A vehicle launch control method, system, and related components

Abstract

The application discloses a vehicle starting control method, system and related components, and relates to the field of automatic driving. The vehicle starting control method comprises the following steps: when a vehicle meets starting control conditions, determining a starting state of the vehicle; the starting state is an uphill state or a downhill state; if the starting state is the uphill state, controlling the motor torque to rise from a current torque value to a target torque value through a driving unit, and then controlling the brake pressure to drop from a parking pressure value to 0 through a brake unit, so as to complete an uphill starting action; if the starting state is the downhill state, controlling the brake pressure to drop from the parking pressure value to a target brake pressure value through the brake unit, so as to complete a downhill starting action. The application can avoid the problems of coasting down a slope, starting too fast and being unable to start for a long time, achieve the purpose of smooth starting of the vehicle on a slope, and guarantee the driving safety of the vehicle.

Description

Technical Field

[0001] This application relates to the field of autonomous driving, and in particular to a vehicle start-up control method, system and related components. Background Technology

[0002] In recent years, with the development of autonomous driving technology, people have placed higher demands on the comfort and safety of autonomous vehicles. Currently, most autonomous vehicles adopt decoupled control of the drive unit and braking unit. When an autonomous vehicle stops on a slope and tries to start, if the drive force and braking force are not well coordinated, problems such as rolling backward, excessively abrupt start, and inability to start for a long time may occur, making it impossible to achieve a smooth start and posing safety hazards.

[0003] Therefore, how to provide a solution to the above-mentioned technical problems is a problem that needs to be solved by those skilled in the art. Summary of the Invention

[0004] The purpose of this application is to provide a vehicle starting control method, system and related components that can avoid problems such as rolling back on slopes, excessively abrupt starts and failure to start for extended periods, thereby achieving smooth vehicle starts on slopes and ensuring vehicle driving safety.

[0005] To address the aforementioned technical problems, this application provides a vehicle start-up control method applied to a vehicle, the vehicle including a drive unit and a braking unit, the vehicle start-up control method comprising:

[0006] When the vehicle meets the start control conditions, the start state of the vehicle is determined; the start state is either uphill or downhill.

[0007] If the starting state is the uphill state, the drive unit controls the motor torque to increase from the current torque value to the target torque value, and then the braking unit controls the braking pressure to decrease from the parking pressure value to 0 to complete the uphill start action;

[0008] If the starting state is the downhill state, the braking pressure is controlled by the braking unit to decrease from the parking pressure value to the target braking pressure value to complete the downhill start action.

[0009] Optionally, before the motor torque is increased from the current torque value to the target torque value by controlling the drive unit, the vehicle start-up control method further includes:

[0010] Obtain the target uphill start acceleration and the overall gear ratio of the vehicle;

[0011] The target torque value is calculated based on the target uphill acceleration and the vehicle's overall gear ratio.

[0012] Optionally, the process of obtaining the target uphill start acceleration of the vehicle includes:

[0013] Determine the current parking scenario of the vehicle; the current parking scenario is either a first parking scenario where there is a target vehicle ahead or a second parking scenario where there is no target vehicle ahead.

[0014] If the current parking scenario is the first parking scenario, the target uphill starting acceleration is determined based on the relative distance and relative speed between the vehicle and the target vehicle;

[0015] If the current parking scenario is the second parking scenario, the target uphill start acceleration is determined according to the set vehicle speed and cruise control.

[0016] Optionally, the process of controlling the braking pressure to decrease from the parking pressure value to 0 via the braking unit includes:

[0017] Obtain the first pressure relief slope;

[0018] The braking unit controls the braking pressure to decrease from the parking pressure value to 0 according to the first pressure relief slope.

[0019] Optionally, the process of obtaining the first pressure relief slope includes:

[0020] The parking pressure value, the target uphill start time, the first time when the motor torque increases from the current torque value to the target torque value, and the first response delay time of the electro-hydraulic braking system are obtained.

[0021] The optimal uphill pressure relief slope is calculated based on the parking pressure value, the target uphill start time, the first time, and the first response delay time.

[0022] The first pressure relief slope is determined based on the optimal uphill pressure relief slope and the maximum pressure relief slope of the electro-hydraulic braking system.

[0023] Optionally, before the braking pressure is controlled by the braking unit to decrease from the parking pressure value to the target braking pressure value, the vehicle start-up control method further includes:

[0024] Obtain the slope value of the road surface where the vehicle is located and the target downhill starting acceleration;

[0025] The target braking pressure value is calculated based on the slope value and the target downhill starting acceleration.

[0026] Optionally, the process of controlling the braking pressure to decrease from the parking pressure value to the target braking pressure value through the braking unit to complete the downhill start action includes:

[0027] When the braking pressure does not reach the target braking pressure value, the braking pressure is controlled to decrease from the parking pressure value to the target braking pressure value through the open-loop control mode of the braking unit.

