An automatic parking dynamic shifting method, system, device and storage medium

Abstract

This application relates to an automatic parking dynamic gear shifting method, system, device, and storage medium. The automatic parking dynamic gear shifting method is characterized by comprising: responding to an automatic parking command, shifting gears while the vehicle is traveling in a first direction to a gear corresponding to a second direction opposite to the first direction, wherein the first direction is a forward direction and the second direction is a reverse direction; a drive motor providing torque to the vehicle in the second direction to drive the vehicle speed to gradually decrease from the forward speed in the first direction to 0, and when the forward speed in the first direction is 0, the torque in the second direction is not 0. Therefore, this solves the technical problem in related technologies where automatic parking requires first stopping the vehicle and then shifting gears to start, resulting in low shifting efficiency and a poor user driving experience.

Description

Technical Field

[0001] This application relates to the field of vehicle control, and in particular to an automatic parking dynamic shifting method, system, device, and storage medium. Background Technology

[0002] In traditional automatic parking, when the vehicle is in D gear moving forward, to switch to R gear to continue parking, the vehicle will first brake to a stop, then shift gears, and then start moving again to reverse the direction of the vehicle.

[0003] During this process, the parking state machine needs to transition from cruise control to braking, stopping, handshaking, and starting. This means that the hydraulic brake actuator needs to go through pressure building, pressure holding, pressure release, and motor response times, resulting in a pause of more than 3 seconds during the gear shifting process. This leads to low efficiency and a poor driving experience for the user. Summary of the Invention

[0004] This application provides an automatic parking dynamic gear shifting method, system, device, and storage medium to solve the technical problem in the related art that when a vehicle is automatically parked, it needs to stop first and then shift gears to start, which results in low shifting efficiency and a poor driving experience for the user.

[0005] Firstly, an automatic parking dynamic gear shifting method is provided, which includes: In response to an automatic parking command, while the vehicle is traveling in a first direction, the gear is shifted to the gear corresponding to the second direction opposite to the first direction, wherein the first direction is the forward direction and the second direction is the reverse direction; The drive motor provides torque to the vehicle in the second direction to drive the vehicle speed to gradually decrease from the positive speed in the first direction to 0, and when the positive speed of the vehicle in the first direction is 0, the torque in the second direction is not 0.

[0006] In conjunction with the first aspect, in one embodiment, before shifting gears to a gear corresponding to a second direction opposite to the first direction while the vehicle is traveling in a first direction in response to an automatic parking command, the method further includes: Detect whether the vehicle has a slope value, and obtain the vehicle speed in the first direction and the parking point in the first direction; If a vehicle slope exists, and the vehicle speed is lower than the preset speed value but greater than zero, and the distance the vehicle travels to the parking point in the first direction is less than the first distance, then an automatic parking command will be executed. If there is no vehicle slope value, the vehicle enters a static shift state.

[0007] In conjunction with the first aspect, the step of responding to the automatic parking command if a vehicle slope exists, the vehicle speed is lower than a preset speed value but greater than zero, and the distance the vehicle travels to the parking point in the first direction is less than a first distance, further includes: If a vehicle slope exists and the vehicle speed is higher than the preset speed value, and / or the distance the vehicle travels to the parking point in the first direction is greater than a first distance, then the vehicle will maintain its driving state in the first direction until the vehicle speed is lower than the preset speed value and greater than zero, and the distance the vehicle travels to the parking point in the first direction is less than the first distance, and then the automatic parking command will be responded to.

[0008] In conjunction with the first aspect, the detection of whether the vehicle has a slope value includes: The vehicle slope value is detected within a preset period, and the instantaneous slope value of the vehicle within each period is obtained. If, within a preset period, all instantaneous slope values ​​are less than or equal to the slope threshold, or all instantaneous slope values ​​are greater than the slope threshold, then the vehicle has a vehicle slope value. If, within a preset period, the number of times each instantaneous slope value exceeds the slope threshold and the number of times it falls below the slope threshold both exceed the set number, then the vehicle will not have a vehicle slope value.

[0009] In conjunction with the first aspect, the step of responding to an automatic parking command and shifting gears to a gear corresponding to a second direction opposite to the first direction while the vehicle is traveling in the first direction further includes: In response to an automatic parking command, while the vehicle is traveling in a first direction, the gear is shifted to the gear corresponding to the second direction opposite to the first direction, and the vehicle's driving state is corrected in the opposite direction, wherein the vehicle's driving state includes at least the vehicle speed.

[0010] In conjunction with the first aspect, in one embodiment, the drive motor provides the vehicle with torque for travel in the second direction, comprising: Obtain the vehicle's ramp value; Based on the vehicle's gradient, the torque provided by the drive motor for the vehicle to travel in the second direction is calculated.

[0011] In conjunction with the first aspect, in one implementation, obtaining the vehicle ramp value includes: If all instantaneous slope values ​​are less than or equal to the slope threshold within the preset period, then the vehicle slope value is 0. If all instantaneous ramp values ​​are greater than the ramp threshold within the preset period, then the instantaneous ramp value corresponding to the last period will be used as the vehicle ramp value.

[0012] In conjunction with the first aspect, in one implementation, if the vehicle's gradient value is 0, the reverse correction of the vehicle's driving state includes: The vehicle speed data is processed in reverse so that the vehicle speed data changes from a positive speed in the first direction to a negative speed in the first direction.

