Brake pressure relief control method and control device in automatic parking process

Abstract

The invention relates to a brake pressure relief control method and device in the automatic parking process. The method comprises the following steps: starting a preset automatic parking program and switching to an intelligent driving mode when a vehicle is stably parked; calculating the actual braking force of the vehicle; judging whether a preset target braking force is reached or not; after the target braking force is reached, the pressure relief slope is calculated, and the slope reflects the change relation between the braking force and time; and controlling the brake system to perform brake pressure relief according to the pressure relief slope. The brake pressure relief control device corresponding to the brake pressure relief control method can process sensor data in real time and control a brake system. By accurately controlling brake pressure relief, the safety and stability of automatic parking are improved, and wide application prospects are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of automobile intelligent driving, and relates to a braking execution strategy in an automatic parking assistance system, in particular to a pressure relief control method during ramp parking, and a parking control device applying the method. Background Art

[0002] With the acceleration of urbanization, urban parking resources are becoming increasingly scarce, and drivers face many challenges when looking for parking spaces and parking. Especially during peak hours, the problem of parking difficulties is more prominent, which has brought great pressure to urban traffic. In order to solve this problem, automakers have developed automatic parking technology, aiming to reduce the parking burden of drivers through intelligent means and improve parking efficiency.

[0003] However, existing automatic parking systems often face some technical bottlenecks in practical applications, especially when parking in sloped parking spaces. First, current automatic parking systems often rely on fixed algorithms to determine the timing of brake pressure relief. This method has poor adaptability to different slopes and different environmental conditions, and can easily cause the vehicle to slip or shake when starting. Specifically, when the vehicle is parked on a slope, after the driver steps on the brake pedal, the system needs to quickly determine when to brake and release pressure so that the vehicle can start smoothly. However, due to the lack of real-time force balance calculation, existing technologies often cannot accurately determine the best time to release pressure.

[0004] Secondly, existing automatic parking systems often require a lot of debugging and testing to determine the appropriate parameters and algorithms when dealing with complex working conditions. This not only increases development costs, but also prolongs the time to market. In addition, when using these systems, drivers often need to intervene manually to ensure safe parking of the vehicle, which to some extent weakens the convenience and intelligence level of automatic parking technology.

[0005] In summary, the existing technology has problems such as inaccurate judgment of brake pressure relief timing, poor adaptability, and high debugging cost during automatic parking on slopes, and a new method is urgently needed to improve the stability and safety of vehicles during slope parking. Therefore, developing an automatic parking pressure relief method based on force balance can effectively solve these technical problems and improve the overall performance of the automatic parking system, which has important practical significance and application value. Summary of the invention

[0006] The present invention relates to a brake pressure relief control method during automatic parking and a parking control device using the method, aiming to improve the responsiveness and stability of a vehicle's braking system during automatic parking, particularly in parking scenarios on slopes, and to solve the problem of vehicle sliding or jolting caused by inaccurate judgment of brake pressure relief timing in the prior art.

[0007] According to a first aspect of an embodiment of the present disclosure, a brake pressure relief control method in an automatic parking process is provided, the method comprising: S1, when the vehicle stops steadily, controlling the vehicle to start a preset automatic parking program, and controlling the vehicle to switch to a preset intelligent driving mode through the automatic parking program; S2, calculating the actual braking force of the vehicle in the intelligent driving mode; S3, judging whether the vehicle reaches a preset target braking force according to the actual braking force of the vehicle; S4, if the vehicle reaches a preset target braking force, determining a pressure relief slope of the vehicle, wherein the pressure relief slope is a change relationship between the braking force and time after the vehicle reaches the preset target braking force; S5, controlling the braking system of the vehicle to perform braking pressure relief according to the calculated pressure relief slope of the vehicle.

