Force sensor failure detection method and device, electronic equipment and medium

Abstract

The invention provides a force sensor failure detection method and device, electronic equipment and a medium, and relates to the field of drive-by-wire chassis electronic control. The method comprises the steps that input information of an electronic mechanical braking system corresponding to a current vehicle is obtained; determining a first minimum clamping force and a first maximum clamping force, and a second minimum clamping force and a second maximum clamping force based on the input information; determining failure conditions of the force sensor according to the first minimum clamping force, the first maximum clamping force, the second minimum clamping force and the second maximum clamping force; and when the current clamping force value detected by the force sensor meets the failure condition of the force sensor, determining that the force sensor fails. The method is combined with threshold judgment, single-dimension errors are eliminated, and the failure detection accuracy of the force sensor is improved.

Description

Technical Field

[0001] This application relates to the field of drive-by-wire chassis electronic control, and more specifically, to a method, device, electronic equipment, and medium for detecting force sensor failure. Background Technology

[0002] With the development of automotive drive-by-wire chassis technology, electromechanical braking systems have gradually become an important development direction for next-generation automotive braking systems due to their elimination of hydraulic transmission structures, fast response speed, and high control precision. Currently, clamping force control schemes for electromechanical braking systems are mainly divided into two categories: one is the scheme equipped with force sensors, which directly detects the clamping force of the brake pads to form closed-loop control, and also has hardware backup redundancy, which can improve the functional safety level of the system, but the additional force sensors will increase the system cost; the other is the scheme without force sensors, which estimates the clamping force through models and uses it for closed-loop control. Although this can reduce costs, it lacks hardware redundancy and the system reliability is relatively low.

[0003] In electromechanical braking systems equipped with force sensors, the failure of the force sensor directly leads to invalid clamping force detection data. If this failure cannot be identified in a timely and accurate manner, the system will be unable to control based on the effective clamping force, potentially causing abnormal braking force or even brake failure, and consequently resulting in serious traffic accidents. Current technologies often rely on the correlation between motor torque and the clamping force detected by the force sensor (i.e., the clamping force should increase synchronously when the motor torque increases, and vice versa). However, this method is overly dependent on the accuracy of motor torque detection. When the motor torque deviates due to detection errors, transmission system disturbances, or other factors, it is easy to misjudge the force sensor as faulty, or when the force sensor actually fails, the torque deviation may cause a detection delay. Summary of the Invention

[0004] The purpose of this application is to provide a method, device, electronic device and medium for detecting force sensor failure, so as to solve the above-mentioned problems existing in the prior art, and to quickly and accurately detect the failure of force sensor in electromechanical braking system, thereby ensuring driving safety.

[0005] Firstly, a method for detecting force sensor failure is provided, which may include: Obtain the input information of the current vehicle's electromechanical braking system; Based on the input information, determine the motor load torque and ball screw stroke; Based on the motor load torque and the ball screw stroke, determine the first clamping force corresponding to the motor load torque and the second clamping force corresponding to the ball screw stroke; Based on the configured threshold adjustment coefficient, the first clamping force and the second clamping force are adjusted respectively to obtain the first minimum clamping force and the first maximum clamping force corresponding to the first clamping force, and the second minimum clamping force and the second maximum clamping force corresponding to the second clamping force; The failure condition of the force sensor is determined based on the first minimum clamping force, the first maximum clamping force, the second minimum clamping force, and the second maximum clamping force. When the current clamping force value detected by the force sensor meets the failure condition of the force sensor, the force sensor is determined to be faulty.

[0006] In one possible implementation, the input information includes at least the motor output torque, the current motor speed, the motor moment of inertia, the transmission efficiency, the transmission ratio, the motor position data, and the current clamping force value detected by the force sensor.

[0007] In one possible implementation, determining the motor load torque based on the input information includes: The motor acceleration is determined based on the current motor speed, the motor speed at the previous moment, and the time interval. The motor load torque is determined based on the motor acceleration, the motor moment of inertia, and the motor output torque.

[0008] In one possible implementation, determining the ball screw travel based on the input information includes: The ball screw stroke is determined based on the motor position data and the configured conversion ratio constant; wherein the conversion ratio constant is obtained by calibrating the mechanical properties of the ball screw in the electromechanical braking system.

[0009] In one possible implementation, determining the second clamping force corresponding to the ball screw stroke includes: The second clamping force is obtained by calculating the stroke of the ball screw using a configured polynomial fitting relationship.

