Brake fade detection method, apparatus, electronic device, and medium

Abstract

The present application relates to the field of vehicle safety control, and relates to a brake decay detection method and device, electronic equipment and medium. The method comprises: in the case of a brake event of a vehicle, obtaining a plurality of brake decay related information of the brake, wherein different brake decay related information comprises different working condition information of the vehicle related to the decay degree of the brake; determining the decay level corresponding to the brake decay related information according to each brake decay related information in the plurality of brake decay related information; determining the decay level of the brake according to the decay level corresponding to each brake decay related information in the plurality of brake decay related information. In this way, the decay degree of the brake can be reasonably detected, and the decay level representing the decay degree of the brake can be obtained, so that the vehicle or the driver can perform various driving safety guarantee work according to the obtained decay level.

Description

Technical Field

[0001] This invention relates to the field of vehicle safety testing, and more particularly to a method, apparatus, electronic device, and medium for detecting brake fade. Background Technology

[0002] Brake fade is caused by a series of physical and chemical changes in the brake discs due to temperature. These changes reduce the coefficient of friction and frictional torque, and can also damage other components of the braking system, ultimately leading to a decrease in vehicle braking performance. Therefore, to ensure vehicle braking safety, it is necessary to detect brake fade to guarantee driving safety. Summary of the Invention

[0003] The purpose of this application is to provide a brake fade detection method, device, electronic device, and medium, so that brake fade can be reasonably detected to ensure driving safety.

[0004] In a first aspect, embodiments of this application provide a brake fade detection method, wherein the brake includes a brake disc, and the method includes:

[0005] In the event of a braking event in a vehicle, various brake fade correlation information is obtained, wherein different brake fade correlation information includes different vehicle operating condition information associated with the degree of brake fade.

[0006] Based on each of the various brake fade association information, determine the fade level corresponding to the brake fade association information;

[0007] The brake's degradation level is determined based on the degradation level corresponding to each of the various brake degradation association information, wherein the brake's degradation level is used to characterize the degree of degradation of the brake.

[0008] In some implementations, determining the degradation level corresponding to each of the multiple brake degradation association information includes:

[0009] When the various brake fade-related information includes the temperature of the brake disc, the first fade level of the brake is determined based on the temperature of the brake disc.

[0010] When the various brake fade-related information includes the wheel-side pressure of each wheel of the vehicle and the status of the anti-lock braking system, the second fade level of the brake is determined based on the wheel-side pressure of each wheel and the status of the anti-lock braking system, wherein the status of the anti-lock braking system is used to characterize whether the anti-lock braking system is in an activated or deactivated state.

[0011] When the various brake fade-related information includes the total braking force of the vehicle, the braking force generated by the brake energy recovery system, and the actual deceleration of the vehicle, the third fade level of the brake is determined based on the total braking force of the vehicle, the braking force generated by the brake energy recovery system, and the actual deceleration of the vehicle.

[0012] When the various brake fade-related information includes the wheel-side pressure of each wheel and the actual total volume of brake fluid in the hydraulic braking system, the fourth fade level of the brake is determined based on the wheel-side pressure of each wheel and the actual total volume.

[0013] In some embodiments, the multiple brake fade correlation information includes the temperature of the brake disc, the wheel-side pressure of each wheel, the status of the anti-lock braking system, the total braking force of the vehicle, the braking force generated by the brake energy recovery system, the actual deceleration of the vehicle, and the actual total volume. Determining the brake fade level based on the fade level corresponding to each of the multiple brake fade correlation information includes:

[0014] The degradation level of the brake is determined based on the first degradation level, the second degradation level, the third degradation level, and the fourth degradation level.

[0015] In some embodiments, determining the first fade level of the brake based on the temperature of the brake disc includes:

[0016] If the temperature of the brake disc exceeds a preset temperature value for a period of time exceeding a preset duration, the first degradation level is determined based on the temperature of the brake disc.

[0017] In some embodiments, determining the second brake fade level based on the wheel-side pressure of each wheel of the vehicle and the state of the anti-lock braking system includes:

[0018] When the wheel-side pressure of each wheel meets the triggering conditions of the anti-lock braking system (ABS) and the ABS is in a non-triggered state, the second fade level is determined based on the wheel-side pressure of each wheel.

[0019] In some implementations, the anti-lock braking system triggering conditions include:

[0020] The average wheel-side pressure of the whole vehicle, the average wheel-side pressure of the front axle, and the average wheel-side pressure of the rear axle, determined based on the wheel-side pressure of each wheel, all reach the wheel lock-up threshold.

[0021] In some embodiments, determining the third brake fade level based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration includes:

[0022] The hydraulic braking force generated by the hydraulic braking system is determined based on the total braking force of the vehicle and the braking force generated by the brake energy recovery system.

[0023] The front axle braking force and rear axle braking force of the vehicle are determined based on the hydraulic braking force.

[0024] The theoretical deceleration of the vehicle is determined based on the front axle braking force and the rear axle braking force;

[0025] The third decay level is determined based on the theoretical deceleration and the actual deceleration.

[0026] In some implementations, determining the third decay level based on the theoretical deceleration and the actual deceleration includes:

[0027] Determine a first ratio between the actual deceleration and the theoretical deceleration;

[0028] The third decline level is determined based on the first ratio.

[0029] In some embodiments, determining the fourth fade level of the brake based on the wheel-side pressure of each wheel and the actual total volume includes:

[0030] The theoretical total volume of brake fluid in the hydraulic braking system is determined based on the theoretical volume of brake fluid corresponding to the wheel-side pressure of each wheel.

[0031] The fourth degradation level is determined based on the theoretical total volume and the actual total volume.

