Brake fluid leakage detection method, vehicle controller, and vehicle

Abstract

A brake fluid leakage detection method, a vehicle controller, and a vehicle. The brake fluid leakage detection method comprises: during the process of increasing a first actual pressure of a servo cylinder to a target pressure, when the first actual pressure reaches a preset pressure, acquiring a first hydraulic volume of the servo cylinder, and recording a first moment; during the process of gradually decreasing a second actual pressure of the servo cylinder, when the second actual pressure drops back to the preset pressure, acquiring a second hydraulic volume of the servo cylinder, and recording a second moment; presetting a required fluid volume for system hysteresis when a vehicle leaves the factory; and calculating the volume of leaked brake fluid in an integrated brake control system on the basis of the first hydraulic volume, the second hydraulic volume, and the required fluid volume for system hysteresis, then calculating the time for brake fluid leakage on the basis of the first moment and the second moment, thereby obtaining a first brake fluid leakage amount.

Description

Brake fluid leakage detection method, vehicle controller and vehicle TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicles, in particular to a brake fluid leakage detection method, a vehicle controller and a vehicle. BACKGROUND

[0002] At present, the brake system of a passenger vehicle is mainly a hydraulic brake system, which transmits braking force through a hydraulic circuit. Since the brake system contains components such as brakes, brake hoses, brake hard pipes, joints and integrated brake control assemblies, there is a risk of leakage during use if the sealing is not good, which may result in soft braking or even brake failure, affecting braking safety. For a new type of brake-by-wire hydraulic brake system, brake safety is particularly important.

[0003] In the prior art, the integrated brake control system pre-stores preset pressures corresponding to different depths at which a brake pedal is depressed. When a driver depresses the brake pedal to control the vehicle to brake, the corresponding preset pressure is retrieved according to the depth at which the brake pedal is depressed, the actual measured pressure of a servo cylinder is measured, and the actual measured pressure and the preset pressure are compared. If the actual measured pressure is lower than the preset pressure, it is proved that brake fluid leakage occurs. However, the above leakage detection method cannot accurately calculate the amount of brake fluid leakage.

[0004] SUMMARY

[0005] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application provides a brake fluid leakage detection method, which can accurately calculate the amount of brake fluid leakage and ensure the safe operation of the brake system of a vehicle.

[0006] The present application also provides a vehicle controller and a vehicle comprising the brake fluid leakage detection method.

[0007] According to the brake fluid leakage detection method of the first aspect of the present application, the method is applied to a vehicle having an integrated brake control system, the integrated brake control system having a servo cylinder and a brake pedal, and the detection method comprises:

[0008] When the brake pedal is depressed, a first actual pressure of the servo cylinder is obtained;

[0009] When the first actual pressure rises to a preset pressure, a first hydraulic volume of the servo cylinder and a first time are obtained;

[0010] When the brake pedal is released, a second actual pressure of the servo cylinder is obtained;

[0011] When the second actual pressure decreases to the preset pressure, a second hydraulic volume of the servo cylinder and a second time are obtained;

[0012] According to the first hydraulic volume, the second hydraulic volume, the first time, the second time, and a system hysteresis required liquid volume, a first brake fluid leakage amount is obtained, the system hysteresis required liquid volume is obtained from preset data of the vehicle, and the system hysteresis required liquid volume is used to represent a volume of brake fluid output by the servo cylinder when the pressure of the servo cylinder reaches the preset pressure.

[0013] The brake fluid leakage detection method according to the embodiments of the present application has at least the following beneficial effects: when the driver steps on the brake pedal to control the integrated brake control system to brake the vehicle, the first actual pressure of the servo cylinder is obtained, the depth at which the brake pedal is stepped on determines the target pressure of the servo cylinder, in the process of the first actual pressure of the servo cylinder rising to the target pressure, when the first actual pressure reaches the preset pressure, the first hydraulic volume of the servo cylinder is obtained, and the first time is recorded, and then the first actual pressure gradually rises to the target pressure; after the driver releases the brake pedal, the second actual pressure of the servo cylinder gradually decreases, in the process of the second actual pressure of the servo cylinder gradually decreasing, when the second actual pressure falls back to the preset pressure, the second hydraulic volume of the servo cylinder is obtained, and the second time is recorded; the system hysteresis required liquid volume is preset when the vehicle is shipped, when the pressure of the servo cylinder is equal to the preset pressure, the volume of brake fluid pumped out of the servo cylinder of the integrated brake control system to the brake is the system hysteresis required liquid volume; according to the first hydraulic volume, the second hydraulic volume, and the system hysteresis required liquid volume, the volume of leaked brake fluid in the integrated brake control system can be calculated, and then the time of the leaked brake fluid is calculated according to the first time and the second time, and thus the first brake fluid leakage amount is obtained, which can accurately calculate the brake fluid leakage amount and ensure the safe operation of the brake system of the vehicle.

[0014] According to some embodiments of the present application, the detection method further comprises:

[0015] When the brake pedal is stepped on, the actual hydraulic volume and the third actual pressure of the servo cylinder are obtained;

[0016] According to the third actual pressure and a theoretical relationship curve, a theoretical hydraulic volume is obtained, the theoretical relationship curve is constructed from preset data of the vehicle and is used to represent the relationship between the pressure and the hydraulic volume of the servo cylinder;

[0017] According to the actual hydraulic volume and the theoretical hydraulic volume, a second brake fluid leakage amount is obtained;

[0018] According to the first brake fluid leakage amount and the second brake fluid leakage amount, a third brake fluid leakage amount is obtained.

[0019] According to some embodiments of the present application, the third brake fluid leakage amount is obtained according to the first brake fluid leakage amount and the second brake fluid leakage amount, which comprises:

[0020] The third brake fluid leakage amount is obtained by the following formula: Q=K1×q1+K2×q2;

[0021] Wherein, Q is the third brake fluid leakage amount, q1 is the first brake fluid leakage amount, K1 is the first weight, q2 is the second brake fluid leakage amount, and K2 is the second weight.

[0022] According to some embodiments of the present application, the third brake fluid leakage amount is obtained according to the first brake fluid leakage amount and the second brake fluid leakage amount, further comprising:

[0023] Obtaining the road condition on which the vehicle is currently running and the lateral acceleration of the vehicle, and changing the values of the first weight and the second weight according to the road condition and the lateral acceleration.

