Brake pedal push rod stroke amount correction method and device, vehicle and storage medium

Abstract

The invention relates to a brake pedal push rod stroke amount correction method, which comprises the following steps: when a vehicle satisfies a brake pedal push rod stroke amount correction condition, calculating the deviation between a push rod stroke actual measurement and a push rod stroke calculation amount, the push rod stroke actual measurement being a quantity measured by a brake pedal push rod stroke sensor of the vehicle, and the push rod stroke calculation amount being a quantity measured by a brake pedal push rod stroke sensor of the vehicle; the push rod stroke calculation amount is the amount calculated according to the brake master cylinder pressure of the vehicle and a preset mapping relation; and compensating and correcting the quantity measured by the brake pedal push rod stroke sensor according to the deviation to obtain the brake pedal push rod stroke correction quantity. The invention further provides a device, a vehicle and a storage medium. According to the brake pedal push rod stroke amount correction method, the stroke amount measured by the brake pedal push rod stroke sensor can be corrected, so that the influence of external factors on the stroke amount measured by the brake pedal push rod stroke sensor is corrected, and then the consistency of the braking requirement calculated by the vehicle DBR function and the braking requirement of a driver is ensured.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a brake pedal push rod stroke correction method, device, vehicle and storage medium. Background Art

[0002] The DBR (Driver Brake Request) function is a key function of the vehicle's brake-by-wire system. This function calculates the driver's braking demand based on the travel detected by the brake pedal push rod travel sensor and the preset brake pedal characteristic curve. The vehicle's brakes generate corresponding brake pressure based on the braking demand calculated by the DBR function, so that the vehicle generates the braking force expected by the driver.

[0003] Vehicles equipped with the DBR function have the following technical problems during use: During actual use of the vehicle, affected by external factors such as the vehicle environment, mechanical wear, vibration and collision, the brake pedal push rod travel sensor may detect deviations in the brake pedal push rod travel, which in turn leads to deviations in the braking demand calculated by the DBR function, causing the braking force generated by the vehicle to be inconsistent with the driver's expectations. Summary of the invention

[0004] The purpose of the present invention is to provide a brake pedal push rod stroke correction method, device, vehicle and storage medium to alleviate or eliminate at least one of the above-mentioned technical problems.

[0005] A brake pedal push rod stroke correction method according to the present invention comprises the following steps: When the vehicle meets the brake pedal push rod stroke correction condition, the deviation between the push rod stroke actual measurement and the push rod stroke calculation amount is calculated, wherein the push rod stroke actual measurement is a quantity measured by a brake pedal push rod stroke sensor of the vehicle, and the push rod stroke calculation amount is a quantity calculated according to a preset mapping relationship based on the brake master cylinder pressure of the vehicle; The amount measured by the brake pedal push rod stroke sensor is compensated and corrected according to the deviation to obtain a brake pedal push rod stroke correction amount.

[0006] Optionally, the following steps are performed in each DBR function operation cycle of each braking cycle of the vehicle: when the vehicle meets the brake pedal push rod stroke correction condition, the deviation between the actual push rod stroke measurement and the push rod stroke calculation is calculated.

[0007] Optionally, the brake pedal push rod stroke correction method includes the following steps: calculating the average value of all the deviations in the preset braking cycles of the vehicle; compensating and correcting the quantity measured by the brake pedal push rod stroke sensor based on the deviations includes the following steps: using the average value as the correction amount to compensate and correct the quantity measured by the brake pedal push rod stroke sensor.

[0008] Optionally, the preset braking cycle is multiple braking cycles.

[0009] Optionally, the brake pedal push rod stroke correction method includes the following steps: when it is identified that the brake pedal of the vehicle is pressed, determining whether the vehicle's brake master cylinder pressure, the vehicle's brake pedal push rod speed and the vehicle's ambient temperature meet preset conditions; if so, determining that the vehicle meets the brake pedal push rod stroke correction conditions.