[0013] In conjunction with the first aspect, in one embodiment, the drive motor provides the vehicle with torque for travel in the second direction, comprising: When responding to an automatic parking command, the torque is calculated based on the vehicle's travel distance to the parking point in the first direction and the vehicle's speed.

[0014] In conjunction with the first aspect, in one implementation, if the instantaneous ramp value corresponding to the last cycle is used as the vehicle ramp value, then the vehicle driving state also includes the vehicle ramp value, and the reverse correction of the vehicle driving state includes: The vehicle speed and vehicle gradient values ​​are reversed so that the vehicle speed data changes from a positive speed in the first direction to a negative speed in the first direction, and the vehicle gradient value data changes from a positive vehicle gradient value in the first direction to a negative vehicle gradient value in the first direction.

[0015] In conjunction with the first aspect, in one embodiment, obtaining the slope compensation force of the vehicle along a first direction at the current slope value includes: Calculate the slope compensation force in the first direction based on the vehicle's weight and the absolute value of the current slope value. The vehicle's current slope includes both uphill and downhill states: If the vehicle is currently uphill, the driving force will provide slope compensation force and slow down the vehicle. If the vehicle is on a downhill slope, the braking force will provide slope compensation and slow the vehicle down.

[0016] In conjunction with the first aspect, in one embodiment, the drive motor provides the vehicle with torque for travel in the second direction, comprising: A fifth-order polynomial model is established based on vehicle travel time and real-time motor torque. Obtain the slope compensation force, rate of change, and acceleration of the vehicle along the first direction at the current vehicle slope value; The second slope compensation force in the second direction at the moment of gear shift is taken as the target force, and the target rate of change and target acceleration of the vehicle when it is under the target force are obtained; Using the target force, target speed, target acceleration, and the vehicle's slope compensation force, vehicle speed, and vehicle acceleration in the first direction as boundary conditions in the fifth-order polynomial model, the coefficients of each term in the fifth-order polynomial model are calculated to obtain the fifth-order polynomial calculation formula. Based on the fifth-order polynomial calculation formula, the torque variation curve of the drive motor for the vehicle to travel in the second direction is obtained.

[0017] In conjunction with the first aspect, in one embodiment, obtaining the slope compensation force of the vehicle along a first direction at the current slope value includes: Calculate the slope compensation force in the first direction based on the vehicle's weight and the absolute value of the current slope.

[0018] Secondly, an automatic parking dynamic shifting system is provided, comprising: The first module is used to send parking signals; The second module is used to respond to a parking signal and shift gears to the corresponding gear in the second direction opposite to the first direction while the vehicle is traveling in the first direction. The third module is used to drive the motor to provide torque for the vehicle to travel in the second direction, so as to drive the vehicle speed to gradually decrease from the positive speed in the first direction to 0, and when the positive speed of the vehicle in the first direction is 0, the torque in the second direction is not 0.

[0019] Thirdly, an automatic parking dynamic shifting device is provided, the automatic parking dynamic shifting device including a processor, a memory, and an automatic parking dynamic shifting program stored in the memory and executable by the processor, wherein when the automatic parking dynamic shifting program is executed by the processor, it implements the steps of the automatic parking dynamic shifting method.

[0020] Fourthly, a computer-readable storage medium is provided, on which an automatic parking dynamic shifting program is stored, wherein when the automatic parking dynamic shifting program is executed by a processor, the steps of the automatic parking dynamic shifting method as described above are implemented.

[0021] The beneficial effects of the technical solution provided in this application include: During automatic parking, when the vehicle responds to the automatic parking command, it shifts gears to the corresponding gear in the second direction opposite to the first direction while traveling in the first direction, completing the gear shift. Although the gear is in the second direction, the vehicle is still actually decelerating in the first direction. Simultaneously with the gear shift, the drive motor provides torque to the vehicle in the second direction, causing this torque to decelerate the vehicle speed in the first direction and gradually change the vehicle speed from positive in the first direction to positive in the second direction. That is, when the torque in the second direction causes the vehicle speed to decrease to 0 in the first direction, the vehicle still has torque in the second direction. Therefore, at this point, the vehicle speed is 0, but the vehicle acceleration is not 0. The vehicle does not stop but immediately moves in the second direction, completing the reversal of the vehicle's direction, thus aligning the vehicle's actual direction of travel with the gear position, completing the dynamic gear shift.

[0022] This application provides an automatic parking dynamic gear shifting method, system, device, and storage medium. Because the vehicle does not stop during gear shifting in the automatic parking process and always maintains the vehicle's running state, the overall parking process is smoother. Therefore, it solves the technical problem in related technologies where the vehicle needs to stop first and then shift gears to start when automatically parking, resulting in low gear shifting efficiency and a poor user driving experience. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0024] Figure 1 An automatic parking dynamic gear shifting method is provided in the embodiments of this application; Figure 2 This is a flowchart illustrating the dynamic gear shifting and parking process of a new energy vehicle, as provided in this application embodiment. Detailed Implementation

[0025] 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.

[0026] This application provides an automatic parking dynamic gear shifting method, system, device, and storage medium, which can solve the technical problem in the related art that when a vehicle is automatically parked, it needs to stop first and then shift gears to start, resulting in low shifting efficiency and a poor driving experience for the user.

