Automatic parking control method, system, device and storage medium

Abstract

The application provides an automatic parking control method, system, device and storage medium, and belongs to the technical field of intelligent driving. The method comprises the following steps: calculating a slope value of a slope based on an instantaneous slope acceleration of a target vehicle under a normal working condition; wherein the normal working condition refers to that the change rate of the slope acceleration is not out of limit; calculating a slope idle speed target torque of the target vehicle under an idle speed working condition based on the slope value of the slope; calculating an AVH pressure threshold of the target vehicle under a current slope based on the slope value of the slope; and controlling the pressure maintaining, pressure building boosting, slow release and EPB takeover work flow of the AVH based on the slope idle speed target torque under the idle speed working condition and the AVH pressure threshold under the current slope. Through the technical scheme in the application, the safety of the automatic parking function of the vehicle can be improved.

Description

Technical Field

[0001] This invention relates to the field of intelligent driving technology, and in particular to an automatic parking control method, system, device and storage medium. Background Technology

[0002] When a vehicle is equipped with an Auto Hold system (AUTOHOLD), the driver's actions when parking the vehicle are as follows: After the ignition switch is turned ON, the driver activates the AVH function by pressing the AVH button. When the driver decelerates the vehicle to a stop, parking pressure is automatically maintained in the braking circuit. The driver does not need to depress the brake pedal to keep the vehicle stationary. If the driver wishes to move out, the brake pressure is automatically released when sufficient drive torque is reached, thus completing the parking and departure process.

[0003] However, when starting after repeated parking on a slope, the accuracy of the slope estimation is affected by the changes in the vehicle's pitch angle when the vehicle moves and stops repeatedly. Insufficient holding pressure when the AVH function is activated can cause the vehicle to roll back down the slope, posing a safety hazard.

[0004] Therefore, there is an urgent need for a technical solution that can optimize the slope problem during AVH activation and deactivation. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art, and proposes an automatic parking control method, system, device and storage medium.

[0006] In a first aspect, embodiments of the present invention provide an automatic parking control method, the method comprising:

[0007] The slope value is calculated based on the instantaneous slope acceleration of the target vehicle under normal operating conditions; where normal operating conditions refer to the slope acceleration rate not exceeding the limit.

[0008] Based on the slope value, the target torque of the target vehicle at idle speed under idling conditions is calculated.

[0009] Based on the slope value of the slope, the AVH pressure threshold of the target vehicle under the current slope is calculated;

[0010] Based on the target idle torque under idling conditions and the AVH pressure threshold under the current slope, the workflow of AVH pressure holding, pressure building and boosting, slow release and EPB takeover is controlled.

[0011] In some embodiments, calculating the slope value based on the instantaneous slope acceleration of the target vehicle under normal operating conditions includes:

[0012] Based on the slope acceleration combined with the first slope calibration table, the basic slope value under no-condition compensation is obtained; where the first slope calibration table refers to the mapping table between acceleration and slope value calibrated in bench testing;

[0013] Based on the basic slope value and the second slope calibration table, the corrected slope value after error compensation is obtained; wherein, the second slope calibration table is a correction table calibrated in the bench test to compensate for the slope at different starting stages.

[0014] The corrected slope value after error compensation is used as the final slope value.

[0015] In some embodiments, obtaining the corrected slope value after error compensation based on the base slope value and a second slope calibration table includes:

[0016] If the target vehicle is in the starting condition and in the first stage of the starting condition, the slope value of the previous cycle is used as the correction slope value.

[0017] If the target vehicle is in the starting condition and in the second stage of the starting condition, the rate of change of the slope acceleration is corrected; based on the base slope value and the corrected rate of change of the slope acceleration, the slope value corresponding to the second slope calibration table is used as the corrected slope value.

[0018] In some embodiments, calculating the target idle torque of the target vehicle under idling conditions based on the slope value includes:

[0019] The engine idle torque is obtained by continuously collecting multiple engine torque cycles under idling conditions and performing mean filtering.

[0020] Based on the engine idle torque, the slope idle torque under the slope creep condition is calculated; based on the slope idle torque, the slope resistance is obtained.

[0021] Based on the slope resistance, master cylinder pressure, and slope gradient, the target braking pressure required for parking on the slope is calculated; the amplitude of the target braking pressure is limited by the slope idle torque.

[0022] Based on the slope resistance, transmission type, and slope value, the target idle torque required for starting and releasing AVH is calculated.

[0023] In some embodiments, the calculation of the AVH pressure threshold of the target vehicle at the current slope based on the slope value includes:

[0024] When the slope value is less than or equal to the second preset slope value, a fixed pressure threshold is used as the AVH pressure threshold under the current slope.

[0025] When the slope value is less than the second preset slope value, the pressure threshold corresponding to the first pressure threshold calibration table is used as the AVH pressure threshold under the current slope based on the slope value and the first pressure threshold calibration table. The first pressure threshold calibration table refers to the mapping table between the slope value and the pressure threshold calibrated in the bench test.

[0026] In some embodiments, the process of controlling the AVH pressure holding, pressure building, slow release, and EPB takeover workflow based on the target idle torque under idling conditions and the AVH pressure threshold under the current slope includes:

[0027] When the actual master cylinder pressure of the target vehicle exceeds the AVH pressure threshold, it enters the pressure holding state and obtains the wheel cylinder hydraulic pressure required to maintain anti-rollover based on the target torque of the slope idle speed.

[0028] When the wheel slips and the accumulated pressure holding time exceeds the first preset pressure holding cycle, the pressure holding state is switched to the pressure building and boosting state, and the valve duty cycle is assigned a value based on the actual master cylinder pressure and the target master cylinder pressure.

[0029] When the target vehicle enters the slow-release state, the slow-release time is accumulated; and when the accumulated slow-release time is less than the first preset calibration time and the valve duty cycle value is less than the first preset valve duty cycle, the valve duty cycle value is reassigned in combination with the accumulated slow-release time and the throttle opening.