[0008] Optionally, step S2 includes the following sub-steps: S21, obtaining the mass, acceleration, driving force of the whole vehicle and the slope component force of the gravity acting on the vehicle; S22, calculating the actual braking force of the vehicle according to the following formula: FxBrk = M * a – FxPropF - FxOffset, where M is the current vehicle mass, a is the current vehicle acceleration, FxPropF is the current vehicle driving force, and FxOffset is the slope component of the gravity acting on the vehicle.

[0009] Optionally, step S3 includes the following sub-steps: S31, real-time monitoring of the braking force of the vehicle; S32, determining whether the current braking force of the vehicle reaches a preset target braking force; S33, if the target braking force is reached, the force balance mark position is marked as "reached".

[0010] Optionally, step S4 includes the following sub-steps: S41, determining and recording the slope value of the current position of the vehicle; S42, determining whether the current working condition is uphill or non-uphill; S43, if the working condition is non-uphill, the pressure relief slope is obtained by querying a preset non-uphill working condition pressure relief slope table according to the braking force change rate of the vehicle; S44, if it is an uphill working condition, the pressure relief slope is obtained by querying a preset uphill working condition pressure relief slope table according to the braking force change rate and the ramp component of the driving force and gravity.

[0011] Optionally, the specific implementation of the sub-step S43 includes: S431, obtaining braking force change rate data under non-uphill working conditions; S432, querying the non-uphill working condition pressure relief slope table, and obtaining the corresponding pressure relief slope according to the correspondence between the preset type of vehicle working condition specific parameters and the pressure relief slope recorded in the non-uphill working condition pressure relief slope table.

[0012] Optionally, the sub-step S44 includes: S441, obtaining braking force change rate data under uphill conditions; S442, obtaining the ramp component of the driving force and gravity in an uphill working condition; S443, by querying the uphill working condition pressure relief slope table, the corresponding pressure relief slope is obtained according to the correspondence between the preset types of vehicle working condition parameters and the pressure relief slope recorded in the non-uphill working condition pressure relief slope table.

[0013] Through the above steps, the present invention can effectively improve the problem of inaccurate judgment of the timing of pressure release in the prior art, improve the stability and safety of the vehicle during slope parking, reduce potential safety hazards, and ensure smooth parking of the vehicle under complex working conditions.

[0014] According to a second aspect of an embodiment of the present disclosure, a brake pressure relief control device in an automatic parking process is provided, the device comprising: A parking start module, used to control the vehicle to start a preset automatic parking program when the vehicle is stopped, and control the vehicle to switch to a preset intelligent driving mode through the automatic parking program; A braking force calculation module, used to calculate the actual braking force of the vehicle in the intelligent driving mode; A braking force monitoring module, used to determine whether the vehicle reaches a preset target braking force based on the actual braking force of the vehicle; A pressure relief slope calculation module, used to: if the vehicle reaches a preset target braking force, calculate the pressure relief slope of the vehicle, wherein the pressure relief slope is a change relationship between the braking force and time after the vehicle reaches the preset target braking force; The brake control module is used to control the brake system of the vehicle to perform brake pressure relief according to the calculated pressure relief slope of the vehicle.

[0015] Optionally, the braking force calculation module includes: A parameter acquisition unit, used to acquire the mass, acceleration, driving force of the whole vehicle and the slope component force of the gravity acting on the vehicle; The braking force calculation unit is used to calculate the actual braking force of the vehicle according to the following formula: FxBrk = M * a – FxPropF - FxOffset, where M is the current vehicle mass, a is the current vehicle acceleration, FxPropF is the current vehicle driving force, and FxOffset is the slope component of the gravity acting on the vehicle.

[0016] Optionally, the braking force monitoring module includes: A braking force monitoring unit, used to monitor the braking force of the vehicle in real time; A braking force determination unit, used to determine whether the current braking force of the vehicle reaches a preset target braking force; The force balance marking unit is used to mark the force balance mark position as "reached" if the target braking force is reached.

