An Electronic Pre-Brake (EBP) Pedal Release Pre-judgment and Pre-fill Control Method and System

Abstract

This application discloses an electronic pre-braking (EBP) pedal release prediction and pre-filling control method and system, relating to the fields of automotive electromechanical braking (EMB), active safety prediction, electronic pre-braking (EBP), and brake-by-wire clearance pre-filling technology. It collects information on accelerator pedal opening, accelerator pedal release rate, vehicle speed, wheel speed, brake pedal status, and vehicle driving conditions. Based on the accelerator pedal release rate and vehicle speed, it sets multi-level threshold intervals to determine the driver's potential emergency braking intention. This application achieves multi-dimensional intention prediction based on accelerator release changes and vehicle speed information, and combines it with electromechanical brake clearance pre-filling control to enable the braking system to enter a ready-to-respond state in advance, improving the vehicle's active safety capabilities. Through multi-condition adaptive adjustment and functional constraint and redundancy control mechanisms, it ensures a smooth and reliable pre-filling process and maintains functional continuity under abnormal conditions, making it suitable for applications using brake-by-wire systems without hydraulic pressure.

Description

Technical Field

[0001] This application relates to the fields of automotive electromechanical braking (EMB), active safety prediction, electronic pre-braking (EBP), and brake-by-wire clearance pre-filling technology, specifically to an electronic pre-braking (EBP) pedal release prediction and pre-filling control method and system. Background Technology

[0002] With the development of active safety technologies in automobiles, Electronic Pre-Braking (EBP) technology is increasingly being applied to the field of vehicle emergency braking assistance. It primarily shortens braking response time and improves driving safety by establishing braking force or eliminating brake system clearances before the driver depresses the brake pedal. Existing pre-braking technologies are typically triggered based on vehicle state parameters (such as vehicle speed, distance to the vehicle ahead, or collision risk assessment), with some schemes triggering pre-braking by setting a vehicle speed threshold or based on a forward collision warning system. However, existing technologies are mostly concentrated in traditional hydraulic braking systems, and their control strategies often rely on a single trigger condition, lacking in-depth recognition of driver actions, such as not fully utilizing key features reflecting driving intentions, such as the rate of accelerator pedal release. Furthermore, in purely electro-mechanical braking (EMB) systems, due to the mechanical backlash in their braking actuators, existing pre-braking technologies have not yet designed reasonable pre-fill control strategies to address this structural characteristic. In addition, existing systems lack multi-condition joint judgment and adaptive adjustment mechanisms in complex driving environments (such as high-speed driving, low-speed following, slopes or slippery roads), and also rarely consider the coordinated control relationship with the vehicle's anti-lock braking system (ABS), electronic stability control system (ESC) and adaptive cruise control system (ACC).

[0003] Although existing pre-braking technologies can improve braking response performance to some extent, they still have many shortcomings, specifically: First, most existing solutions rely on a single parameter (such as vehicle speed or distance) as the triggering basis, lacking the ability to accurately identify the driver's potential emergency braking intentions. This easily leads to false triggering or missed triggering, affecting system reliability. Second, for pure EMB braking systems, existing technologies have failed to design reasonable pre-fill torque and stroke control strategies based on their mechanical clearance characteristics. This results in either an inability to effectively eliminate braking play and limited improvement in response speed, or the generation of unnecessary braking drag, affecting driving comfort. Furthermore, existing technologies generally lack adaptive triggering mechanisms for different operating conditions (such as high speed and low speed, following other vehicles and free driving, flat roads and slopes), leading to poor system applicability in complex environments. In terms of safety, existing solutions typically lack comprehensive fault diagnosis and shielding mechanisms. Pre-braking may still be triggered when the pedal signal or wheel speed signal is abnormal, posing a potential safety hazard. Simultaneously, the lack of controller redundancy means that the pre-braking function will be completely lost if the main control unit fails. In addition, existing systems have not established priority interlocking mechanisms with chassis active safety functions such as ABS, ESC, and ACC, which can easily lead to control conflicts when functions are activated simultaneously, thus affecting vehicle stability and driving safety.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this application is to provide an electronic pre-braking (EBP) pedal release prediction and pre-filling control method and system to solve the problems in the background art mentioned above.

[0006] To achieve the above objectives, this application provides the following technical solution: an electronic pre-braking (EBP) pedal release prediction and pre-filling control method, comprising the following steps: Collect information on accelerator pedal opening, accelerator pedal release rate, vehicle speed, wheel speed, brake pedal status, and vehicle operating conditions. Based on the rate of change in accelerator pedal release and vehicle speed, multiple threshold ranges are set to determine the driver's potential emergency braking intention. When the judgment result meets any of the following conditions: high-speed rapid throttle release, following vehicle driving, or sudden pedal release, the electronic pre-braking (EBP) pre-fill state is entered. Based on the pre-fill state of the electronic pre-braking (EBP), the wheel control unit drives the electromechanical brake actuator to perform small torque clearance pre-filling to eliminate mechanical clearance. During the pre-filling process of the small torque gap, the brake pedal status is monitored. When the brake pedal is detected to be pressed, a smooth transition from the pre-filling state to the normal braking state is performed. When the brake pedal is not pressed and the accelerator pedal is restored or the preset time limit is reached, the electronic pre-braking (EBP) pre-filling state is exited. Control constraints are implemented based on the status of vehicle active safety functions and signal validity. When the anti-lock braking system, vehicle stability control, or adaptive cruise control is active, the electronic pre-braking (EBP) function is prohibited from being triggered. When the accelerator pedal signal or wheel speed signal is abnormal, the electronic pre-braking (EBP) function is disabled. When the main controller fails, the system switches to the redundant controller to perform prediction and pre-filling control.