[0030] When the target vehicle enters the EPB takeover state, it is determined whether to exit the EPB takeover state based on the EPB clamping state and the EPB duration.

[0031] In some embodiments, the actual master cylinder pressure is calculated based on the slope value of the slope.

[0032] If the slope value of the slope is within the first slope range, the actual master cylinder pressure is calculated according to the corresponding ratio based on the master cylinder pressure corresponding to the lowest slope and the master cylinder pressure corresponding to the highest slope within the first slope range.

[0033] If the slope value of the slope exceeds the first slope range, the master cylinder pressure corresponding to the highest slope within the first slope range will be used as the actual master cylinder pressure.

[0034] Secondly, embodiments of the present invention provide an automatic parking control system, the system comprising:

[0035] The first calculation module is used to calculate the slope value of the slope based on the instantaneous slope acceleration of the target vehicle under normal operating conditions; where normal operating conditions refer to the slope acceleration rate not exceeding the limit.

[0036] The second calculation module is used to calculate the target torque of the target vehicle at idle speed on the slope based on the slope value.

[0037] The third calculation module is used to calculate the AVH pressure threshold of the target vehicle at the current slope based on the slope value of the slope.

[0038] The workflow control module is used to control the AVH pressure holding, pressure building, slow release, and EPB takeover workflow based on the target idle torque under idling conditions and the AVH pressure threshold under the current slope.

[0039] In some embodiments, the second computing module includes:

[0040] The first torque calculation unit is used to continuously collect multiple engine torque cycles under idling conditions and perform mean filtering to obtain the engine idling torque.

[0041] The second torque calculation unit is used to calculate the slope idle torque under slope creep conditions based on the engine idle torque; and to convert the slope idle torque into slope resistance.

[0042] The brake pressure calculation unit is used to calculate the target brake pressure required for parking on the slope based on the slope resistance, master cylinder pressure, and slope value; and to limit the amplitude of the target brake pressure on the slope by combining the slope idle torque.

[0043] The third torque calculation unit is used to calculate the target idle torque required for starting and releasing AVH based on the slope resistance, transmission type, and slope value of the slope.

[0044] In some embodiments, the third computing module includes:

[0045] The first threshold setting unit is used to set a fixed pressure threshold as the AVH pressure threshold under the current slope when the slope value is less than or equal to the second preset slope value.

[0046] The second threshold setting unit is used to set the AVH pressure threshold at the current slope when the slope value is less than the second preset slope value, based on the slope value and the first pressure threshold calibration table. The first pressure threshold calibration table refers to the mapping table between the slope value and the pressure threshold calibrated in the bench test.

[0047] Thirdly, embodiments of the present invention provide an electronic device, the electronic device comprising:

[0048] At least one processor; and a memory communicatively connected to the at least one processor;

[0049] The memory stores a computer program that can be executed by at least one processor, such that the at least one processor is able to perform the steps of the method according to any embodiment of the present invention.

[0050] Fourthly, embodiments of the present invention provide a computer-readable storage medium storing computer instructions that are used to cause a processor to execute the steps of any embodiment of the method of the present invention.

[0051] Compared with the prior art, the present invention has the following advantages:

[0052] The automatic parking control method provided by this invention first calculates the slope value based on the instantaneous slope acceleration of the target vehicle under normal operating conditions; then, based on the slope value, it calculates the target idle torque of the target vehicle under idling conditions; next, based on the slope value, it calculates the AVH pressure threshold of the target vehicle at the current slope; finally, based on the target idle torque under idling conditions and the AVH pressure threshold at the current slope, it controls the AVH pressure holding, pressure building, slow release, and EPB takeover workflow. Through the technical solution of this invention, different workflow stages in the automatic parking process can be controlled, preventing unexpected vehicle parking and improving the safety of the automatic parking function. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only preferred embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 A flowchart illustrating an automatic parking control method provided in an embodiment of the present invention;

[0055] Figure 2 This is a schematic diagram illustrating the motion of a vehicle traveling on a slope, provided by an embodiment of the present invention.

[0056] Figure 3 A schematic diagram of a process for calculating the slope value of a slope surface, provided for an embodiment of the present invention;

[0057] Figure 4 This is a schematic diagram of an automatic parking control system provided in an embodiment of the present invention;

[0058] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] To enable those skilled in the art to better understand the technical solutions of the present invention, exemplary embodiments of the present invention are described below in conjunction with the accompanying drawings, including various details of the embodiments of the present invention to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0061] Where there is no conflict, the various embodiments of the present invention and the features thereof may be combined with each other.

[0062] As used herein, the term “and / or” includes any and all combinations of one or more related enumerated entries.

[0063] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the stated feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded. Terms such as “connected” or “linked” are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect.

[0064] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having the meaning consistent with their meaning in the context of the relevant art and the invention, and will not be interpreted as having an idealized or overly formal meaning unless expressly so defined herein.

[0065] In the technical solution of this invention, the collection, storage, use, processing, transmission, provision, and disclosure of user personal information all comply with relevant laws and regulations and do not violate public order and good morals. The use of user data in this technical solution follows relevant national laws and regulations (e.g., the "Information Security Technology - Personal Information Security Specification"). For example: appropriate measures are taken for personal information access control; restrictions are imposed on the display of personal information; the purpose of using personal information does not exceed the scope of direct or reasonable association; and explicit identity targeting is eliminated when using personal information to avoid precisely locating a specific individual.

[0066] Before introducing the technical solution of this application, it should be noted that during the parking process, there is an unexpected parking phenomenon, which is manifested as follows: when the driver repeatedly stops and starts on the slope, the AVH hydraulic parking mechanism is activated; after the vehicle is parked on the slope, it rolls back down the slope, and the driver subconsciously steps on the brake and the vehicle automatically shifts into P gear; the EPB caliper parking locks, and the gear returns to P, resulting in the vehicle being parked unexpectedly.

