of each unit, using the MDC main control unit + VIU redundant control unit (dual-control parallel redundant network), abandon the traditional simple master-slave backup mode. It adopts a dual-controller parallel independent calculation + real-time data cross-comparison network structure. Both the MDC and VIU have built-in complete braking intent calculation, torque distribution, and fault diagnosis algorithms. The two controllers complete data interaction verification every 10μs, forming a closed-loop comparison network, rather than a single master operation and standby standby. Network workflow: The MDC collects global vehicle status signals to complete the main braking demand calculation. The VIU synchronously and independently collects four-channel pedal signals, vehicle speed, and wheel speed signals to complete redundant calculation. The two controllers exchange calculation results in real time through a dual CAN network. If the difference is within the safety threshold, an average value command is output; if the difference exceeds the limit, a single controller fault is determined, the normal controller command is locked, and the faulty calculation result is discarded.

[0030] Furthermore, the four-wheel WCU wheel-end control unit (wheel-end local autonomous arbitration network) differs from traditional WCUs which only execute commands. This invention establishes a wheel-end local primary / backup command selection + torque closed-loop self-correction network. Each wheel corresponds to an independent WCU, and each WCU has a built-in local arbitration module, PID closed-loop control module, and fault self-diagnosis and reconfiguration module, forming a distributed independent control sub-network. It can autonomously complete braking control without relying on real-time commands from the central controller. Network workflow: Each WCU simultaneously receives the MDC main command and VIU redundant commands, performs command validity verification and priority determination locally, and automatically disconnects from central control in case of bus failure. Based on local wheel speed and torque feedback signals, it autonomously outputs braking torque, achieving wheel-end autonomy.

[0031] Furthermore, the four-channel PTS pedal SENT redundant acquisition unit (four-channel cross-validation arbitration network) differs from the traditional 1-2 channel signal acquisition. It builds a network for synchronous acquisition of four heterogeneous SENT signals, consistency cross-validation, and priority dynamic arbitration. The four sensors use different power supply circuits and different transmission lines to avoid common-mode faults and have the ability to automatically eliminate single-channel and dual-channel faults and reconstruct data.

[0032] Furthermore, the BLS brake light hard-wired direct-connect unit (pure hardware fallback trigger network) abandons the traditional software trigger fallback mode and adopts an independent hardware circuit conduction network, which is completely isolated from the CAN bus and controller software. It does not rely on any digital signals. When all four pedal signals fail, the dual controllers fail, or the bus is completely interrupted, the hardware circuit will automatically trigger and output a fixed braking command to achieve blind braking fallback.

[0033] Furthermore, the dual CAN redundant communication unit + dual isolated power supply unit adopts a dual-channel independent isolated communication and independent power supply network. The two CAN buses and two power supply circuits are completely physically isolated, with no shared lines or chips, avoiding overall failure due to single point of failure, supporting seamless switching for single channel failure, and zero functional degradation.

[0034] In one embodiment of the present invention, the system network operation formula and the four-way pedal signal consistency verification formula are given, assuming the real-time acquisition signal values ​​of the four PTS pedals are: The effective lower limit threshold of the signal is The effective upper limit threshold of the signal is The maximum allowable deviation threshold for the signal is ; Single-channel signal valid determination condition: Signal consistency verification conditions: The formula for calculating the mean of the effective signal is as follows: , The number of currently valid signal channels (n=2, 3, 4).

[0035] Furthermore, the arbitration formula for the reliability value of pedal braking intention: Normal four-way effective: Single signal failure: The faulty channel is automatically removed, and the average of the remaining three valid signals is output, formula: Dual-path failure: Weighted average output of the remaining two paths. .

[0036] Furthermore, the formula for calculating the target braking pressure / torque is as follows: The formula for calculating the basic target torque is as follows: ;in: This is the proportional coefficient for the pedal opening torque. This is the dynamic correction coefficient for vehicle speed. The deviation between real-time vehicle speed and target vehicle speed; torque limit trimming formula: ,in The minimum safe braking torque for a single wheel, This is the maximum permissible braking torque for a single wheel.

