Brake hydraulic limit adjustment method, device, equipment and storage medium

Abstract

This invention belongs to the field of vehicle control technology and discloses a method, device, equipment, and storage medium for adjusting brake hydraulic limits. This application obtains the historical maintenance duration by acquiring the reading of a timer in the vehicle when the vehicle's operating state meets the test start conditions. The maximum hydraulic limit of the vehicle's braking system is adjusted based on the historical maintenance duration, the maximum holding pressure duration, and the minimum holding time. Since the timer records the total duration of the braking system's hydraulic pressure maintenance between the initial hydraulic limit and the test hydraulic limit, and combines the historical maintenance duration, the maximum holding pressure duration, and the minimum holding time to determine whether the maximum hydraulic limit of the vehicle's braking system can be set to a higher test hydraulic limit, the braking performance of the vehicle can still be accurately tested even when the speed of the brake force drum test bench is less than the vehicle's static judgment threshold, provided that the ECU does not overheat and become damaged.

Description

Technical Field

[0001] This invention relates to the field of vehicle control technology, and in particular to a method, device, equipment and storage medium for adjusting brake hydraulic limits. Background Technology

[0002] With the increasing number of vehicles using electronic braking systems (such as electronic brake boosters), in order to avoid the risk of the braking system maintaining a high hydraulic pressure for a long time, which could lead to ECU overheating and damage to components, the maximum braking hydraulic pressure of the braking system is limited to a low level (currently 70-80 bar) when the vehicle is stationary (limited by the recognition range of wheel speed sensors, the current industry threshold for determining a stationary vehicle speed is 0.3 kph).

[0003] According to testing standards, a car's total braking force must meet the requirement of F>=60%m (where m is the total mass of the car and F is the braking force) to be considered qualified. Braking force tests are conducted on a rotating drum when a vehicle rolls off the production line, is registered, or undergoes its annual inspection.

[0004] Currently, there is no standardized speed for braking force test benches, and the speeds of these test benches vary widely. Some test benches have speeds lower than the vehicle static judgment threshold of 0.3 kph. When braking force tests are conducted on such test benches, the maximum braking hydraulic pressure of the braking system is limited, which can lead to braking force test results that do not meet regulatory requirements. This makes it impossible to accurately determine whether the actual braking performance of the vehicle meets the standards.

[0005] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0006] The main objective of this invention is to provide a method, device, equipment, and storage medium for adjusting brake hydraulic limits, aiming to solve the technical problem that the speed of the rotating test bench in the prior art makes it impossible to accurately determine whether the actual braking performance of a vehicle meets the standard.

[0007] To achieve the above objectives, the present invention provides a method for adjusting brake hydraulic pressure limits, the method comprising the following steps:

[0008] When the vehicle's operating status is detected to meet the test start conditions, the reading of the timer in the vehicle is obtained to obtain the historical maintenance duration. The timer is used to record the total duration for which the hydraulic pressure of the braking system in the vehicle is maintained between the initial hydraulic pressure limit and the test hydraulic pressure limit, wherein the test hydraulic pressure limit is greater than the initial hydraulic pressure limit.

[0009] The maximum hydraulic limit of the braking system in the vehicle is adjusted based on the historical holding time, maximum holding time, and minimum holding time per cycle.

[0010] Optionally, the step of adjusting the maximum hydraulic limit of the braking system in the vehicle based on the historical holding time, maximum holding time, and minimum holding time per cycle includes:

[0011] Check whether the vehicle is in the test pressure holding state;

[0012] If it is not already in the test holding pressure state, then the holding pressure entry time threshold is determined according to the maximum holding pressure duration and the minimum holding time in a single test.

[0013] If the historical maintenance duration is less than the pressure holding duration threshold, then the maximum hydraulic limit of the braking system in the vehicle is set as the test hydraulic limit.

[0014] Optionally, if the test pressure holding state is not already in progress, the step of determining the pressure holding entry time threshold based on the maximum pressure holding time and the minimum holding time in a single test further includes:

[0015] If the historical maintenance duration is greater than or equal to the pressure holding duration threshold, then the maximum hydraulic limit of the braking system in the vehicle is set as the initial hydraulic limit.

[0016] Optionally, after the step of detecting whether the vehicle is in the test pressure holding state, the method further includes:

[0017] If the test pressure holding state is already in place, the historical holding time is compared with the maximum holding time.

[0018] If the historical holding time is less than the maximum pressure holding time, then the maximum hydraulic limit of the braking system in the vehicle is set as the test hydraulic limit.

[0019] If the duration of the historical maintenance is greater than or equal to the duration of the maximum pressure holding, then the maximum hydraulic limit of the braking system in the vehicle is set as the initial hydraulic limit.

[0020] Optionally, before the step of detecting whether the vehicle is in a pressure-holding state when the vehicle's operating state meets the test start conditions, the method further includes:

[0021] The vehicle's operating status is obtained, including vehicle speed, vehicle gear, and electronic parking status.

[0022] If the vehicle speed is less than the vehicle static judgment threshold, the vehicle is in neutral (N) gear, and the electronic parking brake is in the released state, then the vehicle's operating state is determined to meet the test start conditions.