[0067] The root cause of the unexpected parking was as follows: On a slope, in D gear, the driver applied the brakes to park. When the AVH activation conditions were detected, AUTOHOLD activated and maintained pressure. The AVH activation conditions were: the vehicle was stationary (vehicle speed < V, duration t) and the brake pedal was fully depressed (master cylinder pressure > threshold). However, the vehicle stationary condition determination had a flaw. The pressure built up by the depressed pedal (master cylinder pressure 23 bar) was insufficient to keep the vehicle stationary on the current slope. The vehicle did not actually come to a complete stop but instead rolled down the slope at a speed of less than 1 kph. At this point, AVH was activated and maintained pressure at the current level, but the vehicle was still rolling down the slope. After the wheel speed pulses accumulated, the AVH roll-down detection condition was triggered, and AVH switched from the activated state to EPB take over. The gear automatically returned to P gear following the EPB.

[0068] The driver only wants to step on the brake to stabilize the car, and does not need to directly engage P and lock the electronic parking brake. This is frequently triggered when starting and stopping frequently on slopes, resulting in a very poor experience, and even shocks when shifting gears on slopes and shocks to the transmission mechanism.

[0069] Based on this, this application aims to propose an optimized method for automatic parking to solve the technical problem that the vehicle's driving is restricted when it mistakenly switches from AVH activation to EPB activation caliper clamping under certain special working conditions.

[0070] Figure 1 This is a flowchart illustrating an automatic parking control method provided in an embodiment of the present invention. This method is particularly suitable for situations where the vehicle repeatedly parks and then starts on a slope. This method can be executed by an automatic parking control system, which can be implemented in software and / or hardware and can be configured in an electronic device.

[0071] like Figure 1As shown, the method specifically includes:

[0072] S1 calculates the slope value based on the instantaneous slope acceleration of the target vehicle under normal operating conditions. Normal operating conditions refer to a slope acceleration rate that does not exceed the limit.

[0073] Under abnormal operating conditions (impact, bumps, rapid acceleration and deceleration), i.e., the rate of change of slope acceleration exceeds the limit, it indicates that the vehicle is experiencing severe dynamic impact, and the acceleration signal is severely distorted. In this case, slope estimation will require additional filtering and amplitude limiting to suppress jumps, and the slope cannot be directly calculated using instantaneous values.

[0074] It is understandable that changes in slope acceleration are dynamic interference signals caused by vehicle acceleration, deceleration, and bumps; while road slope is an inherent steady-state value of the road, which remains constant for a short period of time; by filtering out the instantaneous fluctuations in acceleration, the stable and true road slope can be extracted.

[0075] Figure 2 This diagram illustrates the motion of a vehicle traveling on a slope, combined with... Figure 2 When the target vehicle is traveling under normal operating conditions (acceleration rate of change not exceeding the limit), the slope acceleration is calculated based on the vehicle's direction of travel and is expressed as: Slope Acceleration = Longitudinal Acceleration - Component of Gravitational Acceleration on the Slope. Here, the slope acceleration is denoted as Veh_ST_Slope_Acc, the longitudinal acceleration as Veh_LongAcc, and the component of gravitational acceleration on the slope as Veh_AccOnSlope.

[0076] Among them, longitudinal acceleration can be read by sensors, which includes various interferences such as slope gravity, vehicle bumps, impacts, and pitching. The signal fluctuates violently, and its rate of change will not be used as a benchmark for judging working conditions.

[0077] Furthermore, the larger the estimated slope, the greater the allowable upper limit of the rate of change of slope acceleration (Veh_ST_Slope_Acc). The purpose is to: allow vehicles to accelerate and decelerate faster on steep slopes, preventing over-filtering that would indicate abnormal operating conditions with slight acceleration; and tighten the rate of change on gentle slopes to filter out minor road imperfections.

[0078] It's important to note that longitudinal acceleration refers to the acceleration component of an object along its own longitudinal axis (i.e., the direction from front to rear of the vehicle, or the tangent to its trajectory). In automotive engineering, longitudinal acceleration corresponds to the acceleration / deceleration process of a vehicle (accelerating forward and braking backward), and its direction is parallel to the vehicle's direction of travel. Surface acceleration specifically refers to the acceleration component of an object along the surface of an inclined plane (the direction of the slope's inclination), and it only exists in scenarios involving inclined planes or ramps. When driving on a ramp, the vehicle's "surface acceleration" is the result of the combined effect of gravity and the driving force.

[0079] Figure 3A flowchart illustrating the calculation of a slope value is shown. In some embodiments, the slope value is calculated based on the instantaneous slope acceleration of the target vehicle under normal operating conditions, including:

[0080] S101, based on the slope acceleration and the first slope calibration table, the base slope value under no-condition compensation is obtained. The first slope calibration table refers to the mapping table between acceleration and slope value calibrated in the bench test.

[0081] The slope acceleration (Veh_ST_Slope_Acc) is input into the first slope calibration table, and the corresponding slope value in the first slope calibration table is used as the base slope value (g_Veh_ST_Slope_f). The first slope calibration table does not distinguish between two-wheel drive and four-wheel drive vehicles; it only performs conversions based on the vehicle's longitudinal acceleration and gravity components. The base slope value it outputs cannot distinguish the vehicle's pitch disturbance caused by the four-wheel drive chassis and has no compensation capability, thus calculating false slopes.

[0082] S102, based on the basic slope value and the second slope calibration table, obtain the corrected slope value after error compensation. The second slope calibration table is a correction table calibrated in the bench test to compensate for the slope at different starting stages.

[0083] The second slope calibration table only compensates for pitch error during start-up. It only corrects suspension lift and IMU attitude shift during the vehicle's stationary start-up phase. The calibration scenario only distinguishes between start-up and non-start-up, and does not consider the slight body pitch caused by the four-wheel drive transfer case or uneven four-wheel drive force. The false slope during four-wheel drive acceleration with heavy throttle on flat ground does not fall under the "100ms pitch error during start-up" category, and the second slope calibration table cannot correct this error; its output may still contain incorrect slope values.