[0024] According to some embodiments of the present application, the second brake fluid leakage amount is obtained according to the actual hydraulic volume and the theoretical hydraulic volume, comprising:

[0025] The second brake fluid leakage amount is obtained by the following formula: q2=d(Va-Vb) / dt;

[0026] Wherein, q2 is the second brake fluid leakage amount, Va is the actual hydraulic volume, Vb is the theoretical hydraulic volume, and d(Va-Vb) / dt is the derivative of the difference between the actual hydraulic volume and the theoretical hydraulic volume.

[0027] According to some embodiments of the present application, the detection method further comprises:

[0028] When the third brake fluid leakage amount is greater than or equal to a leakage amount threshold value, the instrument or central control screen of the vehicle is controlled to issue a reminder to the driver.

[0029] According to some embodiments of the present application, the detection method further comprises:

[0030] Obtaining the stroke gradient of the brake pedal, the actual pressure of the servo cylinder, and the pressure gradient of the servo cylinder;

[0031] When the stroke gradient is greater than 0, the pressure gradient is greater than 0, and the actual pressure is greater than a pressure threshold value, a duration is obtained;

[0032] When the duration is greater than a time threshold value, it is determined that the brake pedal is depressed;

[0033] The detection method further comprises:

[0034] Obtaining the stroke gradient of the brake pedal, the actual pressure of the servo cylinder, and the pressure gradient of the servo cylinder;

[0035] When the stroke gradient is less than or equal to 0, or the pressure gradient is less than or equal to 0, or the actual pressure is less than or equal to a pressure threshold, it is determined that the brake pedal is released.

[0036] According to some embodiments of the present application, the stroke gradient of the brake pedal, the actual pressure of the servo cylinder and the pressure gradient of the servo cylinder are obtained by:

[0037] The actual stroke of the brake pedal is obtained, the actual stroke is discretely derived to obtain the stroke gradient, and the actual pressure is discretely derived to obtain the pressure gradient.

[0038] According to some embodiments of the present application, the first brake fluid leakage quantity is obtained according to the first hydraulic volume, the second hydraulic volume, the first time, the second time and the system hysteresis required fluid quantity, comprising:

[0039] The first brake fluid leakage quantity is obtained by the following formula: q1=(V2-V1-V0) / (T2-T1);

[0040] Wherein, q1 is the first brake fluid leakage quantity, V1 is the first hydraulic volume, T1 is the first time, V2 is the second hydraulic volume, T2 is the second time, V0 is the system hysteresis required fluid quantity.

[0041] According to some embodiments of the present application, the integrated brake control system has a brake, and the system hysteresis required fluid quantity is obtained from preset data of the vehicle, comprising:

[0042] The brake is subjected to pressure-volume characteristic bench test, the brake is controlled to be pressurized, the pressurized pressure-volume characteristic curve of the brake is obtained, and the brake is controlled to be depressurized, the depressurized pressure-volume characteristic curve of the brake is obtained;

[0043] The pressurized hydraulic volume is obtained according to the pressurized pressure-volume characteristic curve and the preset pressure, and the depressurized hydraulic volume is obtained according to the depressurized pressure-volume characteristic curve and the preset pressure;

[0044] The hysteresis required fluid quantity of the brake is obtained according to the pressurized hydraulic volume and the depressurized hydraulic volume;

[0045] The system hysteresis required fluid quantity is obtained according to the hysteresis required fluid quantity of a plurality of brakes.

[0046] According to the vehicle controller of the second aspect of the present application, comprising:

[0047] At least one processor;

[0048] and a memory storing instructions that, when executed by the at least one processor, perform the brake fluid leakage detection method as described above.

[0049] According to the vehicle controller of the embodiment of the present application, at least the following beneficial effects are achieved: the vehicle controller performs the brake fluid leakage detection method, the volume of the leaked brake fluid in the integrated brake control system can be calculated according to the first hydraulic volume, the second hydraulic volume and the system hysteresis required fluid volume, then the time of the leaked brake fluid can be calculated according to the first time and the second time, and then the first brake fluid leakage amount is obtained, so that the brake fluid leakage amount can be accurately calculated, and the safe operation of the brake system of the vehicle is ensured.

[0050] The vehicle according to the third aspect of the embodiment of the present application comprises the vehicle controller according to the second aspect of the embodiment of the present application.

[0051] The vehicle adopts the vehicle controller to perform the brake fluid leakage detection method, the volume of the leaked brake fluid in the integrated brake control system can be calculated according to the first hydraulic volume, the second hydraulic volume and the system hysteresis required fluid volume, then the time of the leaked brake fluid can be calculated according to the first time and the second time, and then the first brake fluid leakage amount is obtained, so that the brake fluid leakage amount can be accurately calculated, and the safe operation of the brake system of the vehicle is ensured.

[0052] Since the vehicle adopts all the technical solutions of the vehicle controller according to the above-mentioned embodiments, at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments are achieved, which will not be described herein again.

[0053] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent to those skilled in the art from the description, or can be learned by practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0054] Fig. 1 is a flowchart of the brake fluid leakage detection method according to an embodiment of the present application;

[0055] Fig. 2 is a flowchart of obtaining the third brake fluid leakage amount according to an embodiment of the present application;

[0056] Fig. 3 is a flowchart of judging that the brake pedal is stepped on according to an embodiment of the present application;

[0057] Fig. 4 is a flowchart of judging that the brake pedal is released according to an embodiment of the present application;

[0058] Fig. 5 is a flowchart of obtaining the system hysteresis required fluid volume according to an embodiment of the present application. DETAILED DESCRIPTION

[0059] Embodiments of the present application will be described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numbers represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application.

[0060] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms front, back, up, down, axial, circumferential, etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as a limitation of the present application.

[0061] In the description of the present application, the meaning of multiple is more than two, greater than, less than, more than, etc. are not included in the number, above, below, within, etc. are included in the number. If it is described as first, second, it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the sequence of indicated technical features.

[0062] In the description of the present application, it should be noted that the words such as setting, mounting, connecting, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0063] The technical solutions of the present application will be described below in conjunction with the drawings. Obviously, the following described embodiments are part of the embodiments of the present application, not all embodiments.

[0064] The integrated brake control system is a brake-by-wire hydraulic brake system that provides assistance to the vehicle. The pressure and displacement of the servo cylinder in the integrated brake control system can be measured and obtained through the self-contained pressure sensor and motor angle sensor, respectively, and then the system hydraulic volume is calculated through the displacement of the servo cylinder.

[0065] Brake fluid is an important component of the automobile brake system, which is responsible for transmitting braking force and ensuring the safe and stable deceleration and parking of the vehicle. If the brake fluid leaks, the performance of the brake system will be severely affected, which may lead to increased braking distance, brake failure, even vehicle out of control, and seriously threaten the life safety of the driver and passengers.

