Control method for an electric vehicle, vehicle controller and electric vehicle

Abstract

A control method, vehicle controller, and electric vehicle for electric vehicles are disclosed, relating to the field of new energy vehicles and applicable to pure electric vehicles and hybrid vehicles. The control method coordinates the rear-wheel steering system and drive system to achieve wall-hugging driving. The method includes, while driving at a speed lower than a preset speed, after the steering wheel begins to turn right, controlling the rear-wheel steering system to drive the two rear wheels to turn right along with the two front wheels. After the two rear wheels have turned right along with the two front wheels, and the accelerator pedal opening increases, controlling the drive system to output a first positive torque to drive the electric vehicle to move laterally to the right. After moving laterally to the right until the distance to the wall on the right side of the road is less than a preset distance, controlling the drive system to output a second positive torque greater than the first positive torque to cause the two right wheels to lift off the ground and contact the wall. According to this solution, the ability to graze walls is improved, enhancing the vehicle's practicality and providing sufficient emotional value for the driver.

Description

Technical Field

[0001] This application relates to the field of electric vehicles, and more specifically, to a powertrain, a control method, and an electric vehicle. Background Technology

[0002] With the development of electric vehicle technology, rear-wheel steering (RWS) has provided more possibilities for the control of electric vehicles. Rear-wheel steering is also known as active rear-wheel steering or four-wheel steering (4WS). The rear-wheel steering system adjusts the rear wheel deflection angle in real time through an electronic control unit. Currently, electric vehicles equipped with rear-wheel steering systems control the rear wheels to deflect in the opposite direction to the front wheels at low speeds to reduce the vehicle's turning radius and improve the ease of turning, thereby enhancing parking and narrow-road maneuverability. At high speeds, the rear wheels deflect in the same direction as the front wheels to enhance lane-changing stability and improve the accuracy of rapid lane changes. However, in some special scenarios, such as narrow road encounters on mountain roads or narrow roads in old urban areas, controlling the rear wheels to deflect in the opposite direction to the front wheels cannot improve the electric vehicle's ability to pass through narrow spaces; the electric vehicle must then hug the wall to pass.

[0003] Therefore, improving the ability of electric vehicles to drive close to walls is a problem that needs to be solved. Summary of the Invention

[0004] This application provides a control method, a vehicle controller, and an electric vehicle for electric vehicles. In some scenarios, the rear-wheel steering system enables the rear wheels to steer in the same direction as the front wheels, allowing the two right wheels to contact the wall, increasing friction, and enabling one side to smoothly climb the wall. This reduces the width of the road surface occupied by the electric vehicle, and allows for smooth operation such as passing on narrow roads. It simplifies the operation of driving close to the wall, improves the ability of electric vehicles to pass close to the wall in special scenarios, enhances the practical value of the vehicle, and provides sufficient emotional value for the driver.

[0005] Firstly, this application provides a control method for an electric vehicle. The method controls the rear-wheel steering system and drive system of the electric vehicle to cooperate in achieving wall-hugging travel. The control method includes, while the electric vehicle is traveling at a speed lower than a preset speed, after the steering wheel of the electric vehicle begins to turn to the right, controlling the rear-wheel steering system to drive the two rear wheels to turn to the right along with the two front wheels. After the two rear wheels have turned to the right along with the two front wheels, and after the accelerator pedal opening of the electric vehicle increases, controlling the drive system to output a first positive torque to drive the electric vehicle to move laterally to the right. After the electric vehicle has moved laterally to the right until the distance between it and the wall on the right side of the road is less than a preset distance, controlling the drive system to output a second positive torque greater than the first positive torque to cause the two right wheels of the electric vehicle to leave the ground and abut against the wall.

[0006] The rear-wheel steering system of electric vehicles is used to change the rotation angle and orientation of the two rear wheels, thereby effectively adjusting the vehicle's steering and handling characteristics through different steering methods. For existing electric vehicles, at low speeds, the rear wheels steer in the opposite direction to the front wheels, reducing the turning radius and improving the overall handling and agility of the vehicle. At higher speeds, the rear wheels steer in the same direction as the front wheels, effectively reducing the yaw moment generated by steering operations and enhancing vehicle stability. However, in some special scenarios, such as passing on narrow mountain roads or avoiding obstacles on narrow roads in old urban areas, it is necessary to reduce the width of the road occupied by the electric vehicle to achieve smooth passage. In these situations, at low speeds, the rear wheels steer in the opposite direction to the front wheels, which fails to reduce the width of the road occupied, and cannot handle the passage requirements in these special scenarios.

[0007] It should be understood that the narrow roads in this application include narrow driving surfaces with walls on both sides, and narrow driving surfaces with a wall on one side that prevents driving on the other side, such as mountain roads and narrow alleys in urban areas. To enable climbing over walls and reduce the width of the road surface occupied, a climbable wall is required on one side of the narrow road. The walls in this application include building walls, mountain slopes, roadside retaining walls, protective slopes, curbs, and other sloping or vertical surfaces. These walls can be man-made or naturally formed. The wall forms a certain angle with the road surface and has a certain height relative to the road surface. Under normal driving conditions, vehicles only travel on the road surface and will not drive onto the wall.

[0008] When the electric vehicle is traveling at a speed lower than the preset speed, after the steering wheel begins to turn to the right, both front and rear wheels are controlled to turn to the right. When traversing narrow roads or driving close to walls, the electric vehicle's speed should not be too high; it should be maintained at a low speed to avoid scrapes and collisions. When the electric vehicle is traveling at a speed lower than the preset speed, after the steering wheel turns to the right, the front wheels turn to the right, and the rear wheels follow suit. At this time, the rear-wheel steering system controls the front and rear wheels to turn in the same direction. In narrow road scenarios, the electric vehicle needs to stay as close to the wall as possible to minimize the width it occupies. By turning both front and rear wheels to the right simultaneously, the electric vehicle can steer more precisely to the right, providing the initial conditions for subsequent wall-climbing maneuvers.

[0009] The accelerator pedal in this application can also be referred to as the power pedal or accelerator pedal. The opening degree of the accelerator pedal indicates the amount of driving force required by the driver. The larger the opening degree of the accelerator pedal, the greater the driver's demand for driving force, and the greater the torque required from the drive motor. A larger accelerator pedal opening results in a greater torque output from the drive motor, and a smaller accelerator pedal opening results in a smaller torque output from the drive motor. The torque output by the drive motor varies with the opening degree of the accelerator pedal.

[0010] After the accelerator pedal of the electric vehicle is opened wider, the drive system is then controlled to rotate the wheels. When the driver depresses the accelerator pedal, the drive system outputs a first positive torque to rotate the wheels, causing the electric vehicle to laterally move to the right. It should be understood that lateral movement to the right can refer to the electric vehicle moving diagonally forward to the right. In this state, the vehicle's orientation remains unchanged, and the vehicle does not rotate. After both front and rear wheels turn to the right, the electric vehicle moves to the right, thus moving parallel to the wall and approaching it on the right side of the road. When the electric vehicle has laterally moved to the right until the distance to the wall on the right side of the road is less than a preset distance, the vehicle is sufficiently close to the wall. Because both front and rear wheels are turning to the right, both right wheels are in contact with the wall, resulting in a large contact area and balanced front-to-rear forces. If the front and rear wheels rotate in opposite directions, then when the electric vehicle turns, only the front or rear wheels will contact the wall, resulting in a small contact area and unbalanced front-to-rear forces, making it difficult for the electric vehicle to climb the wall. After both right wheels make contact with the wall, the drive system outputs a second positive torque greater than the first positive torque. This causes the right wheels of the electric vehicle to gradually move upwards along the wall, until the two right wheels are no longer in contact with the road surface and are pressed against the right side of the wall. The two right wheels then detach from the road surface and remain in contact with the wall. Because the right wheels need to be driven to gradually move upwards along the wall, the second positive torque output by the drive system must be greater than the torque used when driving on a flat road. Through the coordinated steering of the front and rear wheels and the drive system, the two right wheels of the electric vehicle can stably adhere to the wall surface, increasing the contact area and friction between the right wheels and the wall, thus helping the vehicle to successfully complete the wall-climbing maneuver. The drive system drives the wheels to rotate along the wall, causing the two right wheels of the electric vehicle to travel to the wall on the right side of the road surface, so that the horizontal height of the two right wheels is higher than that of the two left wheels. Using the force of the wheel rotation, the right side of the electric vehicle climbs onto the wall, thereby reducing the width of the road surface occupied by the electric vehicle.

[0011] It should be understood that this application describes the situation as vehicles all driving on the right. Therefore, when an electric vehicle is driving close to a wall to pass through a narrow road or to meet oncoming traffic, the right wheel of the electric vehicle is usually driven onto the wall on the right side of the road. For roads where vehicles all drive on the left or where there is only a usable wall on the left side of the road, both the front and rear wheels of the electric vehicle turn to the left, causing the left wheel of the electric vehicle to drive onto the wall on the left side of the road. The actions are modified accordingly, and the direction of rotation is reversed. This will not be elaborated further in this document.

[0012] According to the solution of this application, by coordinating the steering of the rear wheels and the front wheels and the drive system, electric vehicles can more easily adhere to the wall and complete the wall-climbing action, thereby smoothly passing through narrow roads. This simplifies the driver's operation process in narrow road meeting scenarios, reduces driving difficulty, improves the vehicle's ability to pass through narrow road scenarios, enhances the driver's control and operational convenience, and significantly improves the driver's satisfaction and experience when using the vehicle.

[0013] In one implementation, the control method is used to control the rear wheel steering system and drive system of the electric vehicle to cooperate with each other to enable the electric vehicle to drive close to the wall after the narrow road passage function of the electric vehicle is activated.