[0010] In one possible implementation, the threshold adjustment coefficient includes a first minimum adjustment coefficient, a first maximum adjustment coefficient, a second minimum adjustment coefficient, and a second maximum adjustment coefficient; Based on the configured threshold adjustment coefficients, the first clamping force and the second clamping force are adjusted respectively to obtain the first minimum clamping force and the first maximum clamping force corresponding to the first clamping force, and the second minimum clamping force and the second maximum clamping force corresponding to the second clamping force, including: The first clamping force is processed using the first minimum adjustment coefficient to obtain the first minimum clamping force; The first clamping force is processed using the first maximum adjustment coefficient to obtain the first maximum clamping force; The second clamping force is processed using the second minimum adjustment coefficient to obtain the second minimum clamping force; The second clamping force is processed using the second maximum adjustment coefficient to obtain the second maximum clamping force.

[0011] In one possible implementation, the failure condition of the force sensor is: The current clamping force value is simultaneously less than both the first minimum clamping force and the second minimum clamping force, or the current clamping force value is simultaneously greater than both the first maximum clamping force and the second maximum clamping force; and the duration reaches the configured preset time threshold.

[0012] Secondly, a force sensor failure detection device is provided, which may include: The acquisition unit is used to acquire the input information of the electromechanical braking system corresponding to the current vehicle. The determining unit is used to determine the motor load torque and ball screw stroke based on the input information; Furthermore, based on the motor load torque and the ball screw travel, a first clamping force corresponding to the motor load torque and a second clamping force corresponding to the ball screw travel are determined; The adjustment unit is used to adjust the first clamping force and the second clamping force according to the configured threshold adjustment coefficient, respectively, to obtain the first minimum clamping force and the first maximum clamping force corresponding to the first clamping force, and the second minimum clamping force and the second maximum clamping force corresponding to the second clamping force; The determining unit is further configured to determine the force sensor failure condition based on the first minimum clamping force, the first maximum clamping force, the second minimum clamping force, and the second maximum clamping force; The determination unit is also used to determine that the force sensor is faulty when the current clamping force value detected by the force sensor meets the failure condition of the force sensor.

[0013] Thirdly, an electronic device is provided, which includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; When a processor executes a program stored in memory, it implements any of the steps described in the first aspect above.

[0014] Fourthly, a computer-readable storage medium is provided, wherein a computer program is stored therein, and when executed by a processor, the computer program implements the steps of any of the methods described in the first aspect above.

[0015] This application provides a method, apparatus, electronic device, and medium for detecting force sensor failure, relating to the field of drive-by-wire chassis electronic control. The method includes: acquiring input information of the electromechanical braking system corresponding to the current vehicle; determining the motor load torque and ball screw travel based on the input information; determining a first clamping force corresponding to the motor load torque and a second clamping force corresponding to the ball screw travel based on the motor load torque and ball screw travel; adjusting the first clamping force and the second clamping force according to a configured threshold adjustment coefficient to obtain a first minimum clamping force and a first maximum clamping force corresponding to the first clamping force, and a second minimum clamping force and a second maximum clamping force corresponding to the second clamping force; determining the force sensor failure condition based on the first minimum clamping force, the first maximum clamping force, the second minimum clamping force, and the second maximum clamping force; and determining the force sensor failure when the current clamping force value detected by the force sensor meets the force sensor failure condition. This application addresses the failure detection of force sensors in electromechanical braking systems, offering several advantages: First, it solves the problem of misjudgment caused by existing technologies relying solely on motor torque. By using a dual-dimensional benchmark—the first clamping force corresponding to the motor load torque and the second clamping force corresponding to the ball screw stroke—combined with threshold judgment, it eliminates single-dimensional errors and improves detection accuracy. Second, it reuses existing system parameters, requiring no additional hardware, resulting in low implementation costs. Furthermore, the process is seamless and responsive, meeting the need for rapid fault identification. Third, accurate failure detection directly provides a basis for switching to model-based clamping force control, preventing braking safety issues caused by force sensor failure and ensuring vehicle driving safety. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A system architecture diagram for a method of detecting force sensor failure provided in an embodiment of this application; Figure 2 A flowchart illustrating a method for detecting force sensor failure provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of a force sensor failure detection device provided in an embodiment of this application; Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0018] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0019] The force sensor failure detection method provided in this application embodiment can be applied to... Figure 1 In the system architecture shown, such as Figure 1 As shown, the system may include an electromechanical braking system and a processor; An electromechanical braking system is used to receive vehicle data sent by various sensors, use the vehicle data as input information for the system, and send the input information to the processor; The processor is used to execute the force sensor failure detection method provided in this application.