[0017] Optionally, the pressure relief slope determination module includes: A slope value recording unit, used to determine and record the slope value of the current position of the vehicle; A working condition judgment unit, used to judge whether the current working condition is uphill or non-uphill; The first query unit is used to: if it is a non-uphill working condition, obtain the pressure relief slope by querying a preset non-uphill working condition pressure relief slope table; The second query unit is used to: if it is an uphill working condition, obtain the pressure relief slope by querying a preset uphill working condition pressure relief slope table according to the braking force change rate and the ramp component of the driving force and gravity.

[0018] Through this structure, the system can efficiently integrate data acquisition, actual braking force calculation, braking force monitoring and brake control to ensure the accuracy and safety of the automatic parking process.

[0019] In summary, the brake pressure relief control method and parking control device in the automatic parking process of the present invention are efficient and reliable. First, by acquiring the dynamic parameters of the vehicle in real time, the accuracy of the braking force calculation is ensured, thereby improving the response speed of the system. Secondly, the system can dynamically and intelligently adjust the pressure relief slope according to different working conditions (uphill or non-uphill). This mechanism ensures safety and stability in various environments. In addition, by scientifically judging the timing of pressure relief, the safety hazards caused by brake failure or improper pressure relief can be effectively reduced. Finally, the present invention is applicable to a variety of electric vehicles and automatic driving systems, meets the needs of future intelligent transportation development, and shows a wide range of application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative labor.

[0021] Figure 1 A flowchart of a brake pressure relief control method during automatic parking provided by one embodiment of the present application; Figure 2 It is a functional module diagram of a parking control device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] The present invention relates to a brake pressure relief control method during automatic parking, which is mainly used in the field of automobile intelligent driving, especially in the automatic parking assistant (APA). With the acceleration of urbanization, parking problems have become increasingly prominent, and automatic parking technology has emerged to improve parking efficiency and safety through intelligent means. During automatic parking, the vehicle needs to be precisely controlled in complex environments such as ramps to ensure safe parking. The present invention calculates the braking force of the vehicle in real time and then releases the brake pressure after the force balance is achieved, aiming to improve the stability and safety of the vehicle when parking on a slope and reduce the risk of accidents caused by improper operation.

[0024] In existing automatic parking technologies, when a vehicle is parked on a slope, pressure is usually released immediately after the driver releases the brake pedal. This approach has significant defects. First, premature pressure release may cause the vehicle to slide down the slope, especially when the slope is large, posing a safety hazard to the driver and surrounding pedestrians. In addition, existing technologies often require a lot of debugging for different slopes to determine the appropriate timing and parameters for pressure release, which not only consumes a lot of manpower and material resources, but also increases the complexity of the system. Finally, existing technologies are insufficient in dynamic adaptability and cannot respond to changes in different slope conditions in real time, resulting in insufficient parking stability under complex working conditions, further affecting the user experience and sense of security.

[0025] The present invention effectively solves the above shortcomings by introducing a brake pressure relief control method during automatic parking, which is specifically embodied in the following aspects. First, the present invention clarifies the principle of brake pressure relief after the vehicle reaches force balance. By calculating the driving force and required braking force of the vehicle in real time, the system can accurately determine when force balance is reached. This strategy avoids the problem of vehicle sliding down the slope due to premature pressure relief, ensures that the vehicle can remain stable when parking on a slope, and significantly improves the safety of parking. Secondly, the present invention adopts a dynamically adjusted pressure relief slope calculation method. By establishing a pressure relief slope lookup table for different slope conditions, the system can flexibly adjust the pressure relief strategy according to the slope information and vehicle status obtained in real time. This method not only reduces the debugging requirements for different slopes, but also improves the adaptability of the system under complex working conditions, ensuring that the vehicle can park stably under various slope conditions. In addition, the present invention enhances the real-time monitoring capability of the vehicle's dynamic state through the application of the force balance formula. The system can continuously track and evaluate the braking force and driving force of the vehicle during the vehicle's starting phase, thereby adjusting the control strategy in a timely manner to ensure that the best braking state is always maintained during the starting process. This real-time feedback mechanism greatly improves the accuracy of parking and reduces safety hazards caused by improper operation. Finally, the strategy of the present invention can also save a lot of time and manpower and material resources for debugging. Since the system can automatically adapt to different slope conditions, the development and maintenance costs are significantly reduced. This innovation not only improves the overall performance of the automatic parking assistance system, but also provides users with a more convenient and safe parking experience.