[0007] Preferably, the rate of change of accelerator pedal release is obtained by time-series sampling and differential calculation of the accelerator pedal opening signal, and the influence of high-frequency noise is eliminated by filtering algorithm. At the same time, the change amplitude within a preset time window is divided into multiple level intervals, and different level intervals correspond to different emergency braking intention judgment weights, thereby achieving refined recognition of the trend of driving behavior changes.

[0008] Preferably, the multi-level threshold intervals are mapped by dividing the vehicle speed intervals. Different vehicle speed intervals correspond to different threshold ranges for the rate of change of accelerator pedal release. At the same time, the longitudinal acceleration change trend is introduced to participate in the judgment. When the rate of change of accelerator pedal release is consistent with the direction of deceleration change, the trigger priority is increased, thereby improving the reliability of intent recognition.

[0009] Preferably, the following driving condition is jointly identified by the periodic characteristics of wheel speed fluctuation and the amplitude of vehicle speed change. When the wheel speed change is periodic and the vehicle speed fluctuation range is within the preset range, it is determined to be a following state, and the pre-filled trigger conditions and duration parameters are adjusted in this state.

[0010] Preferably, the small torque gap pre-filling is achieved by controlling the output current curve of the drive motor of the electromechanical braking actuator. The current curve adopts a piecewise function form, and the current growth rate is limited when approaching the critical position of mechanical gap elimination to avoid entering the actual braking force output range. The inflection point of current change is used to determine the near contact state of the friction pair.

[0011] Preferably, the gap elimination state is determined by combining the trend of the drive motor current change with the displacement estimation model. When the current shows a stable upward trend and the displacement change tends to slow down, it is determined that the gap critical position has been reached, and the pre-fill state is maintained to wait for braking trigger.

[0012] Preferably, the pre-fill exit control adopts a phased release strategy, including a maintenance phase and a retraction phase. During the maintenance phase, the drive motor maintains a low current output, and during the retraction phase, the current is gradually reduced to zero, thereby avoiding mechanical shock and vehicle response fluctuations caused by rapid separation of the brake friction pair.

[0013] Preferably, a time hysteresis control mechanism is introduced into the pre-filling trigger and exit process. By setting the minimum trigger duration and the minimum exit delay time, frequent switching in the critical state is prevented. At the same time, the exit judgment condition is set in combination with the accelerator pedal opening recovery range.

[0014] Preferably, the signal validity detection includes range verification, rate of change verification, and multi-signal consistency verification of the accelerator pedal signal, wheel speed signal, and brake pedal signal. When any signal does not meet the preset reasonable range or change pattern, it is marked as an abnormal state and the electronic pre-braking (EBP) is prohibited from being triggered.

[0015] An electronic pre-braking (EBP) pedal release prediction and pre-filling control system includes a pedal speed signal acquisition module, an intent recognition threshold determination module, a working condition triggering pre-braking module, a gap pre-filling execution module, a brake transition exit control module, and a safety constraint redundancy control module. The pedal speed signal acquisition module collects information such as accelerator pedal opening, accelerator pedal release rate, vehicle speed, wheel speed, brake pedal status, and vehicle driving conditions. The intent recognition threshold determination module sets multiple threshold ranges based on the rate of change of accelerator pedal release and vehicle speed to determine the driver's potential emergency braking intent. The working condition trigger pre-braking module enters the electronic pre-braking (EBP) pre-filling state when the judgment result meets any of the following conditions: high-speed rapid throttle release, following vehicle driving, or sudden pedal release. The gap prefilling execution module, based on the electronic pre-braking (EBP) prefilling state, controls the wheel control unit to drive the electromechanical brake actuator to perform small-torque gap prefilling to eliminate mechanical gaps; The brake transition exit control module monitors the brake pedal status during the small torque gap pre-filling process. When the brake pedal is detected to be pressed, a smooth transition from the pre-filling state to the normal braking state is executed. When the brake pedal is not pressed and the accelerator pedal is restored or the preset time limit is reached, the electronic pre-braking (EBP) pre-filling state is exited. The safety constraint redundancy control module performs control constraints based on the vehicle's active safety function status and signal validity status. When the anti-lock braking function, vehicle stability control function, or adaptive cruise control function is active, the electronic pre-braking (EBP) function is prohibited from being triggered. When the accelerator pedal signal or wheel speed signal is abnormal, the electronic pre-braking (EBP) function is disabled. When the main controller fails, the module switches to the redundant controller to perform prediction and pre-filling control.