[0032] In some implementations, determining the fourth degradation level based on the theoretical total volume and the actual total volume includes:

[0033] Determine a second ratio between the actual total volume and the theoretical total volume;

[0034] The fourth recession level is determined based on the second ratio.

[0035] In some embodiments, the method further includes:

[0036] If the braking force generated by the regenerative braking system is greater than a preset threshold, the hydraulic braking force generated by the hydraulic braking system is determined based on the total braking force of the vehicle and the braking force generated by the regenerative braking system.

[0037] When the duration during which the hydraulic braking force is less than the locking pressure threshold is greater than a preset duration, the maximum pressure for establishing the hydraulic braking system is controlled to be less than or equal to the preset pressure threshold, wherein the locking pressure threshold is the hydraulic braking force generated by the hydraulic braking system when each wheel locks up.

[0038] In some embodiments, determining the third brake fade level based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration includes:

[0039] When the vehicle's operating conditions meet the detection start conditions, the third fade level of the brake is determined based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration.

[0040] The detection activation conditions include:

[0041] The vehicle speed is greater than a preset speed threshold, and the wheel edge pressure of each wheel is greater than a preset pressure threshold, and the accelerator pedal of the vehicle is not depressed.

[0042] In some embodiments, determining the third brake fade level based on the vehicle's total braking force, the braking force generated by the regenerative braking system, and the vehicle's actual deceleration includes:

[0043] Multiple third fade levels are obtained within a time period during which the braking event of the vehicle occurs, determined by multiple detection cycles, wherein the multiple third fade levels correspond to the multiple detection cycles.

[0044] The third degradation level of the brake is determined based on the plurality of third degradation levels.

[0045] In some embodiments, determining the fourth fade level of the brake based on the wheel-side pressure of each wheel and the actual total volume includes:

[0046] Detect the operating status information of the pressure regulating valve and the air intake control valve of the hydraulic braking system;

[0047] When the operating status information indicates that the pressure regulating valve is open and the intake control valve is closed, the fourth fade level of the brake is determined based on the wheel edge pressure of each wheel and the actual total volume.

[0048] In some embodiments, the method further includes:

[0049] An alarm signal is generated and output based on the brake's degradation level.

[0050] In some embodiments, after generating and outputting an alarm signal based on the brake's degradation level, the method further includes:

[0051] When the brake's degradation level indicates that the brake has not degraded, the degradation level of the brake is monitored within a preset time period.

[0052] If the brake's degradation level indicates that the brake has not degraded within the preset time period, clear all alarm signals.

[0053] Secondly, embodiments of this application provide a brake fade detection device, the brake including a brake disc, the device comprising:

[0054] The associated information acquisition module is used to acquire various brake fade associated information of the brake when a braking event occurs in the vehicle. The different brake fade associated information includes different vehicle operating condition information associated with the degree of brake fade.

[0055] The first module for determining the fade level is used to determine the fade level corresponding to the brake fade association information based on each of the multiple brake fade association information.

[0056] The second module for determining the degradation level is used to determine the degradation level of the brake based on the degradation level corresponding to each of the various brake degradation association information, wherein the degradation level of the brake is used to characterize the degree of degradation of the brake.

[0057] Thirdly, embodiments of this application provide an electronic device, including a processor and a memory, wherein the memory stores a program or instructions that can run on the processor, and when the program or instructions are executed by the processor, they implement the steps of the brake fade detection method provided in the first aspect of embodiments of this application.

[0058] Fourthly, embodiments of this application provide a machine-readable storage medium storing instructions that, when executed by a processor, cause the processor to implement the brake fade detection method provided in the first aspect of embodiments of this application.

[0059] In this embodiment, the degree of brake fade is characterized by the brake fade level. When the vehicle brakes, various brake fade correlation information is acquired. This information includes different vehicle operating condition information associated with the degree of brake fade. A corresponding fade level is determined based on each brake fade correlation information. Finally, all fade levels obtained from the various brake fade correlation information are combined to determine the brake fade level. In this way, the degree of brake fade can be reasonably detected, and a fade level that characterizes the degree of brake fade can be obtained, enabling the vehicle or driver to perform various driving safety measures based on the obtained fade level. Attached Figure Description

[0060] Figure 1 This is a schematic flowchart of the brake fade detection method provided in the embodiments of this application;

[0061] Figure 2 This is a schematic diagram of the brake fade detection device provided in the embodiments of this application;

[0062] Figure 3 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0063] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0064] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0065] The brake fade detection method, device, electronic equipment, and medium provided in this application will be described in detail below with reference to the accompanying drawings and through specific embodiments and application scenarios.

[0066] Please see Figure 1This is a flowchart illustrating the brake fade detection method provided in this application embodiment. The first aspect of this application embodiment provides a brake fade detection method, including the following steps S100-S300:

[0067] Step S100: In the event of a braking event, obtain various brake fade correlation information of the brake, wherein different brake fade correlation information includes different vehicle operating condition information related to the degree of brake fade.

[0068] In a vehicle braking system, the brake is a device used to slow down or stop the vehicle. A brake can include a brake caliper and a brake disc. The brake converts the vehicle's kinetic energy into heat energy through friction, thereby slowing or stopping the vehicle's movement. Therefore, the braking efficiency of the brake is crucial for ensuring braking safety, and overheating of the brake disc can have several negative effects. First, overheating of the brake pads leads to a decrease in braking force, thus increasing braking distance, stopping time, and the risk of collision. Second, overheating makes the friction material unstable, causing brake fade, which causes the brake disc to lose stable friction during braking, resulting in decreased braking performance. Furthermore, overheating of the brake disc can cause deformation and cracking, further damaging the braking system. This can lead not only to brake failure but also damage other related components. Overheating of the brake disc can also damage other components of the braking system, such as the brake caliper and brake fluid, resulting in an overall reduction in braking performance.