[0026] The embodiment of the present invention provides a brake pressure relief control method during automatic parking. Figure 1 , the method comprises the following steps: S1, start the automatic parking program: After the vehicle is completely stopped, the system starts the preset automatic parking program, through which the vehicle switches to the intelligent driving mode. All of this is to ensure that the vehicle can achieve automatic control in the subsequent parking process, reduce the driver's operating burden, and improve the safety and convenience of parking.

[0027] S2, calculate the actual braking force: In the intelligent driving mode, the system first obtains key parameters such as the current vehicle mass, acceleration, vehicle driving force and the ramp component of gravity. Then, using these parameters, the actual braking force of the vehicle is calculated by the formula FxBrk=M*a−FxPropF−FxOffset. This calculation is the basis for ensuring the smooth progress of subsequent operations and provides necessary data support for the vehicle's braking control. The step S2 may include the following operations: S21, obtain vehicle parameters: before calculating the actual braking force, the system needs to obtain the current vehicle mass, acceleration, vehicle driving force and the slope component of gravity. These parameters are the basis for subsequent calculations, ensuring that the system can accurately evaluate the vehicle status and provide necessary data support for the calculation of the actual braking force.

[0028] S22, calculate the actual braking force: the system calculates the actual braking force according to the obtained vehicle parameters through the formula FxBrk=M*a-FxPropF-FxOffset. Here, M represents the vehicle mass, a is the acceleration, FxPropF is the driving force, and FxOffset is the slope component force. This calculation result will directly affect the subsequent parking control strategy.

[0029] S3, determine whether the target braking force has been reached: the system monitors the braking force status of the vehicle in real time, and determines whether the currently calculated braking force (FxBrk) has reached the preset target braking force. If the braking force has reached the target value, the system will mark the force balance mark position as "reached", indicating that the vehicle is ready for the next operation. This process ensures the stability of the vehicle when parking and avoids safety hazards caused by insufficient braking force. Specifically, step S3 may include the following operations: S31, real-time monitoring of braking force status: During the parking process, the system needs to monitor the vehicle's braking force status in real time to ensure the stability of the vehicle during parking. This monitoring process is dynamic and can provide timely feedback on changes in the vehicle's braking force to ensure that the control strategy is adjusted at any time to adapt to the current situation.

[0030] S32, judging whether the braking force reaches the target: Based on real-time monitoring of the braking force, the system judges whether the current braking force (FxBrk) reaches the preset target braking force. This judgment is a key step to ensure that the vehicle has sufficient braking force during parking to avoid potential safety hazards.

[0031] S33, mark force balance mark: Once the system confirms that the braking force has reached the target value, the force balance mark position is marked as "reached". This mark indicates that the vehicle is in a stable state and is ready for the next step of pressure relief calculation to ensure the smooth progress of the parking process.

[0032] S4, calculate the pressure relief slope: once it is confirmed that the vehicle has reached the preset target braking force, the system will start calculating the pressure relief slope. The pressure relief slope refers to the relationship between the braking force and time after the vehicle reaches the target braking force, which specifically reflects the relationship between the braking force reduction rate and time. This calculation can help the system understand the response characteristics of the braking system during the pressure relief process and provide a basis for subsequent braking control.

[0033] S41, determining the current slope value: before calculating the pressure relief slope, the system first needs to determine the current slope value. This operation is to ensure that the subsequent pressure relief calculation is not affected by vehicle starting and road bumps, and to provide accurate slope data to support the calculation of the pressure relief slope.