[0016] The technical effects and advantages provided by this application in the above technical solution are as follows: This application introduces a joint determination mechanism combining accelerator pedal release characteristics and vehicle driving status information, transforming driving behavior recognition from a single-state judgment to a multi-dimensional dynamic analysis. This allows for intention prediction before the driver's actual braking operation. Furthermore, by incorporating gap pre-filling control in the electromechanical brake actuator, the braking system enters a ready-to-respond state in advance, reducing response lag caused by mechanical gaps. This approach maintains stable triggering logic under various vehicle speed conditions, enabling advance response preparation in high-speed scenarios and avoiding unnecessary triggering in low-speed following scenarios. This ensures both control accuracy and operational stability, resulting in enhanced active safety response capabilities for the vehicle across diverse driving environments.

[0017] This application constructs an adaptive control system for multiple operating conditions, introducing a flexible adjustment strategy during pre-fill triggering, maintenance, and exit processes to maintain a continuous transition during braking execution, thereby avoiding interference with the driving experience. Simultaneously, by setting functional constraint logic and fault handling mechanisms, control behavior is limited during the operation of different active safety functions. The operating strategy is automatically adjusted in the event of signal or controller anomalies, and redundant takeover is implemented in the event of control unit failure, ensuring the continuity of the braking pre-response function under complex operating conditions. This overall control approach not only improves system reliability but also adapts to non-hydraulic drive-by-wire chassis structures, providing support for vehicle applications with high-level functional safety requirements. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0019] Figure 1 This is a flowchart of the method in this application.

[0020] Figure 2 This is a schematic diagram of the system modules of this application. Detailed Implementation

[0021] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art.

[0022] like Figure 1 As shown, this application provides an electronic pre-braking (EBP) pedal release prediction and pre-filling control method, including the following steps: Collect information on accelerator pedal opening, accelerator pedal release rate, vehicle speed, wheel speed, brake pedal status, and vehicle operating conditions. Based on the rate of change in accelerator pedal release and vehicle speed, multiple threshold ranges are set to determine the driver's potential emergency braking intention. When the judgment result meets any of the following conditions: high-speed rapid throttle release, following vehicle driving, or sudden pedal release, the electronic pre-braking (EBP) pre-fill state is entered. Based on the pre-fill state of the Electronic Pre-Brake (EBP), the wheel control unit drives the electromechanical brake actuator to perform small torque clearance pre-fill to eliminate mechanical clearance and avoid brake drag. During the pre-filling process of the small torque gap, the brake pedal status is monitored. When the brake pedal is detected to be pressed, a smooth transition from the pre-filling state to the normal braking state is performed. When the brake pedal is not pressed and the accelerator pedal is restored or the preset time limit is reached, the electronic pre-braking (EBP) pre-filling state is exited. Control constraints are implemented based on the status of vehicle active safety functions and signal validity. When the anti-lock braking system, vehicle stability control, or adaptive cruise control is active, the electronic pre-braking (EBP) function is prohibited from being triggered. When the accelerator pedal signal or wheel speed signal is abnormal, the electronic pre-braking (EBP) function is disabled. When the main controller fails, the system switches to the redundant controller to perform prediction and pre-filling control.

[0023] Implementation Method 1: In this implementation method, the vehicle operates in a high-speed driving scenario, and the vehicle control system runs the Electronic Pre-Brake (EBP) pedal release prediction and pre-fill control method in real time. The system first acquires the vehicle's current operating state through multi-source sensor signals, including key parameters such as accelerator pedal opening signal, accelerator pedal opening rate of change signal, vehicle speed signal, wheel speed signal, and brake pedal state signal. Simultaneously, it combines vehicle dynamics information to identify the current driving condition. When the vehicle speed exceeds the lower limit of a pre-calibrated high-speed threshold range, the system identifies the current condition as a high-speed driving condition and activates an intent recognition strategy specific to the high-speed scenario.

[0024] After high-speed condition recognition is completed, the system enters a continuous monitoring phase, sampling the accelerator pedal opening changes at high frequency. The system calculates the accelerator pedal release rate by performing differential operations or filtering on the sampled data. When the accelerator pedal opening decreases rapidly within a preset time window, and the accelerator pedal release rate exceeds a preset threshold range corresponding to high-speed conditions, the system comprehensively judges the driving behavior based on the vehicle's current speed, wheel speed consistency, and longitudinal acceleration trend. This judgment logic not only considers a single rate threshold but can also achieve different levels of emergency intent recognition through multi-level threshold range division. For example, the release rate can be divided into rapid release, medium release, and slow release levels, and cross-judged based on vehicle speed ranges, thereby avoiding false triggers at low speeds and missed triggers at high speeds.

[0025] When the judgment result meets the characteristic conditions of rapid throttle release at high speed, the system identifies the current driving behavior as a potential emergency braking intention and immediately triggers the Electronic Pre-Brake (EBP) pre-fill state. During the activation of this state, the system sends control commands to the electromechanical brake actuator through the wheel control unit, causing the brake actuator to operate according to a preset low-torque control strategy. This low-torque control strategy is calibrated based on the mechanical structural characteristics of the electromechanical brake actuator. Its core is to drive the brake friction pair towards the brake disc without generating significant braking force output, thereby gradually eliminating the brake clearance.