[0020] This application belongs to the field of drive-by-wire chassis electronic control, specifically involving electromechanical braking control technology (electromechanical braking system, EMB), which is particularly suitable for scenarios where the motor realizes electronic power-assisted braking control through gear and rack, worm gear transmission system and ball screw transmission system. The core is used to detect the failure state of the force sensor in the electromechanical braking system to ensure the safe and reliable operation of the braking system.

[0021] With the development of automotive drive-by-wire chassis technology, electromechanical braking systems have gradually become an important development direction for next-generation automotive braking systems due to their elimination of hydraulic transmission structures, fast response speed, and high control precision. Currently, clamping force control schemes for electromechanical braking systems are mainly divided into two categories: one is the scheme equipped with force sensors, which directly detects the clamping force of the brake pads to form closed-loop control, and also has hardware backup redundancy, which can improve the functional safety level of the system, but the additional force sensors will increase the system cost; the other is the scheme without force sensors, which estimates the clamping force through models and uses it for closed-loop control. Although this can reduce costs, it lacks hardware redundancy and the system reliability is relatively low.

[0022] In electromechanical braking systems equipped with force sensors, the failure of the force sensor directly leads to invalid clamping force detection data. If this failure cannot be identified in a timely and accurate manner, the system will be unable to control based on the effective clamping force, potentially causing abnormal braking force or even brake failure, and consequently resulting in serious traffic accidents. Current technologies often rely on the correlation between motor torque and the clamping force detected by the force sensor (i.e., the clamping force should increase synchronously when the motor torque increases, and vice versa). However, this method is overly dependent on the accuracy of motor torque detection. When the motor torque deviates due to detection errors, transmission system disturbances, or other factors, it is easy to misjudge the force sensor as faulty, or when the force sensor actually fails, the torque deviation may cause a detection delay.

[0023] Therefore, this application provides a method for detecting force sensor failure, which solves the above-mentioned problems existing in the prior art, and can quickly and accurately detect the failure of force sensors in electromechanical braking systems, thus ensuring driving safety.

[0024] The preferred embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit this application. Furthermore, the embodiments and features in the embodiments of this application can be combined with each other without conflict.

[0025] Figure 2 This is a flowchart illustrating a method for detecting force sensor failure provided in an embodiment of this application. Figure 2 As shown, the method may include: Step S210: Obtain the input information of the electromechanical braking system corresponding to the current vehicle.

[0026] The input information includes at least the motor output torque, the current motor speed, the motor moment of inertia, the transmission efficiency, the transmission ratio, the motor position data, and the current clamping force value detected by the force sensor.

[0027] Motor output torque refers to the torque value output by the drive motor in the electromechanical braking system during real-time braking. This value directly reflects the amount of power provided by the motor to drive the brake actuator (ball screw, etc.). It is obtained by real-time acquisition by the motor controller and feedback to the electromechanical braking system.

[0028] The current speed of the motor refers to the instantaneous speed of the drive motor during real-time operation, reflecting the dynamic operating status of the motor-driven brake actuator; it is obtained in real time through a motor position sensor or speed sensor.

[0029] The moment of inertia of a motor refers to the inertial parameter that the drive motor has when it rotates. It is an inherent property of the motor and does not change with real-time operating conditions. It is obtained by calibrating the motor characteristics through testing before the system leaves the factory and pre-stored in the control unit of the electromechanical braking system. When calculating the motor load torque in the future, it is used to deduct the inertial torque generated by the motor due to acceleration / deceleration, so as to ensure that the motor load torque can accurately reflect the actual load of the drive brake actuator.

[0030] Transmission efficiency refers to the effective proportion of power transmission in the power transmission chain (including gear and rack, worm gear and ball screw transmission systems) of an electromechanical braking system, reflecting the degree of energy loss during the transmission process.

[0031] The transmission ratio refers to the speed / torque transmission ratio between the output shaft of the drive motor and the ball screw (the core component of the brake actuator), which determines the torque amplification factor when the motor power is transmitted to the brake actuator.

[0032] Motor position data refers to the real-time rotational position information of the drive motor rotor, which is directly related to the displacement state of the ball screw; it is obtained in real time through the position sensors built into the motor (such as Hall sensors and encoders).

[0033] The current clamping force value detected by the force sensor refers to the brake pad clamping force data detected in real time by the clamping force sensor in the electromechanical braking system.

[0034] Step S220: Based on the input information, determine the motor load torque and ball screw stroke.

[0035] Specifically, A. Determining the motor load torque may include: The motor acceleration is determined based on the current motor speed, the motor speed at the previous moment, and the time interval. The motor load torque is determined based on the motor acceleration, motor moment of inertia, and motor output torque. This process can be expressed by the following formula:

[0036] in, This is the motor load torque. For the motor output torque, The moment of inertia of the motor. This refers to the acceleration of the motor.