[0010] Optionally, the step of determining whether the brake master cylinder pressure of the vehicle, the brake pedal push rod speed of the vehicle and the ambient temperature of the vehicle meet preset conditions is performed once in each DBR function operation period of each braking cycle of the vehicle.

[0011] Optionally, the brake pedal push rod stroke correction method includes the following steps: calculating the braking demand of the vehicle based on the brake pedal push rod stroke correction amount.

[0012] The present invention also proposes a device, comprising: The first module is used to calculate the deviation between the actual push rod stroke measurement and the push rod stroke calculation amount when the vehicle meets the brake pedal push rod stroke correction condition, wherein the push rod stroke actual measurement is a quantity measured by a brake pedal push rod stroke sensor of the vehicle, and the push rod stroke calculation amount is a quantity calculated according to a preset mapping relationship based on the brake master cylinder pressure of the vehicle; The second module is used to compensate and correct the amount measured by the brake pedal push rod stroke sensor according to the deviation to obtain a brake pedal push rod stroke correction amount.

[0013] The present invention also proposes a vehicle, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the brake pedal push rod stroke correction method described in any one of the above items is implemented.

[0014] The present invention also proposes a storage medium on which a computer program is stored. When the computer program is executed by a processor, any of the above-mentioned methods for correcting the stroke of a brake pedal push rod is implemented.

[0015] The brake pedal push rod stroke correction method proposed in the present invention can correct the stroke measured by the brake pedal push rod stroke sensor to correct the influence of external factors on the stroke measured by the brake pedal push rod stroke sensor, thereby ensuring the consistency between the braking demand calculated by the vehicle DBR function and the braking demand of the driver. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a flow chart of a brake pedal push rod stroke correction method described in some embodiments; Figure 2 A flowchart of a brake pedal push rod stroke correction method described in a specific example; Figure 3 It is a brake master cylinder pressure-brake pedal push rod stroke characteristic curve of the standard brake system described in some embodiments. DETAILED DESCRIPTION

[0017] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0018] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0019] like Figure 1 A brake pedal push rod stroke correction method shown in the figure comprises the following steps: S10: when the vehicle meets the brake pedal push rod stroke correction condition, calculating the deviation between the push rod stroke actual measurement and the push rod stroke calculation, the push rod stroke actual measurement is a quantity measured by the brake pedal push rod stroke sensor of the vehicle, and the push rod stroke calculation is a quantity calculated according to a preset mapping relationship based on the brake master cylinder pressure of the vehicle; S20: Compensating and correcting the amount measured by the brake pedal push rod stroke sensor according to the deviation to obtain a brake pedal push rod stroke correction amount.

[0020] By adopting the above-mentioned brake pedal push rod stroke correction method, the push rod stroke calculation amount is calculated using the vehicle's brake master cylinder pressure and the preset mapping relationship. With the push rod stroke calculation amount as a reference, the deviation of the actual measurement of the push rod stroke can be calculated. Based on the deviation, the amount measured by the brake pedal push rod stroke sensor is compensated and corrected, and the influence of external factors on the stroke measured by the brake pedal push rod stroke sensor can be corrected, thereby obtaining a more accurate brake pedal push rod stroke correction amount. The braking force calculated using the more accurate brake pedal push rod stroke correction amount can be better consistent with the braking force of the standard brake system, which can ensure the consistency between the braking demand calculated by the vehicle's DBR (Driver Brake Request) function and the driver's braking demand.

[0021] In a specific implementation, the preset mapping relationship may be a mapping relationship between the brake master cylinder pressure and the brake pedal push rod stroke.

[0022] In some embodiments, the following steps are performed in each DBR function operation cycle of each braking cycle of the vehicle: when the vehicle meets the brake pedal push rod stroke correction condition, the deviation of the push rod stroke actual measurement and the push rod stroke calculation amount is calculated. In each DBR function operation cycle of each braking cycle, it is determined whether the vehicle meets the brake pedal push rod stroke correction condition, and when the vehicle meets the brake pedal push rod stroke correction condition, the deviation of the push rod stroke actual measurement and the push rod stroke calculation amount is calculated. The deviation between the push rod stroke actual measurement and the push rod stroke calculation amount can be tracked and calculated in real time, and more deviation calculation values ​​can be obtained, so that the average value of the deviation can be used as the correction amount for subsequent use.