[0026] During execution, the drive motor of the electromechanical braking actuator is controlled according to a preset current or torque control curve, causing the brake friction pads to gradually approach the brake disc, but always remaining near the critical contact area where no effective braking force is generated. This critical area can be determined by the characteristics of motor current changes, displacement estimation models, or force feedback models. For example, when the motor drive current shows a slight increase but does not reach the braking force establishment threshold, it can be considered that the gap elimination position is approaching. In this way, the system can complete the pre-filling of mechanical gaps in a very short time, thereby significantly reducing the response delay in subsequent braking actions.

[0027] After entering the pre-fill state, the system continuously monitors the brake pedal status in real time, while simultaneously tracking the accelerator pedal opening and vehicle speed changes. When the system detects that the driver has pressed the brake pedal, it immediately triggers the braking state switching logic, switching the control mode of the current electromechanical brake actuator from the small torque gap pre-fill state to the normal braking control state. During this switching process, the control strategy adopts a smooth transition method, continuously adjusting the output torque or current of the drive motor to rapidly but without abrupt changes increase the braking force from near zero to the target braking force, thereby avoiding vehicle jerking or instability caused by sudden changes in braking force.

[0028] During this smooth transition, braking pressure growth rate limiting or torque slope control can be introduced to ensure that the braking force build-up process is both rapid and smooth. Simultaneously, since the gap has been eliminated in advance, the braking actuator does not need to undergo the gap build-up phase, thus significantly reducing braking response time. This typically reduces response delay by tens of milliseconds or even higher, effectively lowering vehicle braking distance and improving safety performance under high-speed driving conditions.

[0029] On the other hand, when the system does not detect brake pedal action in the pre-fill state, it will continuously monitor the recovery of the accelerator pedal opening and whether the time window reaches the preset upper limit. When the accelerator pedal opening recovers to the normal driving range, or the pre-fill duration exceeds the preset time threshold, the system will determine that the current emergency braking intention has disappeared, thereby triggering the exit logic. During the exit process, the electromechanical brake actuator gradually retracts according to the preset release strategy, restoring the brake friction pair to the initial clearance state and avoiding residual braking force or dragging.

[0030] In exit control, a phased release method can be adopted, such as first reducing the drive motor current to a holding state and then gradually releasing it to zero, thereby avoiding the impact caused by the rapid separation of the braking friction pair. At the same time, to prevent system jitter caused by frequent triggering and exiting, a hysteresis mechanism or time-locking strategy can be introduced to keep the system in a stable state for a short period of time, thereby improving the overall control stability.

[0031] Furthermore, during the entire process of high-speed rapid throttle release prediction and pre-filling, the system can also combine wheel speed changes, vehicle longitudinal deceleration, and driving torque change trends for auxiliary judgment to further improve the accuracy of intent recognition. For example, when the throttle is released rapidly while accompanied by a slight increase in deceleration, the trigger confidence can be further improved; while when the throttle is released but the vehicle is still accelerating, pre-filling triggering can be suppressed, thereby reducing false judgments.

[0032] In practical engineering implementation, this control method can be implemented in the vehicle controller or brake controller through software algorithms, and adapted to different vehicle models, different braking system structures, and different driving style requirements by calibrating parameters. For example, high-performance vehicles can be set with a more sensitive trigger threshold to improve response speed, while comfort-oriented vehicles can appropriately reduce trigger sensitivity to reduce unnecessary pre-filling actions.

[0033] Through the complete control process described above, in the case of rapid release of the accelerator at high speed, the system can complete the braking preparation work in advance before the driver actually presses the brake pedal, thereby transforming the traditional "passive response braking" into "active anticipatory braking preparation". This significantly improves braking response performance and driving safety without affecting driving comfort. It is especially suitable for high-speed emergencies such as sudden deceleration of vehicles in front or sudden obstacles, and has significant engineering application value and safety improvement effect.

[0034] Implementation Method Two: In this implementation method, the Electronic Pre-Brake (EBP) pedal release prediction and pre-filling control method is applied to urban road environments where vehicles primarily operate at low or low-to-medium speeds, accompanied by typical traffic characteristics such as frequent following, starting and stopping, and slow movement. During operation, the system first continuously identifies the vehicle's driving state by collecting data on vehicle speed, wheel speed changes, accelerator pedal opening variations, and longitudinal dynamic response characteristics to classify the current operating condition. When the vehicle speed is within a preset low or low-to-medium speed range, and the wheel speed changes exhibit periodic fluctuations or maintain a consistent rhythm with the preceding vehicle, combined with the frequent small-amplitude opening and closing of the accelerator pedal, it can be determined that the vehicle is in a following-vehicle driving condition.