[0023] Optionally, the step of determining that the vehicle's operating state meets the test start conditions if the vehicle's speed is less than the vehicle static determination threshold, the vehicle is in neutral (N) gear, and the electronic parking brake is in the released state includes:

[0024] If the vehicle speed is less than the vehicle static judgment threshold, the vehicle is in neutral (N) gear, and the electronic parking brake is in the released state, then it is detected whether the vehicle has triggered an emergency braking event in the current driving cycle.

[0025] If no emergency braking event has been triggered, the vehicle's operating status is determined to meet the test start conditions.

[0026] Optionally, the step of determining that the vehicle's operating state meets the test start conditions if no emergency braking event has been triggered includes:

[0027] If no emergency braking event has been triggered, then check whether the vehicle's overall acceleration has fluctuated;

[0028] If fluctuations occur, it is determined that the vehicle's operating status meets the test start conditions.

[0029] Furthermore, to achieve the above objectives, the present invention also proposes a brake hydraulic pressure limit adjustment device, which includes the following modules:

[0030] The detection module is used to obtain the reading of the timer in the vehicle when the vehicle's operating state meets the test start conditions, and to obtain the historical maintenance duration. The timer is used to record the total duration for which the hydraulic pressure of the braking system in the vehicle is maintained between the initial hydraulic pressure limit and the test hydraulic pressure limit, wherein the test hydraulic pressure limit is greater than the initial hydraulic pressure limit.

[0031] The adjustment module is used to adjust the maximum hydraulic limit of the braking system in the vehicle based on the historical holding time, maximum holding time, and minimum holding time per cycle.

[0032] Furthermore, to achieve the above objectives, the present invention also proposes a brake hydraulic limit adjustment device, which includes: a processor, a memory, and a brake hydraulic limit adjustment program stored in the memory and executable on the processor. When the brake hydraulic limit adjustment program is executed by the processor, it implements the steps of the brake hydraulic limit adjustment method as described above.

[0033] Furthermore, to achieve the above objectives, the present invention also proposes a computer-readable storage medium storing a brake hydraulic limit adjustment program, wherein the brake hydraulic limit adjustment program, when executed, implements the steps of the brake hydraulic limit adjustment method as described above.

[0034] This invention obtains the historical holding time by acquiring the timer reading when the vehicle's operating state meets the test start conditions. Based on the historical holding time, maximum pressure holding time, and minimum holding time, the maximum hydraulic limit of the vehicle's braking system is adjusted. Since the timer records the total duration of the braking system's hydraulic pressure between the initial and test hydraulic limits, and this data, combined with the historical holding time, maximum pressure holding time, and minimum holding time, determines whether the maximum hydraulic limit of the vehicle's braking system can be set to a higher test hydraulic limit, the invention ensures accurate testing of the vehicle's braking performance even when the braking force drum test bench speed is below the vehicle's static judgment threshold, provided the ECU does not overheat and suffer damage. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of an electronic device in the hardware operating environment involved in the embodiments of the present invention;

[0036] Figure 2 This is a flowchart illustrating the first embodiment of the brake hydraulic limit adjustment method of the present invention;

[0037] Figure 3 This is a flowchart illustrating the second embodiment of the brake hydraulic limit adjustment method of the present invention;

[0038] Figure 4 This is a schematic diagram of the depth-pressure relationship according to an embodiment of the present invention;

[0039] Figure 5 This is a schematic diagram of a timer accumulation rule according to an embodiment of the present invention;

[0040] Figure 6 This is a flowchart illustrating the third embodiment of the brake hydraulic limit adjustment method of the present invention;

[0041] Figure 7 This is a schematic diagram of the hydraulic limit adjustment logic according to an embodiment of the present invention;

[0042] Figure 8 This is a structural block diagram of the first embodiment of the brake hydraulic limit adjustment device of the present invention.

[0043] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0044] It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0045] Reference Figure 1 , Figure 1This is a schematic diagram of the brake hydraulic limit adjustment device for the hardware operating environment involved in the embodiments of the present invention.

[0046] like Figure 1 As shown, the electronic device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen or an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wireless-Fidelity (Wi-Fi) interface). The memory 1005 may be high-speed random access memory (RAM) or stable non-volatile memory (NVM), such as a disk drive. The memory 1005 may also optionally be a storage device independent of the aforementioned processor 1001.

[0047] Those skilled in the art will understand that Figure 1 The structure shown does not constitute a limitation on the electronic device and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0048] like Figure 1 As shown, the memory 1005, which serves as a storage medium, may include an operating system, a network communication module, a user interface module, and a brake hydraulic limit adjustment program.

[0049] exist Figure 1 In the electronic device shown, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the electronic device of the present invention can be set in the brake hydraulic limit adjustment device. The electronic device calls the brake hydraulic limit adjustment program stored in the memory 1005 through the processor 1001 and executes the brake hydraulic limit adjustment method provided in the embodiment of the present invention.

[0050] This invention provides a method for adjusting brake hydraulic pressure limits, referring to... Figure 2 , Figure 2 This is a flowchart illustrating the first embodiment of a brake hydraulic limit adjustment method according to the present invention.