[0037] This process can eliminate the interference of the motor's own inertia on the effective power (such as when the motor starts and accelerates, some of the output torque is used to overcome its own inertia rather than drive the brake), ensuring that the motor load torque can accurately match the actual load state of the brake actuator, laying the foundation for the accuracy of the subsequent first theoretical clamping force.

[0038] B. Determining the ball screw travel may include: The ball screw stroke is determined based on the motor position data and the configured conversion ratio constant. The conversion proportional constant is obtained by calibrating the mechanical properties of the ball screw in the electromechanical braking system. The conversion proportional constant is a fixed conversion factor between the motor's rotational motion and the ball screw's linear displacement, and its value is determined by the ball screw's mechanical properties (primarily the pitch, i.e., the linear displacement corresponding to one revolution of the ball screw). For example, if the ball screw pitch is 5mm, then for every one revolution of the motor, the ball screw's linear displacement is 5mm; in this case, the conversion proportional constant is 5mm / revolution. This constant needs to be determined during the system bench calibration phase: through bench testing, the motor is controlled to rotate a fixed number of revolutions, the actual linear displacement of the ball screw is measured, the displacement / rotation ratio is calculated, and after multiple verifications, it is pre-stored in the system to ensure the accuracy of the conversion relationship (avoiding deviations in stroke calculation due to machining errors).

[0039] The expression for determining the ball screw stroke is:

[0040] in, For the ball screw stroke, For motor position data, This is the conversion proportionality constant.

[0041] Step S230: Based on the motor load torque and the ball screw stroke, determine the first clamping force corresponding to the motor load torque and the second clamping force corresponding to the ball screw stroke.

[0042] Specifically, A. The motor load torque needs to be transmitted to the ball screw through the transmission system, which in turn drives the brake pads to clamp. The transmission ratio determines the amplification factor of the motor torque to the actuator (e.g., when the transmission ratio is 5, the motor torque is 1N). The torque of m can be amplified to 5N. m acts on the lead screw), and the transmission efficiency corrects for the power loss during the transmission process (e.g., when the efficiency is 0.9, only 90% of the torque can be effectively transmitted to the actuator).

[0043] The process of determining the first clamping force is as follows: through the coordinated calculation of motor load torque, transmission ratio, and transmission efficiency, the effective power of the motor is quantified into the theoretical clamping force of the brake pads.

[0044] The expression for calculating the first clamping force is:

[0045] in, For the first clamping force, This is the motor load torque. The transmission ratio is... For transmission efficiency.

[0046] B. Using the configured polynomial fitting relationship, the ball screw stroke is calculated to obtain the second clamping force.

[0047] Specifically, the linear displacement of the ball screw directly determines the clamping stroke of the brake pads. However, due to the nonlinearity of the mechanical structure (such as the contact gap between the brake pads and the brake disc, and the change in the coefficient of friction), the relationship between the screw stroke and the clamping force is not simply linear and needs to be established through experimental calibration to establish a precise correlation.

[0048] Based on the above characteristics, the second clamping force is determined as follows: multiple sets of measured data of clamping force corresponding to the screw stroke are obtained through bench tests, a correlation is established by polynomial fitting, and then the theoretical clamping force is derived from the real-time screw stroke based on this relationship.

[0049] The polynomial fitting relationship can be expressed as:

[0050] in, For the second clamping force, Let be the ball screw stroke, and a, b, and c be the polynomial fitting coefficients.

[0051] In some embodiments, the derivation of the second clamping force is based on the fitting relationship between mechanical displacement and clamping force: after substituting the real-time acquired ball screw stroke into a pre-stored polynomial fitting formula, the corresponding theoretical clamping force can be directly obtained. The degree of the polynomial in the fitting relationship can be adjusted according to the degree of mechanical nonlinearity of the system (e.g., a cubic polynomial is used when the nonlinearity is obvious, and a quadratic polynomial is used when the linearity is good) to ensure that the clamping force changes under different strokes can be accurately covered, and to avoid deviations in theoretical values ​​due to mechanical errors.

[0052] Step S240: Adjust the first clamping force and the second clamping force according to the configured threshold adjustment coefficient to obtain the first minimum clamping force and the first maximum clamping force corresponding to the first clamping force, and the second minimum clamping force and the second maximum clamping force corresponding to the second clamping force.