[0014] The electric vehicle is equipped with a narrow-road passage function, which assists the electric vehicle in navigating narrow roads by adjusting the control method. In certain special scenarios, after the narrow-road passage function is activated, the electric vehicle can use the wall beside the road to pass through narrow roads. One side of the electric vehicle climbs the wall to reduce the width of the road it occupies, thus enabling it to pass through the narrow road. When the narrow-road passage function is activated, the rear-wheel steering system and the drive system work together to make the electric vehicle travel close to the wall to pass through narrow roads.

[0015] When the narrow-road passage function of the electric vehicle is not activated, if the vehicle speed is lower than the preset speed, the rear wheels are controlled to turn in the opposite direction to the steering wheel. When the narrow-road passage function is activated, if the vehicle speed is lower than the preset speed, the rear wheels are controlled to turn in the same direction as the steering wheel.

[0016] In conjunction with the first aspect, in some implementations of the first aspect, the electric vehicle is used to control the electric vehicle to activate the narrow road passage function by touching the central control screen of the electric vehicle or activating the narrow road passage function button.

[0017] It should be understood that the narrow-road passage function of electric vehicles usually requires manual activation by the driver. Because the electric vehicle is in an unconventional driving state when using this function to pass through narrow roads, the driver needs to confirm in advance whether narrow-road passage is permissible and allow the driver and passengers to prepare accordingly to avoid panic and misoperation. When the electric vehicle is in intelligent driving mode, if the intelligent driving system detects a narrow road ahead, it also needs to prompt the driver to activate the narrow-road passage function. Only after the driver confirms activation can intelligent driving continue or the driver take over.

[0018] In one possible embodiment, the electric vehicle includes a narrow-road passage function button. When the narrow-road passage function button is off, the electric vehicle controls the rear wheels to rotate in the opposite direction to the steering wheel when the vehicle speed is less than a preset speed. When the narrow-road passage function button is on, the electric vehicle activates the narrow-road passage function, and when the vehicle speed is less than the preset speed, the electric vehicle controls the rear wheels to rotate in the same direction as the steering wheel.

[0019] Electric vehicles are equipped with a narrow-road passage function button for driver operation. For example, the narrow-road passage function button is a physical button, which the driver presses to activate the narrow-road passage function. Alternatively, the narrow-road passage function button can be a virtual button on the central control screen, which the driver activates by selecting the narrow-road passage function mode. Furthermore, the narrow-road passage function button can also be indirectly configured, for example, integrated into the rear-wheel steering button or other function buttons. This application does not limit the method or form of the narrow-road passage function button.

[0020] In conjunction with the first aspect, in some implementations of the first aspect, the control method further includes, after the two right wheels of the electric vehicle have left the ground and are in contact with the wall, controlling the drive system to stop outputting torque as the steering wheel begins to turn to the left. After the steering wheel turns to the left, controlling the drive system to output a third positive torque, less than the second positive torque, to drive the electric vehicle to travel along the wall.

[0021] Guided by the right-hand wheels turning to the right, the electric vehicle will climb the wall. As the two right wheels press against the wall and ascend, they leave the ground, while the two left wheels make contact, completing the wall-climbing maneuver and achieving wall-hugging travel. At this point, the electric vehicle's footprint on the ground is reduced. Different strategies can be employed to navigate different scenarios.

[0022] In one embodiment, the electric vehicle needs to actively traverse the narrow road. After completing the wall-climbing maneuver, the electric vehicle needs to maintain its wall-climbing posture and continue driving along the wall to pass through the narrow road. Once the electric vehicle has completed the wall-climbing maneuver and its two right wheels are in contact with the wall on the right side of the narrow road, the steering wheel is turned to the left to straighten it. This causes the two right wheels of the electric vehicle to no longer point upwards towards the wall, and the horizontal height to stop increasing; instead, they point forward along the wall. The drive system outputs a third positive torque, less than the second positive torque, to drive the electric vehicle to travel along the wall, maintaining the posture of its two left wheels on the road surface and its two right wheels on the wall.

[0023] According to the solution in this application, after the electric vehicle completes the wall-climbing action, the wheels are controlled to return to the center to prepare for the subsequent actions of the electric vehicle. The drive system drives the wheels to rotate while keeping them in contact with the wall, thereby controlling the electric vehicle to maintain the wall-climbing state and move forward. This improves the electric vehicle's ability to pass through narrow road scenarios, simplifies the driver's operation process for climbing walls, reduces driving difficulty, and enhances the driving experience.

[0024] In conjunction with the first aspect, in some implementations of the first aspect, the control method specifically includes controlling the braking system to output braking force to all four wheels after the steering wheel is turned to the left and straightened.

[0025] In another embodiment, the electric vehicle does not need to actively traverse the narrow road. For example, in a scenario where oncoming traffic meets on a narrow road, after completing the wall-climbing maneuver, the electric vehicle can choose to remain stationary while climbing, waiting for the oncoming vehicle to pass before proceeding. Once the electric vehicle has completed the wall-climbing maneuver and its two right wheels are in contact with the right side of the wall, the steering wheel is turned to the left to straighten it. This prevents the two right wheels from pointing upwards from the wall and stops increasing their horizontal height; instead, they point forward along the wall. After the steering wheel is turned to the left, the drive system stops outputting torque, and the electric vehicle remains stationary or brakes, waiting for the oncoming vehicle to pass before descending the wall. Straightening the wheels improves the stability of the electric vehicle while climbing the wall and prepares it for subsequent maneuvers.

[0026] In conjunction with the first aspect, in some implementations of the first aspect, the control method further includes controlling the drive system to output reverse torque to drive the electric vehicle to reverse and reduce the ground clearance of the two right wheels after controlling the electric vehicle to travel a distance greater than a preset distance along the wall and after the steering wheel is turned to the right to a angle greater than a preset angle.

[0027] After the electric vehicle has traveled a distance closer to the wall than a preset distance and the steering wheel has been turned to the right to a angle greater than a preset angle, the electric vehicle has completed the wall-climbing maneuver. For example, after the electric vehicle has passed through a narrow road, the vehicle is controlled to return to the road surface. After the steering wheel is turned to the right to a angle greater than a preset angle, the front wheels and both rear wheels are controlled to turn to the right, achieving the same state as when climbing the wall. At the same time, the drive system is controlled to output reverse torque, causing the wheels to rotate in the opposite direction. The electric vehicle reverses, thus causing the two right wheels to disengage from the wall and return to the road surface.

[0028] According to the solution in this application, after the electric vehicle passes through a narrow road, the wheels are controlled to turn to the right, and the drive system is controlled to drive the electric vehicle in reverse, thereby disengaging from the wall-climbing state and safely returning to the surface of the narrow road. Driving down the wall in reverse follows a similar path to the wall-climbing process, avoiding deviation or instability of the electric vehicle due to inconsistent directions.

[0029] In conjunction with the first aspect, in some implementations of the first aspect, the control method further includes, after controlling the electric vehicle to travel a distance closer to the wall than a preset distance and after the steering wheel is turned to the left to a angle greater than a preset angle, the braking drive system outputs positive torque to drive the electric vehicle forward and the ground clearance of the two right wheels is reduced.

[0030] After the electric vehicle has traveled a distance closer to the wall than a preset distance and the steering wheel has been turned to the right to a angle greater than a preset angle, the electric vehicle has completed the wall-climbing maneuver. For example, after the electric vehicle has passed through a narrow road, it is controlled to return to the road surface. After the steering wheel is turned to the left to a angle greater than a preset angle, the front wheels and both rear wheels are controlled to turn to the left, and the drive system continues to output positive torque, propelling the electric vehicle forward. This causes the two right wheels to detach from the wall and return to the road surface.

[0031] According to the solution in this application, after the electric vehicle passes through a narrow road, the wheels are turned to the left and the drive system is controlled to propel the electric vehicle forward, thereby disengaging it from the wall-climbing state and safely returning it to the surface of the narrow road. Driving down the wall by moving forward simplifies operation and improves traffic efficiency.

[0032] In conjunction with the first aspect, in some implementations of the first aspect, the control method further includes controlling the drive system to stop outputting the reverse torque after controlling the drive system to output reverse torque to drive the electric vehicle backward and the ground clearance of the two right wheels has decreased to the point that the two rear wheels have re-contacted the road surface.

[0033] After the electric vehicle reverses and the two right wheels are removed from the wall and back onto the road, the control drive system stops outputting reverse torque to prevent the electric vehicle from continuing to reverse.

[0034] In conjunction with the first aspect, in some implementations of the first aspect, the control method further includes controlling the suspension system of the electric vehicle to increase damping after the two rear wheels turn to the right along with the two front wheels.

[0035] Increasing the damping of the suspension system refers to increasing the damping coefficient of the shock absorbers. The damping coefficient of the shock absorbers affects the vibration absorption capacity of the electric vehicle's suspension system. The suspension system is responsible for absorbing road vibrations and maintaining vehicle stability. Increasing damping can effectively reduce vibrations caused by uneven road surfaces during driving, thereby improving vehicle stability and handling. However, increasing damping also makes the suspension stiffer, causing vibrations to be transmitted to the passenger compartment when driving on uneven roads, thus reducing ride comfort. In narrow road driving scenarios, electric vehicles need to have both right wheels in contact with the wall and climb it. During this process, the electric vehicle will be affected by lateral forces, causing the vehicle to tilt or vibrate. If the suspension damping is insufficient, the electric vehicle may become unstable due to lateral swaying, affecting the smooth climbing of the wall.

[0036] According to the solution in this application, during the process of electric vehicles driving close to a wall, the stability of the electric vehicles is significantly improved by increasing the suspension damping, the swaying and tilting of the vehicle body are effectively suppressed, the driver's road feel and control are improved, and the electric vehicles are more stable when climbing or hugging the wall surface, thereby improving the traffic capacity and safety of electric vehicles.