[0027] Reference Figure 1 Typically, when new energy vehicles perform automatic parking, the vehicle initially decelerates forward in D gear due to the braking force provided by the hydraulic brake actuator (hereinafter referred to as braking force influence). To switch to R gear to continue parking, the vehicle will first be brought to a stop in the forward direction due to the braking force, then shift from D gear to R gear, and finally start moving in the opposite direction. During this process, the parking state machine needs to go from cruise control to stopping, standing still, handshaking, and starting. That is, the hydraulic brake actuator needs to go through pressure building, pressure holding, pressure release, and motor response time, resulting in a pause of more than 3 seconds in the shifting process, which is inefficient.

[0028] In view of the problems existing in the automatic parking of new energy vehicles mentioned above, this application provides a dynamic gear shifting method for automatic parking, which includes the following steps: S1: In response to the automatic parking command, while the vehicle is traveling in the first direction, shift to the gear corresponding to the second direction opposite to the first direction; When the vehicle responds to the automatic parking command, the vehicle's parking state machine directly enters the dynamic shifting state from the cruise state. In the dynamic shifting state, the vehicle maintains the state of traveling in the first direction and shifts to the corresponding gear in the second direction opposite to the first direction. That is, when the vehicle's parking state machine is in the dynamic shifting state, the vehicle is allowed to maintain the gear in the second direction but still travel in the first direction.

[0029] For example, in this embodiment, the first direction is the forward direction, i.e., D gear; the second direction is the reverse direction, i.e., R gear. Before responding to the automatic parking command, the vehicle's parking state machine is in cruise mode, at which time the vehicle is in D gear and decelerating forward in the first direction. When the vehicle responds to the automatic parking command, the vehicle's parking state machine switches from cruise mode to dynamic shifting mode. At this time, the vehicle shifts to R gear, but still maintains D gear and decelerates forward. That is, when responding to the automatic parking command, the vehicle completes the gear shift and enters dynamic shifting mode, but at this time, the vehicle has not completed the reversal of the driving direction.

[0030] When responding to an automatic parking command and shifting the vehicle into reverse (R), although the gear is already in reverse, there is still a distance between the vehicle and the parking spot. Therefore, the vehicle continues to travel in the first direction. In other words, when responding to an automatic parking command, the vehicle is in a dynamic shifting state machine, allowing it to be in reverse but still maintaining forward motion.

[0031] During vehicle movement, the automatic parking command signal is issued by the vehicle's upper-level system after detecting the actual environment around the vehicle. There may be situations where the vehicle's parking state machine does not meet the dynamic shifting conditions. Therefore, before responding to the automatic parking command and shifting the vehicle to reverse gear, it is necessary to determine whether the vehicle's parking state machine currently meets the dynamic shifting conditions for directly transitioning from cruise control to dynamic shifting mode. This includes the following steps: S101: Detect whether the vehicle has a slope value, and obtain the vehicle speed in the first direction and the parking point in the first direction. Specifically, detecting the vehicle's gradient value during operation is an intelligent process that relies on real-time fusion of data from multiple sensors. At its core lies the onboard inertial measurement unit (IMU), which continuously measures the vehicle's acceleration and rotational angular velocity in three directions. When a vehicle is traveling on a slope, gravitational acceleration produces specific components in the vehicle's forward / backward and left / right directions. The IMU senses these changes in gravitational components to provide raw data for calculating the gradient angle (vehicle pitch angle) and roll angle (vehicle roll angle).

[0032] However, the vehicle's own acceleration, deceleration, or turning during operation generates additional inertial forces, severely interfering with IMU readings. To accurately extract the gravity signal representing the true slope from dynamic noise, the vehicle's vehicle control unit (VCU) runs a complex filtering and fusion algorithm, such as Kalman filtering. This algorithm compares and cross-validates the raw IMU data with information from the wheel speed sensors (four wheel speeds), the real-time drive / braking torque feedback from the motor controller, and the steering angle sensor.

[0033] For example, by comparing the torque output by the drive motor with the actual acceleration of the vehicle, the system can deduce the road resistance, thus aiding in the judgment of the gradient; by analyzing the wheel speed changes of the non-drive wheels, it can also provide evidence for the gradient estimation. Through this continuous fusion and correction of multi-source information, the system can calculate accurate and reliable gradient values ​​in real time under various dynamic driving conditions of the vehicle.

[0034] Therefore, during vehicle operation, the instantaneous slope value is the value obtained by integrating and calculating the multi-sensor data of the vehicle within one cycle. However, the instantaneous slope value within one cycle can only represent the slope value during the vehicle's operation within that cycle. Since the detection cycle is relatively short, in order to eliminate the instantaneous influence during vehicle operation, it is necessary to detect the vehicle's slope value within multiple preset cycles to determine the current vehicle slope value.

[0035] S101(a): If there is a vehicle slope value, and the vehicle speed is lower than the preset speed value but greater than zero, and the distance the vehicle travels to the parking point in the first direction is less than the first distance, then respond to the automatic parking command. Because vehicles encounter various road conditions during operation, including flat roads, sloping roads, and roads with varying inclines and declines, the forces exerted on a vehicle when decelerating in D gear differ depending on the road conditions.

[0036] When a vehicle is traveling on both flat and sloping roads, there is a stable vehicle gradient. However, when a vehicle decelerates in Drive (D) mode, the forces acting on it differ between flat and sloping roads. For example, on a flat road, the vehicle is only affected by the braking force provided by the vehicle's braking system to decelerate in the first direction; while on a sloping road, the vehicle's own weight must also be considered when decelerating.