[0037] Furthermore, the wheel-end closed-loop PID control formula is as follows: Wheel-end incremental PID closed-loop adjustment formula: Single-wheel output braking torque: ,in For torque deviation, Real-time acquisition and feedback of braking torque at the wheel end.

[0038] Furthermore, the fault classification and degradation torque distribution formula is as follows: The remaining wheel torque reconstruction distribution formula after a single wheel WCU failure is as follows: ;in: The total target braking torque of the vehicle, The braking efficiency coefficients for each wheel are (0.6 for the front wheels and 0.4 for the rear wheels). This represents the number of wheel ends currently in normal operation.

[0039] Furthermore, the formula for limiting the torque of the double-pedal protection is as follows: The condition for triggering double-pedal protection is: (Throttle opening exceeds threshold, brakes are effective, vehicle speed exceeds threshold); Double-clutch protection torque limit formula: By dynamically reducing the basic braking torque, the conflict between power and braking is eliminated.

[0040] Furthermore, the BLS hard-wired blind braking deceleration formula: Fixed safety deceleration for hardware blind braking in full signal failure: (Meets the minimum braking deceleration requirements of national standard GB7258), formula for calculating blind braking torque: ;in: For vehicle curb weight The dynamic rolling radius of the wheel.

[0041] This invention proposes another electromechanical braking basic braking BBF control method. Based on the improved network model described above, it adopts a hierarchical and step-by-step processing logic, comprising seven core steps. Each step has independent data processing, verification, and fault tolerance mechanisms, and is fully compatible with a pure EMB architecture without hydraulic backup. The specific steps are as follows: S1: Acquisition, cross-validation, and priority arbitration of four-channel PTS pedal signals to output a reliable braking intention: Four independent SENT pedal signals are simultaneously acquired at a frequency of 1kHz, with full-channel data sampling completed every 1ms. Signal voltage, waveform, and transmission delay parameters are acquired synchronously. Based on the above signal validity determination formula, valid signals are filtered, and faulty channels with over-range, waveform distortion, or transmission timeout are eliminated. Cross-validation of the consistency of the four signals is performed, calculating the deviation between the average of the valid signals and the single-channel signal, and eliminating abnormal signals with deviations exceeding the threshold. Based on the number of remaining valid signals, a reliable pedal braking intention value is calculated and output using a dynamic arbitration formula. There is no signal interruption or numerical change when single or dual channels fail.

[0042] S2: Braking demand calculation, filtering, and limit processing, outputting the target braking torque for all four wheels: The MDC and VIU dual controllers operate in parallel and independently, calculating the initial target braking torque based on reliable braking intent, real-time vehicle speed, wheel speed, and vehicle attitude signals using the basic torque formula; a second-order Kalman filter algorithm is used to smooth the initial torque, filtering out torque fluctuations caused by electromagnetic interference and pedal vibration. The filtering formula is as follows: State prediction equation: ; Covariance prediction equation: ; State update equation: ; Furthermore, the filtered torque is subjected to upper and lower limits and a rate of change limit to restrict the maximum step change of torque to ≤50 N·m / 10 ms to avoid braking shock; the torque calculation results of the dual controllers are cross-compared, and the difference is averaged within the threshold and output; if the difference exceeds the limit, the result of the normal controller is locked.

[0043] S3: Dynamic Distribution and Closed-Loop Control of Four-Wheel Braking Force: Based on the vehicle's braking conditions (normal braking, emergency braking, and fault braking), and using the braking efficiency coefficients of the front and rear wheels, the initial distribution of four-wheel braking force is completed. Each wheel's WCU unit collects wheel-end braking torque and wheel speed feedback signals in real time, and corrects the braking torque in real time through an incremental PID closed-loop algorithm to eliminate steady-state errors. The wheel slip ratio is dynamically monitored, and when the slip ratio exceeds the threshold, the braking torque of a single wheel is finely adjusted in real time to prevent wheel lock-up and vehicle sideslip. Under normal operating conditions, the torque of the four wheels is output in a balanced manner to ensure braking smoothness and vehicle stability.