[0051] In this embodiment, the brake hydraulic limit adjustment method includes the following steps:

[0052] Step S10: When the vehicle's operating status is detected to meet the test start conditions, obtain the reading of the timer in the vehicle to obtain the historical maintenance duration.

[0053] It should be noted that the executing entity in this embodiment can be the brake hydraulic limit adjustment device (hereinafter referred to as the limit adjustment device) or the vehicle itself. The limit adjustment device can be a controller in the vehicle (such as an ECU controller) or other devices that can achieve the same or similar functions. This embodiment does not limit this. In this embodiment and the following embodiments, the limit adjustment device is used as an example to illustrate the brake hydraulic limit adjustment method of the present invention.

[0054] It should be noted that the timer can be used to record the total duration for which the hydraulic pressure of the vehicle's braking system remains between the initial hydraulic pressure limit and the test hydraulic pressure limit. The initial hydraulic pressure limit is the maximum braking hydraulic pressure limit set by the braking system manufacturer when the vehicle is stationary, to protect the vehicle hardware. The test hydraulic pressure limit is the maximum hydraulic pressure limit set to ensure the vehicle can be tested normally. It can be preset by the vehicle manufacturer or the personnel in charge of the limit adjustment equipment according to the braking system specifications, for example, setting the test hydraulic pressure limit to around 100 bar. The test hydraulic pressure limit is greater than the initial hydraulic pressure limit.

[0055] It should be understood that if the vehicle's operating status meets the test start conditions, it means that the vehicle is currently being tested on the wheel hub. Even in the test state, it is necessary to avoid overheating and damage to the ECU. It is impossible to keep the maximum hydraulic limit of the braking system at a high value indefinitely. In this case, in order to determine whether the maximum hydraulic limit of the braking system can be adjusted to a higher value, the reading of the timer in the vehicle can be obtained and the obtained reading can be used as the historical maintenance duration.

[0056] Step S20: Adjust the maximum hydraulic limit of the braking system in the vehicle based on the historical holding time, maximum holding time, and minimum holding time per cycle.

[0057] It should be noted that the maximum pressure holding time can be the maximum duration during which the brake hydraulic pressure is allowed to exceed the initial hydraulic pressure limit during a single driving cycle of the vehicle. A single driving cycle refers to the process from power-on to power-off. The maximum pressure holding time can be set by the administrator of the limit adjustment device according to actual needs. To ensure that multiple braking force tests can be performed during a single driving cycle and that the ECU does not overheat, the maximum pressure holding time can be set between 300 and 600 seconds.

[0058] It should be noted that the minimum holding time per instance is the shortest time that the vehicle can maintain after entering the braking force test state to ensure sufficient braking force test time. In order to avoid the timer T reaching the limit t1 quickly after the vehicle is accidentally entered into the static braking force test state by general users, resulting in a short holding time and causing brake hydraulic pressure relief when exiting the static braking force test state, which would interfere with the user's driving, the minimum holding time per instance can be set to about 100 seconds.

[0059] In a specific implementation, adjusting the maximum hydraulic limit of the braking system in the vehicle based on the historical holding time, maximum pressure holding time, and minimum holding time can be achieved by combining the historical holding time, maximum pressure holding time, and minimum holding time to determine whether the vehicle can still support setting the maximum hydraulic limit higher, thereby adjusting the maximum hydraulic limit of the braking system in the vehicle.

[0060] This embodiment obtains the historical holding time by acquiring the timer reading when the vehicle's operating state meets the test start conditions. Based on the historical holding time, maximum pressure holding time, and minimum holding time, the maximum hydraulic limit of the vehicle's braking system is adjusted. Since the timer records the total duration of the braking system's hydraulic pressure between the initial and test hydraulic limits, and combines the historical holding time, maximum pressure holding time, and minimum holding time to determine whether the maximum hydraulic limit of the vehicle's braking system can be set to a higher test hydraulic limit, the braking performance can still be accurately tested even when the speed of the braking force test bench is less than the vehicle's static judgment threshold, provided the ECU does not overheat and become damaged. This ensures that the vehicle's braking force test results are not affected by the speed of the test bench, and that braking force test requirements can be met without increasing the vehicle's braking system specifications. This avoids excessive performance in the vehicle's braking system, reduces vehicle cost waste, and eliminates the need to modify the test bench, saving costs for the factory and testing institutions.

[0061] refer to Figure 3 , Figure 3 This is a flowchart illustrating a third embodiment of a brake hydraulic limit adjustment method according to the present invention.

[0062] Based on the first embodiment described above, step S20 of the brake hydraulic limit adjustment method in this embodiment includes:

[0063] Step S201: Detect whether the vehicle is in the test pressure holding state.

[0064] It should be noted that detecting whether a vehicle is in the test pressure holding state can be done by obtaining the current brake hydraulic pressure value of the vehicle's braking system and checking whether the current brake hydraulic pressure value is between the initial hydraulic pressure limit and the test hydraulic pressure limit. If it is, the vehicle is determined to be in the test pressure holding state; if it is not, the vehicle is determined not to be in the test pressure holding state.