[0023] A braking cycle refers to the process from the driver starting to step on the brake pedal to the driver completely releasing the brake pedal. There are multiple DBR function operation cycles in one braking cycle. The DBR function operation cycle is usually a preset value. For example, the DBR function operation cycle can be set to 5ms.

[0024] In some embodiments, the brake pedal push rod stroke correction method includes the following steps: calculating the average value of all deviations in the preset braking cycle of the vehicle; compensating and correcting the amount measured by the brake pedal push rod stroke sensor according to the deviation includes the following steps: using the average value as the correction amount, compensating and correcting the amount measured by the brake pedal push rod stroke sensor. By adopting the above technical solution, the average value of multiple deviation calculation values ​​obtained by multiple calculations is used as the correction amount for compensation correction, which can reduce the influence of random errors and improve the accuracy of compensation correction.

[0025] In specific implementation, in order to reduce the influence of random errors and improve the accuracy of compensation correction, the preset number of braking cycles is multiple braking cycles. For example, the preset number of braking cycles is 5 braking cycles.

[0026] As a specific example, calculating the average value of all deviations in multiple braking cycles of a vehicle includes the following steps: calculating the average value of all deviations in each braking cycle, recorded as a first average value, calculating the average value of all first average values ​​of multiple braking cycles, recorded as a second average value, and the second average value is the average value of all deviations in multiple braking cycles.

[0027] In some embodiments, the brake pedal push rod stroke correction method includes the following steps: when it is recognized that the brake pedal of the vehicle is stepped on, it is determined whether the brake master cylinder pressure of the vehicle, the brake pedal push rod speed of the vehicle and the ambient temperature of the vehicle meet the preset conditions. If they do, it is determined that the vehicle meets the brake pedal push rod stroke correction condition. The brake master cylinder pressure can reflect the working state of the brake system, the brake pedal push rod speed can reflect the driver's intention, and the ambient temperature has a significant impact on multiple components of the brake system. The brake pedal push rod stroke correction is performed only when the brake master cylinder pressure of the vehicle, the brake pedal push rod speed of the vehicle and the ambient temperature of the vehicle are all in a suitable range, which can ensure the reliability of the correction. Obviously, when one or more of the brake master cylinder pressure of the vehicle, the brake pedal push rod speed of the vehicle and the ambient temperature of the vehicle do not meet the preset conditions, it is determined that the vehicle does not meet the brake pedal push rod stroke correction condition.

[0028] As a specific example, the master cylinder pressure sensor of the vehicle can be used to detect the master cylinder pressure. When the master cylinder pressure is within a preset pressure range, it is determined that the master cylinder pressure meets the preset condition. Otherwise, it is determined that the master cylinder pressure does not meet the preset condition. The preset pressure range is usually a calibrated amount. For example, the preset pressure range can be set to 3 bar to 5 bar.

[0029] As a specific example, the brake pedal push rod travel sensor can be used to indirectly detect the brake pedal push rod speed. When the brake pedal push rod speed is within a preset speed range, it is determined that the brake pedal push rod speed meets the preset condition, otherwise it is determined that the brake pedal push rod speed does not meet the preset condition. The preset speed range is usually a calibrated quantity. For example, the preset speed range can be set to -2m / s to +20m / s, where "+" represents the brake pedal pressing direction and "-" represents the brake pedal releasing direction.

[0030] As a specific example, a temperature sensor can be used to detect the current ambient temperature. When the ambient temperature is within a preset temperature range, it is determined that the ambient temperature meets the preset condition. Otherwise, it is determined that the ambient temperature does not meet the preset condition. The preset temperature range is usually a calibrated value. For example, the preset temperature range can be set to above -5°C.