[0028] Once the braking pressure reaches the target braking pressure value, the braking pressure is adjusted through the closed-loop control mode of the braking unit to complete the downhill start action.

[0029] Optionally, the process of controlling the braking pressure to decrease from the parking pressure value to the target braking pressure value through the open-loop control mode of the braking unit includes:

[0030] Obtain the second pressure relief slope;

[0031] The braking unit controls the braking pressure to decrease from the parking pressure value to the target braking pressure value according to the second pressure relief slope.

[0032] Optionally, the process of obtaining the second pressure relief slope includes:

[0033] Acquire parking pressure value, target braking pressure value, downhill target start time, and first response delay time of the electro-hydraulic braking system;

[0034] The optimal downhill pressure relief slope is calculated based on the parking pressure value, the target braking pressure value, the downhill target start time, and the first response delay time.

[0035] The second pressure relief slope is determined based on the optimal downhill pressure relief slope and the maximum pressure relief slope of the electro-hydraulic braking system.

[0036] To address the aforementioned technical problems, this application also provides a vehicle starting control system applied to a vehicle, the vehicle including a drive unit and a braking unit, the vehicle starting control system including:

[0037] The first determining module is used to determine the starting state of the vehicle when the vehicle meets the starting control conditions; the starting state is either uphill or downhill.

[0038] The first control module is used to control the motor torque to increase from the current torque value to the target torque value through the drive unit when the starting state is the uphill state, and then control the braking pressure to decrease from the parking pressure value to 0 through the braking unit to complete the uphill start action.

[0039] The second control module is used to control the braking pressure to decrease from the parking pressure value to the target braking pressure value through the braking unit when the starting state is the downhill state, so as to complete the downhill start action.

[0040] To address the aforementioned technical problems, this application also provides an electronic device, comprising:

[0041] Memory, used to store computer programs;

[0042] A processor for executing the computer program to implement the steps of the vehicle start-up control method as described in any of the above.

[0043] To address the aforementioned technical problems, this application also provides a vehicle including the electronic equipment described above.

[0044] To address the aforementioned technical problems, this application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the vehicle start-up control method described in any of the above descriptions.

[0045] This application provides a vehicle starting control method. When starting on an uphill slope, the drive unit controls the motor torque to reach the target torque value, and then the braking unit controls the parking pressure to dissipate. When starting on a downhill slope, the braking unit alone controls the braking pressure to decrease from the parking pressure value to the target braking pressure value that allows for a successful downhill start. This achieves precise control of the braking pressure, thus avoiding problems such as rolling back, excessively abrupt starts, and prolonged inability to start. This application achieves smooth vehicle starts on slopes through coordinated control of the drive unit and braking unit, ensuring vehicle safety. This application also provides a vehicle starting control system, electronic equipment, a vehicle, and a computer-readable storage medium, which have the same beneficial effects as the aforementioned vehicle starting control method. Attached Figure Description

[0046] To more clearly illustrate the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 A flowchart illustrating the steps of a vehicle start-up control method provided in this application;

[0048] Figure 2a A schematic diagram of a parking scenario provided in this application;

[0049] Figure 2b A schematic diagram illustrating another parking scenario provided in this application;

[0050] Figure 3 This is a schematic diagram of a vehicle starting control system provided in this application. Detailed Implementation

[0051] The core of this application is to provide a vehicle starting control method, system and related components that can avoid problems such as rolling back on slopes, excessively abrupt starts and failure to start for extended periods, thereby achieving smooth vehicle starts on slopes and ensuring vehicle driving safety.

[0052] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0053] Firstly, please refer to Figure 1 , Figure 1 The present application provides a flowchart of a vehicle start-up control method, which includes:

[0054] S101: When the vehicle meets the starting control conditions, determine the starting state of the vehicle; the starting state is either uphill or downhill.

[0055] It is understood that the vehicle in this application can specifically be a vehicle capable of recognizing the vehicle in front, such as an autonomous vehicle. This application can be applied to the following starting scenarios: the first scenario is starting after parking and following the vehicle in front; the second scenario is starting after parking without a vehicle in front and the driver activates the assisted driving function. Based on this, the starting control conditions in this step include: the vehicle is stationary and receives a starting command, wherein the starting command can be a starting command issued by the autonomous driving controller. When the vehicle is stationary and receives a starting command issued by the autonomous driving controller, the starting state of the vehicle is determined. In this embodiment, the starting state can be an uphill state, a downhill state, or a flat road state, and different starting control schemes are executed for different starting states.

[0056] The starting state of this vehicle can be determined by the slope of the road surface where the vehicle is located. Specifically, the process of determining the starting state of the vehicle includes:

[0057] A slope calculation formula is constructed based on the vehicle's longitudinal acceleration;

[0058] Calculate the slope value using the slope calculation formula; determine the vehicle's starting state based on the slope value.