[0065] Step S202: If it is not already in the test pressure holding state, then determine the pressure holding entry time threshold according to the maximum pressure holding time and the minimum holding time per time.

[0066] Understandably, if the vehicle is not already in the test pressure holding state, it is necessary to determine whether the vehicle can enter the test pressure holding state. At this time, the pressure holding entry time threshold can be determined based on the maximum pressure holding time and the minimum holding time in a single instance, so as to make further judgments.

[0067] Among them, determining the holding pressure entry time threshold based on the maximum holding pressure duration and the minimum holding time can be done by subtracting the minimum holding time from the maximum holding pressure duration and using the calculated difference as the holding pressure entry time threshold.

[0068] In practical use, the administrator of the limit adjustment device may not set a minimum holding time for a single operation, but instead directly set the holding time threshold in the limit adjustment device. Of course, if necessary, the administrator of the limit adjustment device may also pre-set the maximum holding time, the minimum holding time for a single operation, and the holding time threshold in the limit adjustment device to reduce the calculation process of the limit adjustment device. This embodiment does not impose any restrictions on this.

[0069] Step S203: If the historical maintenance duration is less than the pressure holding duration threshold, then the maximum hydraulic limit of the braking system in the vehicle is set as the test hydraulic limit.

[0070] Understandably, if the historical holding time is less than the pressure holding time threshold, it means that the duration of the vehicle entering the test pressure holding state in the current driving cycle is still relatively short. In this case, the maximum hydraulic limit of the braking system in the vehicle can be set as the test hydraulic limit.

[0071] If the maximum hydraulic pressure limit of the vehicle's braking system is set as the test hydraulic pressure limit, then if the brake pedal is pressed deeply, the brake hydraulic pressure of the braking system will gradually increase as the pedal depth increases. Once the brake hydraulic pressure exceeds the initial hydraulic pressure limit, the vehicle's timer will start timing, and the vehicle's braking system will enter the test pressure holding state (also known as the static braking force test state). After that, as the brake pedal depth gradually increases, the brake hydraulic pressure of the braking system can reach the maximum test hydraulic pressure limit.

[0072] To prevent the vehicle's ECU from overheating and being damaged, this embodiment may further include the following after step S202:

[0073] If the historical maintenance duration is greater than or equal to the pressure holding duration threshold, then the maximum hydraulic limit of the braking system in the vehicle is set as the initial hydraulic limit.

[0074] It should be noted that if the historical holding time is greater than or equal to the pressure holding time threshold, it means that the duration of the vehicle's test pressure holding state has been relatively long. If the maximum hydraulic limit of the braking system is set to the test hydraulic limit, it may cause the vehicle's ECU to overheat and be damaged. In this case, the vehicle can no longer enter the test pressure holding state in the current driving cycle. Therefore, the maximum hydraulic limit of the braking system in the vehicle is set to the initial hydraulic limit.

[0075] In practice, if the historical holding time is greater than or equal to the holding time threshold, and the vehicle needs to enter the test holding state again, the vehicle needs to be powered off to reset the timer reading to zero, and then powered on again. This avoids overheating and damage to the ECU while ensuring that the holding time in the static braking force test state is sufficient to complete the braking force test. At the same time, it avoids the situation where the vehicle acceleration sensor malfunctions and mistakenly enters the static braking force test state, causing the timer reading to quickly reach the maximum holding time, resulting in an excessively short holding time. This would cause the brake hydraulic pressure to be released when exiting the static braking force test state, interfering with the user's actual driving.

[0076] In this embodiment, after step S201, the following may also be included:

[0077] If the test pressure holding state is already in place, the historical holding time is compared with the maximum holding time.

[0078] If the historical holding time is less than the maximum pressure holding time, then the maximum hydraulic limit of the braking system in the vehicle is set as the test hydraulic limit.

[0079] If the duration of the historical maintenance is greater than or equal to the duration of the maximum pressure holding, then the maximum hydraulic limit of the braking system in the vehicle is set as the initial hydraulic limit.

[0080] It should be noted that if the vehicle is already in the test pressure holding state, it means that the brake hydraulic pressure value of the vehicle's braking system is between the initial hydraulic pressure limit and the test hydraulic pressure limit (i.e., greater than the initial hydraulic pressure limit and less than or equal to the test hydraulic pressure limit). In order to avoid ECU overheating and damage, it is necessary to determine whether the vehicle can maintain the test pressure holding state. Therefore, the historical holding time can be compared with the maximum holding time.

[0081] In actual use, if the historical holding time is less than the maximum holding time, it means that the duration of the test holding state in the current driving cycle has not reached the maximum allowable duration. The vehicle can continue to maintain the test holding state. Therefore, the maximum hydraulic limit of the braking system in the vehicle can be set as the test hydraulic limit. Since the braking hydraulic value of the braking system is between the initial hydraulic limit and the test hydraulic limit in the test holding state, the braking hydraulic value of the braking system can continue to remain unchanged.