[0069] Therefore, it is necessary to test the degree of brake fade caused by brake disc temperature in order to determine whether the brake fade will affect the safety of vehicle braking.

[0070] Brake fade manifests in multiple aspects during vehicle braking. Therefore, when a braking event occurs, the processor acquires various vehicle operating condition information related to the degree of brake fade, such as brake disc temperature, wheel edge pressure of each wheel, and total braking force. These are used as various brake fade-related information to subsequently determine the brake fade level. Those skilled in the art will understand that the aforementioned processor can be the vehicle's electronic control unit (ECU).

[0071] Step S200: Determine the degradation level corresponding to each brake degradation association information in the various brake degradation association information.

[0072] After obtaining multiple brake fade correlation information, the fade level corresponding to each brake fade correlation information is determined based on each brake fade correlation information. This fade level characterizes the degree of brake fade reflected by each brake fade correlation information.

[0073] For example, the brake fade-related information is the temperature of the brake disc. The corresponding fade level obtained by determining the temperature of the brake disc represents the degree of brake fade reflected by the temperature of the brake disc.

[0074] Step S300: Determine the brake's degradation level based on the degradation level corresponding to each brake degradation association information in the multiple brake degradation association information, wherein the brake's degradation level is used to characterize the degree of brake degradation.

[0075] In step S200, multiple degradation levels corresponding to each brake degradation association information are obtained through various brake degradation association information. The multiple degradation levels are comprehensively analyzed to determine the final brake degradation level. The processor can know the current degree of brake degradation based on the determined brake degradation level.

[0076] For example, when determining the brake's degradation level through multiple degradation levels corresponding to various brake degradation association information, the degradation level that represents the greatest and most severe degree of brake degradation among the multiple degradation levels can be taken as the brake's degradation level.

[0077] Through steps S100-S300, the degree of brake fade is characterized by the brake fade level. When the vehicle brakes, various brake fade-related information is acquired. This information includes different vehicle operating condition information associated with the degree of brake fade. The corresponding fade level is determined based on each brake fade-related information. Finally, all fade levels obtained from the various brake fade-related information are combined to determine the brake fade level. In this way, the degree of brake fade can be reasonably detected, and a fade level that characterizes the degree of brake fade can be obtained, enabling the vehicle or driver to perform various driving safety measures based on the obtained fade level.

[0078] In some implementations, determining the degradation level corresponding to each brake degradation association information based on multiple brake degradation association information may include:

[0079] In cases where multiple brake fade-related information includes the temperature of the brake disc, the first fade level of the brake is determined based on the temperature of the brake disc.

[0080] Given multiple brake fade-related information, including the wheel-side pressure of each wheel of the vehicle and the status of the anti-lock braking system (ABS), the second fade level of the brake is determined based on the wheel-side pressure of each wheel and the status of the ABS. The status of the ABS is used to characterize whether the ABS is in an activated or deactivated state.

[0081] Given multiple brake fade-related information, including the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration, the third brake fade level is determined based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration.

[0082] Given multiple brake fade-related information, including the wheel-side pressure of each wheel and the actual total volume of brake fluid in the hydraulic braking system, the fourth fade level of the brake is determined based on the wheel-side pressure of each wheel and the actual total volume.

[0083] The composition of various brake fade correlation information can vary. The temperature of the brake disc is the most direct indicator of whether the brake will fade due to overheating of the brake disc. Therefore, when the brake disc temperature is included in the various brake fade correlation information, a fade level can be determined by the temperature of the brake disc, which is denoted as the first fade level.

[0084] The wheel-side pressure of each wheel refers to the vertical pressure exerted on the part of the wheel in contact with the ground. During vehicle braking, the friction between the wheel and the ground determines the maximum braking force the vehicle can apply. Since friction is determined by the wheel-side pressure and the coefficient of friction, the greater the wheel-side pressure, the greater the friction. Therefore, the wheel-side pressure of each wheel is particularly important for evaluating vehicle braking performance.

[0085] For example, without considering vehicle manufacturing costs, each wheel can be equipped with a wheel edge pressure sensor to obtain the wheel edge pressure; the wheel edge pressure of each wheel can also be estimated by a processor through the calibrated pedal travel.

[0086] The Anti-lock Braking System (ABS) is a safety technology used in vehicle braking systems. Its main function is to prevent wheel lock-up during emergency braking or braking on slippery surfaces, thereby maintaining vehicle control and stability. ABS automatically adjusts braking force to prevent the wheels from losing traction with the ground, thus avoiding loss of control or skidding. If the ABS fails to trigger under high wheel-side pressure, it indicates potential brake fade, resulting in insufficient braking effectiveness.

[0087] Given multiple brake fade-related information, including the wheel-side pressure of each wheel of the vehicle and the status of the anti-lock braking system (ABS) (whether the ABS has been triggered or not), a fade level can be determined by the wheel-side pressure of each wheel and the status of the ABS, which is denoted as the second fade level.

[0088] The regenerative braking system converts the vehicle's kinetic energy into braking force during braking events, thus assisting in braking. The braking force generated by the regenerative braking system can be calculated by detecting the regenerative torque generated by the system during braking; the regenerative torque is the reverse torque used to decelerate the vehicle. The total braking force of the vehicle refers to the sum of all braking forces acting on the wheels during braking. It includes the hydraulic braking force generated by the hydraulic braking system and the braking force generated by the regenerative braking system. The total braking force can be calculated by detecting the travel of the brake pedal using a travel sensor connected to the brake pedal. The actual deceleration of the vehicle is the actual deceleration of the vehicle during braking or deceleration, which can be indirectly calculated from the speed signal generated by the vehicle's speed sensor.