[0059] Specifically, when the vehicle is stationary and receives a start command from the autonomous driving controller, it reads the acceleration signal from the acceleration sensor, specifically the longitudinal acceleration measured by the sensor. Then, it substitutes the current longitudinal acceleration into a pre-built slope calculation formula to obtain the slope value of the road surface where the vehicle is currently located. The slope calculation formula is as follows: Where i is the slope value, a i Let g be the current longitudinal acceleration, and g be the gravitational acceleration.

[0060] Then, the vehicle's starting state is determined based on the slope value. Specifically, when the slope value is greater than a first preset value i... t1 The vehicle's starting state is determined to be uphill, when the slope value is less than the second preset value i. t2 The vehicle's starting state is determined to be downhill; the first preset value i t1 Greater than the second preset value i t2 When the slope value is in [i t2 i t1 When the vehicle starts, it is determined that the starting state is a flat road state.

[0061] For example, suppose the first preset value i t1 The value is 3%, and the second preset value is i. t2 The slope is set to -3%. If the calculated slope value is greater than 3%, the vehicle is determined to start on an uphill slope. If the calculated slope value is less than -3%, the vehicle is determined to start on a downhill slope. If the calculated slope value is between -3% and 3%, the vehicle is determined to start on a flat road.

[0062] It is understood that a vehicle includes a drive unit and a braking unit. In order to avoid the problem of unsmooth start caused by the decoupling control of the drive unit and the braking unit, this embodiment performs coordinated control of the drive unit and the braking unit. The coordinated control of the drive unit and the braking unit for different start states will be described below.

[0063] S102: If the starting state is uphill, the drive unit controls the motor torque to increase from the current torque value to the target torque value, and then the braking unit controls the braking pressure to decrease from the parking pressure value to 0 to complete the uphill start action.

[0064] S103: If the starting state is downhill, the braking pressure is controlled by the braking unit to decrease from the parking pressure value to the target braking pressure value to complete the downhill start action.

[0065] If the vehicle meets the starting control conditions and the starting state is uphill, the starting action is completed jointly by the drive motor and the electro-hydraulic braking system. First, the target torque value of the drive motor is obtained. The drive unit controls the motor torque to increase from the current torque value. During the increase of motor torque, the parking action is completed by the electro-hydraulic braking system. The braking unit controls the braking pressure to be maintained at the parking pressure value. When the motor torque rises to the target torque value, the braking unit controls the braking pressure to drop to 0, thereby completing the uphill start action. In this embodiment, when starting uphill, the motor torque is first controlled to rise to a certain value before the pressure is released, which can avoid problems such as rolling back on the slope, starting too abruptly, and being unable to start for a long time.

[0066] If the vehicle meets the starting control conditions and the starting state is downhill, the electro-hydraulic braking system completes the starting action. First, the current target braking pressure value is determined. Then, the braking unit controls the braking pressure to decrease from the parking pressure value to the target braking pressure value, thereby releasing pressure and completing the downhill start. This embodiment achieves smooth vehicle start on slopes through coordinated control of the drive unit and braking unit, ensuring vehicle driving safety.

[0067] As can be seen, in this embodiment, when the vehicle starts on an uphill slope, the drive unit controls the motor torque to reach the target torque value, and then the braking unit controls the parking pressure to dissipate. When starting on a downhill slope, the braking unit only controls the braking pressure to drop from the parking pressure value to the target braking pressure value that can complete the downhill start action, thereby achieving precise control of the braking pressure and avoiding problems such as rolling back, starting too abruptly, and being unable to start for a long time.

[0068] Based on the above embodiments:

[0069] As an optional embodiment, before the motor torque is controlled by the drive unit to increase from the current torque value to the target torque value, the vehicle start-up control method further includes:

[0070] Obtain the vehicle's target uphill acceleration and overall gear ratio;

[0071] The target torque value is calculated based on the target uphill starting acceleration and the vehicle's total gear ratio.

[0072] When the vehicle meets the starting control conditions and is in an uphill state, determine the target uphill starting acceleration and overall gear ratio of the vehicle on the current slope, and calculate the target torque value based on the target uphill starting acceleration and overall gear ratio. Specifically, obtain the slope resistance and target uphill starting acceleration, and calculate the starting wheel torque T1 based on the slope resistance and target uphill starting acceleration. First, use the target uphill starting acceleration to calculate the total longitudinal force F applied to the vehicle. X F X= m × a, where m is the vehicle's total mass and a is the target uphill acceleration. Then, based on the obtained aerodynamic forces, rolling resistance, and slope resistance, the acceleration resistance is calculated using the vehicle's longitudinal dynamics equation, where the vehicle's longitudinal dynamics equation is F... X =F w +F f +F i +F j F w For aerodynamics, F f For rolling resistance, F i For the slope resistance, F j To accelerate the resistance, which is the driving force. Using F... j =F X -F w -F f -F i Obtain the acceleration resistance F j Then, the starting wheel end torque T1 is calculated according to the first torque calculation formula, which is T1 = F. j ×R, where R is the wheel radius. Obtain the vehicle's overall gear ratio T. t Then, the target torque value T2 is calculated according to the second torque calculation formula, which is T2 = T1 / T. t In this embodiment, when calculating the motor torque value after completing the uphill start action, a slope signal is added to enable coordinated control of the target motor torque of the drive unit and the target braking pressure of the braking unit, thereby improving control accuracy.