[0037] In conjunction with the first aspect, in some implementations of the first aspect, the control method further includes, after the two rear wheels turn to the right along with the two front wheels and before the two right wheels leave the ground, controlling the suspension system of the electric vehicle to adjust the height of the right side of the electric vehicle to be greater than the height of the left side of the electric vehicle. After the two right wheels of the electric vehicle leave the ground and contact the wall, and before the steering wheel begins to return to the left, controlling the suspension system to gradually lower the height of the right side of the vehicle and gradually increase the height of the left side of the vehicle.

[0038] Before the two right wheels touch the wall, the suspension system of the electric vehicle adjusts to make the height of the right side of the vehicle greater than the height of the left side. As the vehicle moves upwards while the two right wheels are touching the wall, the suspension system gradually lowers the height of the right side of the vehicle and gradually increases the height of the left side.

[0039] For electric vehicles with adjustable ride height, such as those equipped with air suspension, hydraulic active suspension, or electromagnetic active suspension systems, dynamically adjusting the vehicle's ride height can assist in climbing walls. Before the two right wheels contact the wall, raising the right side of the vehicle prevents it from scraping against the wall and allows the two right wheels to more easily contact the wall, increasing friction and helping the vehicle climb smoothly. As the vehicle climbs while its two wheels are in contact with the wall, the suspension system dynamically adjusts the ride height on both sides, gradually lowering the right side while increasing the left side. This helps the vehicle maintain balance during the climb, reducing tilting or instability caused by the difference in wheel height. By gradually adjusting the ride height, the vehicle can complete the wall-climbing maneuver more smoothly.

[0040] According to the solution in this application, by adjusting the height of the vehicle body on both sides through the suspension system, the electric vehicle can more easily hug the wall and complete the wall climbing action, thereby driving smoothly along the wall, dynamically balancing the center of gravity distribution of the electric vehicle, ensuring that the vehicle remains stable at all times during the wall climbing process, and reducing the driver's tilt discomfort during the wall climbing process, ensuring that the electric vehicle is more stable when climbing or hugging the wall, thereby improving the electric vehicle's traffic capacity and safety, reducing driving difficulty, and enhancing the driving experience.

[0041] In conjunction with the first aspect, in some implementations of the first aspect, the control method further includes, after the steering wheel is straightened to the left, during the process of the electric vehicle traveling close to the wall, controlling the suspension system of the electric vehicle to keep the height of the right side of the electric vehicle and the height of the left side of the electric vehicle constant. As the ground clearance of the two right wheels decreases, the suspension system gradually increases the height of the right side of the vehicle and gradually decreases the height of the left side until the heights of both sides are equal.

[0042] After the steering wheel is straightened to the left, the electric vehicle drives close to the wall, with the suspension system maintaining a constant height on both sides of the vehicle. At this point, the right side of the electric vehicle is lower than the left side. As the two right wheels decrease in height, they gradually move from the wall to the road surface. The vehicle tilts and slowly straightens. The suspension system then gradually increases the height of the right side of the vehicle and decreases the height of the left side. This helps maintain balance during the descent, reducing tilting or instability caused by the decreasing height difference between the left and right wheels. By gradually adjusting the vehicle height, the electric vehicle can more smoothly complete the descent. Once the two right wheels re-contact the road, the heights of both sides are equal, and the electric vehicle returns to normal driving mode.

[0043] In conjunction with the first aspect, in some implementations of the first aspect, the control method specifically includes controlling the steering angles of the front and rear wheels to remain the same after the steering wheel begins to turn to the right and before the rightward steering angle of the rear wheels increases to a preset steering angle. After the rightward steering angle of the rear wheels increases to the preset steering angle, while the steering wheel continues to turn to the right, the rightward steering angle of the front wheels is controlled to be greater than the rightward steering angle of the rear wheels.

[0044] When the rear wheel's rightward turning angle is less than the preset turning angle, the front and rear wheel turning angles are controlled to be equal and increase as the steering wheel angle increases. When the electric vehicle is traveling at high speed, the angle of the rear wheels turning in the same direction needs to be strictly limited to avoid affecting the vehicle's stability. After the steering wheel begins to turn to the right, when the electric vehicle is traveling at low speed, the front and rear wheels turn in the same direction and maintain the same turning angle. The limitation on the rear wheel's steering angle is less, and a larger angle of rear wheel rotation will not affect the vehicle's stability. When the rear wheel's rightward turning angle is greater than the preset turning angle, the front wheel's turning angle is controlled to be greater than the rear wheel's turning angle. As the steering wheel angle increases to the right, the front wheel's rightward turning angle is increased, and the rear wheel's rightward turning angle is increased to the preset turning angle, which is less than the maximum turning angle of the rear wheels.

[0045] This preset steering angle is the rear wheel steering angle that is beneficial for electric vehicles to climb walls, or the allowable rotation angle of the rear wheels of electric vehicles when traveling at low speeds. Once the rear wheel steering angle reaches the preset angle, it no longer increases with the steering wheel rotation angle, while the front wheel steering angle continues to increase with the steering wheel rotation angle until the maximum rotation angle of the front wheels is reached.

[0046] In one embodiment, the electric vehicle prompts the driver to turn the steering wheel to a suitable angle via voice or in-vehicle screen. At this angle, the two rear wheels turn to the right to a preset angle, which makes it easier to climb walls.

[0047] It should be understood that the preset turning angle is pre-calibrated based on actual vehicle experiments and / or model calculations, or it can be pre-set by comprehensively considering the needs and performance of the entire vehicle.

[0048] According to the solution in this application, by precisely controlling the turning angle of the front and rear wheels, the electric vehicle can more smoothly adhere to the wall and complete the wall-climbing action, which improves the electric vehicle's traffic capability, simplifies the driver's operation process for controlling the electric vehicle to drive close to the wall, reduces the driving difficulty, and enhances the driving experience.

[0049] In conjunction with the first aspect, in some implementations of the first aspect, the control method specifically includes increasing the rightward turning angle of the rear wheels to a first angle when the angle between the road surface and the wall is a first slope. When the angle between the road surface and the wall is a second slope greater than the first slope, increasing the rightward turning angle of the rear wheels to a second angle less than the first angle.

[0050] Electric vehicles utilize a perception system to detect their surroundings and operational status. This system includes sensors such as cameras, lidar, and millimeter-wave radar to perceive the environment and collect and process environmental and in-vehicle information, primarily involving technologies like road boundary monitoring, vehicle detection, and pedestrian detection. Based on the acquired perception data, the electric vehicle detects information about itself and obstacles and plans its path. Perception data includes relative distance, relative speed, relative acceleration, and lane information. The electric vehicle can also detect the slope of the right-hand wall of the road, i.e., the angle between the road surface and the wall, using sensors such as cameras and radar. This angle is typically between 90 and 180 degrees.

[0051] To control an electric vehicle's wall-climbing maneuver, both rear wheels need to make full contact with the wall and generate sufficient friction. When the angle between the road surface and the wall is small, the electric vehicle requires a larger rear wheel steer angle to ensure full wheel contact and increase friction, thus helping the vehicle climb the wall smoothly. A larger steer angle helps the electric vehicle maintain a stable contact with the wall in narrow spaces. As the angle between the road surface and the wall increases, the electric vehicle's dependence on the wall decreases, requiring a smaller rear wheel steer angle. A smaller steer angle reduces the electric vehicle's excessive reliance on the wall while ensuring stable driving and avoiding the risk of instability or rollover caused by excessive steer angles.

[0052] According to the solution in this application, by dynamically adjusting the rear wheel angle based on the change in the angle between the road surface and the wall, the contact state between the electric vehicle and the wall is optimized, ensuring that the electric vehicle can successfully complete the wall climbing action under different slope conditions, thereby improving the traffic capacity of the electric vehicle, simplifying the driver's operation process for controlling the electric vehicle to drive close to the wall, reducing the driving difficulty, and enhancing the driving experience.

[0053] In conjunction with the first aspect, in some implementations of the first aspect, the control method further includes, after the two right wheels of the electric vehicle have left the ground and abutted against the wall, and before the steering wheel begins to return to the left, controlling the drive system of the electric vehicle to adjust the output torque so that the slip ratio of the two right wheels is less than or equal to a preset slip ratio.

[0054] Slip ratio refers to the degree of relative slippage between the wheel and the ground. During wall climbing, when the two right wheels are in contact with the wall, an excessive slip ratio may lead to insufficient friction between the wheel and the wall, thus affecting the stability and climbing ability of the electric vehicle. The wheel slip ratio is indicated by the vehicle speed and the corresponding resolver sensor. The resolver sensor can accurately detect the position, direction, and speed of the motor rotor, and is responsible for monitoring and extracting the rotational speed of the drive motor. It has a high sampling rate and is directly connected to the motor controller, resulting in a short signal transmission time and higher stability. The rotational speed of the drive motor is obtained through the resolver signal of the resolver sensor. The angular velocity of the wheel is calculated by the rotational speed of the drive motor and the transmission ratio of the electric vehicle. Thus, the wheel slip ratio is obtained by combining the wheel radius and the speed of the electric vehicle. In this application, the slip ratio can be either slip ratio or rotational slip ratio.

[0055] By adjusting the torque output of the drive system in real time, the drive torque of the two right wheels is precisely controlled, thereby adjusting the slip ratio of the two right wheels. When the slip ratio is less than or equal to a preset value, the friction between the wheels and the wall remains within a reasonable range, ensuring that the electric vehicle can stably adhere to the wall surface.