[0084] In some embodiments, the corrected slope value after error compensation is obtained based on the base slope value and a second slope calibration table, including:

[0085] S1021, If ​​the target vehicle is in the starting condition and in the first stage of the starting condition, the slope value of the previous cycle shall be used as the correction slope value.

[0086] The first stage of the starting condition is set to the first 100ms of the starting condition. During this stage, the vehicle will exhibit a nose-up phenomenon. The slope estimation at this time is considered unchanged and is not used for calculation. The logic directly freezes the slope. The corrected slope value (g_Veh_CorrectedSlopeVal) maintains the valid value of the previous cycle and does not jump with the base slope value.

[0087] S1022, if the target vehicle is in the starting condition and in the second stage of the starting condition, then correct the rate of change of the slope acceleration; based on the base slope value and the corrected rate of change of the slope acceleration, use the slope value corresponding to the second slope calibration table as the corrected slope value.

[0088] The second stage of the starting condition is set to 100ms after the starting condition. The slope change rate is adjusted in stages according to the starting speed and throttle position. The basic slope value (g_Veh_ST_Slope_f) and the adjusted slope acceleration change rate are input into the second slope calibration table. The corresponding slope value in the second slope calibration table is used as the final slope value. Secondary calibration compensation is performed for the starting pitch error to smooth out the slope estimation deviation in the starting stage.

[0089] When starting uphill and lifting your head: the slope calculated by the first slope calibration table is too large. The slope is corrected downward by the second slope calibration table, that is, the corrected slope value is less than the basic slope value.

[0090] When starting downhill with the head down: the slope calculated by the first slope calibration table is too small, so the slope is corrected upward by the second slope calibration table, that is, the corrected slope value is greater than the basic slope value.

[0091] For example, assuming the vehicle's actual gradient is 8%, the process of estimating the gradient at different stages of starting uphill is specifically as follows:

[0092] During the stable and uniform speed phase: by referring to the first slope calibration table, the basic slope value is found to be 8%; without starting compensation, by referring to the second slope calibration table, the corrected slope value is found to be 8%, and the two are equal.

[0093] The first stage of the starting condition: the vehicle body pitches up, the IMU attitude deflects, and by looking up the first slope calibration table, the basic slope value is found to be 11% (artificially high); the program freezes the slope and corrects the slope value to keep it unchanged at 8%.

[0094] The second stage of the starting condition: by looking up the first slope calibration table, the basic slope value is found to be 11%; the freezing is released, the rate of change of slope acceleration is limited, and compensation is made by looking up the second slope calibration table to correct the slope value to 8%, thus offsetting the 3% false increase error in the starting condition.

[0095] S1023, the corrected slope value after error compensation is used as the final slope value.

[0096] In some embodiments, if the target vehicle is a four-wheel drive vehicle and the target vehicle is accelerating on flat ground, the slope value of the final slope is set to zero.

[0097] When a four-wheel drive vehicle accelerates hard on flat ground, the torque difference between the front and rear axles will cause slight compression / tension of the suspension, and the IMU will mistakenly identify a false slope. The first and second slope calibration tables are only calibrated for gravity slopes and starting pitch, and cannot cover the attitude interference caused by drive torque. Therefore, an independent forced zeroing logic is added at the end of the table lookup link as a supplementary compensation exclusive to four-wheel drive.

[0098] Understandably, the calibration rules and input-output mapping relationships of the first and second slope calibration tables are completely universal for both two-wheel drive and four-wheel drive vehicles. Neither table will recognize or cancel out false slopes generated by four-wheel drive acceleration on flat ground. Therefore, when the target vehicle is a four-wheel drive vehicle, the false slopes generated by the four-wheel drive vehicle must be further considered.

[0099] For example, the process of a four-wheel drive vehicle estimating the slope in different scenarios is specifically manifested as follows:

[0100] Under normal incline driving conditions (uphill / downhill, acceleration on non-flat ground): The base slope value is 10% obtained by consulting the first slope calibration table; with no disturbance during start-up, the corrected slope value is 10% obtained by consulting the second slope calibration table; without triggering the four-wheel drive reset condition, the corrected slope value of 10% is used as the final slope value. At this time, the four-wheel drive logic is not active, and the slope is calibrated entirely using the first and second slope calibration tables.

[0101] Four-wheel drive vehicle coasting on flat ground at a constant speed: There is no vehicle pitch caused by driving torque. By looking up the first slope calibration table, the basic slope value is 0. By looking up the second slope calibration table, the corrected slope value is 0. Even if four-wheel drive and flat ground are met, but there is no heavy acceleration, the forced zeroing is not triggered. The final slope value is zero, which is consistent with the forced zeroing result.

[0102] Four-wheel drive vehicle flat-ground rapid acceleration condition (special condition): Uneven distribution of four-wheel drive force, slight body lift, IMU generates interference acceleration; by looking up the first slope calibration table, the basic slope value is obtained as 4%; by looking up the second slope calibration table (no start compensation required), the corrected slope value is obtained as 4%; four-wheel drive flat-ground acceleration judgment is triggered, and the final slope value is forcibly set to zero.

[0103] S2, based on the slope value of the slope, calculates the target torque of the target vehicle at idle speed on the slope.

[0104] The triggering conditions for idling are: the vehicle is stationary, the throttle opening is less than a first preset threshold, and the gear is in D or P. This is represented as: (Vehicle stopped) && (Throttle opening % <= 1) && (Current gear = D or R), determining the vehicle's idling speed. Idle operation refers to the state where the engine runs at its lowest stable speed without outputting power.

[0105] In some embodiments, the target idle torque of the target vehicle under idling conditions is calculated based on the slope value of the slope, including:

[0106] S201 continuously collects multiple engine torque cycles under idling conditions and performs mean filtering to obtain the engine idling torque.