[0073] As an optional embodiment, the process of obtaining the vehicle's target uphill start acceleration includes:

[0074] Determine the vehicle's current parking scenario; the current parking scenario is either the first parking scenario where there is a target vehicle ahead or the second parking scenario where there is no target vehicle ahead.

[0075] If the current parking scenario is the first parking scenario, determine the target uphill starting acceleration based on the relative distance and relative speed between the vehicle and the target vehicle;

[0076] If the current parking scenario is the second parking scenario, determine the target uphill acceleration based on the set vehicle speed and cruise control.

[0077] Understandably, in real-world driving conditions, there are two parking scenarios after a vehicle stops. One is the first parking scenario, where a target vehicle is located in front of the vehicle. The first parking scenario refers to... Figure 2a As shown, the arrow points in the direction of travel forward, CA represents the current vehicle, and CB represents the target vehicle; another scenario is a second parking scenario where there is no target vehicle in front of the current vehicle, as shown in the reference. Figure 2bAs shown, the arrow points in the direction of travel, and CA represents the vehicle itself.

[0078] If the current parking scenario is the first parking scenario, the target uphill start acceleration of the vehicle needs to be determined based on the relative distance and relative speed between the vehicle and the target vehicle (i.e. the vehicle in front) to improve the safety of the vehicle's uphill start process. If there is no target vehicle in front of the vehicle, the target uphill start acceleration is set according to the set speed and cruise control.

[0079] As an optional embodiment, the process of controlling the brake pressure to decrease from the parking pressure value to 0 via the braking unit includes:

[0080] Obtain the first pressure relief slope;

[0081] The braking unit controls the braking pressure to decrease from the parking pressure value to 0 according to the first pressure relief slope.

[0082] During the process of controlling the vehicle to complete an uphill start, when the motor torque reaches the target torque value, the electro-hydraulic braking system activates and begins to perform a pressure relief operation, controlling the braking pressure to decrease from the parking pressure value to 0 through the braking unit. In this embodiment, the first pressure relief slope is obtained, and the determination of the first pressure relief slope takes into account the driver's requirements for comfort and smoothness during the starting process, as well as the actuator capabilities of the vehicle.

[0083] During the depressurization process, this embodiment controls the braking pressure to be depressurized to 0 according to the first depressurization slope. On the one hand, this ensures a smooth start for the vehicle on the slope and avoids the problem of rolling back. On the other hand, while meeting the actuator capabilities of the vehicle, it can also meet the driver's requirements for comfort and smoothness during the starting process, thereby improving the vehicle's driving safety and comfort.

[0084] The first pressure relief slope can be a pre-stored preset value or a dynamic value calculated in real time according to the actual engineering needs. This embodiment does not make specific limitations on the method of obtaining the first pressure relief slope.

[0085] As an optional embodiment, the process of obtaining the first pressure relief slope includes:

[0086] Acquire parking pressure value, target uphill start time, the first time the motor torque increases from the current torque value to the target torque value, and the first response delay time of the electro-hydraulic braking system;

[0087] The optimal uphill pressure relief slope is calculated based on the parking pressure value, the target uphill start time, the first time and the first response delay time.

[0088] The first pressure relief slope is determined based on the optimal uphill pressure relief slope and the maximum pressure relief slope of the electro-hydraulic braking system.

[0089] In this embodiment, the pressure relief operation begins after the motor torque rises to the target torque value. It can be understood that during the process of the motor torque rising, the braking pressure remains at the parking pressure value. Correspondingly, when performing the pressure relief operation, the braking pressure starts to decrease from the parking pressure value. Therefore, when calculating the first pressure relief slope, it is necessary to determine the parking pressure value.

[0090] The process of determining the parking pressure value includes:

[0091] Obtain the preset magnification factor, vehicle mass, and current longitudinal acceleration;

[0092] The parking pressure value is calculated based on the preset amplification factor, the vehicle mass, and the current longitudinal acceleration.

[0093] Specifically, the parking pressure value can be calculated using the parking pressure calculation formula, which is P1=(1+coe)×m×a. i Where P1 is the parking pressure value, coe is the preset amplification factor, m is the vehicle mass, and a i The current longitudinal acceleration caused by the slope (slope acceleration) is 0 when the autonomous vehicle is stationary. The preset amplification factor can be determined based on experience. In this embodiment, the value of coe is not specifically limited.