[0082] If the historical holding time is greater than or equal to the maximum holding time, it means that the vehicle has maintained the test holding state for the maximum allowable duration in the current driving cycle. If the vehicle continues to maintain the test holding state, it may cause the ECU to overheat and be damaged. To avoid this phenomenon, the maximum hydraulic limit of the braking system in the vehicle can be set to the initial hydraulic limit. Since the braking hydraulic value of the braking system is between the initial hydraulic limit and the test hydraulic limit in the test holding state, if the maximum hydraulic limit of the braking system in the vehicle is adjusted to the initial hydraulic limit, the braking system will release pressure, thereby reducing the braking hydraulic value to be consistent with the initial hydraulic limit.

[0083] To facilitate understanding, we will now combine... Figure 4 and 5 This explanation does not limit the scope of this solution. Figure 4 This is a schematic diagram of the depth-pressure relationship in this embodiment. Figure 5 This is a schematic diagram of the timer accumulation rule in this embodiment.

[0084] like Figure 4 As shown, the maximum hydraulic limit in this embodiment can be divided into two types according to the vehicle state. The maximum hydraulic limit corresponding to the static braking force test state (i.e., the state used to deal with the low speed of the drum during the test) is the test hydraulic limit c. The maximum hydraulic limit corresponding to the normal static pressure build-up state (i.e., the mode set by the brake system manufacturer when the vehicle is stationary) is the initial hydraulic limit a. The brake hydraulic value of the brake system is proportional to the brake pedal depth. As the brake pedal depth increases, the brake hydraulic value of the brake system will gradually increase until it reaches the maximum hydraulic limit.

[0085] like Figure 5As shown, when the vehicle is stationary, in neutral (N) gear, and the electronic parking brake is released, if the brake pedal is pressed, the brake fluid pressure gradually increases with the depth of pedal application. Once the brake fluid pressure exceeds the initial value 'a', the timer starts counting. Subsequently, with further pressure on the brake pedal, the brake fluid pressure gradually increases to the test limit value 'c'. During the test, the brake fluid pressure remains constant at 'c', and the timer continues counting. After the test, when the brake pedal is released, the brake fluid pressure gradually decreases. The pressure decreases to less than 'a'. Afterwards, the timer will stop timing, and the test will be conducted again. After the brake hydraulic pressure value exceeds 'a', the timer will continue to accumulate until the cumulative reading of the timer reaches the maximum holding pressure duration 't1'. Then, the timer will stop timing and maintain the reading unchanged. The vehicle will not be able to continue to enter the test holding pressure state. At this time, the vehicle will set the maximum hydraulic limit of the braking system to the initial hydraulic limit. The vehicle will depressurize and reduce the brake hydraulic pressure value to 'a'. Then, when the brake pedal is released, the vehicle's brake hydraulic pressure value will gradually decrease to 0 as the brake pedal is pressed deeper. After that, if the vehicle is powered off, the timer reading will be cleared to zero.

[0086] This embodiment detects whether the vehicle is already in the test pressure holding state. If it is not in the test pressure holding state, a pressure holding entry time threshold is determined based on the maximum pressure holding time and the minimum holding time for a single test. If the historical holding time is less than the pressure holding entry time threshold, the maximum hydraulic limit of the braking system in the vehicle is set as the test hydraulic limit. Because the historical holding time is compared with the pressure holding entry time threshold when the vehicle is not in the test pressure holding state, and the maximum hydraulic limit of the braking system in the vehicle is adjusted according to the comparison result, it is possible to ensure that the braking force test can be performed completely every time the test pressure holding state is entered.

[0087] refer to Figure 6 , Figure 6 This is a flowchart illustrating a third embodiment of a brake hydraulic limit adjustment method according to the present invention.

[0088] Based on the first embodiment described above, the brake hydraulic limit adjustment method of this embodiment further includes, before step S10:

[0089] Step S01: Obtain the operating status of the vehicle.

[0090] It should be noted that the vehicle's operating status can include information such as vehicle speed, gear position, and electronic parking brake status. Specifically, vehicle speed can be determined by reading the vehicle's wheel speed and considering the wheel speed and wheel specifications.

[0091] Step S02: If the vehicle speed is less than the vehicle static judgment threshold, the vehicle gear is in N gear, and the electronic parking brake is in the released state, then it is determined that the vehicle's operating state meets the test start conditions.

[0092] It should be noted that the inability to accurately determine whether a vehicle's actual braking performance meets the standard only occurs when the speed on certain wheel-turning test benches is less than the vehicle's static judgment threshold. During the wheel-turning test, the vehicle is in neutral (N) and the electronic parking brake is released. Therefore, the vehicle's operating state is only considered to meet the test start conditions when the vehicle speed is less than the static judgment threshold, the vehicle is in neutral (N), and the electronic parking brake is released. This ensures the identification of static wheel-turning test scenarios and distinguishes them from actual user driving scenarios, minimizing the impact on actual users.

[0093] Furthermore, to reduce misjudgment, step S02 in this embodiment may include:

[0094] If the vehicle speed is less than the vehicle static judgment threshold, the vehicle is in neutral (N) gear, and the electronic parking brake is in the released state, then it is detected whether the vehicle has triggered an emergency braking event in the current driving cycle.

[0095] If no emergency braking event has been triggered, the vehicle's operating status is determined to meet the test start conditions.