[0107] For example, the engine torque signal of 20 cycles after 1 second of vehicle idling is averaged to calculate the idle torque. The idle torque is then reset to zero after 2 seconds and recalculated.

[0108] Calculating the engine's base output torque at stable idling speed is the sole fundamental input for subsequent steps. Idle torque is low on flat ground, resulting in low creep torque; the required base driving force changes accordingly on steep slopes; idle torque differs between cold and warm engines, and only after applying mean filtering compensation to the idle torque will the creep torque calculation result not drift.

[0109] S202, based on the engine idle torque, calculates the slope idle torque under slope creep conditions; based on the slope idle torque, the slope resistance is obtained.

[0110] The triggering conditions for the slope creep condition are: vehicle speed less than a preset speed threshold and throttle opening less than a second preset opening threshold. This is expressed as: (vehicle speed < 2) && (throttle opening % < 2). The slope creep torque = |engine idle torque| * gear ratio / (wheel radius * vehicle mass), with a limit value ∈ [0, 8], and its sign determined by the gear.

[0111] Converting idle torque into the amount of slope resistance that a vehicle can overcome at idle speed alone serves as a bridge connecting engine torque and braking pressure.

[0112] S203 calculates the target braking pressure required for parking on the slope based on the slope resistance, master cylinder pressure, and slope value; and limits the amplitude of the target braking pressure on the slope by combining the slope idle torque.

[0113] Master cylinder pressure = Torque_Pressure conversion coefficient * 2 * Length coefficient / (Pressure coefficient * NON_ZERO (wheel radius)), where the torque_pressure conversion coefficient is denoted as TORQUE_PRESSURE_PARA_F / R, the length coefficient is denoted as Length_FACTOR, the pressure coefficient is denoted as Prs_FACTOR, and the master cylinder pressure is denoted as Fx / Rx. NON_ZERO() is a zero-reduction protection function, providing a fallback for the minimum wheel radius.

[0114] The target braking pressure for a slope is calculated as: vehicle mass * 10 * |corrected slope + equivalent slope| * vehicle parking calibration coefficient / NON_ZERO(master cylinder pressure Fx + master cylinder pressure Rx), with a limit value ∈ [0.5, 5]. When calibrating the upper and lower limits of the slope braking pressure, creep torque must be used as a reference. If the idle driving force is insufficient to overcome the slope, the target braking pressure is automatically increased to prevent the vehicle from rolling back.

[0115] Calculating the required master cylinder braking pressure to stabilize the current incline is based on the theoretical demand value of the brake hydraulic system. During the stationary phase, the vehicle is locked in place by braking pressure, and the engine only outputs basic idle torque.

[0116] S204 calculates the target idle torque required for starting and releasing AVH based on the slope resistance, transmission type, and slope value.

[0117] In some embodiments, the target idle torque required for initial AVH release is calculated, including:

[0118] S2041, when the target vehicle's transmission type is MT transmission, the initial slope idle target torque is calculated based on the slope value and transmission ratio.

[0119] Initial slope idle target torque = vehicle mass * |corrected slope| * wheel radius / MAX (gear ratio, upper gear ratio clamp). The upper gear ratio clamp is set to 10.

[0120] S2042, when the target vehicle has a CVT transmission and is on a steep slope, stationary, and in D or R gear, a fixed calibration value is used as the initial target torque for hill idling.

[0121] S2043, when the slope value of the slope is less than the first preset slope value and the target vehicle is not in R gear, or when the slope value of the slope is greater than the opposite value of the first preset slope value and the target vehicle is in R gear, the initial slope idle speed target torque is taken as the slope idle speed target torque.

[0122] The first preset slope value is set to 2. This can be expressed as: when (corrected slope < 2 && gear not in R) || (corrected slope > -2 && gear in R), the target torque for idling on the slope = CCP_VEH_SlopeTorque_Aim_THR.

[0123] If the slope value is less than the preset slope value, it is considered a slight uphill slope; if the slope value is greater than the opposite of the preset slope value, it is considered a slight downhill slope.

[0124] S2044, when the required target torque is negative and the target vehicle is not in reverse gear, the opposite value of the initial hill idling target torque is taken as the hill idling target torque.

[0125] It is understandable that when the vehicle torque sign is negative and the gear position is R, the target torque for idling on the slope is -CCP_VEH_SlopeTorque_Aim_THR.

[0126] The torque request sent to the EMS is the core instruction for preventing rollback during hill starts, and its layered logic has an internal progressive relationship. The first layer is the MT general formula: calculating the basic compensation torque using the vehicle's mass, slope, wheel radius, and transmission ratio; the second layer is the CVT special calibration logic: on steep slopes, when stationary in D / R gear, the mechanical formula is not followed, and the calibration torque is used directly (to compensate for the CVT's low-speed torque characteristic deficiency); the third layer is the general small slope threshold logic: distinguishing between forward / reverse gears and positive / negative torque, and unifying the compensation values ​​for high and low speeds on small slopes.

[0127] Calculating how much torque the engine needs to output to counteract the slope resistance and calculating the theoretical parking brake pressure are part of the power system pre-matching; calculating how much torque the engine needs to output to prevent the vehicle from rolling away when it is stationary is part of the theoretically required braking pressure.

[0128] S3, based on the slope value of the slope, calculates the AVH pressure threshold of the target vehicle under the current slope.

[0129] The corresponding pressure threshold is obtained by looking up the estimated slope value in a table.

[0130] In some embodiments, the AVH pressure threshold of the target vehicle at the current slope is calculated based on the slope value, including:

[0131] S301, when the slope value of the slope is less than or equal to the second preset slope value, a fixed pressure threshold is used as the AVH pressure threshold under the current slope.

[0132] The second preset slope value is set to 5. This can be expressed as: when the corrected slope value is ≤ 5, the pressure threshold = CCP_AVH_MCP_THR_DEEP.