[0066] Through the brake fluid leakage detection method, the problems existing in the brake system can be found in time to avoid potential safety hazards. Once the leakage is detected, the driver can immediately take appropriate measures, such as stopping the vehicle for inspection, contacting the repair site, etc., to ensure that the vehicle is repaired in time to prevent the fault from expanding or causing more serious consequences.

[0067] Brake fluid leakage not only affects the braking effect, but also can cause damage to other components in the braking system. For example, leakage can cause the brake pump to overheat, the brake disc and brake pad to wear out, etc. By detecting and repairing the leakage problem in a timely manner, the service life of the braking system and related components can be effectively extended, and maintenance costs can be reduced.

[0068] The normal operation of the braking system is crucial to the driving experience of the driver. Brake fluid leakage can cause problems such as abnormal brake pedal feel, sluggish brake response, etc., affecting the driving confidence and comfort of the driver. By detecting and handling the leakage problem in a timely manner, the normal operation of the braking system can be ensured, and the driving experience can be improved.

[0069] In the prior art, the integrated brake control system pre-stores preset pressures corresponding to different depths of the brake pedal being depressed. When the driver depresses the brake pedal to control the vehicle to brake, the corresponding preset pressure is retrieved according to the depth of the brake pedal being depressed, the measured pressure of the servo cylinder is measured, and the measured pressure and the preset pressure are compared. If the measured pressure is lower than the preset pressure, it proves that the brake fluid is leaking.

[0070] The prior art detects brake fluid leakage according to the difference between the calibrated preset pressure and the measured pressure, and cannot accurately obtain the leakage amount. Since the pressure-volume characteristics of the vehicle brake vary on different samples, and the brake clearance increases during the vehicle driving process, the pressure-volume characteristics of the brake also do not conform to the calibration, in addition, there is a possibility of air intake during the use of the braking system, therefore, the leakage detection method is susceptible to the pressure-volume changes and air content of the braking system, and there is a risk of misjudgment of the leakage problem.

[0071] The brake fluid leakage detection method of the embodiment of the present application is described with reference to FIGS. 1 to 5, and the brake fluid leakage detection method is applied to a vehicle having an integrated brake control system, and the integrated brake control system has a servo cylinder and a brake pedal.

[0072] Referring to FIG. 1, the brake fluid leakage detection method of the embodiment of the present application includes the following steps.

[0073] Step S100, when the brake pedal is depressed, the first actual pressure of the servo cylinder is obtained.

[0074] It can be understood that after the driver depresses the brake pedal, the integrated brake control system will brake the vehicle, causing the pressure of the servo cylinder to rise, and the first actual pressure is measured by the pressure sensor of the servo cylinder, and the first actual pressure will change with the depth of the brake pedal being depressed by the driver.

[0075] Step S200, when the first actual pressure rises to the preset pressure, the first hydraulic volume of the servo cylinder and the first time are obtained.

[0076] The preset pressure is set in the integrated brake control system of the vehicle. When the first actual pressure gradually rises to the preset pressure, the current time is recorded as the first time. The displacement of the servo cylinder is measured by the motor angle sensor of the servo cylinder, and the first hydraulic volume of the servo cylinder is calculated.

[0077] Step S300, when the brake pedal is released, the second actual pressure of the servo cylinder is obtained.

[0078] It can be understood that after the driver releases the brake pedal, the integrated brake control system releases the brake of the vehicle, so that the pressure of the servo cylinder decreases, and the second actual pressure is measured by the pressure sensor of the servo cylinder, and the second actual pressure gradually decreases with the increase of the time when the brake pedal is released.

[0079] Step S400, when the second actual pressure decreases to the preset pressure, the second hydraulic volume of the servo cylinder and the second time are obtained.

[0080] The preset pressure is set in the integrated brake control system of the vehicle. When the second actual pressure gradually decreases to the preset pressure, the current time is recorded as the second time. The displacement of the servo cylinder is measured by the motor angle sensor of the servo cylinder, and the second hydraulic volume of the servo cylinder is calculated.

[0081] Step S500, according to the first hydraulic volume, the second hydraulic volume, the first time, the second time and the system hysteresis required liquid volume, the first brake fluid leakage is obtained, the system hysteresis required liquid volume is obtained from the preset data of the vehicle, and the system hysteresis required liquid volume is used to represent the volume of the brake fluid output by the servo cylinder when the pressure of the servo cylinder reaches the preset pressure.

[0082] It can be understood that in the pressurization working condition and the pressure reduction working condition, the hydraulic volume in the servo cylinder changes, and the preset pressure is taken as the sampling condition. When the first actual pressure of the servo cylinder reaches the preset pressure in the pressurization working condition, the first hydraulic volume is obtained. When the second actual pressure of the servo cylinder reaches the preset pressure in the pressure reduction working condition, the second hydraulic volume is obtained. During the transmission of the brake fluid in the pressurization working condition and the pressure reduction working condition, part of the brake fluid will stay in the pipeline or the brake and other components. The pressure of the servo cylinder is measured to reach the preset pressure in the pressurization working condition and the pressure reduction working condition through the vehicle development stage of the whole vehicle test. The volume of the brake fluid output by the servo cylinder in the pressure reduction working condition is subtracted from the volume of the brake fluid output by the servo cylinder in the pressurization working condition, and the difference is the system hysteresis required liquid volume.

[0083] In some embodiments, the step S500 further comprises the following steps.

[0084] The first brake fluid leakage quantity is obtained by the following formula: q1=(V2-V1-V0) / (T2-T1).

[0085] Wherein, q1 is the first brake fluid leakage quantity, V1 is the first hydraulic volume, T1 is the first time, V2 is the second hydraulic volume, T2 is the second time, and V0 is the system hysteresis fluid requirement quantity.

[0086] The first hydraulic volume V1, the second hydraulic volume V2 and the system hysteresis fluid requirement quantity V0 obtained by the preset pressure as the sampling condition are used as conditions to determine whether the integrated brake control system leaks.

[0087] Normally, the difference between the first hydraulic volume V1 and the second hydraulic volume V2 should be equal to the system hysteresis fluid requirement quantity V0 when the integrated brake control system is running normally.

[0088] Therefore, the volume of brake fluid leakage is calculated by the first hydraulic volume V1, the second hydraulic volume V2 and the system hysteresis fluid requirement quantity V0, then the difference between the first time T1 and the second time T2 is calculated as the brake fluid leakage time, and the volume of brake fluid leakage is divided by the brake fluid leakage time to obtain the first brake fluid leakage quantity q1, which represents the leakage quantity of the integrated brake control system of the vehicle per unit time.