[0031] In some embodiments, the determination of whether the vehicle's master cylinder pressure, the vehicle's brake pedal push rod speed, and the vehicle's ambient temperature meet preset conditions is performed once in each DBR function operation cycle of each braking cycle of the vehicle. In other words, the determination of whether to calculate the deviation between the actual push rod stroke measurement and the push rod stroke calculation is performed in each DBR function operation cycle, so that more and more accurate deviation calculation values ​​can be obtained.

[0032] In some embodiments, the brake pedal push rod stroke correction method includes the following steps: calculating the vehicle's braking demand based on the brake pedal push rod stroke correction. The brake pedal push rod stroke correction is a compensation correction. Using the brake pedal push rod stroke correction as an input for DBR function calculation can calculate a more accurate braking demand, so that the braking demand calculated by the vehicle DBR function is more consistent with the driver's braking demand.

[0033] In order to better illustrate the brake pedal push rod stroke correction method proposed in this application, the method is described below with a specific example. The brake pedal push rod stroke correction method corrects the detection amount of the brake pedal push rod stroke sensor based on the mapping relationship between the brake master cylinder pressure and the brake pedal push rod stroke. Figure 2 As shown, the brake pedal push rod stroke correction method comprises the following steps: S101: When the brake pedal is depressed, determine whether the brake pedal push rod stroke correction condition is met. If so, execute S102; if not, return and determine whether the brake pedal push rod stroke correction condition is met.

[0034] S102: Calculate the deviation between the actual measurement of the push rod stroke and the calculated amount of the push rod stroke. When a braking cycle is not completed, return to execute S101 after calculating the deviation. When a braking cycle is completed, execute S103.

[0035] S103: Calculate the average value of all calculated deviations in one braking cycle, and record it as a first average value.

[0036] The above-mentioned S101, S102 and S103 are executed cyclically until five braking cycles are completed, and then S104 is executed.

[0037] S104: Calculate the average of all first average values ​​calculated in five braking cycles, and record it as the second average value.

[0038] S201: Using the second average value as a correction value, a compensation correction is performed on the value measured by the brake pedal push rod stroke sensor to obtain a brake pedal push rod stroke correction value.

[0039] S301: Calculate the braking demand of the vehicle according to the brake pedal push rod stroke correction amount.

[0040] In specific implementation, the actual measurement of the push rod stroke is the amount measured by the vehicle's brake pedal push rod stroke sensor, and the push rod stroke calculation amount is the amount calculated according to the vehicle's brake master cylinder pressure and the preset mapping relationship. The push rod stroke calculation amount is calculated by reverse calculation using the brake master cylinder pressure, which is based on the preset mapping relationship between the brake master cylinder pressure and the brake pedal push rod stroke. The corresponding push rod stroke calculation amount is calculated based on the measured brake master cylinder pressure. The mapping relationship between the brake master cylinder pressure and the brake pedal push rod stroke can be calculated based on Figure 3 The master cylinder pressure-brake pedal push rod stroke characteristic curve of the standard brake system shown in is determined. The master cylinder pressure-brake pedal push rod stroke characteristic curve can be obtained by testing, measuring and fitting the standard brake system under static conditions.

[0041] In specific implementation, the amount measured by the brake pedal push rod travel sensor may be compensated and corrected according to the following calculation formula. The calculation formula is: Y=X-δ. Wherein, Y is the brake pedal push rod travel correction amount, X is the amount measured by the brake pedal push rod travel sensor of the vehicle, and δ is the second average value calculated in S104.

[0042] The present invention also proposes a device, comprising: The first module is used to calculate the deviation between the actual push rod stroke measurement and the push rod stroke calculation amount when the vehicle meets the brake pedal push rod stroke correction condition, the push rod stroke actual measurement is the amount measured by the brake pedal push rod stroke sensor of the vehicle, and the push rod stroke calculation amount is the amount calculated according to the vehicle's brake master cylinder pressure according to a preset mapping relationship; The second module is used to compensate and correct the amount measured by the brake pedal push rod stroke sensor according to the deviation to obtain the brake pedal push rod stroke correction amount.