[0053] The threshold adjustment coefficient includes a first minimum adjustment coefficient, a first maximum adjustment coefficient, a second minimum adjustment coefficient, and a second maximum adjustment coefficient. Specifically, the first minimum adjustment coefficient is used to process the first clamping force to obtain the first minimum clamping force; The expression for the first minimum clamping force is: ,in, The first minimum clamping force, The first minimum adjustment coefficient, This is the first clamping force. For example, if the first clamping force is 1000N and the first minimum adjustment coefficient is 0.7, then the first minimum clamping force is 700N.

[0054] The first clamping force is processed using the first maximum adjustment coefficient to obtain the first maximum clamping force; The expression for the first maximum clamping force is: ;in, The first maximum clamping force, The first maximum adjustment coefficient, This is the first clamping force.

[0055] The second minimum clamping force is obtained by applying the second minimum adjustment coefficient to the second clamping force. The expression for the second minimum clamping force is: ,in, The second minimum clamping force, The second minimum adjustment coefficient, This is the second clamping force.

[0056] The second maximum clamping force is obtained by using the second maximum adjustment coefficient to process the second clamping force.

[0057] The expression for the second maximum clamping force is: ,in, The second maximum clamping force, The second largest adjustment coefficient, This is the second clamping force.

[0058] Furthermore, the first minimum adjustment coefficient, the first maximum adjustment coefficient, the second minimum adjustment coefficient, and the second maximum adjustment coefficient need to be determined through multi-condition calibration, rather than being fixed values.

[0059] Under various working conditions, the actual clamping force and the system's first / second clamping force are synchronously collected using high-precision reference equipment (such as third-party force sensors or laser displacement sensors). The deviation range between the two types of clamping forces and the actual clamping force is statistically analyzed. For example, if the deviation between the first clamping force and the actual clamping force does not exceed ±30% at a 95% confidence level, then the first minimum adjustment coefficient can be calibrated to 0.7 (first clamping force × 0.7 is the lower limit) and the first maximum adjustment coefficient can be calibrated to 1.3 (first clamping force × 1.3 is the upper limit).

[0060] In summary, this step, through four types of calibrated threshold adjustment coefficients, constructs a precise safety fluctuation range for the two types of theoretical clamping forces, which is compatible with the inherent errors of the system and provides a reliable benchmark for subsequent failure determination.

[0061] Step S250: Determine the force sensor failure condition based on the first minimum clamping force, the first maximum clamping force, the second minimum clamping force, and the second maximum clamping force; and determine that the force sensor has failed when the current clamping force value detected by the force sensor meets the force sensor failure condition.

[0062] Specifically, transient interference signals may exist during system operation (such as brief data jumps caused by sensor electromagnetic interference). If failure is determined solely based on transient out-of-tolerance conditions, false alarms are likely to occur. Therefore, the force sensor failure conditions determined in this step include two types of out-of-tolerance scenarios and time verification requirements.

[0063] Failure condition one: When the force sensor detects the current clamping force value in real time (denoted as...) Simultaneously satisfy: <First minimum clamping force, and The second minimum clamping force triggers the first type of failure scenario.

[0064] The two minimum clamping force thresholds in this failure condition represent the minimum reasonable clamping force allowed in the dynamic dimension (the first minimum clamping force) and the minimum reasonable clamping force allowed in the displacement dimension, respectively. If the sensor detection value is simultaneously lower than these two lower limits, it indicates that: From the power perspective, the effective torque output by the motor (which has been converted into the first clamping force) is sufficient to support a higher clamping force, but the sensor did not detect it; From a mechanical point of view, the displacement of the ball screw (which has been converted into a second clamping force) is sufficient to support a higher clamping force, but the sensor still did not detect it; Both findings indicate that the sensor's detected value is significantly lower than the clamping force that the system can actually provide. This rules out system problems such as insufficient power or mechanical jamming, and it can be preliminarily determined that the sensor has a failure due to low detected value (such as sensor signal attenuation or poor circuit contact).

[0065] For example: the first minimum clamping force = 700N (first clamping force 1000N × 0.7), the second minimum clamping force = 630N (second clamping force 900N × 0.7); when the sensor detection value = 600N, the failure scenario is triggered simultaneously, satisfying both 600N < 700N and 600N < 630N.

[0066] Failure condition two: When the force sensor detects the current clamping force value in real time (denoted as...) Simultaneously satisfy: >First maximum clamping force and > The second maximum clamping force triggers the second type of failure judgment scenario.