[0133] S302, when the slope value is less than the second preset slope value, the pressure threshold corresponding to the first pressure threshold calibration table is used as the AVH pressure threshold under the current slope based on the slope value and the first pressure threshold calibration table. The first pressure threshold calibration table refers to the mapping table between slope values ​​and pressure thresholds calibrated in the bench test.

[0134] The second preset slope value is set to 5. This can be expressed as: when the corrected slope value > 5, the pressure threshold = pressure threshold g_AVH_IN_MCP_THR.

[0135] In some embodiments, the method further includes: setting a maximum pressure holding period, wherein when the target vehicle is in braking condition and the accumulated pressure holding time has not exceeded the maximum pressure holding period, the accumulated pressure holding time is continued and the pressure is maintained.

[0136] The maximum pressure holding period is set to 500ms. This can be represented as: vehicle braking = 1 && pressure holding time < 500ms, then maintain pressure holding. Vehicle braking is denoted as g_Veh_Braking_b, and pressure holding time is denoted as g_AVH_BrakeHoldCnt.

[0137] Setting the pressure threshold for AVH function activation / maintenance based on the slope and calculating the pressure holding time constitutes the AVH function start / stop judgment layer; determining the pressure at which AVH will intervene when the brake is applied and how long the pressure holding can be maintained are prerequisite judgment conditions for hydraulic actuation.

[0138] S4 controls the AVH pressure holding, pressure building, slow release, and EPB takeover workflow based on the target idle torque under idling conditions and the AVH pressure threshold under the current slope.

[0139] In some embodiments, based on the target idle torque under idling conditions and the AVH pressure threshold at the current slope, the workflow for controlling AVH pressure holding, pressure building, slow release, and EPB takeover is included:

[0140] S401 enters a pressure-holding state when the actual master cylinder pressure of the target vehicle exceeds the AVH pressure threshold, and obtains the wheel cylinder hydraulic pressure required to maintain anti-rollover based on the target torque at the slope idle speed.

[0141] After the target vehicle is powered on / brakes completely, it automatically enters a pressure holding phase to maintain the current hydraulic anti-rollover function of the wheel cylinders.

[0142] S402, when the wheel slips and the accumulated pressure holding time exceeds the first preset pressure holding cycle, switches from the pressure holding state to the pressure building and boosting state, and assigns a value to the valve duty cycle based on the actual master cylinder pressure and the target master cylinder pressure.

[0143] The actual master cylinder pressure is calculated based on the slope value of the slope.

[0144] If the slope value of the slope is within the first slope range, the actual master cylinder pressure is calculated according to the corresponding ratio based on the master cylinder pressure corresponding to the lowest slope and the master cylinder pressure corresponding to the highest slope within the first slope range.

[0145] If the slope value of the slope exceeds the first slope range, the master cylinder pressure corresponding to the highest slope within the first slope range will be used as the actual master cylinder pressure.

[0146] For example, the first slope range can be set to (0, 30). If |corrected slope| ∈ (0, 30), then the target master cylinder pressure = MPa_Slpoe_0 + (MPa_Slpoe_30 - MPa_Slpoe_0) * |corrected slope| / 30. If |corrected slope| > 30, then the target master cylinder pressure = MPa_Slpoe_30. Where MPa_Slpoe_0 is the master cylinder pressure when the slope is 0, and MPa_Slpoe_30 is the master cylinder pressure when the slope is 30.

[0147] The valve duty cycle is assigned a value based on the actual master cylinder pressure and the target master cylinder pressure.

[0148] If the actual master cylinder pressure is less than or equal to the target master cylinder pressure, then the fully open pressure value of the booster valve is assigned to the valve duty cycle.

[0149] For example, if the master cylinder pressure is less than or equal to the target master cylinder pressure, then the valve duty cycle is equal to the fully open pressure value of the booster valve; if the master cylinder pressure is 7 MPa, then the valve duty cycle is 1000.

[0150] S403, when the target vehicle enters the slow-reverse release state, the cumulative slow-reverse time is recorded; and when the cumulative slow-reverse time is less than the first preset calibration time and the valve duty cycle value is less than the first preset valve duty cycle, the valve duty cycle value is reassigned in combination with the cumulative slow-reverse time and the throttle opening.

[0151] The first preset valve duty cycle is set to 1000. This can be expressed as follows: if the AVH slow-exit time < calibration value && XY valve duty cycle < 1000, then the AVH slow-exit time continues to accumulate, and the XY valve duty cycle = 1 * AVH slow-exit time + A (based on throttle opening). The AVH slow-exit time is denoted as g_AVH_SlowExit_Time.

[0152] S404, when the target vehicle enters the EPB takeover state, determines whether to exit the EPB takeover state based on the EPB clamping state and the EPB duration.

[0153] If the EPB is not clamped and the EPB duration has not reached the preset EPB cycle duration, continue to accumulate the EPB duration and maintain hydraulic pressure.

[0154] If the EPB is not clamped and the EPB duration reaches the preset EPB cycle duration, but the slow retreat is not completed, the AVH slow retreat time will continue to accumulate, and the valve duty cycle value will be reassigned based on the AVH slow retreat time.

[0155] If the EPB is not clamped and the EPB duration reaches the preset EPB cycle duration, but the slow-return timing exceeds the limit, the AVH will take over and completely disengage the hydraulic parking brake.

[0156] When the EPB is clamped and the EPB duration reaches the preset EPB clamping cycle duration, the AVH brake light goes out and the ESC EPB request is cancelled.

[0157] The technical solution in this invention proposes a method for estimating slope gradient based on the instantaneous slope acceleration of the target vehicle under normal operating conditions. The method corrects the rate of change of the estimated slope value according to different stages of starting, and then obtains the corrected slope value by looking up a table. Specifically, considering that the vehicle may experience nose-up during starting, the slope estimate at this time is considered unchanged and is not used for calculation. A method for AVH pressure gradual deceleration control is also proposed, which can be matched to the magnitude of the climbing slope of the drive torque, ensuring that when the vehicle's AVH decelerates during starting, the vehicle will not experience sluggish starting due to excessively slow AVH depressurization, nor will it experience forward lurching due to excessively rapid AVH depressurization. This solves the technical problem in the prior art where, under certain special operating conditions, the vehicle mistakenly jumps from AVH activation to EPB activation caliper clamping, resulting in restricted vehicle movement.