[0089] Referring to FIG. 1, in some embodiments, the brake fluid leakage detection method further comprises the following steps.

[0090] Step S600, when the brake pedal is depressed, the actual hydraulic volume and the third actual pressure of the servo cylinder are obtained.

[0091] It can be understood that when the driver depresses the brake pedal, both the step S100 and the step S600 are triggered, i.e., the step S100 and the step S600 can be operated synchronously.

[0092] After the driver depresses the brake pedal, the displacement of the servo cylinder is measured by the motor angle sensor of the servo cylinder, and then the actual hydraulic volume of the servo cylinder is calculated, and the actual hydraulic volume changes with the distance of the driver depressing the brake pedal.

[0093] It can be understood that after the driver steps on the brake pedal, the integrated brake control system brakes the vehicle, the pressure of the servo cylinder rises, and the third actual pressure is measured by the pressure sensor of the servo cylinder, and the third actual pressure changes with the depth of the driver stepping on the brake pedal.

[0094] In step S700, a theoretical hydraulic volume is obtained according to the third actual pressure and a theoretical relationship curve, the theoretical relationship curve is constructed by preset data of the vehicle, and is used to represent the relationship between the pressure of the servo cylinder and the hydraulic volume.

[0095] Since steps S100 and S600 can be synchronously operated, the third actual pressure of the servo cylinder can be measured by the pressure sensor of the servo cylinder.

[0096] The theoretical relationship curve is obtained by vehicle test in the vehicle development stage, in the test process, by changing the hydraulic volume of the servo cylinder, the pressure of the servo cylinder under different hydraulic volumes is measured by the pressure sensor, and then the relationship curve between the pressure and the hydraulic volume is formed.

[0097] Therefore, the corresponding hydraulic volume can be found in the theoretical relationship curve by the pressure. In the embodiment, the corresponding theoretical hydraulic volume is found in the theoretical relationship curve according to the third actual pressure of the servo cylinder.

[0098] In step S800, a second brake fluid leakage amount is obtained according to the actual hydraulic volume and the theoretical hydraulic volume.

[0099] Since the theoretical hydraulic volume is a theoretical data obtained based on the vehicle test, in the process of vehicle driving, the displacement of the servo cylinder is measured by the motor angle sensor of the servo cylinder and calculated to obtain the corresponding actual hydraulic volume.

[0100] In some embodiments, step S800, obtaining the second brake fluid leakage amount according to the actual hydraulic volume and the theoretical hydraulic volume, further includes the following steps.

[0101] In step S801, the second brake fluid leakage amount is obtained by the following formula: q2=d(Va-Vb) / dt.

[0102] Wherein, q2 is the second brake fluid leakage amount, Va is the actual hydraulic volume, Vb is the theoretical hydraulic volume, and d(Va-Vb) / dt is the derivative of the difference between the actual hydraulic volume and the theoretical hydraulic volume.

[0103] Normally, when the integrated brake control system is normally operated, the actual hydraulic volume Va should be equal to the theoretical hydraulic volume Vb.

[0104] When the integrated brake control system leaks brake fluid, the actual hydraulic volume Va is different from the theoretical hydraulic volume Vb. The volume of the leaked brake fluid can be obtained by calculating the difference between the actual hydraulic volume Va and the theoretical hydraulic volume Vb.

[0105] Then, the actual hydraulic volume Va and the theoretical hydraulic volume Vb at multiple different time points are obtained, and the second brake fluid leakage q2 is obtained by deriving the discrete data.

[0106] In step S900, the third brake fluid leakage is obtained according to the first brake fluid leakage and the second brake fluid leakage.

[0107] The first brake fluid leakage and the second brake fluid leakage obtained by the two methods can be calculated to obtain the third brake fluid leakage by defining different weights for the first brake fluid leakage and the second brake fluid leakage, so as to determine the brake fluid leakage of the vehicle through the third brake fluid leakage.

[0108] Referring to FIG. 1, in some embodiments, the brake fluid leakage detection method further includes the following steps.

[0109] In step S1000, when the third brake fluid leakage is greater than or equal to the leakage threshold, the instrument or the central control screen of the vehicle is controlled to remind the driver.

[0110] When the third brake fluid leakage exceeds the leakage threshold, it proves that the brake fluid leakage of the vehicle exceeds the safe driving limit, so the driver needs to be warned and prompted, and the single-pipe brake pressure building is switched to in time to ensure the safety of the brake system.

[0111] When the driver is warned and prompted, the instrument or the central control screen of the vehicle can be controlled to remind the driver to obtain information that the brake fluid leakage exceeds the safe range from the instrument or the central control screen.

[0112] The single-pipe brake pressure building is to use a master cylinder to control all brakes through a set of connected pipelines to build brake pressure.

[0113] Referring to FIG. 2, in step S900, the third brake fluid leakage is obtained according to the first brake fluid leakage and the second brake fluid leakage, including the following steps.

[0114] In step S910, the third brake fluid leakage is obtained by the following formula: Q=K1×q1+K2×q2.

[0115] Wherein, Q is the third brake fluid leakage, q1 is the first brake fluid leakage, K1 is the first weight, q2 is the second brake fluid leakage, and K2 is the second weight.

[0116] It can be understood that the first brake fluid leakage amount q1 and the second brake fluid leakage amount q2 can be individually used as the result of the vehicle brake fluid leakage amount, and the two calculation results of the first brake fluid leakage amount q1 and the second brake fluid leakage amount q2 are respectively obtained by using different measurement data in the vehicle, so the calculation results are inevitably affected by the measurement accuracy.

[0117] Therefore, in order to reduce the influence of measurement accuracy on the brake fluid leakage amount, a first weight K1 is defined for the first brake fluid leakage amount q1, a second weight K2 is defined for the second brake fluid leakage amount q2, and the first brake fluid leakage amount q1 and the second brake fluid leakage amount q2 calculated in two ways are weighted and calculated to obtain a third brake fluid leakage amount Q.

[0118] The actual values of the first weight K1 and the second weight K2 can be obtained by testing and calibrating the detection method during the development stage of the vehicle.

[0119] In step S920, the road condition of the vehicle currently driving and the lateral acceleration of the vehicle are obtained, and the proportion of the first weight K1 and the second weight K2 is changed according to the road condition and the lateral acceleration.

[0120] It can be understood that the road condition of the vehicle driving will affect the operation of the four brakes of the vehicle. For example, when the vehicle is driving on a bumpy road, the wheels are shaken by the bumpy road, causing the piston of the brake to be impacted and returned, that is, the required pressure of the brake increases, and then the hydraulic volume of the servo cylinder changes, which changes the actual measured hydraulic volume, and then affects the second brake fluid leakage amount q2.