[0034] S42, determine the type of working condition: the system determines whether the working condition is uphill or non-uphill according to the current slope value. This judgment is crucial for the subsequent pressure relief slope calculation, because different slope conditions will affect the change characteristics of the braking force and the choice of pressure relief strategy.

[0035] S43, obtaining the pressure relief slope of non-uphill working conditions: If it is determined to be a non-uphill working condition, the system will obtain the pressure relief slope based on the change rate of the braking force. This table lookup operation is based on a preset non-uphill working condition pressure relief slope table to ensure that the corresponding pressure relief slope values ​​under different braking force change rates can be accurately obtained. The step S43 includes the following sub-steps: S431, obtain the braking force change rate data under non-uphill conditions: Under non-uphill conditions, the system needs to obtain relevant braking force change rate data. These data are obtained through real vehicle testing and data acquisition systems, and record the response characteristics under different braking force conditions. These data will be used to find the preset pressure relief slope table to obtain the corresponding pressure relief slope value to ensure the accuracy and effectiveness of the pressure relief process.

[0036] S432, search for the non-uphill condition pressure relief slope table: The system searches for the pre-set non-uphill condition pressure relief slope table based on the acquired non-uphill condition braking force change rate data. This table was established through multiple actual vehicle tests. During the test, high-precision sensors were used to record key parameters in real time, including braking force change rate, vehicle speed, brake pedal position, road conditions, and vehicle mass and load. By recording and analyzing the braking response under different braking force change rates, the relationship between the braking force change rate and the pressure relief slope is determined, and finally a pressure relief slope table is formed. After the table is established, it is further verified by actual vehicles to ensure that it effectively reflects the performance of the braking system in actual applications, so that the system can adjust the braking control strategy according to actual conditions to achieve the best parking effect.

[0037] S44, obtaining the pressure relief slope of the uphill working condition: If it is determined to be an uphill working condition, the system will look up the two-dimensional table to obtain the pressure relief slope according to the change rate of the braking force and the ramp component of the driving force and gravity. This table lookup operation is based on a preset two-dimensional relationship table of the pressure relief slope of the uphill working condition to ensure that the pressure relief slope value under different conditions can be obtained. The step S44 includes the following sub-steps: S441, obtain uphill braking force change rate data: In uphill conditions, the system needs to obtain relevant braking force change rate data. These data are obtained through real vehicle testing, and the response characteristics under different slopes and braking force conditions are recorded to accurately obtain the pressure relief slope value under uphill conditions to ensure that the braking system can respond correctly.

[0038] S442, obtain driving force and slope force data under uphill conditions: The system also needs to obtain the driving force and slope force data of gravity under uphill conditions. These data are obtained by combining vehicle dynamics models and actual vehicle tests to ensure that the system can accurately evaluate the performance of the braking system under uphill conditions.

[0039] S443, search for the two-dimensional relationship table of the pressure relief slope of the uphill condition: the system will search for the two-dimensional relationship table of the pressure relief slope of the uphill condition based on the acquired braking force change rate and ramp force component data of the uphill condition. This table is established through a large number of real vehicle tests and data analysis. During the test, the relationship between the pressure relief slope under different braking force change rates and ramp force component conditions is recorded. Specifically, the test uses high-precision sensors to collect key parameters in real time, including braking force change rate, ramp angle, vehicle speed, and brake pedal position. Through the analysis of these data, the interaction between the braking force change rate and the ramp force component and its impact on the pressure relief slope are determined. This search process ensures that the system can dynamically adjust the braking control strategy according to different working conditions to achieve safe and stable parking operations.

[0040] The above steps successfully overcome the shortcomings of existing technologies through real-time monitoring of force balance and dynamically adjusted pressure relief strategies, improve the safety, stability and adaptability of slope parking, and provide a new solution for the development of intelligent driving technology.

[0041] Another embodiment of the present invention further provides a parking control device, which can be used to implement the automatic parking brake pressure relief control method described in the above embodiment. Figure 2 The parking control device 100 includes a parking start module 101, a braking force calculation module 102, a braking force monitoring module 103, a pressure relief slope determination module 104, and a braking control module 105, aiming to realize an efficient and safe automatic parking function.