[0044] S4: Dual-pedal protection, overspeed limit, and silent safety status management: Dual-pedal protection monitoring: Real-time acquisition of throttle opening and brake pedal signals. When the vehicle speed > 30km / h, throttle opening > 20%, and braking is effective, the dual-pedal protection mechanism is triggered. The maximum braking torque is constrained by the torque limit formula, and an instrument alarm signal is output simultaneously to prevent power and braking conflicts; Overspeed limit management: When the vehicle speed exceeds the set threshold, the braking response priority is forcibly increased, the torque output rate is increased, and the braking distance is shortened; Silent safety control: When the vehicle is stationary and there is no braking demand, the system enters a silent lock state, closes invalid calculation channels, and locks the braking output to zero to prevent malfunctions from triggering braking.

[0045] S5: Real-time system fault diagnosis and graded degradation control: Establish a four-level fault diagnosis system: Level 1 fault (single pedal signal failure), Level 2 fault (single CAN / single power supply failure), Level 3 fault (single wheel WCU failure), Level 4 fault (full pedal signal / dual controller failure); Level 1 and Level 2 faults: No system performance degradation, automatic switching of redundant channels, imperceptible fault-tolerant operation; Level 3 fault: Triggering the three-wheel braking reconfiguration mode, redistributing the remaining three-wheel braking force through the fault torque distribution formula to ensure that the vehicle can brake smoothly and steer normally, without sideslip or lock-up; Level 4 fault: Exiting the normal braking mode and triggering the hard-wired bottom-line braking logic.

[0046] S6: Wheel-end primary and backup command selection and fault reconstruction: Each WCU receives the MDC primary command and VIU backup command in real time and in parallel, and performs local command validity verification, timing verification, and value verification; under normal operating conditions, the primary command is executed first, and the consistency of the backup command is monitored synchronously; when the primary command times out, is abnormal, or the bus is interrupted, the WCU autonomously switches to the backup command for execution, with a switching delay of ≤1ms; when both buses fail completely, the WCU starts the local autonomous mode, autonomously outputs a stable braking torque based on wheel speed feedback, and maintains the basic braking function.

[0047] S7: When all signals fail, fixed deceleration blind braking is triggered by BLS hardwire as a fallback: The system monitors the status of four pedal signals, dual controllers, and dual CAN buses in real time. When all digital signals, communication, and control units fail completely, the software system automatically fails, and the hardware BLS unit independently conducts; the BLS hardwire unit directly outputs a fixed braking command, outputting a constant braking torque based on the safe deceleration formula; the vehicle decelerates smoothly to a stop at a stable deceleration of 2.5m / s², and automatically releases the brake lock after stopping to avoid prolonged dragging; the fault is stored in the system log, supporting subsequent fault review and OTA diagnosis.

[0048] The embodiments of this invention also have the following technical effects: A four-way pedal redundant arbitration network: Employing four-way SENT signal cross-verification and dynamic arbitration, it possesses extremely strong anti-electromagnetic interference and anti-line fault capabilities. Single-way or dual-way signal failure does not affect braking output, significantly improving braking continuity and stability, and completely solving the problem of single-point signal failure in traditional solutions; A refined hierarchical fault degradation mechanism: Dedicated fault-tolerant strategies are designed for different levels of faults in signal, communication, power supply, and execution. Any single-point fault does not result in loss of braking capability or a sudden drop in braking performance, fully meeting the requirements of national standard continuous braking regulations; A wheel-end local autonomous arbitration network: Abandoning the traditional central unidirectional control mode, the wheel end possesses independent command arbitration, closed-loop control, and fault reconstruction capabilities. Bus faults and central controller failures are addressed. It can still perform effective braking even in abnormal situations, with braking response speed improved by more than 30%, and safety under extreme conditions significantly improved; Triple safety backup mechanism: integrating dual-step conflict protection, silent safety to prevent accidental triggering, and BLS hard-wired blind braking in complete failure, a triple backup strategy, fully covering normal abnormal and extreme failure conditions, with no safety blind spots; Meets the highest functional safety level ASIL-D: pure EMB independent architecture without hydraulic backup, eliminating reliance on traditional hydraulic systems, high integration, fast response speed, and strong reliability, and can be directly installed in high-end intelligent driving mass-produced vehicles; Excellent braking smoothness: through second-order Kalman filtering, torque gradient limiting, and PID closed-loop self-correction algorithm, it achieves smooth transition of braking force, with no impact, no shaking, and no jerking during the braking process, greatly improving the driving experience.