[0121] Therefore, if the road is bumpy, the proportion of the second weight K2 will be reduced.

[0122] The road image in front of the vehicle can be obtained through the sensor of the vehicle, and the road condition can be analyzed through the road image.

[0123] The driving condition of the vehicle can also be obtained according to the sensor inside the vehicle, and whether the vehicle is driving on a bumpy road can be determined according to the driving condition.

[0124] The lateral acceleration of the vehicle refers to the acceleration of the vehicle perpendicular to the driving direction of the vehicle during driving due to a large turning angle. The lateral acceleration of the vehicle also affects the operation of the four brakes of the vehicle. Due to a large steering angle of the wheels, the piston of the brake is impacted and returned, that is, the required pressure of the brake increases, and then the hydraulic volume of the servo cylinder changes, which changes the actual measured hydraulic volume, and then affects the second brake fluid leakage amount q2.

[0125] To this end, if the lateral acceleration of the vehicle exceeds an acceleration threshold, the proportion of the second weight K2 will be reduced. Of course, a plurality of different acceleration thresholds can also be set according to the lateral acceleration, and a corresponding second weight K2 is set for each acceleration threshold.

[0126] The steering angle of the wheel can be obtained by a sensor of the vehicle, and the lateral acceleration is calculated according to the self-weight of the vehicle and the current driving speed.

[0127] Of course, a sensor for measuring the lateral acceleration can be arranged on the vehicle to directly obtain the lateral acceleration of the vehicle.

[0128] Referring to FIG. 3, the detection method further comprises the following steps.

[0129] In step S110, the stroke gradient of the brake pedal, the actual pressure of the servo cylinder and the pressure gradient of the servo cylinder are obtained.

[0130] The stroke and acceleration when the driver steps on the brake pedal are measured by a pedal simulator or a stroke sensor, and the stroke gradient of the brake pedal is calculated by the stroke and the acceleration.

[0131] Alternatively, the actual stroke of the brake pedal is obtained multiple times, and the stroke gradient is obtained by discrete derivation on the multiple actual strokes.

[0132] After the driver steps on the brake pedal, the integrated brake control system brakes the vehicle, so that the pressure of the servo cylinder rises, and the actual pressure is measured by the pressure sensor of the servo cylinder, and the actual pressure changes with the depth of the brake pedal stepped on by the driver.

[0133] The actual pressure of the servo cylinder is obtained multiple times, and the pressure gradient is obtained by discrete derivation on the multiple actual pressures.

[0134] In step S120, when the stroke gradient is greater than 0, the pressure gradient is greater than 0, and the actual pressure is greater than the pressure threshold, the duration is obtained.

[0135] When the stroke gradient of the brake pedal is greater than 0, it proves that the driver is stepping down the brake pedal, rather than releasing the brake pedal.

[0136] When the pressure gradient of the servo cylinder is greater than 0, it proves that the pressure of the servo cylinder is rising, and the servo cylinder is in a pressure increasing condition.

[0137] Since the actual pressure of the servo cylinder may be lower than the preset pressure when the driver steps on the brake pedal, the pressure threshold needs to be set, and the pressure threshold is greater than or equal to the preset pressure, so as to ensure that the servo cylinder can reach the preset pressure in the pressure increasing condition.

[0138] When the above three conditions are met, it is proved that the driver steps on the brake pedal, and then the duration of the brake pedal being stepped on is obtained.

[0139] Step S130, when the duration is greater than the time threshold value, it is determined that the brake pedal is stepped on.

[0140] The time threshold value is set, and when the duration of the driver stepping on the brake pedal exceeds the time threshold value, it can be determined that the brake pedal is stepped on.

[0141] Referring to FIG. 4, the detection method further comprises the following steps.

[0142] Step S310, the stroke gradient of the brake pedal, the actual pressure of the servo cylinder and the pressure gradient of the servo cylinder are obtained.

[0143] The stroke and acceleration when the brake pedal is released are measured by the pedal simulator or the stroke sensor, and the stroke gradient of the brake pedal is calculated by the stroke and the acceleration.

[0144] Alternatively, the actual stroke of the brake pedal is obtained multiple times, and the stroke gradient is obtained by discrete derivation on multiple actual strokes.

[0145] After the driver releases the brake pedal, the integrated brake control system releases the brake of the vehicle, the pressure of the servo cylinder decreases, and the actual pressure is measured by the pressure sensor of the servo cylinder, and the actual pressure gradually decreases with the increase of the time when the brake pedal is released.

[0146] The actual pressure of the servo cylinder is obtained multiple times, and the pressure gradient is obtained by discrete derivation on multiple actual pressures.

[0147] Step S320, when the stroke gradient is less than or equal to 0, or the pressure gradient is less than or equal to 0, or the actual pressure is less than or equal to the pressure threshold value, it is determined that the brake pedal is released.

[0148] After it is determined that the brake pedal is stepped on and the corresponding data is obtained, it is necessary to judge whether the brake pedal is released.

[0149] When the stroke gradient of the brake pedal is less than or equal to 0, it is proved that the driver releases the brake pedal.

[0150] When the pressure gradient of the servo cylinder is greater than 0, it is proved that the pressure of the servo cylinder is decreasing, the servo cylinder is in the pressure reducing condition, and the driver releases the brake pedal.

[0151] When the actual pressure of the servo cylinder does not reach the pressure threshold value, the driver is a light brake pedal, even if the stroke gradient of the brake pedal and the pressure gradient of the servo cylinder are both greater than 0, but the actual pressure of the servo cylinder has decreased to below the preset pressure, it is sufficient to obtain the relevant data in the pressure reducing condition, and it can also be determined that the driver releases the brake pedal.

[0152] Referring to FIG. 5, in some embodiments, the integrated brake control system has a brake, step S500, and the system hysteresis fluid requirement is obtained from preset data of the vehicle, including the following steps.

[0153] Step S510, pressure-volume characteristic bench test is performed on the brake, the brake is controlled to be pressurized to obtain a pressurization pressure-volume characteristic curve of the brake, and the brake is controlled to be depressurized to obtain a depressurization pressure-volume characteristic curve of the brake.

[0154] The pressure-volume characteristic bench test is performed on the front and rear brakes of the vehicle in the vehicle development stage. Different from the previous pressure-volume characteristic, the test is to obtain the hysteresis volume characteristic of the front and rear brakes due to the friction plate compression rate and the like. The previous brake pressure-volume characteristic bench test only needs to focus on the volume value when the pressure increases, but the test needs to be pressurized and depressurized in two working conditions to obtain the pressurization pressure-volume characteristic in the pressurization working condition and the depressurization pressure-volume characteristic curve in the depressurization working condition.