[0037] For example, when going uphill on a slope, the vehicle's direction of travel is opposite to the direction of the gravitational component at the current slope. Since the gravitational component causes the vehicle to decelerate when going uphill, to prevent excessive deceleration, the electric motor needs to provide forward torque to compensate. Therefore, when going uphill, the positive torque provided by the motor in the first direction provides slope compensation force and decelerates the vehicle. It should be understood that the slope compensation force should be less than the gravitational component to ensure that the change in vehicle speed is minimized. Conversely, when going downhill on a slope, the vehicle's direction of travel is the same as the direction of the gravitational component at the current slope. Since the gravitational component causes the vehicle to accelerate when going uphill, to decelerate the vehicle when going downhill, the vehicle's braking system needs to provide braking force in the second direction to counteract the slope compensation force and decelerate the vehicle. It should be understood that the slope compensation force should be less than the gravitational component to ensure that the change in vehicle speed is minimized.

[0038] Before responding to the automatic parking command, the vehicle travels in the first direction, i.e., the forward direction. At this time, the vehicle is in D gear and gradually decelerates. When the vehicle decelerates until its speed in the first direction is zero, it has a parking point in the first direction.

[0039] As the vehicle travels in the first direction, it gradually moves towards the parking spot. The real-time distance between the vehicle's current position and the parking spot in the first direction is the distance the vehicle travels to the parking spot in the first direction.

[0040] To avoid the vehicle system misinterpreting it as a rollaway and triggering other logic, the first distance during vehicle operation is the safe distance that the vehicle can maintain even when in reverse gear. In the early design phase, this first distance needs to be preset based on the vehicle's road conditions and its own performance.

[0041] Similarly, if the current vehicle speed is too high, directly shifting gears will also cause excessive vehicle pitch, resulting in a poor driving experience for the user. Therefore, based on the vehicle's road conditions and its own performance, it is necessary to preset the vehicle's speed. When the vehicle is moving forward, that is, traveling in the first direction, and the vehicle speed is lower than the preset speed but greater than zero, the vehicle will continue to move forward while maintaining the reverse gear. This can limit the vehicle pitch within a smooth range and provide a better experience for the user.

[0042] Typically, new energy vehicles are equipped with active wheel speed sensors. These sensors can not only calculate the precise wheel speed, but also determine the rotation direction of the wheels by the phase difference between the two-channel signals, thereby determining the vehicle's direction of travel and current speed.

[0043] In one embodiment of this application, when responding to an automatic parking command and shifting the vehicle to reverse gear, although the vehicle is already in reverse (R), there is still a distance between the vehicle and the parking spot. Therefore, the vehicle continues to travel in the first direction. That is, when responding to the automatic parking command, the vehicle is in a dynamic shift state machine, allowing the vehicle to be in reverse gear, but still maintaining a forward driving state. During vehicle movement, the automatic parking command signal is issued by the vehicle's upper-level system after detecting the actual environment around the vehicle. There may be situations where the distance from the vehicle to the parking spot in the first direction is greater than a first distance, and / or the vehicle speed is higher than a preset speed value. To avoid the vehicle system mistakenly identifying this as the vehicle rolling backward and triggering other logic, the vehicle continues to travel in the first direction until the vehicle speed is lower than the preset speed value but greater than zero, and the distance from the vehicle to the parking spot in the first direction is less than the first distance. At this point, in response to the automatic parking command, the vehicle shifts to reverse gear, completing the gear shift.

[0044] S101(b): If there is no vehicle slope value, the vehicle enters a static shift state; When dealing with road surfaces that change from uphill to downhill, the vehicle's driving environment constantly changes between flat and sloping surfaces, resulting in a continuous change in the vehicle's gradient value. Therefore, when dealing with road surfaces that change from uphill to downhill, the vehicle does not have a gradient value.

[0045] For example, when driving from a flat road onto a slope, the vehicle's speed changes from being unaffected by its own gravity to being affected by it. The additional resistance provided by its own gravity will directly cause the vehicle's speed to decelerate to 0 earlier, causing the vehicle to stop before reaching the parking point in the first direction. Conversely, when driving from a slope onto a flat road, the vehicle changes from being affected by its own gravity to being unaffected by it. As the vehicle moves in the first direction, its own gravity provides additional forward driving force because it is in the same direction as the direction of travel. Under the influence of inertia, the vehicle's speed may exceed the preset value, thus requiring the braking system to intervene and bring the vehicle to a stop.

[0046] Therefore, when responding to an automatic parking command, the vehicle only shifts gears to the corresponding gear in the second direction (opposite to the first direction) when the vehicle is traveling in the first direction on a flat or sloping road surface. If the vehicle is on a road surface with varying inclines or declines, the vehicle's parking state machine transitions from cruise control to a stopped state, performing a static gear shift.

[0047] S102: Detecting whether the vehicle has a slope value includes the following steps: The vehicle slope value is detected within a preset period, and the instantaneous slope value of the vehicle within each period is obtained. If, within a preset period, all instantaneous slope values ​​are less than or equal to the slope threshold, or all instantaneous slope values ​​are greater than the slope threshold, then the vehicle has a vehicle slope value. If, within a preset period, the number of times each instantaneous slope value exceeds the slope threshold and the number of times it falls below the slope threshold both exceed the set number, then the vehicle will not have a vehicle slope value.

[0048] Specifically, the ramp threshold is set based on the actual vehicle driving system in the early stages, typically set to 2%. Taking a preset cycle of ten cycles and a ramp threshold of 2% as an example: If the vehicle's gradient value is less than or equal to 2% for ten cycles, the current road driving environment is considered to be a flat road surface. If the vehicle's gradient value is greater than 2% within ten cycles, the current road driving environment is considered to be a sloping road surface, and an automatic parking command is triggered until the vehicle completes the reversal, at which point the vehicle's gradient value for the cycle is recalculated.