[0035] After completing the following-vehicle condition recognition, the system further enters the driving intention analysis stage, continuously monitoring the changes in accelerator pedal opening and its rate of change. By filtering and differentially calculating the accelerator pedal signal, a stable rate of change in accelerator pedal release can be obtained. When a decreasing trend in accelerator pedal opening is detected and the rate of change in release reaches the preset threshold range for the corresponding low-speed or following-vehicle condition, the system considers this behavior as a precursor to potential deceleration or braking intentions. Unlike high-speed conditions, in urban following-vehicle scenarios, driver operations are more frequent and the changes are smaller. Therefore, the threshold setting adopts a hierarchical structure, such as setting three levels: slight release, moderate release, and rapid release, and dynamically correcting it in conjunction with the vehicle's speed to avoid frequent false triggers.

[0036] Upon determining that a potential deceleration intention has been established, the system triggers the Electronic Pre-Brake (EBP) pre-fill state. In this state, the wheel control unit drives the electromechanical brake actuator to pre-fill the gap according to the control strategy matched to the current operating conditions. Due to the high requirements for comfort in urban driving conditions, the pre-fill control adopts a low-level, low-torque strategy. By precisely controlling the motor drive current or output torque, the brake friction pair slowly approaches the brake disc contact position. This process requires strict control of the pre-fill degree, ensuring that the friction pair approaches contact but does not enter the effective braking force range, thereby avoiding dragging or a feeling of deceleration in the vehicle.

[0037] During the small-torque gap pre-filling process, the system establishes a multi-dimensional dynamic adjustment mechanism to adjust the pre-filling duration and output torque in real time. The adjustment is based on parameters such as vehicle speed changes, wheel speed fluctuations, accelerator pedal opening recovery, and following stability. For example, when the vehicle is in a stable following state and the vehicle in front is showing a clear deceleration trend, the pre-filling duration can be appropriately extended and the pre-filling torque slightly increased to enhance braking response preparation; while when the vehicle is in a slow coasting state or a slight throttle adjustment state, the pre-filling intensity is reduced or even the triggering is delayed to avoid interfering with driving comfort.

[0038] In this dynamic adjustment process, time windows and hysteresis mechanisms can also be introduced. For example, a minimum hold time can be set after pre-filling triggering to avoid frequent entry and exit from the pre-filling state in a short period of time; at the same time, a recovery threshold can be set in the exit judgment, so that the accelerator pedal opening must recover to a certain extent before exiting is allowed, thereby avoiding repeated switching of the system in the critical state. In addition, the current driving intention can be further aided by monitoring the trend of changes in the vehicle's longitudinal acceleration. When the accelerator is released and deceleration increases, the trigger confidence is increased; conversely, the trigger weight is reduced.

[0039] During the pre-fill state, the system continuously monitors the brake pedal status. When the system detects that the driver has pressed the brake pedal, it immediately executes the state switching logic, smoothly transitioning the electromechanical brake actuator from the small torque gap pre-fill state to the normal braking state. During this transition, the braking force is continuously increased by gradually increasing the motor drive current or torque, avoiding sudden changes that could cause vehicle jerking. Because the gap has been eliminated in advance, the brake actuator can establish effective braking force in a very short time, thus significantly improving braking response speed, especially in urban low-speed, frequent braking scenarios.

[0040] When the system does not detect brake pedal action in the pre-fill state, it will continue to track changes in accelerator pedal opening and vehicle driving status. When the accelerator pedal opening gradually returns to the driving state, or the vehicle maintains a stable and uniform speed while following the vehicle in front without further deceleration, the system determines that the current pre-braking demand has disappeared, thereby triggering the exit control logic. During the exit process, the electromechanical brake actuator gradually retracts according to the preset release curve, restoring the brake friction pair to its initial clearance position. The release process also employs a smooth control strategy, gradually reducing the motor drive current to avoid mechanical shock or system vibration caused by rapid release.

[0041] In practical applications, the system can also adaptively adjust parameters based on different road environments and driving styles. For example, in heavily congested urban areas, the pre-filled trigger sensitivity can be appropriately increased to enhance safety redundancy; while on unobstructed roads, the trigger frequency can be reduced to minimize unnecessary control actions. Furthermore, thresholds can be personalized using historical driving data, allowing the system to gradually adapt to driver habits and achieve a better balance between safety and comfort.

[0042] Furthermore, during multi-condition adaptive control, the system can integrate more auxiliary information, such as the trend of changes in the distance to the vehicle ahead, road slope information, and environmental conditions, to further optimize the pre-fill strategy. For example, on downhill sections or slippery road surfaces, the pre-fill force can be appropriately increased to improve braking response; in flat and low-risk environments, the pre-fill strength can be reduced to decrease energy consumption and mechanical wear.

[0043] Through the aforementioned multi-condition adaptive pre-fill control method, the system can achieve precise braking intention prediction and flexible control in urban following and complex traffic environments, ensuring that the braking system maintains rapid response capability without affecting driving comfort. This method not only effectively reduces braking delay caused by sudden situations but also avoids vehicle drag or discomfort caused by excessive pre-fill, thus achieving a good balance between safety and comfort and significantly improving the vehicle's overall driving performance and user experience in urban road environments.