[0155] Step S520, the pressurization hydraulic volume is obtained according to the pressurization pressure-volume characteristic curve and the preset pressure, and the depressurization hydraulic volume is obtained according to the depressurization pressure-volume characteristic curve and the preset pressure.

[0156] The first hydraulic volume is obtained at the preset pressure in the pressurization working condition, and the second hydraulic volume is obtained at the preset pressure in the depressurization working condition. The corresponding pressurization hydraulic volume is found in the pressurization pressure-volume characteristic curve under the condition of the preset pressure in the pressurization working condition, and the pressurization hydraulic volume represents the brake fluid volume required by the single brake of the vehicle when the pressure rises and reaches the preset pressure. The corresponding depressurization hydraulic volume is found in the depressurization pressure-volume characteristic curve under the condition of the preset pressure in the depressurization working condition, and the depressurization hydraulic volume represents the brake fluid volume required by the single brake of the vehicle when the pressure drops and reaches the preset pressure.

[0157] Step S530, the hysteresis fluid requirement of the brake is obtained according to the pressurization hydraulic volume and the depressurization hydraulic volume.

[0158] The hysteresis fluid requirement of the single brake is obtained by subtracting the pressurization hydraulic volume from the depressurization hydraulic volume.

[0159] Step S540, the system hysteresis fluid requirement is obtained according to the hysteresis fluid requirements of the multiple brakes.

[0160] The system hysteresis fluid requirement is obtained by summing up the hysteresis fluid requirements of the four brakes of the vehicle.

[0161] For example, the boost pressure volume characteristic curve of the boost working condition is interpolated with the target pressure P0 to obtain the boost hydraulic volume Vinc corresponding to the boost working condition; and the deboost pressure volume characteristic curve is interpolated with the target pressure P0 to obtain the deboost hydraulic volume Vdec corresponding to the deboost working condition.

[0162] The deboost hydraulic volume Vdec is subtracted from the boost hydraulic volume Vinc to obtain Vhyst, and the hysteresis required hydraulic volumes of the four brakes are summed to obtain the system hysteresis required hydraulic volume V0, i.e., Vhyst1 = Vdec1-Vinc1; Vhyst2 = Vdec2-Vinc2; Vhyst3 = Vdec3-Vinc3; Vhyst4 = Vdec4-Vinc4; V0 = Vhyst1+Vhyst2+Vhyst3+Vhyst4.

[0163] The brake fluid leakage detection method of the embodiment can measure and obtain the pressure and displacement of the servo cylinder in the integrated brake control system through the self-provided pressure sensor and motor angle sensor, and calculate the system hydraulic volume through the displacement of the servo cylinder.

[0164] The system leakage amount is detected in the following two ways.

[0165] The first way is that the driver exists the process of stepping on the brake and releasing the brake every time the driver brakes, at which time the pressure volume and corresponding time of stepping on the brake and releasing the brake are recorded, the volume difference of the driver braking is obtained by subtracting the brake fluid hysteresis volume of the brake from the hydraulic volume difference of the brake fluid at a specific target pressure, and the first brake fluid leakage amount in the circuit is calculated by dividing the time difference of the brake fluid at the target pressure.

[0166] The second way is that the driver continuously monitors the pressure volume of the brake system during braking, and the servo cylinder volume corresponding to different brake pressures is obtained in real time, and the displacement difference is obtained by subtracting the calibrated pressure volume from the servo cylinder volume, and the second brake fluid leakage amount is obtained by deriving the displacement difference.

[0167] Different weights are defined for the leakage amounts obtained by the two ways respectively, and the third brake fluid leakage amount is calculated, when the third brake fluid leakage amount reaches the leakage amount threshold value, the driver needs to be warned and prompted, and the single-pipeline brake pressure is built to ensure the safety of the brake system.

[0168] The brake fluid leakage detection method is of great significance for ensuring driving safety, preventing brake system damage, and improving driving experience.

[0169] Specifically, referring to FIG. 1, the brake fluid leakage detection method of the embodiment includes the following steps.

[0170] After the driver steps on the brake pedal, the integrated brake control system brakes the vehicle, the pressure of the servo cylinder rises, and the first actual pressure is measured by the pressure sensor of the servo cylinder, and the first actual pressure changes with the depth of the driver stepping on the brake pedal.

[0171] In the integrated brake control system of the vehicle, a preset pressure is set, and when the first actual pressure gradually rises to the preset pressure, the current time is recorded as the first time, the displacement of the servo cylinder is measured by the motor angle sensor of the servo cylinder, and the first hydraulic volume of the servo cylinder is calculated.

[0172] After the driver releases the brake pedal, the integrated brake control system releases the brake of the vehicle, the pressure of the servo cylinder decreases, and the second actual pressure is measured by the pressure sensor of the servo cylinder, and the second actual pressure gradually decreases with the increase of the time when the brake pedal is released.

[0173] In the integrated brake control system of the vehicle, a preset pressure is set, and when the second actual pressure gradually decreases to the preset pressure, the current time is recorded as the second time, the displacement of the servo cylinder is measured by the motor angle sensor of the servo cylinder, and the second hydraulic volume of the servo cylinder is calculated.

[0174] In the pressurization and decompression conditions, the hydraulic volume inside the servo cylinder changes, and the preset pressure is taken as the sampling condition. When the first actual pressure reaches the preset pressure in the pressurization condition of the servo cylinder, the first hydraulic volume is obtained; when the second actual pressure reaches the preset pressure in the decompression condition of the servo cylinder, the second hydraulic volume is obtained; and during the transmission of brake fluid in the pressurization and decompression conditions of the servo cylinder, part of the brake fluid will stay in the pipeline or brake and other components. Through the vehicle test in the development stage of the vehicle, it is measured that the pressure of the servo cylinder reaches the preset pressure in the pressurization and decompression conditions, and the volume of brake fluid output by the servo cylinder in the decompression condition is subtracted from the volume of brake fluid output by the servo cylinder in the pressurization condition, and the difference is the system hysteresis required liquid volume.

[0175] The first brake fluid leakage amount q1 is obtained by the following formula: q1=(V2-V1-V0) / (T2-T1), the first hydraulic volume is V1, the second hydraulic volume is V2, the system hysteresis required liquid volume is V0, the first time is T1, and the second time is T2.

[0176] Normally, when the integrated brake control system is normally running, the difference between the first hydraulic volume V1 and the second hydraulic volume V2 should be equal to the system hysteresis required liquid volume V0.