[0067] The two maximum clamping force thresholds in this failure condition represent the maximum reasonable clamping force allowed in the dynamic dimension (the first maximum clamping force) and the maximum reasonable clamping force allowed in the displacement dimension, respectively. If the sensor detection value is higher than both of these upper limits simultaneously, it indicates that: From the power perspective, the effective torque output by the motor can only support a limited clamping force (the first maximum clamping force), but the sensor detection value far exceeds this range; From a mechanical perspective, the displacement of the ball screw can only support a limited clamping force (the second maximum clamping force), but the sensor detection value still far exceeds this range; Both findings indicate that the sensor's detected value is significantly higher than the clamping force that the system can actually provide. This eliminates system problems such as instantaneous increase in transmission efficiency or displacement measurement deviation, and it can be preliminarily determined that the sensor has a failure due to an excessively high detected value (such as sensor signal drift or overload damage).

[0068] For example: the first maximum clamping force = 1300N (first clamping force 1000N × 1.3), the second maximum clamping force = 1170N (second clamping force 900N × 1.3); when the sensor detection value = 1400N, both 1400N > 1300N and 1400N > 1170N are satisfied, triggering this failure scenario.

[0069] Regardless of which of the above failure scenarios is triggered, the force sensor failure can only be determined if the duration of the out-of-tolerance state reaches a preset time threshold. If the out-of-tolerance state does not last for the time threshold (e.g., it only changes momentarily and then returns to normal), it is determined to be a normal fluctuation of the system and is not considered a sensor failure.

[0070] This method may encounter transient disturbances during system operation, such as electromagnetic interference and sensor signal noise (e.g., signal jumps caused by motor current fluctuations during braking). These disturbances are usually extremely short-lived (e.g., less than 1 ms) and do not necessarily indicate actual sensor failure. By setting a time threshold, such interference can be effectively filtered out, avoiding false alarms of force sensor failure.

[0071] Furthermore, the preset time threshold needs to be determined through multi-condition calibration. For example, different interference scenarios (such as electromagnetic interference and mechanical vibration) are simulated on a test bench, the duration of the interference signal is recorded, and the time threshold is set to be greater than the duration of the interference and less than the duration of the abnormal signal after the sensor fails (usually calibrated to 1ms~100ms) to ensure that interference can be filtered out and real failures can be quickly identified.

[0072] In summary, this step, through the design of failure conditions based on two dimensions of out-of-tolerance and duration, not only accurately identifies actual force sensor failures but also effectively filters out normal system fluctuations and transient interferences. It is the core objective of achieving rapid and accurate detection of force sensor failures and provides a clear basis for judgment on the braking safety of the EMB system.

[0073] In some embodiments, after detecting a failure of the force sensor, the method may further include: The clamping force can be selected as either the first clamping force (estimated based on the motor load torque as a dynamic dimension), the second clamping force (estimated based on the ball screw travel as a displacement dimension), or a combination of both. For example, in low-speed braking conditions, the ball screw travel measurement accuracy is higher, so the second clamping force is preferred. In high-speed emergency braking conditions, the motor load torque response is faster, so the first clamping force is preferred. The combined value is then obtained by combining the advantages of both through a weighted algorithm (the weights are determined by bench calibration) to further improve the estimation accuracy. Furthermore, the first clamping force and the second clamping force will be updated in real time according to the parameter acquisition cycle (e.g., 10ms / time). For example, when the motor load torque changes due to the adjustment of the brake pedal depth, the first clamping force is updated synchronously; when the ball screw stroke changes with the motor position, the second clamping force is updated synchronously, ensuring that the clamping force of the backup control is always matched with the actual braking requirements.

[0074] In some embodiments, after backup control is activated, the ECU will simultaneously monitor the rationality of the first clamping force and the second clamping force. For example, if the deviation between the first clamping force and the second clamping force exceeds a preset range (e.g., 20%), the ECU will determine that the estimation is abnormal and activate a higher level of safety strategy (e.g., switch to pure mechanical braking or limit braking force) to further improve the system redundancy safety level. To prevent drivers from being unaware of sensor failures, the ECU will display brake system fault indicator lights (such as a yellow ABS fault light or a red brake fault light) on the vehicle's instrument panel. At the same time, it can also indicate through the vehicle's information system (such as the central control screen) that the brake system is working normally but needs to be checked as soon as possible. This balances safety and user experience and ensures that fault information is effectively transmitted.