[0056] According to the solution in this application, the slip ratio of the two right wheels is monitored in real time during the wall climbing process, and the drive torque is adjusted according to the actual situation. This ensures that the electric vehicle remains stable under different road and wall conditions, avoids instability or slippage caused by excessive slip ratio, improves the electric vehicle's passability, simplifies the driver's operation process for controlling the electric vehicle to drive close to the wall, reduces driving difficulty, and enhances the driving experience.

[0057] In conjunction with the first aspect, in some implementations of the first aspect, the control method specifically includes controlling the drive system to stop outputting torque after the two right wheels of the electric vehicle have left the ground and abutted against the wall, and when the difference in horizontal height between the two right wheels and the two left wheels increases to a preset height. During the process of controlling the electric vehicle to travel close to the wall, the difference in horizontal height between the two right wheels and the two left wheels is controlled to be less than or equal to the preset height.

[0058] While driving close to a wall, the electric vehicle uses sensors to detect its posture. Climbing walls reduces the width of the road it occupies, but if the height difference between the wheels on both sides is too large, it may tilt excessively and overturn, affecting traffic safety. The electric vehicle controls its drive system and rear-wheel steering system to ensure that the difference in height between the two right wheels and the two left wheels does not exceed a preset height. Once the difference reaches the preset height, the drive system stops outputting torque and the rear-wheel steering system adjusts the rear wheels to return to center. The electric vehicle can also dynamically adjust its suspension system and other related components to ensure that the height difference between the right and left wheels does not exceed a preset height.

[0059] In another embodiment, the electric vehicle detects the tilt of the vehicle body using sensors and controls the drive and braking systems to ensure that the tilt of the vehicle body does not exceed a preset tilt.

[0060] The preset height is a safety threshold determined based on the vehicle's specific parameters and the requirements of narrow road scenarios. By maintaining the height difference within the preset range, the electric vehicle can be kept stable while meeting the requirements for climbing walls and navigating narrow roads. The narrower the road, the greater the difference in horizontal height between the two right wheels and the two left wheels needs to be controlled, thus minimizing the width of the road surface occupied.

[0061] According to the solution in this application, by controlling the height difference between the left and right wheels of the electric vehicle, the risk of rollover caused by excessive tilting during the wall climbing process is reduced, the passability of the electric vehicle is improved, the operation process of the driver controlling the electric vehicle to drive close to the wall is simplified, the driving difficulty is reduced, and the driving experience is improved.

[0062] In conjunction with the first aspect, in some implementations of the first aspect, the control method further includes detecting the passable width of the road surface in front of the electric vehicle while controlling the electric vehicle to travel close to the wall. When the passable width of the road surface is less than or equal to a preset width, the drive system is controlled to stop outputting torque.

[0063] Electric vehicles can detect the passable width of the road surface to determine whether they can drive close to a wall. Passable width refers to the width of the road surface available for the electric vehicle to travel on. Because the maximum tilt of the electric vehicle needs to be limited within a certain range to maintain stability when climbing a wall, the area of ​​road space that the electric vehicle can reduce is limited, and there is a minimum width restriction for its passage. The preset width is the minimum width that the electric vehicle can pass through when driving close to a wall. When the passable width of the road surface is less than or equal to the preset width, the electric vehicle cannot pass smoothly, and the drive system stops outputting torque.

[0064] According to the solution in this application, the passable width of the road surface is detected. When the passable width is small, the drive system is controlled to stop outputting torque to avoid continuing to drive close to the wall and causing driving danger. This improves the passability of electric vehicles, reduces driving difficulty, and enhances the driving experience.

[0065] Secondly, this application provides a control method for an electric vehicle. This method, after the narrow-road passage function of the electric vehicle is activated, automatically controls the rear-wheel steering system and drive system of the electric vehicle to cooperate in order to allow the electric vehicle to pass through a narrow road. The control method includes, after the narrow-road passage function is activated and before the two right wheels contact the wall on the right side of the narrow road, controlling the two front wheels of the electric vehicle to turn to the right and controlling the two rear wheels to turn to the right to a preset angle, and controlling the drive system to drive the wheels of the electric vehicle to rotate. After the first moment and before the second moment when the two right wheels no longer contact the surface of the narrow road, controlling the drive system of the electric vehicle to increase the output torque. After the second moment, controlling the two right wheels to no longer contact the surface of the narrow road and to be in contact with the wall on the right side of the narrow road.

[0066] Passing through narrow roads can be autonomously performed by electric vehicles. This process can be controlled by the electric vehicle's intelligent driving system. The intelligent driving system senses the road conditions and vehicle status and sends control signals to the electric vehicle's rear-wheel steering system and drive system. The rear-wheel steering system and drive system work together to enable the electric vehicle to automatically pass through narrow roads without the need for driver intervention, further reducing the difficulty of operation. Moreover, the intelligent driving system control enables optimized operation, faster response, and higher safety.

[0067] After the driver confirms the activation of the narrow road passage function, the intelligent driving system takes over control of the electric vehicle. It first controls the two front wheels to turn right and then the two rear wheels to turn right to a preset angle, and controls the drive system to output torque, thus driving the electric vehicle along the wheel rotation angle. The electric vehicle gradually approaches the edge of the narrow road, and at the first moment, the two right wheels contact the wall on the right side of the narrow road. At this initial moment, with the two right wheels against the wall, the intelligent driving system controls the drive system to increase the output torque, thereby increasing the contact area and pressure between the two right wheels and the wall, and thus gradually increasing the friction between the two right wheels and the wall.

[0068] At the second moment, the friction between the two right wheels and the wall is large enough that the two right wheels can rotate upward along the wall by relying on the friction with the wall. The two right wheels leave the surface of the narrow road and no longer contact the surface. As a result, the area occupied by the electric vehicle in the narrow road is reduced, and the electric vehicle can pass through the narrow road.

[0069] It should be understood that when an electric vehicle controls narrow-road passage in intelligent assisted driving mode or intelligent autonomous driving mode, the intelligent driving system controls the drive system and rear-wheel steering system without driver intervention. If the driver intervenes, the driver's signals should take priority. When the driver's active operation is detected, such as turning the steering wheel, pressing the accelerator pedal, or pressing the brake pedal, the electric vehicle determines that the driver has intervened, stops the automatic narrow-road passage control, and responds to the driver's operation to resume control.

[0070] It should be understood that the relevant operational descriptions of the control method executed by the intelligent driving system can be found in the descriptions in the first aspect and its various implementations.

[0071] According to the solution in this application, the electric vehicle intelligent driving system controls the coordination of the rear wheel steering and the drive system to automatically achieve actions such as hugging the wall, climbing the wall, and driving through narrow roads. This greatly simplifies the driver's operation difficulty in narrow road passing scenarios, improves the electric vehicle's ability to pass and its stability in narrow road scenarios, and significantly enhances the driver's satisfaction and experience when using the vehicle.

[0072] In conjunction with the second aspect, in some implementations of the second aspect, the control method further includes controlling the drive system to adjust the output torque so that the slip ratio of the two right wheels is less than or equal to the preset slip ratio after the second moment and before the third moment when the horizontal height of the two right wheels reaches the preset value.

[0073] The intelligent driving system uses a perception system to detect information such as the passable width of the narrow road, the angle between the narrow road and the wall, and the height of the wall. This allows it to determine the required horizontal height for the two right wheels to climb the wall. When the horizontal height of the two right wheels reaches a preset value, the electric vehicle can pass through the narrow road. Between the second moment and the third moment when the horizontal height of the two right wheels reaches the preset value, the drive system continuously monitors the slip ratio of the two right wheels and adjusts the output torque to ensure that the slip ratio of the two right wheels is less than or equal to the preset slip ratio. This maintains the friction between the wheels and the wall within a reasonable range, ensuring that the vehicle can stably adhere to the wall surface.

[0074] According to the solution in this application, the slip ratio of the two right wheels is monitored in real time during wall climbing, and the drive torque is adjusted according to the actual situation. This ensures that the electric vehicle remains stable under different road and wall conditions, avoiding instability or slippage caused by excessive slip ratio. It improves the electric vehicle's ability to pass through narrow road scenarios, simplifies the driver's operation in narrow road passing scenarios, reduces driving difficulty, and enhances the driving experience.

[0075] In conjunction with the second aspect, in some implementations of the second aspect, the control method further includes, after the third moment and before the fourth moment when the steering wheel of the electric vehicle turns again, controlling the steering wheel to return to center to control the front wheel and the right wheel to return to center, and driving the system to drive the wheels to rotate so that the two right wheels rotate in contact with the wall.

[0076] In conjunction with the second aspect, in some implementations of the second aspect, the control method further includes, after the fourth moment and before the fifth moment, when the two right wheels and the road surface of the narrow road re-contact and the two right wheels are no longer in contact with the wall on the right side of the narrow road, controlling the steering wheel to turn to the right to control the front wheels to turn to the right and controlling the rear wheels to turn to the right to a preset angle, and controlling the drive system to adjust the output torque to drive the electric vehicle to reverse.

[0077] At the fifth moment, the four wheels of the electric vehicle returned to the surface of the narrow road, completing the entire narrow road passage process, and the electric vehicle exited the narrow road passage control.

[0078] In conjunction with the second aspect, in some implementations of the second aspect, the control method further includes, after the fourth moment and before the fifth moment, when the two right wheels and the road surface of the narrow road re-contact and the two right wheels are no longer in contact with the wall on the right side of the narrow road, controlling the steering wheel to turn to the left to control the front wheels to turn to the left and controlling the rear wheels to turn to the left to a preset angle, and controlling the drive system to output torque to drive the electric vehicle to continue driving.