[0049] To achieve the above embodiments, such as Figure 2 As shown, this embodiment also provides an electromechanical braking basic braking BBF control device 10, including: The pedal signal arbitration module 100 is used to synchronously acquire multiple independent pedal signals, perform validity screening and consistency cross-checking on the pedal signals, and dynamically arbitrate and output a reliable braking intention value based on the number of remaining valid signals. The dual-controller torque calculation module 200 is used to calculate the target braking torque in parallel and independently by the two controllers, filter and limit the calculation results, and output a consistent target braking torque after cross-comparing the calculation results of the two controllers. The wheel-end torque distribution autonomous control module 300 is used to distribute the target braking torque to the wheel-end control units of each wheel according to the vehicle braking conditions. Each wheel-end control unit corrects the braking torque in real time through closed-loop control based on local feedback signals, and autonomously switches to local autonomous mode to maintain braking in the event of a bus failure. The graded fault degrading braking module 400 is used to diagnose the system fault level in real time, execute the corresponding degrading control strategy according to the fault level, and independently trigger blind braking with fixed deceleration by hardware circuit when all digital signals and communication fail.

[0050] An embodiment of the present invention provides an electromechanical braking basic braking BBF control device, which can realize multi-level redundant cross-checking and wheel-end local autonomous control, improve the fault tolerance and extreme condition safety of the braking system, and meet the ASIL-D functional safety level requirements.

[0051] To implement the methods of the above embodiments, the present invention also provides a computer device, such as... Figure 3 As shown, the computer device 600 includes a memory 601 and a processor 602; wherein, the processor 602 reads executable program code stored in the memory 601 to run a program corresponding to the executable program code, so as to implement the various steps of the method described above.

[0052] To implement the above embodiments, this application also proposes a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the method described in the foregoing embodiments.

[0053] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0054] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

Claims

1. A method for controlling the basic braking BBF (Battery Brake) of an electromechanical braking system, characterized in that, include: S10, synchronously acquire multiple independent pedal signals, perform validity screening and consistency cross-checking on the pedal signals, and dynamically arbitrate and output a reliable braking intention value based on the number of remaining valid signals; S20, the target braking torque is calculated independently and in parallel by two controllers, the calculation results are filtered and limited, and the calculation results of the two controllers are cross-compared to output a consistent target braking torque; S30 distributes the target braking torque to the wheel end control unit of each wheel according to the vehicle braking condition. Each wheel end control unit corrects the braking torque in real time through closed-loop control based on local feedback signals, and autonomously switches to local autonomous mode to maintain braking in the event of a bus failure. S40 diagnoses system fault levels in real time, executes corresponding degradation control strategies based on fault levels, and independently triggers blind braking with fixed deceleration by hardware circuitry when all digital signals and communication fail.

2. The method as described in claim 1, characterized in that, S10 includes: Simultaneously acquire four independent SENT pedal signals at a frequency of 1kHz, complete full-channel data sampling every 1ms, and simultaneously acquire signal voltage, waveform and transmission delay parameters. Valid signals are selected based on valid signal determination criteria, and faulty channels that are out of range, have waveform distortion, or have transmission timeouts are eliminated. The valid signal determination criteria are as follows: ,in Let i be the value of the i-th pedal signal. The effective lower limit threshold of the signal. The effective upper limit threshold of the signal; Perform cross-validation of four signals to ensure consistency. Calculate the deviation between the mean of the valid signals and the deviation of each individual signal. Remove abnormal signals whose deviation exceeds a threshold. The signal consistency verification condition is as follows: ,in The effective signal mean, This is the maximum allowable deviation threshold for the signal; Based on the number of remaining valid signals, a reliable pedal braking intention value is calculated and output using a dynamic arbitration formula. When all four signals are valid, When a single signal fails, When dual-channel signals fail, ,in and These are the remaining two valid signal values.

3. The method as described in claim 2, characterized in that, The method further includes: Based on the formula for calculating the mean of effective signals Calculate the mean of the current valid signals, where n is the number of current valid signals, and n can be 2, 3 or 4; The effective signal value of each channel is compared with the mean value. If the absolute value of the deviation exceeds the maximum allowable deviation threshold of the signal... If the signal is abnormal, it will be rejected.