[0075] This application provides a method for detecting force sensor failure. The method includes: acquiring input information of the electromechanical braking system corresponding to the current vehicle; determining the motor load torque and ball screw stroke based on the input information; determining a first clamping force corresponding to the motor load torque and a second clamping force corresponding to the ball screw stroke based on the motor load torque and ball screw stroke; adjusting the first clamping force and the second clamping force according to a configured threshold adjustment coefficient to obtain a first minimum clamping force and a first maximum clamping force corresponding to the first clamping force, and a second minimum clamping force and a second maximum clamping force corresponding to the second clamping force; determining the force sensor failure condition based on the first minimum clamping force, the first maximum clamping force, the second minimum clamping force, and the second maximum clamping force; and determining the force sensor failure when the current clamping force value detected by the force sensor meets the force sensor failure condition. This application addresses the failure detection of force sensors in electromechanical braking systems, offering several advantages: First, it solves the problem of misjudgment caused by existing technologies relying solely on motor torque. By using a dual-dimensional benchmark—the first clamping force corresponding to the motor load torque and the second clamping force corresponding to the ball screw stroke—combined with threshold judgment, it eliminates single-dimensional errors and improves detection accuracy. Second, it reuses existing system parameters, requiring no additional hardware, resulting in low implementation costs. Furthermore, the process is seamless and responsive, meeting the need for rapid fault identification. Third, accurate failure detection directly provides a basis for switching to model-based clamping force control, preventing braking safety issues caused by force sensor failure and ensuring vehicle driving safety.

[0076] Corresponding to the above method, embodiments of this application also provide a detection device for force sensor failure, such as... Figure 3 As shown, the device includes: The acquisition unit 310 is used to acquire the input information of the electromechanical braking system corresponding to the current vehicle. The determining unit 320 is used to determine the motor load torque and ball screw stroke based on the input information; Furthermore, based on the motor load torque and the ball screw travel, a first clamping force corresponding to the motor load torque and a second clamping force corresponding to the ball screw travel are determined; The adjustment unit 330 is used to adjust the first clamping force and the second clamping force according to the configured threshold adjustment coefficient, respectively, to obtain the first minimum clamping force and the first maximum clamping force corresponding to the first clamping force, and the second minimum clamping force and the second maximum clamping force corresponding to the second clamping force; The determining unit 320 is further configured to determine the force sensor failure condition based on the first minimum clamping force, the first maximum clamping force, the second minimum clamping force, and the second maximum clamping force; The determination unit 340 is also used to determine that the force sensor is faulty when the current clamping force value detected by the force sensor meets the failure condition of the force sensor.

[0077] The functions of each unit in the force sensor failure detection device provided in the above embodiments of this application can be implemented through the above methods and steps. Therefore, the specific working process and beneficial effects of each unit in the force sensor failure detection device provided in the embodiments of this application will not be repeated here.

[0078] This application also provides an electronic device, such as... Figure 4 As shown, it includes a processor 410, a communication interface 420, a memory 430, and a communication bus 440, wherein the processor 410, the communication interface 420, and the memory 430 communicate with each other through the communication bus 440.

[0079] Memory 430 is used to store computer programs; When the processor 410 executes the program stored in the memory 430, it performs the following steps: Obtain the input information of the current vehicle's electromechanical braking system; Based on the input information, determine the motor load torque and ball screw stroke; Based on the motor load torque and the ball screw stroke, determine the first clamping force corresponding to the motor load torque and the second clamping force corresponding to the ball screw stroke; Based on the configured threshold adjustment coefficient, the first clamping force and the second clamping force are adjusted respectively to obtain the first minimum clamping force and the first maximum clamping force corresponding to the first clamping force, and the second minimum clamping force and the second maximum clamping force corresponding to the second clamping force; The failure condition of the force sensor is determined based on the first minimum clamping force, the first maximum clamping force, the second minimum clamping force, and the second maximum clamping force. When the current clamping force value detected by the force sensor meets the failure condition of the force sensor, the force sensor is determined to be faulty.

[0080] The communication bus mentioned above can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in the diagram, but this does not mean that there is only one bus or one type of bus.

[0081] The communication interface is used for communication between the aforementioned electronic devices and other devices.

[0082] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0083] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0084] The implementation methods and beneficial effects of the various components of the electronic device in the above embodiments for solving the problem can be found in [reference needed]. Figure 2 The steps in the illustrated embodiments are used to implement the electronic device. Therefore, the specific working process and beneficial effects of the electronic device provided in this application will not be repeated here.

[0085] In another embodiment provided in this application, a computer-readable storage medium is also provided, which stores instructions that, when executed on a computer, cause the computer to perform a method for detecting the failure of a force sensor as described in any of the above embodiments.

[0086] In another embodiment provided in this application, a computer program product containing instructions is also provided, which, when run on a computer, causes the computer to execute a method for detecting the failure of a force sensor as described in any of the above embodiments.

[0087] Those skilled in the art will understand that the embodiments in this application can be provided as methods, systems, or computer program products. Therefore, the embodiments in this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the embodiments in this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0088] This application describes embodiments of methods, apparatus (systems), and computer program products according to embodiments of this application with reference to flowchart illustrations and / or block diagrams. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0089] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0090] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0091] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected," "coupled," or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0092] Although preferred embodiments have been described in this application, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the embodiments in this application are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments in this application.