[0177] Therefore, the volume of the brake fluid leakage is calculated by the first hydraulic volume V1, the second hydraulic volume V2 and the system hysteresis required volume V0, then the difference between the first time T1 and the second time T2 is calculated as the brake fluid leakage time, and the first brake fluid leakage quantity q1 is obtained by dividing the volume of the brake fluid leakage by the brake fluid leakage time, which represents the leakage quantity of the integrated brake control system of the vehicle per unit time.

[0178] After the driver steps on the brake pedal, the displacement of the servo cylinder is measured by the motor angle sensor of the servo cylinder, and the actual hydraulic volume of the servo cylinder is calculated, and the actual hydraulic volume changes with the distance of the driver stepping on the brake pedal.

[0179] After the driver steps on the brake pedal, the integrated brake control system brakes the vehicle, the pressure of the servo cylinder rises, and the third actual pressure is measured by the pressure sensor of the servo cylinder, and the third actual pressure changes with the depth of the driver stepping on the brake pedal.

[0180] The theoretical relationship curve is obtained by vehicle development stage through vehicle test, in the test process, by changing the hydraulic volume of the servo cylinder, the pressure of the servo cylinder under different hydraulic volumes is measured by the pressure sensor, and then the relationship curve between the pressure and the hydraulic volume is formed.

[0181] Therefore, the corresponding hydraulic volume can be found in the theoretical relationship curve by searching the pressure. In this embodiment, the corresponding theoretical hydraulic volume is found in the theoretical relationship curve according to the third actual pressure of the servo cylinder.

[0182] Since the theoretical hydraulic volume is a theoretical data obtained based on the vehicle test, in the process of vehicle driving, the displacement of the servo cylinder is measured by the motor angle sensor of the servo cylinder and calculated to obtain the corresponding actual hydraulic volume.

[0183] The second brake fluid leakage quantity q2 is obtained by the following formula: q2=d(Va-Vb) / dt. The second brake fluid leakage quantity is q2, the actual hydraulic volume is Va, the theoretical hydraulic volume is Vb, and d(Va-Vb) / dt is the derivative of the difference between the actual hydraulic volume and the theoretical hydraulic volume.

[0184] Normally, when the integrated brake control system is normally running, the actual hydraulic volume Va should be equal to the theoretical hydraulic volume Vb.

[0185] When the integrated brake control system has brake fluid leakage, there is a difference between the actual hydraulic volume Va and the theoretical hydraulic volume Vb, and the volume of the brake fluid leakage can be obtained by calculating the difference between the actual hydraulic volume Va and the theoretical hydraulic volume Vb.

[0186] Then, the actual hydraulic volume Va and the theoretical hydraulic volume Vb at multiple different time points are obtained, and the second brake fluid leakage q2 is obtained by derivation of discrete data.

[0187] The first brake fluid leakage and the second brake fluid leakage obtained by the two methods can be used to calculate the third brake fluid leakage by defining different weights for the first brake fluid leakage and the second brake fluid leakage, so as to determine the brake fluid leakage of the vehicle through the third brake fluid leakage.

[0188] The third brake fluid leakage Q is obtained by the following formula: Q=K1×q1+K2×q2.

[0189] The third brake fluid leakage is Q, the first weight is K1, and the second weight is K2.

[0190] It can be understood that the first brake fluid leakage q1 and the second brake fluid leakage q2 can each be used as a result of the brake fluid leakage of the vehicle, and the two calculation results of the first brake fluid leakage q1 and the second brake fluid leakage q2 each use different measurement data in the vehicle, so the calculation results are inevitably affected by the measurement accuracy.

[0191] Therefore, in order to reduce the influence of the measurement accuracy on the brake fluid leakage, the first weight K1 is defined for the first brake fluid leakage q1, the second weight K2 is defined for the second brake fluid leakage q2, and the first brake fluid leakage q1 and the second brake fluid leakage q2 calculated by the two methods are weighted and calculated to obtain the third brake fluid leakage Q.

[0192] The actual values of the first weight K1 and the second weight K2 can be calibrated by using the detection method to test the vehicle in the development stage.

[0193] When the third brake fluid leakage Q exceeds the leakage threshold value, it is proved that the brake fluid leakage of the vehicle exceeds the limit of safe driving, so the driver needs to be warned and prompted, and the single-pipe brake pressure building needs to be switched to ensure the safety of the brake system.

[0194] In addition, the embodiment of the present application also provides a vehicle controller, which comprises at least one processor and a memory storing instructions, when the instructions are executed by the at least one processor, the brake fluid leakage detection method of the above-mentioned embodiment is executed.

[0195] For example, the processor and the memory in the vehicle controller can be connected by a bus. The memory, as a non-transitory computer readable storage medium, can be used to store non-transitory software programs and non-transitory computer executable programs. In addition, the memory can include high-speed random access memory and can also include non-transitory memory, such as at least one disk memory, a flash memory device, or other non-transitory solid-state memory device. In some embodiments, the memory can optionally include a memory remotely arranged relative to the control processor, which can be connected to the controller through a network.

[0196] The non-transitory software programs and instructions required to implement the detection method of the above embodiments are stored in the memory, and when executed by the processor, the detection method in the above embodiments is executed, for example, the method steps S100 to S1000 in Figure 1, the method steps S910 to S920 in Figure 2, the method steps S110 to S130 in Figure 3, the method steps S310 to S320 in Figure 4, the method steps S510 to S540 in Figure 5, etc. described above.

[0197] The above-described device embodiments are only illustrative, and units described as separate components can or can not be physically separated, i.e., can be located in one place or can be distributed to multiple network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the present embodiment.

[0198] The embodiments of the present application also provide a vehicle comprising the vehicle controller of the above embodiments. The vehicle can be a private car, such as a sedan, an SUV, an MPV, or a pickup truck, etc. The vehicle can also be an operating vehicle, such as a van, a bus, a small truck, or a large trailer, etc. The vehicle can be a gasoline car or a new energy car. When the vehicle is a new energy car, it can be a hybrid car or a pure electric car.

[0199] The vehicle adopts the vehicle controller to execute the brake fluid leakage detection method, according to the first hydraulic volume, the second hydraulic volume, and the system hysteresis required fluid volume, the volume of the leaked brake fluid in the integrated brake control system can be calculated, and then the time of the leaked brake fluid is calculated according to the first time and the second time, and then the first brake fluid leakage amount is obtained, which can accurately calculate the brake fluid leakage amount and ensure the safe operation of the brake system of the vehicle.