[0094] In this embodiment, the target uphill start time can be determined based on the driver's starting needs, which include, but are not limited to, requirements for safety, comfort, and smoothness. The process of obtaining the target uphill start time includes:

[0095] Determine the target start time range after the target vehicle leaves;

[0096] Divide the target start time range into multiple sub-start time periods;

[0097] Obtain the evaluation value of each target object for each sub-start time period;

[0098] Calculate the average of all evaluation values ​​for each sub-start time period;

[0099] The target uphill start time is determined based on the average value.

[0100] Specifically, the target objects include, but are not limited to, drivers. Assuming the target start time range is 0s to 10s, the target start time range is divided into segments with intervals of 0.2s. Then, the evaluation value of each target object for each reference start time is obtained. It can be understood that the target object can evaluate each sub-start time period, such as starting 0-0.2s, starting 5-5.2s, or starting 9.8-10s after the preceding vehicle has left, based on its own start needs. The evaluation value is 0 to 10. Assuming there are 20 target objects, then 20 evaluation values ​​can be obtained for each sub-start time period. The average value of the 20 evaluation values ​​is calculated. Then, the average values ​​of each sub-start time period are arranged in descending order. The target uphill start time is selected from the sub-start time period corresponding to the highest average value. Specifically, the median of the sub-start time period corresponding to the highest average value can be determined as the target uphill start time.

[0101] Of course, the target start time range and division interval can be set according to the actual engineering needs, and this application does not make specific limitations here.

[0102] As an optional embodiment, the process of obtaining the first time when the motor torque rises from the current torque value to the target torque value includes: obtaining the first time when the drive unit controls the motor torque to rise from the current torque value to the target torque value at the maximum rise slope of the engine.

[0103] Specifically, the first time can be calculated according to the time calculation formula, where the time calculation formula is t. T =t Tanser +T2 / k TPmax , t T For the first time, T2 is the target torque value, and t Tanser k is the engine response delay time. TPmax This represents the engine's maximum ramp rate.

[0104] The process of calculating the optimal uphill pressure relief slope based on the parking pressure value, target uphill start time, first time, and first response delay time includes:

[0105] The optimal uphill pressure relief slope is calculated based on the first formula for calculating the optimal slope, where k is the first formula for calculating the optimal slope. x =P1 / (t) q -t T -t Panser ), k x The optimal uphill pressure relief slope is given, where P1 is the parking pressure value, and t is the parking pressure value. q For the target uphill start time, t T To be the first, t Panser This is the first response delay time of the vehicle's electro-hydraulic braking system.

[0106] In order to simultaneously meet the driver's starting needs and the vehicle's actuator capabilities, when determining the first pressure relief slope, the minimum value between the optimal uphill pressure relief slope and the maximum pressure relief slope of the electro-hydraulic braking system is selected as the first pressure relief slope. The electro-hydraulic braking system is then controlled to release pressure according to the first pressure relief slope, thereby completing the vehicle's uphill start.

[0107] As an optional embodiment, before the braking pressure is controlled by the braking unit to decrease from the parking pressure value to the target braking pressure value, the vehicle start-up control method further includes:

[0108] Obtain the slope value of the road surface where the vehicle is located and the target downhill starting acceleration;

[0109] The target braking pressure value is calculated based on the gradient and the target downhill starting acceleration.

[0110] The process of obtaining the target downhill start acceleration of the vehicle includes: determining the current parking scenario of the vehicle; the current parking scenario is either a first parking scenario where there is a target vehicle in front of the vehicle or a second parking scenario where there is no target vehicle in front of the vehicle; if the current parking scenario is the first parking scenario, the target downhill start acceleration is determined based on the relative distance and relative speed between the vehicle and the target vehicle; if the current parking scenario is the second parking scenario, the target downhill start acceleration is determined based on the set vehicle speed and cruise control.

[0111] As an optional embodiment, the process of controlling the braking pressure from the parking pressure value to the target braking pressure value through the braking unit to complete the downhill start action includes:

[0112] When the braking pressure does not reach the target braking pressure value, the braking pressure is controlled to decrease from the parking pressure value to the target braking pressure value through the open-loop control mode of the braking unit.

[0113] Once the braking pressure reaches the target braking pressure value, the braking pressure is adjusted through the closed-loop control mode of the braking unit to complete the downhill start action.

[0114] In this embodiment, the parking pressure value is the current braking pressure value when the vehicle meets the start control conditions. The downhill start control in this embodiment includes open-loop control and closed-loop control. When the braking pressure does not reach the target braking pressure value, the open-loop control loop is entered first to release the pressure. When the braking pressure reaches the target braking pressure value, the closed-loop control loop is entered to complete the downhill start action.