[0089] Given various brake fade-related information, including the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration, a fade level can be determined by the wheel-side pressure of each wheel and the status of the anti-lock braking system, denoted as the third fade level.

[0090] The actual total volume of brake fluid in a hydraulic braking system is the volume of brake fluid used for hydraulic braking in the vehicle's hydraulic braking system. This actual total volume can be obtained by measuring the fluid level sensor installed in the hydraulic brake master cylinder.

[0091] Given various brake fade-related information, including the wheel-side pressure of each wheel and the actual total volume of brake fluid in the hydraulic braking system, a fade level can be determined by the wheel-side pressure of each wheel and the status of the anti-lock braking system, denoted as the fourth fade level.

[0092] In some implementations, the various brake fade correlation information may include brake disc temperature, wheel-side pressure of each wheel, status of the anti-lock braking system, total braking force of the vehicle, braking force generated by the brake energy recovery system, actual deceleration of the vehicle, and actual total volume. Based on the fade level corresponding to each brake fade correlation information in the various brake fade correlation information, the brake fade level is determined, which may include:

[0093] The brake's degradation level is determined based on the first degradation level, the second degradation level, the third degradation level, and the fourth degradation level.

[0094] If the multiple brake fade correlation information includes the aforementioned brake fade correlation information used to determine the first fade level, second fade level, third fade level, and fourth fade level, that is, including the brake disc temperature, wheel edge pressure of each wheel, status of the anti-lock braking system, total braking force of the vehicle, braking force generated by the brake energy recovery system, actual deceleration of the vehicle, and actual total volume, then after obtaining the first fade level, second fade level, third fade level, and fourth fade level, the processor will perform a comprehensive analysis of the first fade level, second fade level, third fade level, and fourth fade level to determine the brake fade level.

[0095] For example, when determining the brake's degradation level through the first degradation level, the second degradation level, the third degradation level, and the fourth degradation level, the degradation level that represents the greatest and most severe degradation of the brake can be taken as the brake's degradation level.

[0096] Those skilled in the art will understand that during a braking event, the driver may perform multiple braking actions. When the processor detects the brake fade level, it needs to determine whether the braking event has completed effective braking. For example, when the total braking force of the vehicle or the wheel edge pressure of each wheel reaches a certain preset value and is at the rising edge, it can be determined that the vehicle is performing effective braking, and the processor can then begin to detect the brake fade level.

[0097] In some implementations, determining the first brake fade level based on the temperature of the brake disc may include:

[0098] If the brake disc temperature exceeds the preset temperature value for a period of time, the first fade level is determined based on the brake disc temperature.

[0099] To prevent excessive fluctuations in the determination of the first brake fade level—that is, to prevent immediate detection and output of the first fade level as soon as the brake disc temperature slightly overheats, which would lead to an inaccurate and unscientific determination of the first fade level—the processor can impose conditional restrictions on the detection and determination of the first fade level. The first fade level will only be determined based on the brake disc temperature if the brake disc temperature exceeds a preset value for a preset duration; in other words, only if the brake disc overheats for a preset duration.

[0100] In some implementations, determining the second brake fade level based on the wheel-side pressure of each wheel of the vehicle and the status of the anti-lock braking system may include:

[0101] When the wheel-side pressure of each wheel meets the triggering conditions of the anti-lock braking system (ABS) and the ABS is in an untriggered state, the second fade level is determined based on the wheel-side pressure of each wheel.

[0102] If the anti-lock braking system (ABS) fails to activate even when the wheel-end pressures of all wheels meet the activation conditions, it indicates potential brake fade and insufficient braking performance. In this case, the processor determines a second fade level based on the wheel-end pressures of each wheel. For example, the second fade level can be determined based on the difference between the average wheel-end pressure of each wheel and the wheel lock-up threshold.

[0103] In some implementations, the anti-lock braking system triggering conditions may include:

[0104] The average wheel-side pressure of the whole vehicle, the average wheel-side pressure of the front axle, and the average wheel-side pressure of the rear axle, all determined based on the wheel-side pressure of each wheel, have reached the wheel lock-up threshold.

[0105] The processor first determines the average wheel-side pressure of the entire vehicle based on the wheel-side pressure of each wheel, i.e., the average value of the wheel-side pressure of each wheel. Then, it calculates the average wheel-side pressure of the two front wheels as the average front axle wheel-side pressure, and the average wheel-side pressure of the two rear wheels as the average rear axle wheel-side pressure. When the average wheel-side pressure of the entire vehicle, the average wheel-side pressure of each axle, and the average wheel-side pressure of the rear axle all reach the wheel lock-up threshold, the processor considers that the wheel-side pressure of each wheel meets the triggering conditions of the anti-lock braking system.

[0106] In some implementations, the third brake fade level is determined based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration, including:

[0107] The hydraulic braking force generated by the hydraulic braking system is determined based on the vehicle's total braking force and the braking force generated by the brake energy recovery system.

[0108] The front and rear axle braking forces of the vehicle are determined based on the hydraulic braking force.

[0109] The theoretical deceleration of the vehicle is determined based on the braking force of the front axle and the braking force of the rear axle;

[0110] The third decay level is determined based on the theoretical deceleration and the actual deceleration.

[0111] The third level of deceleration is determined based on the vehicle's theoretical deceleration and actual deceleration. The processor first subtracts the braking force generated by the regenerative braking system from the vehicle's total braking force to obtain the hydraulic braking force generated by the hydraulic braking system.

[0112] The processor then determines the front and rear axle braking forces of the vehicle based on the hydraulic braking force.