[0079] In conjunction with the second aspect, in some implementations of the second aspect, the control method further includes, after the narrow road passage function is activated but before the first moment, controlling the electric vehicle's suspension system to increase damping and adjust the height of the right side of the electric vehicle to be greater than the height of the left side. After the second moment but before the third moment, controlling the suspension system to gradually decrease the height of the right side of the vehicle and gradually increase the height of the left side. After the fourth moment, controlling the suspension system to adjust the height of the right side of the vehicle to be equal to the height of the left side.

[0080] In conjunction with the second aspect, in some implementations of the second aspect, the control method further includes detecting the passable width of the narrow road in front of the electric vehicle, and prompting the driver to activate or deactivate the narrow road passage function based on the passable width of the narrow road. When the narrow road passage function is not activated, if the passable width of the narrow road is greater than a preset width but less than the width of the electric vehicle, the driver is prompted to activate the narrow road passage function. If the passable width of the narrow road is less than or equal to the preset width, the driver is prompted to deactivate or the narrow road passage function cannot be activated.

[0081] When the intelligent driving system detects a narrow road ahead, it needs to determine whether it's suitable to activate the narrow road passage function based on the passable width of the narrow road. Passable width refers to the width of the road surface available for the electric vehicle to travel on. If the passable width of the narrow road is greater than the preset width but less than the width of the electric vehicle, it means the electric vehicle cannot normally pass through the narrow road. The preset width is the minimum width the electric vehicle can pass through when the narrow road passage function is activated. Because the maximum tilt of the electric vehicle needs to be limited within a certain range to maintain stability when climbing walls or passing through narrow roads, the area occupied by the electric vehicle in the narrow road is limited, resulting in a minimum passable width. When the passable width of the narrow road is less than or equal to the preset width, the electric vehicle cannot pass through the narrow road smoothly even if the narrow road passage function is activated, and the driver needs to be prompted to deactivate or disable the narrow road passage function.

[0082] According to the solution in this application, the intelligent driving system detects the passable width of narrow roads and prompts the driver whether the narrow road passage function can be used based on the passable width, avoiding accidental activation that could lead to driving danger, improving the ability of electric vehicles to pass through narrow road scenarios, reducing driving difficulty, and enhancing the driving experience.

[0083] Thirdly, this application provides a vehicle controller for electric vehicles, which is used to implement the control methods described in the first aspect and its various implementations or the second aspect and its various implementations.

[0084] The vehicle controller in this application may be a motor controller for an electric vehicle, a vehicle controller, an intelligent driving controller, or a separately configured controller with control capabilities.

[0085] The intelligent driving controller in this application is a domain controller used to realize functions such as perception, localization, path planning, and decision control. When the electric vehicle is in intelligent driving mode, the intelligent driving controller performs intelligent active driving or assists the user in driving. The intelligent driving controller receives perception data signals sent by the electric vehicle's perception components, such as radar and cameras. The intelligent driving controller fuses the information perceived by various sensors and obtains the electric vehicle's driving status and lane information based on the perception data signals. By analyzing signals such as distance, speed, and acceleration, it obtains target acceleration and target speed, etc. Based on the fused information, it makes driving decisions / planning, issues operation commands to the vehicle controller, and the vehicle controller sends an intelligent driving torque signal to the motor controller, thereby outputting the torque value indicated by the intelligent driving torque signal to complete intelligent driving.

[0086] Fourthly, this application provides an electric vehicle including a drive system, an accelerator pedal, a steering wheel, and a vehicle controller as described in the third aspect, wherein the accelerator pedal is used to instruct the drive system to output torque to the wheels of the electric vehicle, and the steering wheel is used to instruct the steering angle of the wheels of the electric vehicle.

[0087] Other beneficial effects can be found in the description of the first aspect, and will not be repeated here. Attached Figure Description

[0088] Figure 1 This is a schematic diagram of an electric vehicle provided in an embodiment of this application; Figure 2 This is a schematic diagram of the architecture of an electric vehicle provided in an embodiment of this application; Figure 3 This is a schematic diagram of the rear wheel steering of an electric vehicle provided in an embodiment of this application; Figure 4 This is a schematic diagram of the driving scenario of an electric vehicle provided in an embodiment of this application; Figure 5 This is a schematic diagram illustrating the activation method of the narrow road passage function for electric vehicles provided in this application embodiment; Figure 6 This is a top view of the process of the rear wheels of an electric vehicle turning toward a wall, as provided in the embodiments of this application; Figure 7 This is a rear view of the process of one side wheel of an electric vehicle climbing a wall, as provided in an embodiment of this application. Figure 8 This is a left rear view of an electric vehicle's wheel climbing over a wall and traversing a narrow road, as provided in an embodiment of this application. Figure 9 This is a rear view of the suspension control of an electric vehicle during narrow road passage, as provided in an embodiment of this application. Figure 10 This is a schematic diagram of the process of an electric vehicle passing through a narrow road, as provided in an embodiment of this application. Detailed Implementation

[0089] The technical solutions in this application will now be described in conjunction with the accompanying drawings. The detailed descriptions and drawings of the following embodiments are used to exemplarily illustrate the principles of this application, but should not be used to limit the scope of this application; that is, this application is not limited to the described embodiments.

[0090] Figure 1 and Figure 2 This is a schematic diagram of the architecture of the electric vehicle 10 provided in the embodiments of this application.

[0091] like Figure 1 As shown, the electric vehicle 10 includes a vehicle controller 20, a drive system 50, a braking system 60, an intelligent driving system 70, a power battery (not shown), and multiple wheels. The drive system 50 includes a drive motor 30 and a motor controller 40. The motor controller 40 outputs current to the drive motor 30 to control the drive motor 30 to output torque to drive the wheels of the electric vehicle 10. The intelligent driving system 70 includes an intelligent driving controller, which plans a driving path based on environmental information detected by the sensors of the electric vehicle 10 and the driving information of the electric vehicle 10.

[0092] The vehicle controller provided in this application may be the motor controller 40 of the electric vehicle 10, or the vehicle controller 20, or the intelligent driving system 70, or a separately configured controller with control capabilities.

[0093] The electric vehicle 10 can be a rear-wheel drive vehicle, with the two rear wheels driven by a drive motor 30. Alternatively, the electric vehicle 10 can have a distributed four-motor drive architecture, with the drive motors positioned beside the driving wheels and controlled by individual motor controllers 40. The electric vehicle 10 can also have a centralized drive motor architecture, with the drive motors for driving the two front wheels or the two rear wheels grouped together. There can be one or more motor controllers 40. The motor controller 40 can correspond one-to-one with the drive motors 30, or one motor controller 40 can correspond to multiple drive motors 30. The motor controller 40 is used to control the output torque of one or more drive motors 30 to drive the electric vehicle 10.

[0094] In one embodiment, such as Figure 2 As shown in (a), the electric vehicle 10 can be a distributed four-motor drive architecture, with the drive motors positioned beside the driving wheels and controlled by individual motor controllers. The electric vehicle 10 can also be as follows: Figure 2The centralized four-drive motor drive architecture shown in (b) has two drive motors for driving the two front wheels or the two rear wheels set together.

[0095] For example, the electric vehicle 10 includes four motor controllers: motor controller 41, motor controller 42, motor controller 43, and motor controller 44. The four motors include drive motor 31, drive motor 32, drive motor 33, and drive motor 34. Motor controller 41 controls drive motor 31 to drive wheel 51, motor controller 42 controls drive motor 32 to drive wheel 52, motor controller 43 controls drive motor 33 to drive wheel 53, and motor controller 44 controls drive motor 34 to drive wheel 54.

[0096] In one embodiment, the electric vehicle 10 may also be as follows: Figure 2 The centralized drive motor architecture shown in (c) uses one drive motor to drive the two front wheels of the electric vehicle 10, and two drive motors to drive the two rear wheels of the electric vehicle 10 respectively.

[0097] In one embodiment, the various architectures mentioned above can also be combined, for example, the front drive adopts a distributed drive motor architecture and the rear drive adopts a centralized drive motor architecture.

[0098] The vehicle controller provided in this application can be any one of multiple motor controllers.

[0099] The electric vehicle 10 also includes an accelerator pedal, a brake pedal, a steering system, and a steering wheel. The accelerator pedal is used to indicate the torque output to the wheels of the electric vehicle 10. The brake pedal is used to indicate the braking force output to the wheels of the electric vehicle 10, the steering wheel angle is used to indicate the steering angle of the wheels, and the steering system is used to control the steering angle of the wheels of the electric vehicle 10.

[0100] In one embodiment, each motor controller 40 is connected to a resolver sensor via a signal interface. The resolver sensor is used to detect the rotational speed of the drive motor 30 controlled by the motor controller 40, and the motor controller 40 is used to receive signals from the resolver sensor.

[0101] The resolver sensor can accurately detect the position, direction and speed of the motor rotor, and is responsible for monitoring and extracting the rotational speed of the drive motor. It has a high sampling rate and is directly connected to the motor controller 40, resulting in short signal transmission time and higher stability.

[0102] In one embodiment, the motor controller 40 also acquires vehicle signals from the vehicle controller 20 or other sensors of the electric vehicle 10 via a signal interface. The vehicle signals are used to indicate the vehicle speed, yaw rate, and center of gravity sideslip angle of the electric vehicle 10.

[0103] In one embodiment, the motor controller 40 can connect to the vehicle controller 20, the intelligent driving system 70, and the steering system via a controller area network (CAN) bus, a local interconnect network (LIN) bus, a high-speed fault-tolerant network protocol (FlexRay), or other types of connection methods, and exchange signals.

[0104] The steering system includes the rear-wheel steering system. The rear-wheel steering system of electric vehicles is used to change the rotation angle and orientation of the two rear wheels, thereby effectively adjusting the vehicle's steering and handling characteristics through different steering methods.