[0115] It is understood that the open-loop control and closed-loop control in this embodiment can be performed simultaneously. When the braking pressure has not reached the target braking pressure value, the electro-hydraulic braking system uses the output of the open-loop control as the control basis, and the output of the closed-loop control is not used. After the braking pressure reaches the target braking pressure value, the electro-hydraulic braking system uses the output of the closed-loop control as the control basis, so that the vehicle enters closed-loop control and completes the start-up, thereby improving control efficiency and accuracy.

[0116] As an optional embodiment, the process of controlling the braking pressure to decrease from the parking pressure value to the target braking pressure value through the open-loop control mode of the braking unit includes:

[0117] Obtain the second pressure relief slope;

[0118] The braking unit controls the braking pressure to decrease from the parking pressure value to the target braking pressure value according to the second pressure relief slope.

[0119] As an optional embodiment, the process of obtaining the second pressure relief slope includes:

[0120] Acquire parking pressure value, target braking pressure value, downhill target start time, and first response delay time of the electro-hydraulic braking system;

[0121] The optimal downhill pressure relief slope is calculated based on the parking pressure value, target braking pressure value, downhill target start time, and first response delay time.

[0122] The second pressure relief slope is determined based on the optimal downhill pressure relief slope and the maximum pressure relief slope of the electro-hydraulic braking system.

[0123] In the open-loop control loop, the target braking pressure value is the downhill start braking pressure value. The target downhill start time is determined according to the scheme for determining the target start time in the above embodiment. The optimal downhill pressure relief slope is calculated based on the parking pressure value, the target braking pressure value, the downhill target start time, and the first response delay time of the electro-hydraulic braking system. Specifically, the optimal downhill pressure relief slope can be calculated according to the second optimal slope calculation formula, which is k2=(P z -P2) / (t q -t Panser ), where k2 is the optimal downhill pressure relief slope, P z P1 is the actual parking pressure value, P2 is the target braking pressure value, and t is the actual parking pressure value. q For the target downhill start time, t Panser This refers to the response delay time of the electro-hydraulic braking system, i.e., the first response delay time.

[0124] Similarly, to simultaneously meet the driver's starting needs and the vehicle's actuator capabilities, after calculating the optimal downhill pressure relief slope, the minimum value between the optimal downhill pressure relief slope and the maximum pressure relief slope of the electro-hydraulic braking system is selected as the second pressure relief slope to control the parking pressure P. z The vehicle is brought down to the target braking pressure value with the second pressure relief slope, and then switches to closed-loop control to complete the downhill start.

[0125] As an optional embodiment, the operating environment for the above-mentioned start-up control action is that the intelligent assistance function is activated and the vehicle is in EPB (electronic parking brake) pressure holding state.

[0126] In summary, this application incorporates a slope signal to coordinate and control the torque of the drive unit and the braking force of the braking unit in order to achieve a smooth start for the vehicle on a slope.

[0127] Secondly, please refer to Figure 3 , Figure 3 This application provides a schematic diagram of a vehicle starting control system, which includes:

[0128] The first determining module 1 is used to determine the starting state of the vehicle when the vehicle meets the starting control conditions; the starting state is either uphill or downhill.

[0129] The first control module 2 is used to control the motor torque to increase from the current torque value to the target torque value through the drive unit when the starting state is uphill, and then control the braking pressure to decrease from the parking pressure value to 0 through the braking unit to complete the uphill start action.

[0130] The second control module 3 is used to control the braking pressure from the parking pressure value to the target braking pressure value through the braking unit when the starting state is downhill, so as to complete the downhill starting action.

[0131] As can be seen, in this embodiment, when the vehicle starts uphill, the drive unit controls the motor torque to reach the target torque value, and then the braking unit controls the parking pressure to dissipate. When starting downhill, the braking unit only controls the braking pressure to drop from the parking pressure value to the target braking pressure value that can complete the downhill start action, thereby achieving precise control of the braking pressure and avoiding problems such as rolling back, excessively abrupt starts, and failure to start for a long time. This application achieves the purpose of smooth vehicle start on slopes by coordinating the control of the drive unit and the braking unit, thus ensuring vehicle driving safety.

[0132] As an optional embodiment, the vehicle start control system further includes:

[0133] The first preprocessing module is used to obtain the vehicle's target uphill starting acceleration and the vehicle's total transmission ratio.

[0134] The first calculation module is used to calculate the target torque value based on the target uphill starting acceleration and the vehicle's total transmission ratio.

[0135] As an optional embodiment, the process of obtaining the vehicle's target uphill start acceleration includes:

[0136] Determine the vehicle's current parking scenario; the current parking scenario is either the first parking scenario where there is a target vehicle ahead or the second parking scenario where there is no target vehicle ahead.