[0113] For example, the processor can determine the braking force of the front axle and the rear axle by using the pre-set front and rear axle distribution ratio of the proportional valve in the hydraulic braking system; the processor can also determine the front axle braking force and the rear axle braking force according to a specific pressure calculation model determined by vehicle design parameters and experimental data, input the hydraulic braking force into the model, and directly obtain the front axle braking force and the rear axle braking force determined by the model by converting the hydraulic braking force.

[0114] After determining the front axle braking force and the rear axle braking force, the processor calculates and determines the vehicle's theoretical deceleration based on these forces.

[0115] For example, the theoretical deceleration of a vehicle can be obtained by dividing the sum of the front axle braking force and the rear axle braking force by the mass of the vehicle.

[0116] If the actual deceleration does not reach the theoretical deceleration, the braking efficiency of the brake may decline. When the actual deceleration does not reach the theoretical deceleration, the greater the gap between the actual deceleration and the theoretical deceleration, the greater the degree of brake decline.

[0117] Finally, the processor determines the third decay level based on the obtained theoretical deceleration and the actual deceleration.

[0118] In some implementations, the third decay level is determined based on the theoretical deceleration and the actual deceleration, including:

[0119] Determine the first ratio between the actual deceleration and the theoretical deceleration;

[0120] The third recession level is determined based on the first ratio.

[0121] In the specific process of determining the third decay level based on the actual deceleration and the theoretical deceleration, the processor first determines the first ratio between the actual deceleration and the theoretical deceleration, and then determines the third decay level based on the first ratio.

[0122] For example, since a smaller first ratio indicates a greater degree of brake degradation, the processor can determine the third degradation level by judging whether the first ratio falls within the range of ratios corresponding to a certain degradation level. For instance, degradation levels are divided into 0, 1, and 2 according to the degree of degradation they represent, from largest to smallest. The ratio range corresponding to degradation level 1 is A. If the first ratio falls within the ratio range A, the third degradation level can be determined to be 1.

[0123] In some implementations, determining the fourth brake fade level based on the wheel-side pressure and actual total volume of each wheel may include:

[0124] The theoretical total volume of brake fluid in the hydraulic braking system is determined based on the theoretical volume of brake fluid corresponding to the wheel-side pressure of each wheel.

[0125] The fourth recession level is determined based on the theoretical total volume and the actual total volume.

[0126] The fourth degradation level is determined based on the theoretical and actual total volume of the vehicle's brake fluid. The processor first determines the theoretical total volume of the vehicle's brake fluid, i.e., the theoretical total volume of the brake fluid in the hydraulic braking system, based on the theoretical volume of brake fluid corresponding to the wheel-side pressure of each wheel.

[0127] For example, the processor can determine the theoretical total volume based on a pre-stored pressure-volume (PV) curve, which represents the required brake fluid volume under different wheel-side pressures. The processor adds up the brake fluid volumes corresponding to the wheel-side pressures of each wheel in the pressure-volume curve to obtain the theoretical total volume of brake fluid required for the entire vehicle.

[0128] If the actual total volume does not reach the theoretical total volume, the braking performance of the brake may decline. When the actual total volume does not reach the theoretical total volume, the greater the difference between the actual total volume and the theoretical total volume, the greater the degree of brake decline.

[0129] Finally, the processor determines the fourth degradation level based on the theoretical total volume and the actual total volume.

[0130] In some implementations, determining the fourth degradation level based on the theoretical total volume and the actual total volume may include:

[0131] Determine the second ratio between the actual total volume and the theoretical total volume;

[0132] The fourth recession level is determined based on the second ratio.

[0133] In the specific process of determining the fourth decay level based on the actual total volume and the theoretical total volume, the processor first determines the second ratio between the actual total volume and the theoretical total volume, and then determines the fourth decay level based on the second ratio.

[0134] For example, since a smaller second ratio indicates a greater degree of brake degradation, the processor can determine the fourth degradation level by judging whether the second ratio falls within the range corresponding to a certain degradation level. For instance, degradation levels are divided into 0, 1, and 2 according to the degree of degradation they represent, from largest to smallest. The ratio range corresponding to degradation level 1 is B. If the second ratio is within the ratio range B, the fourth degradation level can be determined to be 1.

[0135] In some implementations, the method may further include:

[0136] When the braking force generated by the regenerative braking system is greater than a preset threshold, the hydraulic braking force generated by the hydraulic braking system is determined based on the vehicle's total braking force and the braking force generated by the regenerative braking system.

[0137] When the duration during which the hydraulic braking force is less than the locking pressure threshold is greater than a preset duration, the maximum pressure for establishing the hydraulic braking system is less than or equal to the preset pressure threshold, where the locking pressure threshold is the hydraulic braking force generated by the hydraulic braking system when each wheel locks up.

[0138] When a vehicle brakes, the regenerative braking system converts the vehicle's kinetic energy into braking force, thus assisting in braking. The braking force generated by the regenerative braking system can be manifested as the regenerative torque generated during braking, which is the reverse torque that causes the vehicle to decelerate.

[0139] When the braking force generated by the regenerative braking system exceeds a preset threshold, or when the regenerative torque generated by the regenerative braking system exceeds a specific torque, it means that the regenerative braking system is actively participating in the braking process and providing significant braking force. In other words, the hydraulic braking force provided by the hydraulic braking system is insufficient, meaning that the brake fade has affected the braking efficiency of the hydraulic braking system.