[0049] The set number of times is one. If the number of times the vehicle's slope value exceeds the slope threshold and the number of times it is less than the slope threshold both exceed one within ten cycles, it indicates that the vehicle's slope value is fluctuating and the vehicle is on a road surface that changes from uphill to downhill. That is, there are situations where the vehicle changes from a flat road surface to a slope, or from a slope to a flat road surface.

[0050] S2: The drive motor provides torque to the vehicle in the second direction to drive the vehicle speed to gradually decrease from the positive speed in the first direction to 0, and when the positive speed of the vehicle in the first direction is 0, the torque in the second direction is not 0.

[0051] S201: In response to an automatic parking command, while the vehicle is traveling in a first direction, shift to a gear corresponding to a second direction opposite to the first direction, and perform a reverse correction on the vehicle's driving state, wherein the vehicle's driving state includes at least the vehicle speed.

[0052] When responding to an automatic parking command, the vehicle shifts to the gear corresponding to the second direction opposite to the first direction while it is traveling in the first direction. Similarly, in order to prevent the vehicle from being mistaken for rolling backward and triggering other logic, the vehicle's driving state also needs to be corrected in the opposite direction so that the actual positive or negative value of the vehicle's driving state corresponds to the second direction.

[0053] The vehicle's driving status includes at least its speed. Before the vehicle responds to the automatic parking signal, it decelerates in the first direction. At this time, the vehicle speed is positive in the first direction and gradually decreases. However, when the vehicle shifts to the gear corresponding to the second direction, it still maintains a positive speed in the first direction, which is opposite to the actual gear position. Therefore, in order to prevent the vehicle from being mistaken for rolling backward and triggering other logic, the vehicle speed data is reversed at this time so that the vehicle speed data changes from a positive speed in the first direction to a negative speed in the first direction, so that the vehicle speed can correspond to the vehicle's operating status in the actual gear position at this time.

[0054] S202: Obtain the vehicle slope value, and based on the vehicle slope value, calculate the torque provided by the drive motor for the vehicle to travel in the second direction; S202(a): If all instantaneous ramp values ​​are less than or equal to the ramp threshold within the preset period, then the vehicle ramp value is 0. S202(b): If all instantaneous ramp values ​​are greater than the ramp threshold within the preset period, then the instantaneous ramp value corresponding to the last period shall be used as the vehicle ramp value.

[0055] Taking a preset cycle of ten cycles and a ramp threshold of 2% as an example: If all instantaneous gradient values ​​within ten cycles are less than or equal to 2%, then the vehicle is on a flat road surface and the vehicle gradient value is 0. If all instantaneous gradient values ​​are greater than the gradient threshold within ten cycles, and the instantaneous gradient value of the tenth cycle is 15%, then the vehicle is on the slope surface at this time, and the vehicle's gradient value is 15%.

[0056] Furthermore, in the actual testing process, the vehicle slope value can be positive or negative. If the vehicle slope value is positive, it means that the vehicle slope is the same as the vehicle's first direction, and the vehicle is in an uphill state. If the vehicle slope value is negative, it means that the vehicle slope is opposite to the vehicle's first direction, and the vehicle is in a downhill state.

[0057] S203(a): If the vehicle's slope value is 0, the reverse correction of the vehicle's driving state includes: If the vehicle's gradient is 0, then the vehicle is on a flat road surface. The vehicle speed data is then processed in reverse to change it from a positive speed in the first direction to a negative speed in the first direction. Specifically, the vehicle speed data is multiplied by 1, thus achieving the reverse processing of the vehicle speed data.

[0058] S203(b): If the instantaneous ramp value corresponding to the last cycle is used as the vehicle ramp value, then the vehicle driving state also includes the vehicle ramp value, and the reverse correction of the vehicle driving state includes: The vehicle speed and vehicle gradient values ​​are reversed so that the vehicle speed data changes from a positive speed in the first direction to a negative speed in the first direction, and the vehicle gradient value data changes from a positive vehicle gradient value in the first direction to a negative vehicle gradient value in the first direction.

[0059] If the instantaneous slope value corresponding to the last cycle is taken as the vehicle's slope value, then the vehicle is on the slope surface at this time. The slope value data is processed in reverse so that the vehicle's slope value data changes from a positive vehicle slope value in the first direction to a negative vehicle slope value in the first direction.

[0060] Taking a vehicle moving uphill in the first direction as an example, before the vehicle responds to the automatic parking signal, the vehicle decelerates uphill in the first direction. At this time, the vehicle's slope value in the first direction is a positive slope value, i.e., uphill. However, when the vehicle shifts to the gear corresponding to the second direction, which corresponds to a downhill section, the vehicle still maintains a positive speed and positive slope value in the first direction, which is opposite to the actual gear position. Therefore, in order to prevent it from being mistaken for the vehicle rolling downhill and triggering other logic, the vehicle speed and slope value data are reversed at this time, so that the vehicle speed and slope value data change from positive speed and positive slope value in the first direction to negative speed and negative slope value in the first direction, i.e., the vehicle is in a downhill state corresponding to the actual gear position at this time.