[0042] Specifically, the parking start module 101 is used to monitor the driver's operation, confirm that the vehicle enters the parking state, and prepare to start the entire parking control process. For details, please refer to step S1 of the above method embodiment; the braking force calculation module 102 is used to perform force balance calculation according to information such as the acceleration and tilt angle of the vehicle to generate the actual braking force output of the vehicle. Through efficient computing capabilities, this module can achieve real-time response under complex working conditions and improve parking accuracy. For details, please refer to step S2 of the above method embodiment; the braking force monitoring module 103 is used to monitor the braking force of the vehicle in real time and judge the current braking force. The pressure relief slope calculation module 104 is used to calculate the corresponding pressure relief slope according to the braking force change rate of the vehicle and the current working conditions to ensure the safe start of the vehicle on the slope. For details, please refer to step S4 of the above method embodiment; the braking control module 105 is used to control the vehicle's braking system to perform pressurization and pressure relief operations according to the information from the pressure relief slope calculation module to achieve a smooth parking process. For details, please refer to step S5 of the above method embodiment.

[0043] Through the coordinated work of these five modules, the system can effectively manage the vehicle parking process to ensure safety and stability.

[0044] The above parking control device builds an intelligent automatic parking system through efficient sensors, powerful control units and flexible communication interfaces, which can realize safe and stable parking operations in various complex environments.

[0045] The brake pressure relief control method and parking control device in the automatic parking process provided by the embodiment of the present invention successfully solve the defects in the prior art. The method ensures that the brake pressure relief is performed after the vehicle reaches force balance, thereby effectively avoiding the phenomenon of the vehicle sliding or shaking on the slope, and significantly improving the safety of parking. By real-time monitoring of the braking force state of the vehicle, the system can respond quickly and adjust the control strategy to ensure stability under different working conditions. In addition, the present invention reduces the debugging requirements for different slope conditions and reduces development and maintenance costs by establishing a calculation model for the pressure relief slope. More importantly, the technology can dynamically adjust the pressure relief strategy according to the real-time acquired vehicle status and ramp conditions, thereby improving the adaptability and reliability of the system. Through these innovations, the present invention not only improves the overall functional safety of the automatic parking assistance system, but also provides a new solution for the development of intelligent driving technology, promoting technological progress in the automotive industry and improving user experience.

[0046] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the following claims. It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A brake pressure relief control method during automatic parking, characterized in that: The following steps are involved: S1, when the vehicle stops steadily, controlling the vehicle to start a preset automatic parking program, and controlling the vehicle to switch to a preset intelligent driving mode through the automatic parking program; S2, calculating the actual braking force of the vehicle in the intelligent driving mode; S3, judging whether the vehicle reaches a preset target braking force according to the actual braking force of the vehicle; S4, if the vehicle reaches a preset target braking force, determining a pressure relief slope of the vehicle, wherein the pressure relief slope is a change relationship between the braking force and time after the vehicle reaches the preset target braking force; S5, controlling the braking system of the vehicle to perform braking pressure relief according to the calculated pressure relief slope of the vehicle.

2. The brake pressure relief control method during automatic parking according to claim 1, characterized in that: The step S2 comprises the following sub-steps: S21, obtaining the mass, acceleration, driving force of the whole vehicle and the slope component force of the gravity acting on the vehicle; S22, calculating the actual braking force of the vehicle according to the following formula: FxBrk = M * a – FxPropF - FxOffset, where M is the current vehicle mass, a is the current vehicle acceleration, FxPropF is the current vehicle driving force, and FxOffset is the slope component of the gravity acting on the vehicle.

3. The brake pressure relief control method during automatic parking according to claim 1, characterized in that: The step S3 comprises the following sub-steps: S31, real-time monitoring of the braking force of the vehicle; S32, determining whether the current braking force of the vehicle reaches a preset target braking force; S33: If the target braking force is reached, the force balance mark position is marked as "reached".