4. The method as described in claim 1, characterized in that, S20 includes: The MDC main control unit and the VIU redundant control unit operate independently in parallel, based on reliable braking intention, real-time vehicle speed, wheel speed, and vehicle attitude signals, and using the basic target torque calculation formula. Solve for the initial target braking torque, where This is the proportional coefficient for the pedal opening torque. This is the dynamic correction coefficient for vehicle speed. This represents the deviation between the real-time vehicle speed and the target vehicle speed. A second-order Kalman filter algorithm is used to smooth the initial target braking torque. The filtered torque is subjected to upper and lower limits and a rate of change limit to restrict the maximum step change of torque to no more than 50 N·m / 10 ms. The torque calculation results of the two controllers are cross-compared. If the difference is within the safety threshold, the average value is output. If the difference exceeds the limit, the calculation result of the normal controller is locked.

5. The method as described in claim 4, characterized in that, The method further includes: Cutting formula based on torque limit: The filtered torque is trimmed, where The minimum safe braking torque for a single wheel, This is the maximum permissible braking torque for a single wheel; The rate of change of the torque after trimming is limited to ensure smooth torque output without impact.

6. The method as described in claim 1, characterized in that, S30 includes: Based on the vehicle braking conditions, the initial distribution of braking force to the four wheels is completed according to the braking efficiency coefficients of the front and rear wheels. The braking conditions include conventional braking, emergency braking, and fault braking. Each wheel-end control unit collects wheel-end braking torque and wheel speed feedback signals in real time, and corrects the braking torque in real time using an incremental PID closed-loop algorithm. The adjustment formula for the incremental PID closed loop is as follows: The single-wheel output braking torque is ,in For torque deviation, Real-time acquisition and feedback of braking torque at the wheel end; The system dynamically monitors wheel slip ratio and finely adjusts the braking torque of a single wheel in real time when the slip ratio exceeds the threshold; under normal operating conditions, the torque of all four wheels is output in a balanced manner.

7. The method as described in claim 1, characterized in that, S40 includes: A four-level fault diagnosis system is established, where level 1 faults are single pedal signal failures, level 2 faults are single CAN bus or single power supply failures, level 3 faults are single wheel-end control unit failures, and level 4 faults are all pedal signals or dual controller failures. When a Level 1 or Level 2 fault occurs, the system does not experience performance degradation and automatically switches to redundant channels for seamless fault-tolerant operation. When a level 3 fault occurs, the three-wheel brake reconfiguration mode is triggered, and the torque distribution is adjusted according to the fault classification and degradation formula. The remaining three-wheel braking force is redistributed, among which The total target braking torque of the vehicle, The braking efficiency coefficients for each wheel are 0.6 for the front wheels and 0.4 for the rear wheels, where n is the number of wheels currently operating normally. When a Level 4 fault occurs, the normal braking mode is exited, and the hard-wired backup braking logic is triggered.

8. A basic electromechanical braking (BBF) control device, characterized in that, include: The pedal signal arbitration module is used to synchronously acquire multiple independent pedal signals, perform validity screening and consistency cross-checking on the pedal signals, and dynamically arbitrate and output a reliable braking intention value based on the number of remaining valid signals. The dual-controller torque calculation module is used to calculate the target braking torque in parallel and independently by two controllers, filter and limit the calculation results, and output a consistent target braking torque after cross-comparing the calculation results of the two controllers. The wheel-end torque distribution autonomous control module is used to distribute the target braking torque to the wheel-end control units of each wheel according to the vehicle braking conditions. Each wheel-end control unit corrects the braking torque in real time through closed-loop control based on local feedback signals, and autonomously switches to local autonomous mode to maintain braking in the event of a bus failure. The graded fault degradation braking module is used to diagnose the system fault level in real time, execute the corresponding degradation control strategy according to the fault level, and independently trigger blind braking with fixed deceleration by hardware circuit when all digital signals and communication fail.

9. A computer device, characterized in that, Including processor and memory; The processor reads executable program code stored in the memory to run a program corresponding to the executable program code, so as to implement the method as described in any one of claims 1-7.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1-7.

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