[0044] Implementation Method 3: In this implementation method, the Electronic Pre-Brake (EBP) pedal release prediction and pre-fill control method not only focuses on driver intent recognition and braking response optimization, but also emphasizes the introduction of active safety function interlock mechanisms and fault redundancy control strategies to improve the safety and reliability of the entire vehicle system under complex operating conditions. During system operation, the control unit continuously acquires the status information of various active safety functions of the vehicle and the validity status of key sensor signals, and dynamically constrains and controls the EBP function based on this information, thereby avoiding functional conflicts and malfunctions under abnormal conditions.

[0045] Regarding functional interlocking, the system monitors the operational status of the anti-lock braking system (ABS), vehicle stability control (VSC), and adaptive cruise control (ACC) in real time. When any active safety function is detected as active, the system immediately enters the functional interlock control mode. In this mode, the electronic pre-braking (EBP) triggering logic is prohibited. Even if conditions such as the rate of change in accelerator pedal release and vehicle speed meet the predicted triggering requirements, the system will not enter the pre-filling state. The core of this strategy is to ensure that there is no interference between different control functions. For example, during ABS operation, the braking actuator needs to make high-frequency adjustments based on wheel speed feedback. If pre-filling is superimposed at this time, it may lead to unstable braking control. When VSC intervenes, the system needs to independently adjust the braking force of each wheel. If there is additional pre-filling, it may disrupt the stability control effect. When adaptive cruise control is running, the system already has independent longitudinal control capabilities; triggering the pre-braking function at this time may cause control strategy conflicts. Therefore, by establishing a clear priority relationship, active safety functions always take precedence over electronic pre-braking (EBP), thereby ensuring the dynamic stability of the entire vehicle.

[0046] In terms of signal validity detection, the system continuously monitors the accelerator pedal signal, wheel speed signal, and brake pedal status signal, and determines whether the signals are in a normal state through various methods. Signal anomaly detection can be based on methods such as numerical range detection, rate of change detection, and multi-sensor consistency verification. For example, when the accelerator pedal opening signal experiences sudden changes, jumps, or exceeds a physically reasonable range, it can be considered an anomaly; when the wheel speed signal experiences unreasonable fluctuations within a short period or is inconsistent with the vehicle's speed, it can also be considered an anomaly; when the brake pedal signal exhibits continuous high-frequency jitter or changes that do not conform to driving logic, it also needs to be masked. Once the system determines that any key input signal is invalid, it enters a signal masking mode. In this mode, the Electronic Pre-Brake (EBP) function is disabled, thereby preventing false pre-filling triggers due to incorrect input and avoiding interference with vehicle operation or even safety risks.

[0047] In the fault handling mechanism, the system can also introduce a fault level classification strategy to determine the control behavior based on the severity of the fault. For example, for minor signal anomalies, a degraded control method can be used, only reducing the pre-fill trigger sensitivity; for severe signal faults, the electronic pre-braking (EBP) function is directly disabled. In addition, fault recovery conditions can be set. When the signal returns to normal and remains stable for a certain period of time, the system will then allow the electronic pre-braking function to participate in control again, thereby avoiding frequent system start-stops.

[0048] Regarding controller redundancy, the system adopts a dual-controller architecture, including a main controller and a redundant controller, both capable of performing Electronic Pre-Braking (EBP) prediction and pre-filling control. Under normal operating conditions, the main controller handles all calculation and control tasks, while the redundant controller remains in standby or synchronous operation mode, continuously receiving key input signals and performing synchronous calculations, but without outputting control commands. When the system detects an anomaly in the main controller, such as communication interruption, calculation error, or power failure, it immediately triggers the control switching logic.

[0049] During the control handover process, the system identifies the failure state of the main controller through a rapid judgment mechanism, such as heartbeat signal monitoring, task execution cycle detection, or output signal consistency verification. Once it is confirmed that the main controller is not working properly, the redundant controller takes over the control tasks in a very short time and continues to execute the electronic pre-braking (EBP) prediction and pre-filling control logic. Since the redundant controller has been running relevant algorithms and keeping data updated synchronously under normal conditions, it does not need to be re-initialized during takeover, achieving a seamless transition and thus avoiding control interruption.

[0050] After the redundant controller takes over, its execution strategy remains consistent with that of the main controller, including accelerator pedal release rate determination, multi-condition threshold judgment, and small torque clearance pre-fill control, ensuring consistent functional behavior. Simultaneously, the system can also share key status information between the main controller and the redundant controller through a state synchronization mechanism, such as whether it is currently in the pre-fill state, the current pre-fill progress, and the current condition identification result, thereby further improving the smoothness of the takeover.

[0051] Furthermore, in redundant control architectures, arbitration mechanisms can be introduced to prevent conflicts between the outputs of the two controllers. For example, in certain abnormal situations, the main controller may output abnormally while the redundant controller remains normal. In such cases, arbitration logic selects the controller with higher credibility to output control commands, thereby ensuring the reliability of the execution result. Arbitration criteria can include factors such as signal consistency, the rationality of control commands, and historical operational stability.