[0200] In several embodiments provided in the present application, it should be understood that the disclosed apparatus and method can be implemented by other manners. For example, the apparatus embodiments described above are merely illustrative, for example, the division of the above units is merely a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0201] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they can be located in one place, or they can be distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0202] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0203] If the integrated unit is realized in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application or the whole or part of the technical solutions that essentially contribute to the prior art can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method of each embodiment of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various program storage media.

[0204] The embodiments of the present application are described in detail above in combination with the drawings, but the present application is not limited to the above embodiments. Within the knowledge of those skilled in the art, various changes can be made without departing from the spirit of the present application.

Claims

1. A method for detecting brake fluid leakage, characterized in that, The detection method, applicable to vehicles with an integrated braking control system including a servo cylinder and a brake pedal, includes: When the brake pedal is depressed, the first actual pressure of the servo cylinder is obtained; When the first actual pressure rises to the preset pressure, the first hydraulic volume and the first moment of the servo cylinder are obtained; When the brake pedal is released, the second actual pressure of the servo cylinder is obtained; When the second actual pressure decreases to the preset pressure, the second hydraulic volume and the second moment of the servo cylinder are obtained. The first brake fluid leakage amount is obtained based on the first hydraulic volume, the second hydraulic volume, the first time, the second time, and the system hysteresis fluid requirement. The system hysteresis fluid requirement is obtained from the vehicle's preset data. The system hysteresis fluid requirement is used to characterize the volume of brake fluid output by the servo cylinder when the pressure of the servo cylinder reaches the preset pressure.

2. The brake fluid leakage detection method according to claim 1, characterized in that, The detection method further includes: When the brake pedal is depressed, the actual hydraulic volume and third actual pressure of the servo cylinder are obtained; The theoretical hydraulic volume is obtained based on the third actual pressure and theoretical relationship curve. The theoretical relationship curve is constructed from the preset data of the vehicle and is used to characterize the relationship between the pressure and hydraulic volume of the servo cylinder. The second brake fluid leakage amount is obtained based on the actual hydraulic volume and the theoretical hydraulic volume; The third brake fluid leakage amount is obtained based on the first brake fluid leakage amount and the second brake fluid leakage amount.

3. The brake fluid leakage detection method according to claim 2, characterized in that, The step of obtaining the third brake fluid leakage amount based on the first brake fluid leakage amount and the second brake fluid leakage amount includes: The third brake fluid leakage amount is obtained using the following formula: Q = K1 × q1 + K2 × q2; Where Q is the third brake fluid leakage amount, q1 is the first brake fluid leakage amount, K1 is the first weight, q2 is the second brake fluid leakage amount, and K2 is the second weight.

4. The brake fluid leakage detection method according to claim 3, characterized in that, The method of obtaining the third brake fluid leakage amount based on the first brake fluid leakage amount and the second brake fluid leakage amount further includes: The vehicle obtains the current road conditions and the vehicle's lateral acceleration, and adjusts the values ​​of the first weight and the second weight according to the road conditions and the lateral acceleration.

5. The brake fluid leakage detection method according to claim 2, characterized in that, The step of obtaining the second brake fluid leakage amount based on the actual hydraulic volume and the theoretical hydraulic volume includes: The second brake fluid leakage amount is obtained using the following formula: q2 = d(Va - Vb) / dt; Where q2 is the second brake fluid leakage amount, Va is the actual hydraulic volume, Vb is the theoretical hydraulic volume, and d(Va-Vb) / dt is the discrete data derivative of the difference between the actual hydraulic volume and the theoretical hydraulic volume.

6. The brake fluid leakage detection method according to claim 2, characterized in that, The detection method further includes: When the leakage of the third brake fluid is greater than or equal to the leakage threshold, the instrument panel or central control screen of the vehicle will issue a reminder to the driver.

7. The brake fluid leakage detection method according to claim 1, characterized in that, The detection method further includes: Obtain the travel gradient of the brake pedal, the actual pressure of the servo cylinder, and the pressure gradient of the servo cylinder; The duration is obtained when the stroke gradient is greater than 0, the pressure gradient is greater than 0, and the actual pressure is greater than the pressure threshold. When the duration exceeds a time threshold, it is determined that the brake pedal has been depressed. The detection method further includes: Obtain the travel gradient of the brake pedal, the actual pressure of the servo cylinder, and the pressure gradient of the servo cylinder; The brake pedal is determined to be released when the stroke gradient is less than or equal to 0, the pressure gradient is less than or equal to 0, or the actual pressure is less than or equal to the pressure threshold.

8. The brake fluid leakage detection method according to claim 7, characterized in that, The process of obtaining the travel gradient of the brake pedal, the actual pressure of the servo cylinder, and the pressure gradient of the servo cylinder includes: The actual travel of the brake pedal is obtained, the travel gradient is obtained by discrete differentiation of the actual travel, and the pressure gradient is obtained by discrete differentiation of the actual pressure.

9. The brake fluid leakage detection method according to claim 1, characterized in that, The step of obtaining the first brake fluid leakage amount based on the first hydraulic volume, the second hydraulic volume, the first moment, the second moment, and the system hysteresis fluid requirement includes: The first brake fluid leakage amount is obtained using the following formula: q1 = (V2 - V1 - V0) / (T2 - T1); Wherein, q1 is the first brake fluid leakage amount, V1 is the first hydraulic volume, T1 is the first moment, V2 is the second hydraulic volume, T2 is the second moment, and V0 is the system hysteresis fluid requirement.

10. The brake fluid leakage detection method according to claim 1, characterized in that, The integrated braking control system includes a brake, and the required hysteresis fluid volume is obtained from preset data of the vehicle, including: A pressure-volume characteristic bench test was conducted on the brake. The brake was pressurized to obtain the pressurization pressure-volume characteristic curve of the brake, and the brake was depressurized to obtain the depressurization pressure-volume characteristic curve of the brake. The boosted hydraulic volume is obtained based on the boosted pressure-volume characteristic curve and the preset pressure, and the depressurization pressure is determined accordingly. The pressure-volume characteristic curve and the preset pressure are used to obtain the depressurized hydraulic volume; The hysteresis fluid requirement of the brake is obtained based on the pressurized hydraulic volume and the depressurized hydraulic volume. The system hysteresis fluid requirement is obtained based on the hysteresis fluid requirement of the multiple brakes.

11. A vehicle controller, characterized in that, include: At least one processor; And a memory storing instructions that, when executed by at least one processor, perform the brake fluid leakage detection method as described in any one of claims 1 to 10.

12. A vehicle, characterized in that, Includes the vehicle controller as described in claim 11.

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