[0158] Based on the same inventive concept, embodiments of the present invention also provide an automatic parking control system. Figure 4 This is a schematic diagram of an automatic parking control system provided in an embodiment of the present invention, as shown below. Figure 4 As shown, the system specifically includes:

[0159] The first calculation module 100 is used to calculate the slope value of the slope based on the instantaneous slope acceleration of the target vehicle under normal operating conditions; where normal operating conditions refer to the slope acceleration rate not exceeding the limit.

[0160] The second calculation module 200 is used to calculate the target torque of the target vehicle at idle speed under idling conditions based on the slope value of the slope.

[0161] The third calculation module 300 is used to calculate the AVH pressure threshold of the target vehicle at the current slope based on the slope value of the slope.

[0162] The workflow control module 400 is used to control the AVH pressure holding, pressure building, slow release, and EPB takeover workflow based on the target idle torque under idling conditions and the AVH pressure threshold under the current slope.

[0163] In some embodiments, the second computing module includes:

[0164] The first torque calculation unit is used to continuously collect multiple engine torque cycles under idling conditions and perform mean filtering to obtain the engine idling torque.

[0165] The second torque calculation unit is used to calculate the slope idle torque under slope creep conditions based on the engine idle torque; and to convert the slope idle torque into slope resistance.

[0166] The brake pressure calculation unit is used to calculate the target brake pressure required for parking on the slope based on the slope resistance, master cylinder pressure, and slope value; and to limit the amplitude of the target brake pressure on the slope by combining the slope idle torque.

[0167] The third torque calculation unit is used to calculate the target idle torque required for starting and releasing AVH based on the slope resistance, transmission type, and slope value of the slope.

[0168] In some embodiments, the third computing module includes:

[0169] The first threshold setting unit is used to set a fixed pressure threshold as the AVH pressure threshold under the current slope when the slope value is less than or equal to the second preset slope value.

[0170] The second threshold setting unit is used to set the AVH pressure threshold at the current slope when the slope value is less than the second preset slope value, based on the slope value and the first pressure threshold calibration table. The first pressure threshold calibration table refers to the mapping table between the slope value and the pressure threshold calibrated in the bench test.

[0171] The technical solutions in the embodiments of the present invention have similar beneficial effects to those described above, and will not be repeated here.

[0172] Based on the same inventive concept, embodiments of the present invention also provide an electronic device. Figure 5 This is a structural block diagram of an electronic device provided in an embodiment of the present invention. Figure 5 As shown, an embodiment of the present invention provides an electronic device including: one or more processors 101, a memory 102, and one or more I / O interfaces 103. The memory 102 stores one or more programs, which, when executed by the one or more processors, cause the one or more processors to implement any of the automatic parking control methods described in the above embodiments; the one or more I / O interfaces 103 are connected between the processor and the memory, configured to enable information interaction between the processor and the memory.

[0173] The processor 101 is a device with data processing capabilities, including but not limited to a central processing unit (CPU); the memory 102 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and flash memory (FLASH); the I / O interface (read / write interface) 103 is connected between the processor 101 and the memory 102, and can realize information interaction between the processor 101 and the memory 102, including but not limited to a data bus (BUS).

[0174] In some embodiments, the processor 101, memory 102, and I / O interface 103 are interconnected via bus 104, and thus connected to other components of the computing device.

[0175] In some embodiments, the one or more processors 101 include a field-programmable gate array.

[0176] This invention also provides a computer-readable medium. The computer-readable medium stores a computer program, which, when executed by a processor, implements the steps of any of the automatic parking control methods described in the above embodiments. The computer-readable storage medium may be volatile or non-volatile.

[0177] This invention also provides a computer program product, including computer-readable code, or a non-volatile computer-readable storage medium carrying computer-readable code. When the computer-readable code is run in the processor of an electronic device, the processor in the electronic device executes the above-described automatic parking control method.

[0178] Those skilled in the art will understand that all or some of the steps, systems, and apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software can be distributed on a computer-readable storage medium, which may include computer storage media (or non-transitory media) and communication media (or transient media).

[0179] As is known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable program instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), static random access memory (SRAM), flash memory or other memory technologies, portable compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, it is known to those skilled in the art that communication media typically contain computer-readable program instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0180] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0181] The computer program instructions used to perform the operations of this invention may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing state information from the computer-readable program instructions. This electronic circuitry can execute the computer-readable program instructions to implement various aspects of the invention.

[0182] The computer program product described herein can be implemented specifically through hardware, software, or a combination thereof. In one alternative embodiment, the computer program product is specifically embodied in a computer storage medium; in another alternative embodiment, the computer program product is specifically embodied in a software product, such as a software development kit (SDK), etc.

[0183] Various aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0184] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0185] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0186] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction, which contains one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0187] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for illustrative purposes only and should be construed as such, and is not intended to be limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

Claims

1. An automatic parking control method, characterized in that, include: The slope value is calculated based on the instantaneous slope acceleration of the target vehicle under normal operating conditions; where normal operating conditions refer to the slope acceleration rate not exceeding the limit. Based on the slope value, the target torque of the target vehicle at idle speed under idling conditions is calculated. Based on the slope value of the slope, the AVH pressure threshold of the target vehicle under the current slope is calculated; Based on the target idle torque under idling conditions and the AVH pressure threshold under the current slope, the workflow of AVH pressure holding, pressure building and boosting, slow release and EPB takeover is controlled.