[0052] Throughout the active safety interlock and fault redundancy control process, the system can also be implemented in accordance with functional safety design standards. For example, by adding monitoring tasks, independent diagnostic channels, and safety state management mechanisms, the control strategy can meet high-level functional safety requirements. In the event of an unrecoverable fault, the system can enter a safe state, such as completely disabling the electronic pre-braking function while maintaining the basic functions of the braking system, thereby ensuring that the vehicle still has basic braking capability.

[0053] Through the aforementioned active safety interlock and fault redundancy control strategies, the Electronic Pre-Brake (EBP) function can maintain stable operation under complex and abnormal conditions. On the one hand, the functional interlock mechanism avoids conflicts with other active safety systems, ensuring vehicle dynamic stability; on the other hand, the signal detection and fault shielding mechanism prevents false triggering, improving system reliability; simultaneously, the dual-controller redundancy architecture ensures uninterrupted function in the event of a single point of failure, thereby significantly improving the safety level and robustness of the entire vehicle braking system.

[0054] This implementation method is particularly suitable for vehicle platforms with advanced driver assistance or autonomous driving functions. It has significant application value in multi-control system collaborative operation environments, and can provide the whole vehicle with more stable, safe and reliable braking pre-response capabilities, while meeting high-level functional safety requirements.

[0055] like Figure 2 As shown, this application provides an electronic pre-braking (EBP) pedal release prediction and pre-filling control system, including a pedal speed signal acquisition module, an intent recognition threshold determination module, a working condition triggering pre-braking module, a gap pre-filling execution module, a braking transition exit control module, and a safety constraint redundancy control module. The pedal speed signal acquisition module collects information such as accelerator pedal opening, accelerator pedal release rate, vehicle speed, wheel speed, brake pedal status, and vehicle driving conditions. The intent recognition threshold determination module sets multiple threshold ranges based on the rate of change of accelerator pedal release and vehicle speed to determine the driver's potential emergency braking intent. The working condition trigger pre-braking module enters the electronic pre-braking (EBP) pre-filling state when the judgment result meets any of the following conditions: high-speed rapid throttle release, following vehicle driving, or sudden pedal release. The gap prefilling execution module, based on the electronic pre-braking (EBP) prefilling state, controls the wheel control unit to drive the electromechanical brake actuator to perform small-torque gap prefilling to eliminate mechanical gaps; The brake transition exit control module monitors the brake pedal status during the small torque gap pre-filling process. When the brake pedal is detected to be pressed, a smooth transition from the pre-filling state to the normal braking state is executed. When the brake pedal is not pressed and the accelerator pedal is restored or the preset time limit is reached, the electronic pre-braking (EBP) pre-filling state is exited. The safety constraint redundancy control module performs control constraints based on the vehicle's active safety function status and signal validity status. When the anti-lock braking function, vehicle stability control function, or adaptive cruise control function is active, the electronic pre-braking (EBP) function is prohibited from being triggered. When the accelerator pedal signal or wheel speed signal is abnormal, the electronic pre-braking (EBP) function is disabled. When the main controller fails, the module switches to the redundant controller to perform prediction and pre-filling control.

[0056] The present invention provides an electronic pre-braking (EBP) pedal release prediction and pre-filling control method, which is implemented by the above-mentioned electronic pre-braking (EBP) pedal release prediction and pre-filling control system. For details of the specific method and process of the electronic pre-braking (EBP) pedal release prediction and pre-filling control system, please refer to the above-mentioned embodiment of the electronic pre-braking (EBP) pedal release prediction and pre-filling control method, which will not be repeated here.

[0057] The foregoing has only described certain exemplary embodiments of this application by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of this application. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of this application.

Claims

1. A method for electronic pre-braking (EBP) pedal release prediction and pre-filling control, characterized in that, Includes the following steps: Collect information on accelerator pedal opening, accelerator pedal release rate, vehicle speed, wheel speed, brake pedal status, and vehicle operating conditions. Based on the rate of change in accelerator pedal release and vehicle speed, multiple threshold ranges are set to determine the driver's potential emergency braking intention. When the judgment result meets any of the following conditions: high-speed rapid throttle release, following vehicle driving, or sudden pedal release, the electronic pre-braking (EBP) pre-fill state is entered. Based on the pre-fill state of the electronic pre-braking (EBP), the wheel control unit drives the electromechanical brake actuator to perform small torque clearance pre-filling to eliminate mechanical clearance. During the pre-filling process of the small torque gap, the brake pedal status is monitored. When the brake pedal is detected to be pressed, a smooth transition from the pre-filling state to the normal braking state is performed. When the brake pedal is not pressed and the accelerator pedal is restored or the preset time limit is reached, the electronic pre-braking (EBP) pre-filling state is exited. Control constraints are implemented based on the status of vehicle active safety functions and signal validity. When the anti-lock braking system, vehicle stability control, or adaptive cruise control is active, the electronic pre-braking (EBP) function is prohibited from being triggered. When the accelerator pedal signal or wheel speed signal is abnormal, the electronic pre-braking (EBP) function is disabled. When the main controller fails, the system switches to the redundant controller to perform prediction and pre-filling control.