[0061] Similarly, if the vehicle is going downhill in the first direction, the slope value is positive in the first direction. However, when the vehicle shifts to the gear corresponding to the second direction, which corresponds to an uphill section, the vehicle still maintains the positive speed and slope value in the first direction, which is opposite to the actual gear position. Therefore, to prevent it from being mistaken for rolling backward and triggering other logic, the vehicle speed and slope value data are reversed so that the vehicle speed and slope value data change from positive speed and positive slope value in the first direction to negative speed and negative slope value in the first direction, which corresponds to the uphill state of the vehicle in the actual gear position at this time.

[0062] S204(a): If the vehicle is on a flat road surface, the drive motor provides torque to the vehicle in the second direction, including: Based on the distance the vehicle travels to the parking point in the first direction and the vehicle speed, the torque for traveling in the second direction is calculated.

[0063] When the vehicle is on a flat road, it is only affected by the braking force in the first direction to decelerate. When the vehicle shifts gears, the torque in the second direction is calculated. Since the torque in the second direction is opposite to the actual direction of travel of the vehicle in the first direction, the braking force is quickly unloaded at this time, and the drive motor provides the torque in the second direction to the vehicle, so that the torque in the second direction replaces the original braking force in the first direction to decelerate the vehicle.

[0064] When the vehicle is affected by torque in the second direction, causing its speed in the first direction to gradually decrease to 0, the vehicle completes the reversal of its driving direction. That is, the vehicle's driving direction corresponds to its actual gear position, which is considered a dynamic gear shift. Furthermore, the vehicle is still subjected to torque in the second direction; although the vehicle speed is 0, the acceleration in the second direction is not zero. Therefore, under the influence of the torque in the second direction, the vehicle immediately reverses, thus maintaining its driving state throughout the entire reversing process without needing to come to a complete stop, thereby achieving dynamic gear shifting.

[0065] S204(b): If the vehicle is located on a sloping road surface, the drive motor provides the vehicle with torque for travel in the second direction, which includes the following steps: S204(b)(1): Obtain the slope compensation force of the vehicle along the first direction at the current slope value; When a vehicle is traveling on a slope, its own weight affects its performance, thus requiring additional slope compensation force. Slopes include both uphill and downhill sections.

[0066] Specifically, the slope compensation force in the first direction is calculated based on the vehicle's weight and the absolute value of the current slope value.

[0067] If the vehicle is on an uphill slope in the first direction before shifting gears, the driving force provides slope compensation force and decelerates the vehicle; if the vehicle is on a downhill slope in the first direction before shifting gears, the braking force provides slope compensation force and decelerates the vehicle.

[0068] Taking an uphill position in the first direction before shifting gears as an example, the vehicle's direction of travel is opposite to the direction of the gravitational component at the current slope. Since the gravitational component causes the vehicle to decelerate uphill, to prevent excessive deceleration, the electric motor needs to provide forward torque to compensate. Therefore, the positive torque provided by the motor in the first direction provides slope compensation force and decelerates the vehicle. It should be understood that the slope compensation force at this time should be less than the gravitational component so that the vehicle speed decreases and eventually reverses.

[0069] When the vehicle shifts gears, the gear is in the second direction, switching to a downhill state. At this time, after correcting the values ​​of the vehicle's slope and speed, both the slope and speed are negative in the first direction. The component of gravity of the vehicle is also negative due to the positive or negative value of the slope. Therefore, when the vehicle is stationary, the slope compensation force required after shifting gears is the same in value but opposite in sign to the slope compensation force before shifting gears, resulting in a sharp reversal in the required torque.

[0070] For example, when the vehicle is in an uphill position before shifting gears, the vehicle's slope is +10° and the gravitational force is -500N. The positive torque provided by the motor serves as the slope compensation force, and the torque should be less than +500N and gradually decrease until the vehicle stops in the first direction. For example, the torque in the first direction of the vehicle is +400N and gradually decreases, so that the vehicle's speed in the first direction gradually decreases. When the vehicle responds to a parking command, it shifts to the second direction, i.e., the downhill direction. The vehicle's slope is corrected to -10°. At this point, the gravitational component is +500N. The required slope compensation force should be less than -500N and gradually decrease. For example, the torque provided by the motor in the first direction is -400N and gradually decreases. That is, the motor should provide the second direction so that the vehicle can rely on the gravitational component, which is greater than the positive torque, to achieve a speed of 0 in the first direction. Since the gravitational component is always greater than the positive torque provided by the motor, the vehicle can continue to travel in the second direction after its speed reaches 0 in the first direction, relying on the gravitational component, thus completing the reversal of the vehicle.

[0071] When responding to a parking command, the vehicle's driving force switches from +400N to -400N, involving a sharp reversal in torque direction. If the switch were direct, the drive motor would be subjected to a huge reverse impact, leading to severe jerking or even mechanical damage. Therefore, to cope with the sharp reversal in torque demand and ensure the smoothness of torque changes, preventing the vehicle from triggering the rollover logic, a fifth-order polynomial model is used to calculate torque for sloping roads.

[0072] S204(b)(2): Based on vehicle travel time and motor torque, establish a fifth-order polynomial model; The fifth-order polynomial model, by defining a torque curve, not only ensures numerical matching at the start and end points, but also constrains both its first derivative (torque change rate, i.e., vehicle speed) and second derivative (i.e., vehicle acceleration) to zero, thus uniquely determining a high-order, continuous, and smooth curve. This curve ensures that the torque reversal process from driving to braking is gradual and smooth, fundamentally eliminating the shock caused by sudden torque changes.