[0043] In specific implementation, the first module and the second module mentioned above can be submodule units in the DBR function module of the vehicle. That is to say, the DBR function module of the vehicle can be used to implement any of the above-mentioned brake pedal push rod stroke correction methods, and the DBR function module is usually deployed in the vehicle controller. It should be noted that the above explanation of the brake pedal push rod stroke correction method embodiment is also applicable to the device of this embodiment, and will not be repeated here.

[0044] The present invention also proposes a vehicle, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, any of the above-mentioned methods for correcting the stroke of the brake pedal push rod is implemented.

[0045] The present invention also proposes a storage medium on which a computer program is stored. When the computer program is executed by a processor, any of the above-mentioned methods for correcting the stroke of a brake pedal push rod is implemented.

[0046] The above embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or changes made by those skilled in the art on the basis of the present invention are all within the protection scope of the present invention. In the description of this specification, the description of reference terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics of the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

Claims

1. A method for correcting the stroke of a brake pedal push rod, characterized in that: The following steps are involved: When the vehicle meets the brake pedal push rod stroke correction condition, the deviation between the push rod stroke actual measurement and the push rod stroke calculation amount is calculated, wherein the push rod stroke actual measurement is a quantity measured by a brake pedal push rod stroke sensor of the vehicle, and the push rod stroke calculation amount is a quantity calculated according to a preset mapping relationship based on the brake master cylinder pressure of the vehicle; The amount measured by the brake pedal push rod stroke sensor is compensated and corrected according to the deviation to obtain a brake pedal push rod stroke correction amount.

2. The brake pedal push rod stroke correction method according to claim 1, characterized in that: The following steps are performed in each DBR function operation cycle of each braking cycle of the vehicle: when the vehicle meets the brake pedal push rod stroke correction condition, the deviation between the actual push rod stroke measurement and the push rod stroke calculation is calculated.

3. The brake pedal push rod stroke correction method according to claim 2, characterized in that: The brake pedal push rod stroke correction method comprises the following steps: calculating the average value of all the deviations in a preset number of braking cycles of the vehicle; The compensating and correcting the quantity measured by the brake pedal push rod stroke sensor according to the deviation includes the following steps: using the average value as the correction amount, compensating and correcting the quantity measured by the brake pedal push rod stroke sensor.

4. The brake pedal push rod stroke correction method according to claim 3, characterized in that: The preset braking cycle is a plurality of braking cycles.

5. The brake pedal push rod stroke correction method according to claim 1, characterized in that: The brake pedal push rod stroke correction method includes the following steps: when it is recognized that the brake pedal of the vehicle is pressed, judging whether the brake master cylinder pressure of the vehicle, the brake pedal push rod speed of the vehicle and the ambient temperature of the vehicle meet preset conditions; if so, determining that the vehicle meets the brake pedal push rod stroke correction conditions.

6. The brake pedal push rod stroke correction method according to claim 5, characterized in that: The step of determining whether the master cylinder pressure of the vehicle, the brake pedal push rod speed of the vehicle and the ambient temperature of the vehicle meet preset conditions is performed once in each DBR function operation period of each braking cycle of the vehicle.

7. The brake pedal push rod stroke correction method according to claim 1, characterized in that: The brake pedal push rod stroke correction method comprises the following steps: calculating the braking demand of the vehicle according to the brake pedal push rod stroke correction amount.

8. A device, characterized in that: include: The first module is used to calculate the deviation between the actual push rod stroke measurement and the push rod stroke calculation amount when the vehicle meets the brake pedal push rod stroke correction condition, wherein the push rod stroke actual measurement is a quantity measured by a brake pedal push rod stroke sensor of the vehicle, and the push rod stroke calculation amount is a quantity calculated according to a preset mapping relationship based on the brake master cylinder pressure of the vehicle; The second module is used to compensate and correct the amount measured by the brake pedal push rod stroke sensor according to the deviation to obtain a brake pedal push rod stroke correction amount.

9. A vehicle, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the brake pedal push rod stroke correction method as described in any one of claims 1 to 7 is implemented.

10. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the brake pedal push rod stroke correction method as described in any one of claims 1 to 7 is implemented.

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