[0105] like Figure 3 As shown, under certain operating conditions, the chassis domain controller calculates the rear wheel steering angle command through its internal algorithm control strategy and sends the command to the CAN network. The rear wheel steering system, under certain conditions, receives the rear wheel steering angle command transmitted from the vehicle's CAN network. Under the control of the rear wheel steering system, the rear wheels follow the steering angle command within a certain angle range, performing left or right steering actions. For existing electric vehicles, at lower speeds, the rear wheels steer in the opposite direction to the front wheels, reducing the turning radius and improving overall vehicle handling and agility. At higher speeds, the rear wheels steer in the same direction as the front wheels, effectively reducing the yaw moment generated during steering operations and enhancing vehicle stability.

[0106] For example, such as Figure 3 As shown in (a), when the vehicle speed is greater than 60 kph, the rear wheels follow the front wheels in steering in the same direction. By increasing the steering angle of the rear wheels, the yaw rate generated by the front wheels during steering is offset, thereby reducing the risk of skidding and rollover. This makes the vehicle more stable at high speeds, especially in emergency avoidance or sudden lane changes, providing better handling and safety.

[0107] For example, such as Figure 3 As shown in (b), when the vehicle speed is less than or equal to 60 kph, the rear wheels follow the front wheels in the opposite direction to reduce the overall turning radius of the vehicle and improve its agility and maneuverability at low speeds. Applying this technology to operations in confined spaces, such as parking lots or crowded streets, allows the vehicle to complete turns and U-turns more easily.

[0108] However, as Figure 4As shown, for some special scenarios, such as passing on narrow roads in mountainous areas or avoiding narrow roads in old urban areas, it is necessary to reduce the width of the road occupied by electric vehicles in order to pass smoothly. At this time, the steering direction of the rear wheels is opposite to that of the front wheels at low speeds, which cannot reduce the width of the road occupied and cannot meet the passage requirements in special scenarios.

[0109] To address the aforementioned issues, this application provides a control method, a vehicle controller, and an electric vehicle. By using a rear-wheel steering system, the rear wheels can be steered in the same direction as the front wheels, allowing both right wheels to contact the wall surface, increasing friction, and enabling one side to smoothly climb the wall. This reduces the width of the road surface occupied by the electric vehicle, enabling it to smoothly complete operations such as passing on narrow roads, simplifying the operation of driving close to the wall, and improving the ability of the electric vehicle to pass close to the wall in special scenarios.

[0110] The following is combined Figures 5-10 The control method provided in the embodiments of this application is described below. This control method is used to control the rear wheel steering system and drive system 50 of the electric vehicle 10 to cooperate with each other so that the electric vehicle 10 drives close to the wall after the narrow road passage function of the electric vehicle 10 is activated. Figure 6 This is a top view of the electric vehicle 10 as its rear wheels steer towards the wall. Figure 7 This is a rear view of the electric vehicle 10 as it climbs the wall on one side. Figure 8 This is a left rear view of an electric vehicle 10 traveling along a narrow road with one of its wheels close to the wall. Figure 9 This is a rear view of the suspension control during the process of an electric vehicle 10 driving close to a wall. Figure 10 This is a diagram illustrating the process of an electric vehicle traveling close to a wall.

[0111] like Figure 6 and Figure 10 As shown, the control method includes, while the electric vehicle 10 is traveling at a speed lower than a preset speed, after the steering wheel of the electric vehicle 10 begins to turn to the right, controlling the rear wheel steering system to drive the two rear wheels to turn to the right along with the two front wheels. After the two rear wheels have turned to the right along with the two front wheels, and after the accelerator pedal opening of the electric vehicle 10 increases, controlling the drive system 50 to output a first positive torque to drive the electric vehicle 10 to move laterally to the right. After the electric vehicle 10 has moved laterally to the right until the distance between it and the wall on the right side of the road is less than a preset distance, controlling the drive system 50 to output a second positive torque greater than the first positive torque to cause the two right wheels of the electric vehicle 10 to leave the ground and abut against the wall.

[0112] In some special scenarios, after the narrow road passage function is activated, the electric vehicle 10 can use the wall beside the road to pass through narrow roads. The electric vehicle 10 reduces the width of the road it occupies by climbing the wall, thus enabling it to pass through the narrow road. When the narrow road passage function is activated, the control system of the rear wheel steering system and the drive system 50 work together to make the electric vehicle 10 drive close to the wall to pass through the narrow road.

[0113] It should be understood that the narrow roads in this application include narrow driving surfaces with walls on both sides, and narrow driving surfaces with a wall on one side that prevents driving on the other side, such as mountain roads and narrow alleys in urban areas. To enable climbing over walls and reduce the width of the road surface occupied, a climbable wall is required on one side of the narrow road. The walls in this application include building walls, mountain slopes, roadside retaining walls, protective slopes, curbs, and other sloping or vertical surfaces. These walls can be man-made or naturally formed. The wall forms a certain angle with the road surface and has a certain height relative to the road surface. Under normal driving conditions, vehicles only travel on the road surface and will not drive onto the wall.

[0114] In one implementation, the control method is used to control the rear-wheel steering system and drive system 50 of the electric vehicle 10 to cooperate in order to enable the electric vehicle 10 to drive close to the wall after the narrow-road passage function of the electric vehicle 10 is activated. The electric vehicle 10 is equipped with a narrow-road passage function, which can assist the electric vehicle 10 in passing through narrow roads by adjusting the control method to utilize the aforementioned wall-hugging driving function.

[0115] When the narrow-road passage function of the electric vehicle 10 is not activated, if the speed of the electric vehicle 10 is less than a preset speed, the direction of rotation of the rear wheels is controlled to be opposite to the direction of rotation of the steering wheel. When the narrow-road passage function is activated, if the speed of the electric vehicle 10 is less than a preset speed, the direction of rotation of the rear wheels is controlled to be the same as the direction of rotation of the steering wheel.

[0116] In one embodiment, such as Figure 5 As shown, the electric vehicle 10 is used to control the electric vehicle 10 to activate the narrow road passage function by touching the central control screen of the electric vehicle 10 or activating the narrow road passage function button.

[0117] It should be understood that the narrow-road passage function of electric vehicle 10 usually requires manual activation by the driver. Because electric vehicle 10 is in an unconventional driving state when using the narrow-road passage function to pass through narrow roads, the driver needs to confirm in advance whether narrow-road passage is permissible and allow the driver and passengers to prepare in advance to avoid panic and misoperation. When electric vehicle 10 is in intelligent driving mode, if the intelligent driving system detects a narrow road passage scenario ahead, it also needs to prompt the driver whether to activate the narrow-road passage function. Only after the driver confirms activation can intelligent driving continue or the driver take over.

[0118] In one possible embodiment, the electric vehicle 10 includes a narrow-road passage function button. When the narrow-road passage function button is off, the electric vehicle 10 controls the rear wheels to rotate in the opposite direction to the steering wheel when the vehicle speed is less than a preset speed. When the narrow-road passage function button is on, the electric vehicle 10 activates the narrow-road passage function, and when the vehicle speed is less than the preset speed, the electric vehicle 10 controls the rear wheels to rotate in the same direction as the steering wheel.

[0119] The electric vehicle 10 is equipped with a narrow-road passage function button for driver operation. Exemplarily, the narrow-road passage function button is a physical button, which the driver presses to activate the narrow-road passage function of the electric vehicle 10. Alternatively, the narrow-road passage function button can be a virtual button on the central control screen, which the driver activates by selecting the narrow-road passage function mode. Furthermore, the narrow-road passage function button can also be indirectly configured, for example, integrated into the rear-wheel steering button or other function buttons. This application does not limit the method or form of the narrow-road passage function button.

[0120] While the electric vehicle 10 is traveling at a speed lower than the preset speed, after the steering wheel of the electric vehicle 10 begins to turn to the right, both front wheels and both rear wheels of the electric vehicle 10 are first controlled to turn to the right. When passing through narrow roads or driving close to walls, the speed of the electric vehicle 10 should not be too high; it should be passed through at a low speed as much as possible to avoid scrapes and collisions. When the electric vehicle 10 is traveling at a speed lower than the preset speed, after the steering wheel is turned to the right, the front wheels turn to the right, and the rear wheels follow the front wheels to turn to the right. At this time, the rear wheel steering system controls the front and rear wheels to turn in the same direction. In narrow road scenarios, the electric vehicle 10 needs to stay as close to the wall as possible to reduce the width of the road it occupies. By turning the front and rear wheels to the right simultaneously, the electric vehicle 10 can steer more precisely to the right, providing the initial conditions for subsequent wall-climbing maneuvers.

[0121] After the accelerator pedal of electric vehicle 10 is opened wider, the drive system 50 is then controlled to drive the wheels of electric vehicle 10 to rotate. When the driver depresses the accelerator pedal, the drive system 50 outputs a first positive torque to drive the wheels to rotate, causing electric vehicle 10 to move laterally to the right. It should be understood that moving laterally to the right can mean that electric vehicle 10 moves diagonally to the right front. In this state, the orientation of electric vehicle 10 does not change, and the vehicle body does not rotate. After both front wheels and both rear wheels turn to the right, electric vehicle 10 moves to the right, thus moving parallel to the wall and approaching the wall on the right side of the road. After electric vehicle 10 moves laterally to the right until the distance to the wall on the right side of the road is less than a preset distance, the vehicle body of electric vehicle 10 is sufficiently close to the wall. Since both front and rear wheels turn to the right, both right wheels are in contact with the wall, resulting in a large contact area and balanced forces. If the front and rear wheels rotate in opposite directions, only one of the front or rear wheels of the electric vehicle 10 will contact the wall when turning. This results in a small contact area and an imbalance of forces, making it difficult for the electric vehicle 10 to climb the wall. After both right wheels are in contact with the wall, the drive system 50 outputs a second positive torque greater than the first positive torque. This causes the right wheels of the electric vehicle 10 to gradually move upwards along the wall, so that the two right wheels no longer contact the road surface and instead adhere to the right side of the wall. The two right wheels then detach from the road surface and adhere to the wall. Because the right wheels need to be driven to gradually move upwards along the wall, the second positive torque output by the drive system 50 must be greater than the torque used when driving on a flat road. Through the coordinated steering of the front and rear wheels and the drive of the drive system 50, the two right wheels of the electric vehicle 10 can stably adhere to the wall surface, increasing the contact area and friction between the right wheels and the wall, thus helping the vehicle to successfully complete the wall-climbing maneuver. The drive system 50 drives the wheels to rotate along the wall so that the two right wheels of the electric vehicle 10 travel to the wall on the right side of the road, so that the horizontal height of the two right wheels is higher than that of the two left wheels. Using the force of the wheel rotation, the right side of the electric vehicle 10 climbs onto the wall, thereby reducing the width of the road occupied by the electric vehicle 10.