[0073] Based on the driving time t after the vehicle responds to the automatic parking command and the corresponding torque T(t) at that time, a fifth-order polynomial model is established: T(t) = a0+ a1·t + a2·t² + a3·t³ + a4·t 4 + a5·t 5 ; If the vehicle is on a downhill slope in the first direction before shifting gears, the braking force provides slope compensation and decelerates the vehicle. In this application, when the vehicle responds to a parking signal, the vehicle shifts gears. At this time, the torque in the second direction provided by the motor replaces the braking force to decelerate the vehicle. Similar to when the vehicle is on an uphill slope, this involves a sharp change in the direction of torque, and a fifth-order polynomial model is established to calculate the torque.

[0074] S204(b)(3): Obtain the first slope compensation force, vehicle speed and vehicle acceleration of the vehicle along the first direction at the current slope value; S204(b)(4): The second slope compensation force in the second direction of the vehicle at the moment of gear shift is taken as the target force, and the target vehicle speed and target acceleration when the vehicle is under the target force are obtained; S204(b)(5): Using the target force, target speed, target acceleration, and the vehicle's slope compensation force, vehicle speed, and vehicle acceleration in the first direction as boundary conditions in the fifth-order polynomial model, calculate the coefficients of each term in the fifth-order polynomial model and obtain the fifth-order polynomial calculation formula. Specifically, the fifth-order polynomial calculation formula is calculated using the first slope compensation force, vehicle speed, and vehicle acceleration when the vehicle responds to the parking signal, as well as the target force, target speed, and target acceleration in the second direction at the moment of gear shifting, as boundary conditions.

[0075] For example, before shifting gears, the gravitational force is -500N, the slope compensation force is +400N, and after shifting gears, when the vehicle is stationary, the slope compensation force is -500N. Simultaneously, the change is seamless, and target torque control is performed based on a fifth-order polynomial. T(t)=a0+a1·t+a2·t²+a3·t³+a4·t 4 +a5·t 5 ; Where T(t) is the torque value at time t; t is time, from 0 to Tf is the total transition time from the vehicle responding to the parking signal to completing the vehicle reversal, and a0 to a5 are coefficients to be determined.

[0076] Boundary conditions: At t = 0: T(0) = +400 T'(0) =0 T''(0) =0 At t=Tf: T(Tf) = -400 T'(Tf) = 0 T''(Tf) = 0 Based on the boundary conditions, solve for all coefficients: a0 = +500; a1 = 0; a2 = 0; a3 = +1000 / Tf³; a4 = -1500 / Tf 4 ; a5 = +600 / Tf 5 The final calculation formula is: T(t) = 500+1000·(t / Tf)³-1500·(t / Tf) 4 +600·(t / Tf) 5 S204(b)(6): Based on the fifth-order polynomial calculation formula, obtain the torque variation curve of the drive motor for the vehicle to travel in the second direction.

[0077] This application also provides a dynamic shifting system for automatic parking, comprising: The first module is used to send parking signals; The second module includes a dynamic shift state machine, which is used to respond to a parking signal and shift gears to the corresponding gear in the second direction opposite to the first direction when the vehicle is traveling in the first direction. The third module is used to drive the motor to provide torque for the vehicle to travel in the second direction, so as to drive the vehicle speed to gradually decrease from the positive speed in the first direction to 0, and when the positive speed of the vehicle in the first direction is 0, the torque in the second direction is not 0.

[0078] Furthermore, this application also provides a dynamic shifting device for automatic parking, the dynamic shifting device for automatic parking including a processor, a memory, and a dynamic shifting program for automatic parking stored in the memory and executable by the processor, wherein when the dynamic shifting program for automatic parking is executed by the processor, the steps of the dynamic shifting method for automatic parking described above are implemented.

[0079] Furthermore, this application also provides a computer-readable storage medium, characterized in that the computer-readable storage medium stores a dynamic shifting program for automatic parking, wherein when the dynamic shifting program for automatic parking is executed by a processor, it implements the steps of the dynamic shifting method for automatic parking described above.

[0080] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0081] It should be noted that in this application, relational terms such as "first" and "second" are used merely 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.

[0082] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement 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 claimed herein.

Claims

1. An automatic parking dynamic gear shifting method, characterized in that, It includes: In response to an automatic parking command, while the vehicle is traveling in a first direction, the gear is shifted to the gear corresponding to the second direction opposite to the first direction, wherein the first direction is the forward direction and the second direction is the reverse direction; The drive motor provides torque to the vehicle in the second direction to drive the vehicle speed to gradually decrease from the positive speed in the first direction to 0, and when the positive speed of the vehicle in the first direction is 0, the torque in the second direction is not 0.

2. The automatic parking dynamic gear shifting method as described in claim 1, characterized in that: Before responding to the automatic parking command and shifting gears to the corresponding gear in the second direction opposite to the first direction while the vehicle is traveling in the first direction, the method further includes: Detect whether the vehicle has a slope value, and obtain the vehicle speed in the first direction and the parking point in the first direction; If a vehicle slope exists, and the vehicle speed is lower than the preset speed value but greater than zero, and the distance the vehicle travels to the parking point in the first direction is less than the first distance, then an automatic parking command will be executed. If there is no vehicle slope value, the vehicle enters a static shift state.