[0140] Therefore, under the above circumstances, the processor first uses the total braking force of the vehicle to subtract the braking force generated by the braking energy recovery system to determine the hydraulic braking force generated by the hydraulic braking system. If the duration for which the hydraulic braking force cannot reach the locking pressure threshold exceeds the preset duration (the locking pressure threshold is the hydraulic braking force generated by the hydraulic braking system when each wheel locks up), it indicates that the hydraulic braking force of the vehicle needs to be compensated to maintain braking performance. At this time, the processor will control the hydraulic braking system to increase the maximum pressure that can be established, that is, increase the pressure of the hydraulic braking master cylinder.

[0141] However, increasing the maximum pressure that the hydraulic braking system can build up will cause the temperature of the hydraulic braking system to continue to rise, leading to more severe degradation of the hydraulic braking system and the brake. Therefore, after determining that the maximum pressure that the hydraulic braking system can build up needs to be increased to compensate for the lack of hydraulic braking force, in order to prevent the degradation of the hydraulic braking system and the brake from becoming more severe, the processor limits the maximum pressure that the hydraulic braking system can build up, controlling the maximum pressure that the hydraulic braking system can build up to not exceed a preset pressure threshold.

[0142] In some implementations, determining the third brake fade level based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration may include:

[0143] When the vehicle's operating conditions meet the detection start conditions, the third brake fade level is determined based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration.

[0144] The detection activation conditions include:

[0145] The vehicle speed is greater than the preset speed threshold, and the wheel pressure of each wheel is greater than the preset pressure threshold, while the accelerator pedal is not depressed.

[0146] The processor can also set detection start conditions for the third decay level in order to accurately detect the third decay level. Only when the vehicle's operating conditions meet the detection start conditions will the processor determine the third decay level of the brake based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration.

[0147] At low speeds, the braking system may operate unstablely, and the acquired parameter data is easily affected by noise and other factors, leading to inaccurate test results. At high speeds, however, the vehicle's dynamic behavior is more pronounced, and braking performance is more clearly reflected, ensuring the accuracy and reliability of the third-level fade detection. Therefore, the detection initiation condition can include: the vehicle speed exceeding a preset speed threshold.

[0148] To ensure that the vehicle's braking system is indeed working, i.e., that the vehicle is indeed braking, the detection start conditions may also include: and the wheel edge pressure of each wheel is greater than a preset pressure threshold.

[0149] To ensure that the detection of the third degradation level is performed while the vehicle is decelerating, rather than while the driver is simultaneously pressing the accelerator pedal, the detection initiation condition may also include: the accelerator pedal being unpressed.

[0150] In some implementations, the third brake fade level is determined based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration, including:

[0151] Multiple third decay levels are obtained from multiple detection cycles during the time period when the vehicle braking event occurs, and the multiple third decay levels correspond to multiple detection cycles.

[0152] The third degradation level of the brake is determined based on multiple third degradation levels.

[0153] During the time period in which the braking event occurs, there may be multiple detection cycles for detecting the third decay level. Each detection cycle detects and obtains a third decay level. The processor performs comprehensive analysis on the multiple third decay levels obtained from the multiple detection cycles to determine the third decay level of the brake.

[0154] For example, the time period during which the braking event occurs includes four detection cycles. The third degradation level is divided into 0, 1, and 2 according to the degree of degradation it represents, from largest to smallest. The third degradation level detected in the first detection cycle is 0, and the processor temporarily records the third degradation level of the brake as 0. The third degradation level detected in the second detection cycle is 1, and the processor temporarily records the third degradation level of the brake as 1. The third degradation level detected in the third detection cycle is 2, and the processor temporarily records the third degradation level of the brake as 2. The third degradation level detected in the fourth detection cycle is 1. Since the detection of the third degradation level is unidirectionally increasing and will not degrade over multiple detection cycles, the processor still records the third degradation level of the brake as 2. That is, among multiple third degradation levels, the third degradation level that represents the largest degree of brake degradation is determined as the final determined third degradation level of the brake.

[0155] In some implementations, the fourth brake fade level is determined based on the wheel-side pressure of each wheel and the actual total volume, including:

[0156] Multiple fourth decay levels are obtained from multiple detection cycles during the time period when the vehicle braking event occurs, and the multiple fourth decay levels correspond to multiple detection cycles.

[0157] The fourth decay level of the brake is determined based on multiple fourth decay levels.

[0158] The determination of the fourth fade level of the brake can also be similar to the determination process of the third fade level in the above embodiments, using multiple fourth fade levels corresponding to multiple detection cycles to determine the final fourth fade level of the brake.

[0159] In some implementations, determining the fourth brake fade level based on the wheel-side pressure and actual total volume of each wheel may include:

[0160] Detect the working status information of the pressure regulating valve and the air intake control valve of the hydraulic braking system;

[0161] With the working status information indicating that the pressure regulating valve is open and the intake control valve is closed, the fourth fade level of the brake is determined based on the wheel edge pressure of each wheel and the actual total volume.

[0162] The processor can also set detection start conditions for the fourth fade level in order to accurately detect the fourth fade level. Only when the hydraulic braking system pressure regulating valve is open and the air intake control valve is closed (that is, the brake fluid can flow freely and prevents external air from entering the hydraulic braking system) will the processor determine the fourth fade level of the brake based on the wheel edge pressure of each wheel and the actual total volume.

[0163] In some implementations, the method may further include:

[0164] An alarm signal is generated and output based on the brake's degradation level.

[0165] The processor can generate and output a corresponding alarm signal based on the determined brake fade level, prompting the driver to eliminate brake fade as soon as possible.

[0166] In some implementations, after generating and outputting an alarm signal based on the brake's degradation level, the method further includes:

[0167] The brake degradation level is characterized by the brake degradation level being determined within a preset time period when the brake has not degraded.

[0168] If the brake's degradation level indicates that the brake has not degraded within the preset time period, clear all alarm signals.