[0122] It should be understood that this application describes the situation as vehicles all driving on the right. Therefore, when electric vehicle 10 is driving close to a wall to pass through narrow roads or meet oncoming traffic, the right wheel of electric vehicle 10 is usually driven onto the wall on the right side of the road. For roads where vehicles all drive on the left or where there is only a usable wall on the left side of the road, both the front and rear wheels of electric vehicle 10 turn to the left, causing the left wheel of electric vehicle 10 to drive onto the wall on the left side of the road. The actions are modified accordingly, and the direction of rotation is reversed. This will not be described in detail here.

[0123] According to the solution of this application, through the coordination of the rear wheels and the front wheels turning in the same direction and the drive system 50, the electric vehicle 10 can more easily fit against the wall and complete the wall climbing action, thereby smoothly passing through narrow roads. This simplifies the driver's operation process in narrow road meeting scenarios, reduces driving difficulty, improves the vehicle's ability to pass in narrow road scenarios, enhances the driver's control and operation convenience, and significantly improves the driver's satisfaction and experience when using the vehicle.

[0124] In one embodiment, the control method specifically includes controlling the steering angles of the front and rear wheels to remain the same after the steering wheel begins to turn right and before the rightward steering angle of the rear wheels increases to a preset steering angle. After the rightward steering angle of the rear wheels increases to the preset steering angle, while the steering wheel continues to turn right, controlling the rightward steering angle of the front wheels to be greater than the rightward steering angle of the rear wheels.

[0125] When the rear wheel's rightward turning angle is less than the preset turning angle, the turning angles of the front and rear wheels are controlled to be equal and increase as the steering wheel angle increases. When the electric vehicle 10 is traveling at high speed, the angle of the rear wheels turning in the same direction needs to be strictly limited to avoid affecting the stability of the electric vehicle 10. After the steering wheel begins to turn to the right, when the electric vehicle 10 is traveling at low speed, the front and rear wheels turn in the same direction and the turning angles remain the same. The limitation on the steering angle of the rear wheels is less, and a larger angle of rear wheel rotation will not affect the stability of the electric vehicle 10. When the rear wheel's rightward turning angle is greater than the preset turning angle, the front wheel's turning angle is controlled to be greater than the rear wheel's turning angle. As the steering wheel angle increases to the right, the front wheel's rightward turning angle is controlled to increase, and the rear wheel's rightward turning angle is controlled to increase to the preset turning angle, which is less than the maximum turning angle of the rear wheels.

[0126] The preset steering angle is the rear wheel steering angle that facilitates the electric vehicle 10's ability to climb walls, or the allowable rotation angle of the electric vehicle 10's rear wheels when traveling at low speeds. Once the rear wheel steering angle reaches the preset angle, it no longer increases with the steering wheel's rotation angle, while the front wheel steering angle continues to increase with the steering wheel's rotation angle until it reaches the maximum rotation angle of the front wheels.

[0127] In one embodiment, the electric vehicle 10 reminds the driver to turn the steering wheel to a suitable angle via voice or in-vehicle screen. At this angle, the two rear wheels turn to the right to a preset angle, which makes it easier to climb the wall.

[0128] It should be understood that the preset turning angle is pre-calibrated based on actual vehicle experiments and / or model calculations, or it can be pre-set by comprehensively considering the needs and performance of the entire vehicle.

[0129] In one embodiment, the control method specifically includes increasing the rightward turning angle of the rear wheels to a first angle when the angle between the road surface and the wall is a first slope. When the angle between the road surface and the wall is a second slope greater than the first slope, increasing the rightward turning angle of the rear wheels to a second angle less than the first angle.

[0130] The electric vehicle 10 uses a perception system to detect its surrounding environment and operational status. This perception system includes sensors such as cameras, lidar, and millimeter-wave radar to perceive the surrounding environment and collect and process environmental and in-vehicle information, primarily involving technologies such as road boundary monitoring, vehicle detection, and pedestrian detection. Based on the acquired perception data, the electric vehicle 10 detects information about itself and obstacles and plans its driving path. The perception data includes relative distance, relative speed, relative acceleration, and lane information. The electric vehicle 10 can also detect the slope of the right-hand wall of the road surface, i.e., the angle between the road surface and the wall, using sensors such as cameras and radar. Typically, the angle between the road surface and the wall is between 90 and 180 degrees.

[0131] To control the electric vehicle 10 in its wall-climbing maneuver, it's crucial that both rear wheels of the electric vehicle 10 make full contact with the wall and generate sufficient friction. When the angle between the road surface and the wall is small, the electric vehicle 10 requires a larger rear wheel steer angle to ensure full wheel contact with the wall, increasing friction and aiding in the climb. A larger steer angle helps the electric vehicle 10 maintain a stable contact with the wall in narrow spaces. As the angle between the road surface and the wall increases, the electric vehicle 10's dependence on the wall decreases, requiring a smaller rear wheel steer angle. A smaller steer angle reduces the electric vehicle 10's excessive reliance on the wall while ensuring smooth vehicle movement, avoiding the risk of instability or rollover due to excessive steer angles.

[0132] In one embodiment, the control method further includes controlling the drive system 50 of the electric vehicle 10 to adjust the output torque so that the slip ratio of the two right wheels is less than or equal to a preset slip ratio after the two right wheels of the electric vehicle 10 have left the ground and abutted against the wall and before the steering wheel begins to return to the left.

[0133] Slip ratio refers to the degree of relative slippage between a wheel and the ground. During wall climbing, when the two right wheels are in contact with the wall, an excessive slip ratio may lead to insufficient friction between the wheels and the wall, thus affecting the stability and wall climbing ability of the electric vehicle 10. The wheel slip ratio is indicated by the vehicle speed and the resolver sensor corresponding to that wheel. The resolver sensor can accurately detect the position, direction, and speed of the motor rotor, is responsible for monitoring and extracting the rotational speed of the drive motor, has a high sampling rate, and is directly connected to the motor controller, resulting in a short signal transmission time and higher stability. The rotational speed of the drive motor is obtained through the resolver signal of the resolver sensor. The angular velocity of the wheel is calculated by the rotational speed of the drive motor and the transmission ratio of the electric vehicle 10. Thus, the wheel slip ratio is obtained by combining the wheel radius and the speed of the electric vehicle 10. In this application, the slip ratio can be either slip ratio or rotational slip ratio.

[0134] By adjusting the torque output of the drive system 50 in real time, the drive torque of the two right wheels is precisely controlled, thereby adjusting the slip ratio of the two right wheels. When the slip ratio is less than or equal to a preset value, the friction between the wheels and the wall remains within a reasonable range, ensuring that the electric vehicle 10 can stably adhere to the wall surface.

[0135] In one embodiment, the control method further includes, after the two right wheels of the electric vehicle 10 have left the ground and are in contact with the wall, controlling the drive system 50 to stop outputting torque as the steering wheel begins to turn to the left. After the steering wheel turns to the left, the drive system 50 outputs a third positive torque, less than the second positive torque, to drive the electric vehicle 10 to travel along the wall.

[0136] Guided by the right-hand wheels turning to the right, electric vehicle 10 will climb the wall. As both right wheels press against the wall and ascend, they leave the road surface, while the two left wheels make contact with the road, completing the wall-climbing maneuver and achieving wall-hugging travel. At this point, the area occupied by electric vehicle 10 on the road surface is reduced. For different scenarios, electric vehicle 10 can subsequently employ different strategies for traversing the terrain.

[0137] In one embodiment, the electric vehicle 10 needs to actively traverse the narrow road. After completing the wall-climbing maneuver, the electric vehicle 10 needs to maintain its wall-climbing posture and continue driving along the wall to pass through the narrow road. Once the electric vehicle 10 has completed the wall-climbing maneuver and its two right wheels are in contact with the wall on the right side of the narrow road, the steering wheel is turned to the left to straighten it. This causes the two right wheels of the electric vehicle 10 to no longer face upwards towards the wall, and the horizontal height no longer increases; instead, they face forward along the wall. The drive system 50 outputs a third positive torque, less than the second positive torque, to drive the electric vehicle 10 to travel along the wall, maintaining the posture of its two left wheels on the road surface and its two right wheels on the wall.

[0138] In one implementation, the control method specifically includes controlling the braking system 60 to output braking force to all four wheels after the steering wheel is returned to the left.