[0137] If the current parking scenario is the first parking scenario, determine the target uphill starting acceleration based on the relative distance and relative speed between the vehicle and the target vehicle;

[0138] If the current parking scenario is the second parking scenario, determine the target uphill acceleration based on the set vehicle speed and cruise control.

[0139] As an optional embodiment, the process of controlling the brake pressure to decrease from the parking pressure value to 0 via the braking unit includes:

[0140] Obtain the first pressure relief slope;

[0141] The braking unit controls the braking pressure to decrease from the parking pressure value to 0 according to the first pressure relief slope.

[0142] As an optional embodiment, the process of obtaining the first pressure relief slope includes:

[0143] Acquire parking pressure value, target uphill start time, the first time when motor torque increases from the current torque value to the target torque value, and the first response delay time of the braking unit;

[0144] The optimal uphill pressure relief slope is calculated based on the parking pressure value, the target uphill start time, the first time and the first response delay time.

[0145] The first pressure relief slope is determined based on the optimal uphill pressure relief slope and the maximum pressure relief slope of the braking unit.

[0146] As an optional embodiment, the vehicle start control system further includes:

[0147] The first acquisition module is used to acquire the slope value of the road surface where the vehicle is located and the target downhill starting acceleration;

[0148] The second calculation module is used to calculate the target braking pressure value based on the gradient value and the target downhill starting acceleration.

[0149] As an optional embodiment, the process of controlling the braking pressure from the parking pressure value to the target braking pressure value through the braking unit to complete the downhill start action includes:

[0150] When the braking pressure does not reach the target braking pressure value, the braking pressure is controlled to decrease from the parking pressure value to the target braking pressure value through the open-loop control mode of the braking unit.

[0151] Once the braking pressure reaches the target braking pressure value, the braking pressure is adjusted through the closed-loop control mode of the braking unit to complete the downhill start action.

[0152] As an optional embodiment, the process of controlling the braking pressure to decrease from the parking pressure value to the target braking pressure value through the open-loop control mode of the braking unit includes:

[0153] Obtain the second pressure relief slope;

[0154] The braking unit controls the braking pressure to decrease from the parking pressure value to the target braking pressure value according to the second pressure relief slope.

[0155] As an optional embodiment, the process of obtaining the second pressure relief slope includes:

[0156] Acquire parking pressure value, target braking pressure value, downhill target start time, and first response delay time of the braking unit;

[0157] The optimal downhill pressure relief slope is calculated based on the parking pressure value, target braking pressure value, downhill target start time, and first response delay time.

[0158] The second pressure relief slope is determined based on the optimal downhill pressure relief slope and the maximum pressure relief slope of the braking unit.

[0159] Thirdly, this application also provides an electronic device, including:

[0160] Memory, used to store computer programs;

[0161] A processor is used to execute a computer program to implement the steps of the vehicle start-up control method as described in any of the embodiments above.

[0162] For a description of the electronic device provided in this application, please refer to the above embodiments; further details will not be repeated here.

[0163] The electronic device provided in this application has the same beneficial effects as the vehicle start-up control method described above.

[0164] Fourthly, this application also provides a vehicle including electronic equipment as described in the embodiments above.

[0165] For a description of the vehicle provided in this application, please refer to the above embodiments; further details will not be repeated here.

[0166] The vehicle provided in this application has the same beneficial effects as the aforementioned vehicle start-up control method.

[0167] Fifthly, this application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the vehicle start-up control method as described in any of the embodiments above.

[0168] For a description of the computer-readable storage medium provided in this application, please refer to the above embodiments; further details will not be repeated here.

[0169] The computer-readable storage medium provided in this application has the same beneficial effects as the vehicle start-up control method described above.

[0170] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0171] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A vehicle starting control method, characterized in that, Applied to a vehicle, the vehicle including a drive unit and a braking unit, the vehicle start-up control method includes: When the vehicle meets the start control conditions, the start state of the vehicle is determined; the start state is either uphill or downhill. If the starting state is the uphill state, the drive unit controls the motor torque to increase from the current torque value to the target torque value, and then the braking unit controls the braking pressure to decrease from the parking pressure value to 0 to complete the uphill start action; If the starting state is the downhill state, the braking pressure is controlled by the braking unit to decrease from the parking pressure value to the target braking pressure value to complete the downhill start action; Before the braking pressure is controlled by the braking unit to decrease from the parking pressure value to the target braking pressure value, the vehicle start-up control method further includes: Obtain the slope value of the road surface where the vehicle is located and the target downhill starting acceleration; The target braking pressure value is calculated based on the slope value and the target downhill starting acceleration. The process of controlling the braking pressure by the braking unit to decrease from the parking pressure value to the target braking pressure value to complete the downhill start action includes: When the braking pressure does not reach the target braking pressure value, the braking pressure is controlled to decrease from the parking pressure value to the target braking pressure value through the open-loop control mode of the braking unit. Once the braking pressure reaches the target braking pressure value, the braking pressure is adjusted through the closed-loop control mode of the braking unit to complete the downhill start action. The process of controlling the braking pressure to decrease from the parking pressure value to the target braking pressure value through the open-loop control mode of the braking unit includes: Obtain the second pressure relief slope; The braking unit controls the braking pressure to decrease from the parking pressure value to the target braking pressure value according to the second pressure relief slope. The process of obtaining the second pressure relief slope includes: Acquire parking pressure value, target braking pressure value, downhill target start time, and first response delay time of the electro-hydraulic braking system; The optimal downhill pressure relief slope is calculated based on the parking pressure value, the target braking pressure value, the downhill target start time, and the first response delay time. The second pressure relief slope is determined based on the optimal downhill pressure relief slope and the maximum pressure relief slope of the electro-hydraulic braking system.