[0096] It should be noted that the current driving cycle can be the entire driving cycle from when the vehicle is powered on to the present moment. If the vehicle performs emergency braking, after the vehicle comes to a stop, the user may keep the brake pedal firmly depressed due to emotions such as tension. At this time, the vehicle speed will be less than the vehicle's static judgment threshold, the vehicle will be in neutral (N) gear, and the electronic parking brake will be released.

[0097] To avoid misjudgment during emergency braking, the maximum hydraulic pressure limit of the braking system is set relatively high. When the vehicle speed is detected to be less than the vehicle static judgment threshold, the vehicle is in neutral (N) gear, and the electronic parking brake is released, it can also detect whether the vehicle has triggered an emergency braking event in the current driving cycle. If an emergency braking event has been triggered, it can be determined that the vehicle's operating state does not meet the test start conditions; if no emergency braking event has been triggered, it can be determined that the vehicle's operating state meets the test start conditions.

[0098] Furthermore, to more accurately identify static wheel rotation test scenarios, the step described in this embodiment of determining that the vehicle's operating state meets the test initiation conditions if no emergency braking event has been triggered may include:

[0099] If no emergency braking event has been triggered, then check whether the vehicle's overall acceleration has fluctuated;

[0100] If fluctuations occur, it is determined that the vehicle's operating status meets the test start conditions.

[0101] It should be noted that under normal operating conditions, i.e., in actual user scenarios, if the vehicle is stationary and the user presses the brake pedal deeply, the vehicle acceleration will remain at a constant value. However, when tested on a swivel test bench, the vehicle acceleration will fluctuate significantly. Therefore, in order to further improve the recognition accuracy of static swivel test scenarios, after detecting that the vehicle has not triggered an emergency braking event in the current driving cycle, it is possible to further detect whether the vehicle acceleration fluctuates. If the vehicle acceleration fluctuates, it is then determined that the vehicle's operating state meets the test start conditions.

[0102] In practical use, detecting whether the vehicle's overall acceleration fluctuates can be done by detecting whether the vehicle's overall acceleration changes within a preset time period. If a change occurs, it can be determined that the vehicle's overall acceleration has fluctuated. The preset time period can be set in advance by the personnel in charge of the limit adjustment equipment according to actual needs.

[0103] In practical implementation, to accurately determine whether the vehicle acceleration has fluctuated, when a change in vehicle acceleration is detected, it can also be detected whether the magnitude of the change in vehicle acceleration exceeds a preset judgment threshold. Only when the magnitude of the change exceeds the preset judgment threshold is it determined that the vehicle acceleration has fluctuated. The preset judgment threshold can be pre-calibrated by the personnel in charge of the limit adjustment equipment according to the vehicle model.

[0104] To facilitate understanding, we will now combine... Figure 7 This explanation does not limit the scope of this solution. Figure 7 This is a schematic diagram of the hydraulic limit adjustment logic in this embodiment, as shown below. Figure 7As shown, if the vehicle is detected to be stationary (i.e., the vehicle speed is less than or equal to the vehicle static judgment threshold), the gear is in neutral (N), and the electronic parking brake is in the released state (otherwise the process ends directly), it will further check whether the current driving cycle has triggered emergency braking (otherwise the maximum hydraulic limit of the braking system is directly set to the initial hydraulic limit a, i.e., the pressure build-up limit is set to a). If emergency braking is not triggered, it will further check whether the vehicle acceleration G value fluctuates. If the vehicle acceleration fluctuates (if it does not fluctuate, the pressure build-up limit is directly set to a), it will further check whether the vehicle is conducting a braking force test pressure holding (i.e., whether the vehicle is in a test pressure holding state). If it is in a test pressure holding state, it will check whether the historical holding time T is less than the maximum holding time t1. If it is less than t1, the maximum hydraulic limit of the braking system is set to the test hydraulic limit c, and the pressure holding continues to be maintained at the limit c; if it is not less than t1, the maximum hydraulic limit of the braking system is set to the initial hydraulic limit a, and the pressure of the braking hydraulic value of the braking system is released to a.

[0105] If the vehicle is not already in the test pressure holding state, it will check whether the historical holding time T is less than the pressure holding entry time threshold t3. If it is less than t3, the maximum hydraulic limit of the braking system will be set to c (i.e., the pressure build-up limit will be set to c); if it is not less than t3, the maximum hydraulic limit of the braking system will be set to a.

[0106] In this embodiment, when determining whether the vehicle's operating status meets the test start conditions, a preliminary judgment is made based on the vehicle's speed, gear position, and electronic parking status. Subsequently, further judgments are made based on whether an emergency braking event is triggered and whether the vehicle's overall acceleration fluctuates. This ensures accurate identification of static wheel rotation test scenarios, minimizes misjudgments, and avoids impacting the user's actual vehicle use as much as possible.

[0107] Furthermore, this embodiment of the invention also proposes a storage medium storing a brake hydraulic limit adjustment program, which, when executed by a processor, implements the steps of the brake hydraulic limit adjustment method described above.