4. The brake pressure relief control method during automatic parking according to claim 1, characterized in that: The step S4 comprises the following sub-steps: S41, determining and recording the slope value of the current position of the vehicle; S42, determining whether the current working condition is uphill or non-uphill; S43, if the working condition is non-uphill, the pressure relief slope is obtained by querying a preset non-uphill working condition pressure relief slope table according to the braking force change rate of the vehicle; S44, if it is an uphill working condition, the pressure relief slope is obtained by querying a preset uphill working condition pressure relief slope table according to the braking force change rate and the ramp component of the driving force and gravity.

5. The brake pressure relief control method during automatic parking according to claim 4, characterized in that: The specific implementation of the sub-step S43 includes: S431, obtaining braking force change rate data under non-uphill working conditions; S432, querying the non-uphill working condition pressure relief slope table, and obtaining the corresponding pressure relief slope according to the correspondence between the preset type of vehicle working condition specific parameters and the pressure relief slope recorded in the non-uphill working condition pressure relief slope table.

6. The brake pressure relief control method during automatic parking according to claim 4, characterized in that: The sub-step S44 comprises: S441, obtaining braking force change rate data under uphill conditions; S442, obtaining the ramp component of the driving force and gravity in an uphill working condition; S443, by querying the uphill working condition pressure relief slope table, the corresponding pressure relief slope is obtained according to the correspondence between the preset types of vehicle working condition parameters and the pressure relief slope recorded in the non-uphill working condition pressure relief slope table.

7. A brake pressure relief control device during automatic parking, characterized in that: include: A parking start module, used to control the vehicle to start a preset automatic parking program when the vehicle is stopped, and control the vehicle to switch to a preset intelligent driving mode through the automatic parking program; A braking force calculation module, used to calculate the actual braking force of the vehicle in the intelligent driving mode; A braking force monitoring module, used to determine whether the vehicle reaches a preset target braking force based on the actual braking force of the vehicle; A pressure relief slope calculation module, used to: if the vehicle reaches a preset target braking force, calculate the pressure relief slope of the vehicle, wherein the pressure relief slope is a change relationship between the braking force and time after the vehicle reaches the preset target braking force; The brake control module is used to control the brake system of the vehicle to perform brake pressure relief according to the calculated pressure relief slope of the vehicle.

8. The brake pressure relief control device in the automatic parking process according to claim 7, characterized in that: The braking force calculation module comprises: A parameter acquisition unit, used to acquire the mass, acceleration, driving force of the whole vehicle and the slope component force of the gravity acting on the vehicle; The braking force calculation unit is used to calculate the actual braking force of the vehicle according to the following formula: FxBrk = M * a – FxPropF - FxOffset, where M is the current vehicle mass, a is the current vehicle acceleration, FxPropF is the current vehicle driving force, and FxOffset is the slope component of the gravity acting on the vehicle.

9. The brake pressure relief control device in the automatic parking process according to claim 7, characterized in that: The braking force monitoring module comprises: A braking force monitoring unit, used to monitor the braking force of the vehicle in real time; A braking force determination unit, used to determine whether the current braking force of the vehicle reaches a preset target braking force; The force balance marking unit is used to mark the force balance mark position as "reached" if the target braking force is reached.

10. The brake pressure relief control device in the automatic parking process according to claim 7, characterized in that: The pressure relief slope determination module comprises: A slope value recording unit, used to determine and record the slope value of the current position of the vehicle; A working condition judgment unit, used to judge whether the current working condition is uphill or non-uphill; The first query unit is used to: if it is a non-uphill working condition, obtain the pressure relief slope by querying a preset non-uphill working condition pressure relief slope table; The second query unit is used to: if it is an uphill working condition, obtain the pressure relief slope by querying a preset uphill working condition pressure relief slope table according to the braking force change rate and the ramp component of the driving force and gravity.

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