2. The method according to claim 1, characterized in that, The calculation of the slope value based on the instantaneous slope acceleration of the target vehicle under normal operating conditions includes: Based on the slope acceleration combined with the first slope calibration table, the basic slope value under no-condition compensation is obtained; where the first slope calibration table refers to the mapping table between acceleration and slope value calibrated in bench testing; Based on the basic slope value and the second slope calibration table, the corrected slope value after error compensation is obtained; wherein, the second slope calibration table is a correction table calibrated in the bench test to compensate for the slope at different starting stages. The corrected slope value after error compensation is used as the final slope value.

3. The method according to claim 2, characterized in that, The process of obtaining the corrected slope value after error compensation based on the basic slope value and the second slope calibration table includes: If the target vehicle is in the starting condition and in the first stage of the starting condition, the slope value of the previous cycle is used as the correction slope value. If the target vehicle is in the starting condition and in the second stage of the starting condition, the rate of change of the slope acceleration is corrected; based on the base slope value and the corrected rate of change of the slope acceleration, the slope value corresponding to the second slope calibration table is used as the corrected slope value.

4. The method according to claim 1, characterized in that, The slope value based on the slope is used to calculate the target idle torque of the target vehicle under idling conditions, including: The engine idle torque is obtained by continuously collecting multiple engine torque cycles under idling conditions and performing mean filtering. Based on the engine idle torque, the slope idle torque under the slope creep condition is calculated; based on the slope idle torque, the slope resistance is obtained. Based on the slope resistance, master cylinder pressure, and slope gradient, the target braking pressure required for parking on the slope is calculated; the amplitude of the target braking pressure is limited by the slope idle torque. Based on the slope resistance, transmission type, and slope value, the target idle torque required for starting and releasing AVH is calculated.

5. The method according to claim 1, characterized in that, The slope value based on the slope surface is used to calculate the AVH pressure threshold of the target vehicle at the current slope, including: When the slope value is less than or equal to the second preset slope value, a fixed pressure threshold is used as the AVH pressure threshold under the current slope. When the slope value is less than the second preset slope value, the pressure threshold corresponding to the first pressure threshold calibration table is used as the AVH pressure threshold under the current slope based on the slope value and the first pressure threshold calibration table. The first pressure threshold calibration table refers to the mapping table between the slope value and the pressure threshold calibrated in the bench test.

6. The method according to claim 1, characterized in that, The workflow for controlling AVH pressure holding, pressure building, slow release, and EPB takeover, based on the target idle torque under idling conditions and the AVH pressure threshold at the current slope, includes: When the actual master cylinder pressure of the target vehicle exceeds the AVH pressure threshold, it enters the pressure holding state and obtains the wheel cylinder hydraulic pressure required to maintain anti-rollover based on the target torque of the slope idle speed. When the wheel slips and the accumulated pressure holding time exceeds the first preset pressure holding cycle, the pressure holding state is switched to the pressure building and boosting state, and the valve duty cycle is assigned a value based on the actual master cylinder pressure and the target master cylinder pressure. When the target vehicle enters the slow-release state, the slow-release time is accumulated; and when the accumulated slow-release time is less than the first preset calibration time and the valve duty cycle value is less than the first preset valve duty cycle, the valve duty cycle value is reassigned in combination with the accumulated slow-release time and the throttle opening. When the target vehicle enters the EPB takeover state, it is determined whether to exit the EPB takeover state based on the EPB clamping state and the EPB duration.

7. The method according to claim 6, characterized in that, The actual master cylinder pressure is calculated based on the slope value of the slope. If the slope value of the slope is within the first slope range, the actual master cylinder pressure is calculated according to the corresponding ratio based on the master cylinder pressure corresponding to the lowest slope and the master cylinder pressure corresponding to the highest slope within the first slope range. If the slope value of the slope exceeds the first slope range, the master cylinder pressure corresponding to the highest slope within the first slope range will be used as the actual master cylinder pressure.

8. An automatic parking control system, characterized in that, The system is configured to implement the method according to any one of claims 1-7, the system comprising: The first calculation module is used to calculate the slope value of the slope based on the instantaneous slope acceleration of the target vehicle under normal operating conditions; where normal operating conditions refer to the slope acceleration rate not exceeding the limit. The second calculation module is used to calculate the target torque of the target vehicle at idle speed on the slope based on the slope value. The third calculation module is used to calculate the AVH pressure threshold of the target vehicle at the current slope based on the slope value of the slope. The workflow control module is used to control the AVH pressure holding, pressure building, slow release, and EPB takeover workflow based on the target idle torque under idling conditions and the AVH pressure threshold under the current slope.

9. The system according to claim 8, characterized in that, The second calculation module includes: The first torque calculation unit is used to continuously collect multiple engine torque cycles under idling conditions and perform mean filtering to obtain the engine idling torque. The second torque calculation unit is used to calculate the slope idle torque under slope creep conditions based on the engine idle torque; and to convert the slope idle torque into slope resistance. The brake pressure calculation unit is used to calculate the target brake pressure required for parking on the slope based on the slope resistance, master cylinder pressure, and slope value; and to limit the amplitude of the target brake pressure on the slope by combining the slope idle torque. The third torque calculation unit is used to calculate the target idle torque required for starting and releasing AVH based on the slope resistance, transmission type, and slope value of the slope.

10. The system according to claim 8, characterized in that, The third calculation module includes: The first threshold setting unit is used to set a fixed pressure threshold as the AVH pressure threshold under the current slope when the slope value is less than or equal to the second preset slope value. The second threshold setting unit is used to set the AVH pressure threshold at the current slope when the slope value is less than the second preset slope value, based on the slope value and the first pressure threshold calibration table. The first pressure threshold calibration table refers to the mapping table between the slope value and the pressure threshold calibrated in the bench test.

11. An electronic device, characterized in that, The electronic device includes: At least one processor, and a memory communicatively connected to said at least one processor; The memory stores a computer program that can be executed by the at least one processor to enable the at least one processor to perform the steps of the method according to any one of claims 1-7.

12. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that cause a processor to perform the steps of the method according to any one of claims 1-7.

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