[0108] Reference Figure 8 , Figure 8 This is a structural block diagram of the first embodiment of the brake hydraulic limit adjustment device of the present invention.

[0109] like Figure 8 As shown, the brake hydraulic limit adjustment device proposed in this embodiment of the invention includes:

[0110] The detection module 10 is used to obtain the reading of the timer in the vehicle when the vehicle's operating state meets the test start conditions, and to obtain the historical maintenance duration. The timer is used to record the total duration for which the hydraulic pressure of the braking system in the vehicle is maintained between the initial hydraulic pressure limit and the test hydraulic pressure limit, wherein the test hydraulic pressure limit is greater than the initial hydraulic pressure limit.

[0111] The adjustment module 20 is used to adjust the maximum hydraulic limit of the braking system in the vehicle based on the historical holding time, the maximum holding time, and the minimum holding time in a single operation.

[0112] This embodiment obtains the historical holding time by acquiring the timer reading when the vehicle's operating state meets the test start conditions. Based on the historical holding time, maximum pressure holding time, and minimum holding time, the maximum hydraulic limit of the vehicle's braking system is adjusted. Since the timer records the total duration of the braking system's hydraulic pressure between the initial hydraulic limit and the test hydraulic limit, and combines the historical holding time, maximum pressure holding time, and minimum holding time to determine whether the maximum hydraulic limit of the vehicle's braking system can be set to a higher test hydraulic limit, the braking performance of the vehicle can still be accurately tested even when the speed of the braking force drum test bench is less than the vehicle's static judgment threshold, provided that the ECU does not overheat and become damaged.

[0113] Furthermore, the adjustment module 20 is also used to detect whether the vehicle is already in a test pressure holding state; if it is not already in a test pressure holding state, then a pressure holding entry time threshold is determined based on the maximum pressure holding time and the minimum holding time in a single instance; if the historical holding time is less than the pressure holding entry time threshold, then the maximum hydraulic limit of the braking system in the vehicle is set as the test hydraulic limit.

[0114] Furthermore, the adjustment module 20 is also used to set the maximum hydraulic limit of the braking system in the vehicle to the initial hydraulic limit if the historical maintenance duration is greater than or equal to the pressure holding entry duration threshold.

[0115] Furthermore, the adjustment module 20 is also configured to, if already in a test pressure holding state, compare the historical holding time with the maximum pressure holding time; if the historical holding time is less than the maximum pressure holding time, set the maximum hydraulic limit of the braking system in the vehicle to the test hydraulic limit; if the historical holding time is greater than or equal to the maximum pressure holding time, set the maximum hydraulic limit of the braking system in the vehicle to the initial hydraulic limit.

[0116] Furthermore, the detection module 10 is also used to acquire the operating status of the vehicle, including vehicle speed, vehicle gear, and electronic parking status; if the vehicle speed is less than the vehicle static judgment threshold, the vehicle gear is in N gear, and the electronic parking status is in the released state, then it is determined that the detected vehicle operating status meets the test start conditions.

[0117] Furthermore, the detection module 10 is also used to detect whether the vehicle has triggered an emergency braking event in the current driving cycle if the vehicle speed is less than the vehicle static judgment threshold, the vehicle gear is in N gear, and the electronic parking brake is in the released state; if no emergency braking event has been triggered, it is determined that the detected vehicle operating state meets the test start conditions.

[0118] Furthermore, the detection module 10 is also used to detect whether the vehicle's overall acceleration fluctuates if no emergency braking event has been triggered; if fluctuation occurs, it is determined that the vehicle's operating state meets the test start conditions.

[0119] It should be understood that the above are merely illustrative examples and do not constitute any limitation on the technical solutions of the present invention. In specific applications, those skilled in the art can make settings as needed, and the present invention does not impose any restrictions on this.

[0120] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of this invention. In practical applications, those skilled in the art can select some or all of the workflow to achieve the purpose of this embodiment according to actual needs, and no restrictions are imposed here.

[0121] In addition, for technical details not described in detail in this embodiment, please refer to the brake hydraulic limit adjustment method provided in any embodiment of the present invention, which will not be repeated here.

[0122] Furthermore, it should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0123] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0124] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as read-only memory (ROM) / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0125] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A brake hydraulic pressure limit value adjustment method characterized by, The brake hydraulic pressure limit value adjustment method comprises the following steps: When it is detected that the running state of the vehicle meets a test starting condition, a reading of a timer in the vehicle is obtained to obtain a historical maintenance time length, the timer being used to record a total time length during which the hydraulic pressure of the brake system in the vehicle is maintained between an initial hydraulic pressure limit value and a test hydraulic pressure limit value, the test hydraulic pressure limit value being greater than the initial hydraulic pressure limit value; The maximum hydraulic pressure limit value of the brake system in the vehicle is adjusted according to the historical maintenance time length, a maximum pressure maintaining time length and a single minimum holding time length; The step of adjusting the maximum hydraulic pressure limit value of the brake system in the vehicle according to the historical maintenance time length, the maximum pressure maintaining time length and the single minimum holding time length comprises: It is detected whether the vehicle has been in a test pressure maintaining state; If the vehicle has not been in the test pressure maintaining state, a pressure maintaining entering time length threshold value is determined according to the maximum pressure maintaining time length and the single minimum holding time length; If the historical maintenance time length is less than the pressure maintaining entering time length threshold value, the maximum hydraulic pressure limit value of the brake system in the vehicle is set as the test hydraulic pressure limit value; If the historical maintenance time length is greater than or equal to the pressure maintaining entering time length threshold value, the maximum hydraulic pressure limit value of the brake system in the vehicle is set as the initial hydraulic pressure limit value; After the step of detecting whether the vehicle has been in the test pressure maintaining state, the following steps are further included: If the vehicle has been in the test pressure maintaining state, the historical maintenance time length is compared with the maximum pressure maintaining time length; If the historical maintenance time length is less than the maximum pressure maintaining time length, the maximum hydraulic pressure limit value of the brake system in the vehicle is set as the test hydraulic pressure limit value; If the historical maintenance time length is greater than or equal to the maximum pressure maintaining time length, the maximum hydraulic pressure limit value of the brake system in the vehicle is set as the initial hydraulic pressure limit value.