2. The vehicle starting control method according to claim 1, characterized in that, Before the motor torque is increased from the current torque value to the target torque value by controlling the drive unit, the vehicle start-up control method further includes: Obtain the target uphill start acceleration and the overall gear ratio of the vehicle; The target torque value is calculated based on the target uphill acceleration and the vehicle's overall gear ratio.

3. The vehicle starting control method according to claim 2, characterized in that, The process of obtaining the target uphill start acceleration of the vehicle includes: Determine the current parking scenario of the vehicle; the current parking scenario is either a first parking scenario where there is a target vehicle ahead or a second parking scenario where there is no target vehicle ahead. If the current parking scenario is the first parking scenario, the target uphill starting acceleration is determined based on the relative distance and relative speed between the vehicle and the target vehicle; If the current parking scenario is the second parking scenario, the target uphill start acceleration is determined according to the set vehicle speed and cruise control.

4. The vehicle starting control method according to claim 1, characterized in that, The process of controlling the braking pressure to decrease from the parking pressure value to 0 via the braking unit includes: Obtain the first pressure relief slope; The braking unit controls the braking pressure to decrease from the parking pressure value to 0 according to the first pressure relief slope.

5. The vehicle starting control method according to claim 4, characterized in that, The process of obtaining the first pressure relief slope includes: The parking pressure value, the target uphill start time, the first time when the motor torque increases from the current torque value to the target torque value, and the first response delay time of the electro-hydraulic braking system are obtained. The optimal uphill pressure relief slope is calculated based on the parking pressure value, the target uphill start time, the first time, and the first response delay time. The first pressure relief slope is determined based on the optimal uphill pressure relief slope and the maximum pressure relief slope of the electro-hydraulic braking system.

6. A vehicle starting control system, characterized in that, Applied to a vehicle, the vehicle including a drive unit and a braking unit, the vehicle start control system includes: The first determining module is used to determine the starting state of the vehicle when the vehicle meets the starting control conditions; the starting state is either uphill or downhill. The first control module is used to control the motor torque to increase from the current torque value to the target torque value through the drive unit when the starting state is the uphill state, and then control the braking pressure to decrease from the parking pressure value to 0 through the braking unit to complete the uphill start action. The second control module is used to control the braking pressure to decrease from the parking pressure value to the target braking pressure value through the braking unit when the starting state is the downhill state, so as to complete the downhill start action; Also includes: The first acquisition module is used to acquire the slope value of the road surface where the vehicle is located and the target downhill starting acceleration; The second calculation module is used to calculate the target braking pressure value based on the slope value and the target downhill starting acceleration. The process of controlling the braking pressure by the braking unit to decrease from the parking pressure value to the target braking pressure value to complete the downhill start action includes: When the braking pressure does not reach the target braking pressure value, the braking pressure is controlled to decrease from the parking pressure value to the target braking pressure value through the open-loop control mode of the braking unit. Once the braking pressure reaches the target braking pressure value, the braking pressure is adjusted through the closed-loop control mode of the braking unit to complete the downhill start action. The process of controlling the braking pressure to decrease from the parking pressure value to the target braking pressure value through the open-loop control mode of the braking unit includes: Obtain the second pressure relief slope; The braking unit controls the braking pressure to decrease from the parking pressure value to the target braking pressure value according to the second pressure relief slope. The process of obtaining the second pressure relief slope includes: Acquire parking pressure value, target braking pressure value, downhill target start time, and first response delay time of the electro-hydraulic braking system; The optimal downhill pressure relief slope is calculated based on the parking pressure value, the target braking pressure value, the downhill target start time, and the first response delay time. The second pressure relief slope is determined based on the optimal downhill pressure relief slope and the maximum pressure relief slope of the electro-hydraulic braking system.

7. An electronic device, characterized in that, include: Memory, used to store computer programs; A processor, configured to implement the steps of the vehicle start-up control method as described in any one of claims 1-5 when executing the computer program.

8. A vehicle, characterized in that, Including the electronic device as described in claim 7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the vehicle start-up control method as described in any one of claims 1-5.

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