3. The automatic parking dynamic gear shifting method as described in claim 2, characterized in that: If a vehicle slope exists, and the vehicle speed is lower than a preset speed value but greater than zero, and the distance the vehicle travels to the parking point in the first direction is less than a first distance, then responding to the automatic parking command further includes: If a vehicle slope exists and the vehicle speed is higher than the preset speed value, and / or the distance the vehicle travels to the parking point in the first direction is greater than a first distance, then the vehicle will maintain its driving state in the first direction until the vehicle speed is lower than the preset speed value and greater than zero, and the distance the vehicle travels to the parking point in the first direction is less than the first distance, and then the automatic parking command will be responded to.

4. The automatic parking dynamic gear shifting method as described in claim 2, characterized in that... : The detection of whether a vehicle has a slope value includes: The vehicle slope value is detected within a preset period, and the instantaneous slope value of the vehicle within each period is obtained. If, within a preset period, all instantaneous slope values ​​are less than or equal to the slope threshold, or all instantaneous slope values ​​are greater than the slope threshold, then the vehicle has a vehicle slope value. If, within a preset period, the number of times each instantaneous slope value exceeds the slope threshold and the number of times it falls below the slope threshold both exceed the set number, then the vehicle will not have a vehicle slope value.

5. The automatic parking dynamic gear shifting method as described in claim 4, characterized in that: The method of responding to an automatic parking command and shifting gears to a gear corresponding to a second direction opposite to the first direction while the vehicle is traveling in a first direction further includes: In response to an automatic parking command, while the vehicle is traveling in a first direction, the gear is shifted to the gear corresponding to the second direction opposite to the first direction, and the vehicle's driving state is corrected in the opposite direction, wherein the vehicle's driving state includes at least the vehicle speed.

6. The automatic parking dynamic gear shifting method as described in claim 5, characterized in that: The drive motor provides the vehicle with torque for travel in the second direction, and includes: Get the vehicle's ramp value; Based on the vehicle's gradient, the torque provided by the drive motor for the vehicle to travel in the second direction is calculated.

7. The automatic parking dynamic gear shifting method as described in claim 6, characterized in that: The acquisition of the vehicle ramp value includes: If all instantaneous slope values ​​are less than or equal to the slope threshold within the preset period, then the vehicle slope value is 0. If all instantaneous ramp values ​​are greater than the ramp threshold within the preset period, then the instantaneous ramp value corresponding to the last period will be used as the vehicle ramp value.

8. The automatic parking dynamic gear shifting method as described in claim 7, characterized in that: If the vehicle's slope value is 0, the reverse correction of the vehicle's driving state includes: The vehicle speed data is processed in reverse so that the vehicle speed data changes from a positive speed in the first direction to a negative speed in the first direction.

9. The automatic parking dynamic gear shifting method as described in claim 8, characterized in that: The drive motor provides the vehicle with torque for travel in the second direction, and includes: When responding to an automatic parking command, the torque is calculated based on the vehicle's travel distance to the parking point in the first direction and the vehicle's speed.

10. The automatic parking dynamic gear shifting method as described in claim 9, characterized in that: If the instantaneous ramp value corresponding to the last cycle is used as the vehicle ramp value, then the vehicle driving state also includes the vehicle ramp value. The reverse correction of the vehicle driving state includes: The vehicle speed and vehicle gradient data are reversed so that the vehicle speed data changes from a positive speed in the first direction to a negative speed in the first direction, and the vehicle gradient data changes from a positive vehicle gradient value in the first direction to a negative vehicle gradient value in the first direction.

11. The automatic parking dynamic gear shifting method as described in claim 10, characterized in that: The drive motor provides the vehicle with torque for travel in the second direction, and includes: A fifth-order polynomial model is established based on vehicle travel time and real-time motor torque. Obtain the slope compensation force, rate of change, and acceleration of the vehicle along the first direction at the current vehicle slope value; The second slope compensation force in the second direction at the moment of gear shift is taken as the target force, and the target rate of change and target acceleration of the vehicle when it is under the target force are obtained; Using the target force, target speed, target acceleration, and the vehicle's slope compensation force, vehicle speed, and vehicle acceleration in the first direction as boundary conditions in the fifth-order polynomial model, the coefficients of each term in the fifth-order polynomial model are calculated to obtain the fifth-order polynomial calculation formula. Based on the fifth-order polynomial calculation formula, the torque variation curve of the drive motor for the vehicle to travel in the second direction is obtained.

12. The automatic parking dynamic gear shifting method as described in claim 11, characterized in that: The step of obtaining the slope compensation force of the vehicle along the first direction at the current slope value includes: Calculate the slope compensation force in the first direction based on the vehicle's weight and the absolute value of the current slope.

13. An automatic parking dynamic shifting system, characterized in that, It includes: The first module is used to send parking signals; The second module is used to respond to a parking signal and shift gears to the corresponding gear in the second direction opposite to the first direction while the vehicle is traveling in the first direction. The third module is used to drive the motor to provide torque for the vehicle to travel in the second direction, so as to drive the vehicle speed to gradually decrease from the positive speed in the first direction to 0, and when the positive speed of the vehicle in the first direction is 0, the torque in the second direction is not 0.

14. An automatic parking dynamic gear shifting device, characterized in that, The automatic parking dynamic shifting device includes a processor, a memory, and an automatic parking dynamic shifting program stored in the memory and executable by the processor, wherein when the automatic parking dynamic shifting program is executed by the processor, it implements the steps of the automatic parking dynamic shifting method as described in any one of claims 1 to 12.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a dynamic shifting program for automatic parking, wherein when the automatic parking dynamic shifting program is executed by a processor, it implements the steps of the automatic parking dynamic shifting method as described in any one of claims 1 to 12.

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