2. The electronic pre-braking (EBP) pedal release prediction and pre-filling control method according to claim 1, characterized in that, The rate of change of accelerator pedal release is obtained by time-series sampling and differential calculation of the accelerator pedal opening signal, and the influence of high-frequency noise is eliminated by filtering algorithm. At the same time, the change amplitude within a preset time window is divided into multiple level intervals, and different level intervals correspond to different emergency braking intention judgment weights.

3. The electronic pre-braking (EBP) pedal release prediction and pre-filling control method according to claim 2, characterized in that, The multi-level threshold range is mapped by dividing the vehicle speed range. Different vehicle speed ranges correspond to different threshold ranges for the rate of change of accelerator pedal release. At the same time, the longitudinal acceleration change trend is introduced to participate in the judgment. When the rate of change of accelerator pedal release is in the same direction as the deceleration change, the trigger priority is increased.

4. The electronic pre-braking (EBP) pedal release prediction and pre-filling control method according to claim 1, characterized in that, The following driving condition is identified by combining the periodic characteristics of wheel speed fluctuations with the amplitude of vehicle speed changes. When the wheel speed changes periodically and the vehicle speed fluctuation range is within a preset range, it is determined to be a following state, and the pre-filled trigger conditions and duration parameters are adjusted in this state.

5. The electronic pre-braking (EBP) pedal release prediction and pre-filling control method according to claim 1, characterized in that, Small torque gap pre-filling is achieved by controlling the output current curve of the drive motor of the electromechanical braking actuator. The current curve adopts a piecewise function form, which limits the current growth rate when approaching the critical position of mechanical gap elimination, and judges the near contact state of the friction pair by the inflection point of current change.

6. The electronic pre-braking (EBP) pedal release prediction and pre-filling control method according to claim 1, characterized in that, The gap elimination state is determined by combining the trend of the drive motor current change with the displacement estimation model. When the current shows a stable upward trend and the displacement change slows down, it is determined that the gap critical position has been reached, and the pre-fill state is maintained to wait for braking trigger.

7. The electronic pre-braking (EBP) pedal release prediction and pre-filling control method according to claim 5, characterized in that, The pre-fill exit control adopts a phased release strategy, including a maintenance phase and a retraction phase. During the maintenance phase, the drive motor maintains a low current output, and during the retraction phase, the current is gradually reduced to zero, thereby avoiding mechanical shock and vehicle response fluctuations caused by rapid separation of the brake friction pair.

8. The electronic pre-braking (EBP) pedal release prediction and pre-filling control method according to claim 7, characterized in that, The pre-filling trigger and exit process introduces a time hysteresis control mechanism, which sets the minimum trigger duration and minimum exit delay time, and sets the exit judgment condition in combination with the accelerator pedal opening recovery range.

9. The electronic pre-braking (EBP) pedal release prediction and pre-filling control method according to claim 8, characterized in that, Signal validity detection includes range verification, rate of change verification, and multi-signal consistency verification of accelerator pedal signal, wheel speed signal, and brake pedal signal. When any signal does not meet the preset reasonable range or change pattern, it is marked as an abnormal state and the electronic pre-braking (EBP) is prohibited from being triggered.

10. An electronic pre-braking (EBP) pedal release prediction and pre-filling control system, used to implement the electronic pre-braking (EBP) pedal release prediction and pre-filling control method according to any one of claims 1-9, characterized in that, It includes a pedal speed signal acquisition module, an intent recognition threshold determination module, a working condition trigger pre-braking module, a gap pre-filling execution module, a braking transition exit control module, and a safety constraint redundancy control module; The pedal speed signal acquisition module collects information such as accelerator pedal opening, accelerator pedal release rate, vehicle speed, wheel speed, brake pedal status, and vehicle driving conditions. The intent recognition threshold determination module sets multiple threshold ranges based on the rate of change of accelerator pedal release and vehicle speed to determine the driver's potential emergency braking intent. The working condition trigger pre-braking module enters the electronic pre-braking (EBP) pre-filling state when the judgment result meets any of the following conditions: high-speed rapid throttle release, following vehicle driving, or sudden pedal release. The gap prefilling execution module, based on the electronic pre-braking (EBP) prefilling state, controls the wheel control unit to drive the electromechanical brake actuator to perform small-torque gap prefilling to eliminate mechanical gaps; The brake transition exit control module monitors the brake pedal status during the small torque gap pre-filling process. When the brake pedal is detected to be pressed, a smooth transition from the pre-filling state to the normal braking state is executed. When the brake pedal is not pressed and the accelerator pedal is restored or the preset time limit is reached, the electronic pre-braking (EBP) pre-filling state is exited. The safety constraint redundancy control module performs control constraints based on the vehicle's active safety function status and signal validity status. When the anti-lock braking function, vehicle stability control function, or adaptive cruise control function is active, the electronic pre-braking (EBP) function is prohibited from being triggered. When the accelerator pedal signal or wheel speed signal is abnormal, the electronic pre-braking (EBP) function is disabled. When the main controller fails, the module switches to the redundant controller to perform prediction and pre-filling control.

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