[0169] If the brake fade has been eliminated and the brake performance has returned to normal, the processor will reset the brake fade level and clear all alarm signals.

[0170] Specifically, if the obtained brake degradation level indicates that the brake has not degraded, the processor can start a timer to keep track of the time. If, within a preset time period, the obtained brake degradation level still indicates that the brake has not degraded, the processor can determine that the brake's thermal degradation has been eliminated and the brake's braking performance has returned to normal. The processor will then clear all alarm signals and reset the brake's degradation level to the degradation level that indicates that the brake has not degraded.

[0171] Please see Figure 2 This is a schematic diagram of the brake fade detection device provided in the embodiments of this application. A second aspect of this application provides a brake fade detection device 1000, the brake including a brake disc, and the device 1000 including:

[0172] The associated information acquisition module 1001 is used to acquire various brake fade associated information of the brake when a braking event occurs in the vehicle. Among them, different brake fade associated information includes different vehicle operating condition information associated with the degree of brake fade.

[0173] The first module 1002 for determining the fade level is used to determine the fade level corresponding to the brake fade association information based on the various brake fade association information.

[0174] The second module 1003 for determining the degradation level is used to determine the degradation level of the brake based on the degradation level corresponding to each brake degradation association information in multiple brake degradation association information, wherein the degradation level of the brake is used to characterize the degree of degradation of the brake.

[0175] The brake fade detection device 1000 provided in the second aspect of the embodiments of this application can realize the various processes implemented in the above method embodiments and achieve the same beneficial effects. To avoid repetition, it will not be described again here.

[0176] Please see Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. A third aspect of this application provides an electronic device 2000, including a processor 2001 and a memory 2002. The memory 2002 stores machine-executable instructions that can be executed by the processor 2001. The processor 2001 can execute the machine-executable instructions to implement the above-mentioned brake fade detection method.

[0177] A fourth aspect of this application provides a machine-readable storage medium storing instructions that, when executed by a processor, cause the processor to implement the aforementioned brake fade detection method.

[0178] In one embodiment of this application, a computer program product is also provided, including a computer program that, when executed by a processor, implements the brake fade detection method according to the above embodiments.

[0179] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied 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.

[0180] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. 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... Figure 1 One or more processes and / or boxes Figure 1 The 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 operate 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 functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus 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.

[0181] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0182] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0183] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0184] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0185] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

[0186] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for detecting brake fade, wherein the brake includes a brake disc, characterized in that, The method includes: In the event of a braking event in a vehicle, various brake fade correlation information is obtained, wherein different brake fade correlation information includes different vehicle operating condition information associated with the degree of brake fade. Based on each of the various brake fade association information, determine the fade level corresponding to the brake fade association information; The brake's degradation level is determined based on the degradation level corresponding to each of the various brake degradation association information, wherein the brake's degradation level is used to characterize the degree of degradation of the brake. The step of determining the degradation level corresponding to each of the multiple brake degradation association information includes: When the various brake fade-related information includes the temperature of the brake disc, the first fade level of the brake is determined based on the temperature of the brake disc. When the various brake fade-related information includes the wheel-side pressure of each wheel of the vehicle and the status of the anti-lock braking system, the second fade level of the brake is determined based on the wheel-side pressure of each wheel and the status of the anti-lock braking system, wherein the status of the anti-lock braking system is used to characterize whether the anti-lock braking system is in an activated or deactivated state. When the various brake fade-related information includes the total braking force of the vehicle, the braking force generated by the brake energy recovery system, and the actual deceleration of the vehicle, the third fade level of the brake is determined based on the total braking force of the vehicle, the braking force generated by the brake energy recovery system, and the actual deceleration of the vehicle. When the various brake fade correlation information includes the wheel-side pressure of each wheel and the actual total volume of brake fluid in the hydraulic braking system, the fourth fade level of the brake is determined based on the wheel-side pressure of each wheel and the actual total volume. If the braking force generated by the regenerative braking system is greater than a preset threshold, the hydraulic braking force generated by the hydraulic braking system is determined based on the total braking force of the vehicle and the braking force generated by the regenerative braking system. When the duration during which the hydraulic braking force is less than the locking pressure threshold is greater than a preset duration, the maximum pressure for establishing the hydraulic braking system is controlled to be less than or equal to the preset pressure threshold, wherein the locking pressure threshold is the hydraulic braking force generated by the hydraulic braking system when each wheel locks up.

2. The method according to claim 1, characterized in that, The various brake fade correlation information includes the temperature of the brake disc, the wheel-side pressure of each wheel, the status of the anti-lock braking system, the total braking force of the vehicle, the braking force generated by the brake energy recovery system, the actual deceleration of the vehicle, and the actual total volume. Determining the brake fade level based on the fade level corresponding to each of the various brake fade correlation information includes: The degradation level of the brake is determined based on the first degradation level, the second degradation level, the third degradation level, and the fourth degradation level.

3. The method according to claim 1, characterized in that, Determining the first fade level of the brake based on the temperature of the brake disc includes: If the temperature of the brake disc exceeds a preset temperature value for a period of time exceeding a preset duration, the first degradation level is determined based on the temperature of the brake disc.

4. The method according to claim 1, characterized in that, Determining the second brake fade level based on the wheel-side pressure of each wheel of the vehicle and the state of the anti-lock braking system includes: When the wheel-side pressure of each wheel meets the triggering conditions of the anti-lock braking system (ABS) and the ABS is in a non-triggered state, the second fade level is determined based on the wheel-side pressure of each wheel.