2. The brake hydraulic pressure limit value adjustment method according to claim 1, characterized by, Before the step of detecting whether the vehicle has been in the test pressure maintaining state when it is detected that the running state of the vehicle meets the test starting condition, the following step is further included: The running state of the vehicle is obtained, the running state comprising a vehicle speed, a vehicle gear and an electronic parking state; If the vehicle speed of the vehicle is less than a vehicle static determination threshold value, the vehicle gear is in the N gear and the electronic parking state is in a release state, it is determined that the running state of the vehicle meets the test starting condition.

3. The brake hydraulic pressure limit value adjustment method according to claim 2, characterized by, The step of determining that the running state of the vehicle meets the test starting condition if the vehicle speed of the vehicle is less than the vehicle static determination threshold value, the vehicle gear is in the N gear and the electronic parking state is in the release state comprises: If the vehicle speed of the vehicle is less than the vehicle static determination threshold value, the vehicle gear is in the N gear and the electronic parking state is in the release state, it is detected whether the vehicle has triggered an emergency braking event in a current driving cycle; If the emergency braking event has not been triggered, it is determined that the running state of the vehicle meets the test starting condition.

4. The brake hydraulic pressure limit value adjusting method according to claim 3, characterized by, The step of determining that the running state of the vehicle meets the test starting condition if the emergency braking event has not been triggered comprises: If the emergency braking event has not been triggered, it is detected whether the vehicle acceleration of the vehicle fluctuates; If the vehicle acceleration fluctuates, it is determined that the running state of the vehicle meets the test starting condition.

5. A brake hydraulic pressure limit value adjusting device characterized by comprising: The brake hydraulic pressure limit value adjusting device comprises the following modules: a detection module, configured to, when detecting that the running state of the vehicle meets a test starting condition, acquire a reading of a timer in the vehicle, and obtain a historical maintenance duration, the timer being configured to record a total duration of maintaining the hydraulic pressure of the brake system in the vehicle between an initial hydraulic pressure limit value and a test hydraulic pressure limit value, the test hydraulic pressure limit value being greater than the initial hydraulic pressure limit value; an adjustment module, configured to adjust a maximum hydraulic pressure limit value of the brake system in the vehicle according to the historical maintenance duration, a maximum pressure maintaining duration and a single minimum holding duration; wherein the adjustment module is further configured to detect whether the vehicle has been in a test pressure maintaining state; if not, determine a pressure maintaining entering duration threshold according to the maximum pressure maintaining duration and the single minimum holding duration; if the historical maintenance duration is less than the pressure maintaining entering duration threshold, set the maximum hydraulic pressure limit value of the brake system in the vehicle as the test hydraulic pressure limit value; if the historical maintenance duration is greater than or equal to the pressure maintaining entering duration threshold, set the maximum hydraulic pressure limit value of the brake system in the vehicle as the initial hydraulic pressure limit value; the adjustment module is further configured to, if the vehicle has been in the test pressure maintaining state, compare the historical maintenance duration with the maximum pressure maintaining duration; if the historical maintenance duration is less than the maximum pressure maintaining duration, set the maximum hydraulic pressure limit value of the brake system in the vehicle as the test hydraulic pressure limit value; if the historical maintenance duration is greater than or equal to the maximum pressure maintaining duration, set the maximum hydraulic pressure limit value of the brake system in the vehicle as the initial hydraulic pressure limit value.

6. A brake hydraulic pressure limit value adjustment apparatus characterized by, The brake hydraulic pressure limit value adjusting device comprises a processor, a memory and a brake hydraulic pressure limit value adjusting program stored in the memory and executable on the processor, the brake hydraulic pressure limit value adjusting program being used to implement the steps of the brake hydraulic pressure limit value adjusting method according to any one of claims 1-4 when executed by the processor.

7. A computer readable storage medium characterized in that, The brake hydraulic pressure limit value adjusting program is stored in the computer readable storage medium, and the brake hydraulic pressure limit value adjusting program is used to implement the steps of the brake hydraulic pressure limit value adjusting method according to any one of claims 1-4 when executed.

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