[0093] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of the embodiments of this application. Therefore, if these modifications and variations to the embodiments of this application fall within the scope of the embodiments of this application and their equivalents, then these modifications and variations are also intended to be included in the embodiments of this application.

Claims

1. A method for detecting force sensor failure, characterized in that, The method includes: Obtain the input information of the current vehicle's electromechanical braking system; Based on the input information, determine the motor load torque and ball screw stroke; Based on the motor load torque and the ball screw stroke, determine the first clamping force corresponding to the motor load torque and the second clamping force corresponding to the ball screw stroke; Based on the configured threshold adjustment coefficient, the first clamping force and the second clamping force are adjusted respectively to obtain the first minimum clamping force and the first maximum clamping force corresponding to the first clamping force, and the second minimum clamping force and the second maximum clamping force corresponding to the second clamping force; The failure condition of the force sensor is determined based on the first minimum clamping force, the first maximum clamping force, the second minimum clamping force, and the second maximum clamping force. When the current clamping force value detected by the force sensor meets the failure condition of the force sensor, the force sensor is determined to be faulty.

2. The method as described in claim 1, characterized in that, The input information includes at least the motor output torque, the current motor speed, the motor moment of inertia, the transmission efficiency, the transmission ratio, the motor position data, and the current clamping force value detected by the force sensor.

3. The method as described in claim 2, characterized in that, Based on the input information, the motor load torque is determined, including: The motor acceleration is determined based on the current motor speed, the motor speed at the previous moment, and the time interval. The motor load torque is determined based on the motor acceleration, the motor moment of inertia, and the motor output torque.

4. The method as described in claim 2, characterized in that, Based on the input information, the ball screw stroke is determined, including: The ball screw stroke is determined based on the motor position data and the configured conversion ratio constant; wherein the conversion ratio constant is obtained by calibrating the mechanical properties of the ball screw in the electromechanical braking system.

5. The method as described in claim 1, characterized in that, Determining the second clamping force corresponding to the ball screw stroke includes: The second clamping force is obtained by calculating the stroke of the ball screw using a configured polynomial fitting relationship.

6. The method as described in claim 1, characterized in that, The threshold adjustment coefficient includes a first minimum adjustment coefficient, a first maximum adjustment coefficient, a second minimum adjustment coefficient, and a second maximum adjustment coefficient; Based on the configured threshold adjustment coefficients, the first clamping force and the second clamping force are adjusted respectively to obtain the first minimum clamping force and the first maximum clamping force corresponding to the first clamping force, and the second minimum clamping force and the second maximum clamping force corresponding to the second clamping force, including: The first clamping force is processed using the first minimum adjustment coefficient to obtain the first minimum clamping force; The first clamping force is processed using the first maximum adjustment coefficient to obtain the first maximum clamping force; The second clamping force is processed using the second minimum adjustment coefficient to obtain the second minimum clamping force; The second clamping force is processed using the second maximum adjustment coefficient to obtain the second maximum clamping force.

7. The method as described in claim 1, characterized in that, The failure condition of the force sensor is: The current clamping force value is simultaneously less than both the first minimum clamping force and the second minimum clamping force, or the current clamping force value is simultaneously greater than both the first maximum clamping force and the second maximum clamping force; and the duration reaches the configured preset time threshold.

8. A detection device for force sensor failure, characterized in that, The device includes: The acquisition unit is used to acquire the input information of the electromechanical braking system corresponding to the current vehicle. The determining unit is used to determine the motor load torque and ball screw stroke based on the input information; Furthermore, based on the motor load torque and the ball screw travel, a first clamping force corresponding to the motor load torque and a second clamping force corresponding to the ball screw travel are determined; The adjustment unit is used to adjust the first clamping force and the second clamping force according to the configured threshold adjustment coefficient, respectively, to obtain the first minimum clamping force and the first maximum clamping force corresponding to the first clamping force, and the second minimum clamping force and the second maximum clamping force corresponding to the second clamping force; The determining unit is further configured to determine the force sensor failure condition based on the first minimum clamping force, the first maximum clamping force, the second minimum clamping force, and the second maximum clamping force; The determination unit is also used to determine that the force sensor is faulty when the current clamping force value detected by the force sensor meets the failure condition of the force sensor.

9. An electronic device, characterized in that, The electronic device includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; A processor, when executing a program stored in memory, implements the steps of the method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the method described in any one of claims 1-7.

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