5. The method according to claim 4, characterized in that, The triggering conditions for the anti-lock braking system include: The average wheel-side pressure of the whole vehicle, the average wheel-side pressure of the front axle, and the average wheel-side pressure of the rear axle, determined based on the wheel-side pressure of each wheel, all reach the wheel lock-up threshold.

6. The method according to claim 1, characterized in that, Determining the third brake fade level based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration includes: The hydraulic braking force generated by the hydraulic braking system is determined based on the total braking force of the vehicle and the braking force generated by the brake energy recovery system. The front axle braking force and rear axle braking force of the vehicle are determined based on the hydraulic braking force. The theoretical deceleration of the vehicle is determined based on the front axle braking force and the rear axle braking force; The third decay level is determined based on the theoretical deceleration and the actual deceleration.

7. The method according to claim 6, characterized in that, Determining the third decay level based on the theoretical deceleration and the actual deceleration includes: Determine a first ratio between the actual deceleration and the theoretical deceleration; The third decline level is determined based on the first ratio.

8. The method according to claim 1, characterized in that, Determining the fourth brake fade level based on the wheel-side pressure of each wheel and the actual total volume includes: The theoretical total volume of brake fluid in the hydraulic braking system is determined based on the theoretical volume of brake fluid corresponding to the wheel-side pressure of each wheel. The fourth degradation level is determined based on the theoretical total volume and the actual total volume.

9. The method according to claim 8, characterized in that, Determining the fourth degradation level based on the theoretical total volume and the actual total volume includes: Determine a second ratio between the actual total volume and the theoretical total volume; The fourth recession level is determined based on the second ratio.

10. The method according to claim 1, characterized in that, Determining the third brake fade level based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration includes: When the vehicle's operating conditions meet the detection start conditions, the third fade level of the brake is determined based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration. The detection activation conditions include: The vehicle speed is greater than a preset speed threshold, and the wheel edge pressure of each wheel is greater than a preset pressure threshold, and the accelerator pedal of the vehicle is not depressed.

11. The method according to claim 1, characterized in that, Determining the third brake fade level based on the vehicle's total braking force, the braking force generated by the brake energy recovery system, and the vehicle's actual deceleration includes: Multiple third fade levels are obtained within a time period during which the braking event of the vehicle occurs, determined by multiple detection cycles, wherein the multiple third fade levels correspond to the multiple detection cycles. The third degradation level of the brake is determined based on the plurality of third degradation levels.

12. The method according to claim 1, characterized in that, Determining the fourth brake fade level based on the wheel-side pressure of each wheel and the actual total volume includes: Detect the operating status information of the pressure regulating valve and the air intake control valve of the hydraulic braking system; When the operating status information indicates that the pressure regulating valve is open and the intake control valve is closed, the fourth fade level of the brake is determined based on the wheel edge pressure of each wheel and the actual total volume.

13. The method according to claim 1, characterized in that, The method further includes: An alarm signal is generated and output based on the brake's degradation level.

14. The method according to claim 13, characterized in that, After generating and outputting an alarm signal based on the brake's degradation level, the method further includes: When the brake's degradation level indicates that the brake has not degraded, the degradation level of the brake is monitored within a preset time period. If the brake's degradation level indicates that the brake has not degraded within the preset time period, clear all alarm signals.

15. A brake fade detection device, the brake comprising a brake disc, characterized in that, The device includes: The associated information acquisition module is used to acquire various brake fade associated information of the brake when a braking event occurs in the vehicle. The different brake fade associated information includes different vehicle operating condition information associated with the degree of brake fade. The first module for determining the fade level is used to determine the fade level corresponding to the brake fade association information based on each of the multiple brake fade association information. The second module for determining the degradation level is used to determine the degradation level of the brake based on the degradation level corresponding to each of the multiple brake degradation association information, wherein the degradation level of the brake is used to characterize the degree of degradation of the brake. The step of determining the degradation level corresponding to each of the multiple brake degradation association information includes: When the various brake fade-related information includes the temperature of the brake disc, the first fade level of the brake is determined based on the temperature of the brake disc. When the various brake fade-related information includes the wheel-side pressure of each wheel of the vehicle and the status of the anti-lock braking system, the second fade level of the brake is determined based on the wheel-side pressure of each wheel and the status of the anti-lock braking system, wherein the status of the anti-lock braking system is used to characterize whether the anti-lock braking system is in an activated or deactivated state. When the various brake fade-related information includes the total braking force of the vehicle, the braking force generated by the brake energy recovery system, and the actual deceleration of the vehicle, the third fade level of the brake is determined based on the total braking force of the vehicle, the braking force generated by the brake energy recovery system, and the actual deceleration of the vehicle. When the various brake fade correlation information includes the wheel-side pressure of each wheel and the actual total volume of brake fluid in the hydraulic braking system, the fourth fade level of the brake is determined based on the wheel-side pressure of each wheel and the actual total volume. If the braking force generated by the regenerative braking system is greater than a preset threshold, the hydraulic braking force generated by the hydraulic braking system is determined based on the total braking force of the vehicle and the braking force generated by the regenerative braking system. When the duration during which the hydraulic braking force is less than the locking pressure threshold is greater than a preset duration, the maximum pressure for establishing the hydraulic braking system is controlled to be less than or equal to the preset pressure threshold, wherein the locking pressure threshold is the hydraulic braking force generated by the hydraulic braking system when each wheel locks up.

16. An electronic device, characterized in that, It includes a processor and a memory, the memory storing a program or instructions that can run on the processor, the program or instructions being executed by the processor to implement the steps of the brake fade detection method as described in any one of claims 1-14.

17. A machine-readable storage medium, characterized in that, The machine-readable storage medium stores instructions that, when executed by a processor, cause the processor to implement the brake fade detection method according to any one of claims 1-14.

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