[0139] In another embodiment, the electric vehicle 10 does not need to actively traverse the narrow road. For example, in a scenario where oncoming traffic meets on a narrow road, after completing the wall-climbing maneuver, the electric vehicle 10 can choose to remain stationary while climbing, waiting for the oncoming vehicle to pass before proceeding. Once the electric vehicle 10 has completed the wall-climbing maneuver and its two right wheels are in contact with the right side of the wall, the steering wheel is turned to the left to straighten it. This prevents the two right wheels of the electric vehicle 10 from pointing upwards towards the wall, thus halting its horizontal movement and instead pointing forward along the wall. After the steering wheel is turned to the left, the drive system 50 stops outputting torque, and the electric vehicle 10 remains stationary or brakes, waiting for the oncoming vehicle to pass before descending from the wall. Straightening the wheels improves the stability of the electric vehicle 10 while climbing the wall and prepares it for subsequent maneuvers.

[0140] In one embodiment, the control method specifically includes controlling the drive system 50 to stop outputting torque after the two right wheels of the electric vehicle 10 have left the ground and abutted against the wall, and when the difference between the horizontal height of the two right wheels and the horizontal height of the two left wheels increases to a preset height. During the process of controlling the electric vehicle 10 to travel close to the wall, the difference between the horizontal height of the two right wheels and the horizontal height of the two left wheels is controlled to be less than or equal to the preset height.

[0141] During wall-climbing maneuvers, the electric vehicle 10 uses sensors to detect its vehicle posture. While climbing walls reduces road width occupied, excessive height difference between the wheels on both sides could cause the vehicle to tilt excessively and overturn, compromising traffic safety. The electric vehicle 10 controls the drive system 50 and rear-wheel steering system to ensure the height difference between the two right wheels and the two left wheels does not exceed a preset height. Once this difference is reached, the drive system 50 stops outputting torque and the rear-wheel steering system adjusts the rear wheels to return to center. The electric vehicle 10 can also dynamically adjust the suspension system and other related components to ensure the height difference between the right and left wheels does not exceed a preset height.

[0142] In another embodiment, the electric vehicle 10 detects the tilt of the vehicle body using sensors and controls the drive system 50 and braking system 60 to ensure that the tilt of the vehicle body does not exceed a preset tilt.

[0143] The preset height is a safety threshold determined based on the vehicle's specific parameters and the requirements of narrow road scenarios. By maintaining the height difference within the preset range, the electric vehicle 10 can be kept stable while meeting the requirements for climbing walls and traversing narrow roads. The narrower the road, the greater the difference between the horizontal heights of the two right wheels and the two left wheels needs to be controlled by the electric vehicle 10, thus minimizing the width of the road it occupies.

[0144] In one embodiment, the control method further includes detecting the passable width of the road surface in front of the electric vehicle 10 while controlling the electric vehicle 10 to drive close to the wall. When the passable width of the road surface is less than or equal to a preset width, the drive system 50 is controlled to stop outputting torque.

[0145] The electric vehicle 10 can detect the passable width of the road surface to determine whether it can travel close to a wall. The passable width refers to the width of the road surface available for the electric vehicle 10 to travel on. Because the maximum tilt of the electric vehicle 10 needs to be limited within a certain range to maintain stability when climbing a wall, the area of ​​road surface that the electric vehicle 10 can reduce is limited, and there is a minimum width constraint. The preset width is the minimum width that the electric vehicle 10 can pass when traveling close to a wall. When the passable width of the road surface is less than or equal to the preset width, the electric vehicle 10 cannot pass smoothly, and the drive system 50 stops outputting torque.

[0146] In one embodiment, the control method further includes controlling the drive system 50 to output reverse torque to drive the electric vehicle 10 backward and reduce the ground clearance of the two right wheels after the electric vehicle 10 has traveled a distance greater than a preset distance along the wall and the steering wheel has been turned to the right to a angle greater than a preset angle.

[0147] After the electric vehicle 10 has traveled a distance closer to the wall than a preset distance and the steering wheel has been turned to the right to a angle greater than a preset angle, the electric vehicle 10 has completed the wall-climbing maneuver. For example, after the electric vehicle 10 has passed through the narrow road, the electric vehicle 10 is controlled to return to the road surface. After the steering wheel is turned to the right to a angle greater than a preset angle, the front wheels and both rear wheels are controlled to turn to the right, achieving the same state as when climbing the wall. The drive system 50 is then controlled to output reverse torque, causing the wheels to rotate in the opposite direction. The electric vehicle 10 reverses, thereby causing the two right wheels to disengage from the wall and return to the road surface.

[0148] In one embodiment, the control method further includes controlling the drive system 50 to stop outputting the reverse torque after the drive system 50 outputs reverse torque to drive the electric vehicle 10 backward and the ground clearance of the two right wheels decreases until the two rear wheels re-contact the road surface.

[0149] After the electric vehicle 10 reverses and the two right wheels are removed from the state of being in contact with the wall and returned to the road surface, the control drive system 50 stops outputting reverse torque to prevent the electric vehicle 10 from continuing to reverse.

[0150] In one embodiment, the control method further includes, after controlling the electric vehicle 10 to travel a distance closer to the wall than a preset distance and after the steering wheel is turned to the left to a angle greater than a preset angle, the braking drive system 50 outputs positive torque to drive the electric vehicle 10 forward and the ground clearance of the two right wheels is reduced.

[0151] After the electric vehicle 10 has traveled a distance closer to the wall than a preset distance and the steering wheel has been turned to the right to a angle greater than a preset angle, the electric vehicle 10 has completed the wall-climbing maneuver. For example, after the electric vehicle 10 has passed through a narrow road, the electric vehicle 10 is controlled to return to the road surface. After the steering wheel is turned to the left to a angle greater than a preset angle, the front wheels and both rear wheels are controlled to turn to the left, and the drive system 50 continues to output positive torque, causing the electric vehicle 10 to move forward, thereby causing the two right wheels to disengage from the wall and return to the road surface.

[0152] In one embodiment, the control method further includes controlling the suspension system of the electric vehicle 10 to increase damping after the two rear wheels turn to the right along with the two front wheels.

[0153] Increasing the damping of the suspension system refers to increasing the damping coefficient of the shock absorbers. The damping coefficient of the shock absorbers affects the vibration absorption capacity of the electric vehicle 10's suspension system. The suspension system is responsible for absorbing road vibrations and maintaining vehicle stability. Increasing damping can effectively reduce the vibration of the vehicle body caused by uneven road surfaces during driving, thereby improving vehicle stability and handling. However, increasing damping also makes the suspension stiffer, causing the electric vehicle 10 to transmit vibrations to the cabin when driving on uneven roads, thus reducing ride comfort. In narrow road driving scenarios, the electric vehicle 10 needs its two right wheels to contact the wall and climb it. During this process, the electric vehicle 10 will be affected by lateral forces, causing the body to tilt or vibrate. If the suspension damping is insufficient, the electric vehicle 10 may be unstable due to lateral swaying, affecting the smooth climbing of the wall.

[0154] In one embodiment, the control method further includes, after the two rear wheels turn to the right along with the two front wheels and before the two right wheels leave the ground, controlling the suspension system of the electric vehicle 10 to adjust the height of the right side of the electric vehicle 10 to be greater than the height of the left side of the electric vehicle 10. After the two right wheels of the electric vehicle 10 leave the ground and contact the wall, and before the steering wheel begins to return to the left, controlling the suspension system to gradually lower the height of the right side of the vehicle and gradually increase the height of the left side of the vehicle.

[0155] Before the two right wheels touch the wall, the suspension system of the electric vehicle 10 is adjusted to make the height of the right side of the electric vehicle 10 greater than the height of the left side. As the vehicle travels upwards with the two right wheels touching the wall, the suspension system gradually lowers the height of the right side of the electric vehicle 10 and gradually increases the height of the left side.

[0156] For electric vehicles 10 with adjustable body height, such as those equipped with air suspension, hydraulic active suspension, or electromagnetic active suspension systems, the vehicle height can be dynamically adjusted to assist in driving close to the wall. Before the two right wheels contact the wall, by raising the right side of the vehicle, the electric vehicle 10 can avoid rubbing against the wall and the two right wheels can more easily contact the wall, increasing friction and thus helping the electric vehicle 10 climb the wall smoothly. As the electric vehicle 10 is close to the wall and moving upwards, the suspension system dynamically adjusts the body height on both sides of the electric vehicle 10, gradually lowering the right side while increasing the left side. This helps the electric vehicle 10 maintain balance during the wall climb, reducing tilting or instability caused by the difference in horizontal height between the left and right wheels. By gradually adjusting the body height, the electric vehicle 10 can complete the wall climb more smoothly.

[0157] In one embodiment, the control method further includes controlling the suspension system of the electric vehicle 10 to maintain a constant height on the right side and left side of the vehicle body while the electric vehicle 10 is traveling close to the wall after the steering wheel has been straightened to the left. As the ground clearance of the two right wheels decreases, the suspension system is controlled to gradually increase the height of the right side of the vehicle body and gradually decrease the height of the left side until the heights of both sides are equal.

[0158] After the steering wheel is straightened to the left, the electric vehicle 10 travels close to the wall, with the suspension system maintaining a constant height on both sides of the vehicle. At this point, the height of the right side of the electric vehicle 10 is lower than that of the left side. As the two right wheels decrease in height off the ground, they gradually move from the wall to the road surface. The vehicle tilts and slowly straightens. At this time, the suspension system gradually increases the height of the right side of the vehicle and gradually decreases the height of the left side. This helps the electric vehicle 10 maintain balance during the wall-down process, reducing tilting or instability caused by the decrease in the horizontal height difference between the left and right wheels. By gradually adjusting the vehicle height, the electric vehicle 10 can more smoothly complete the wall-down maneuver. Once the two right wheels re-contact the road surface, the heights of both sides of the vehicle are equal, and the electric vehicle 10 returns to normal driving status.

[0159] It should be understood that the above-mentioned process of driving along the wall can be completed by the electric vehicle 10 with the assistance of the driver, or it can be completed autonomously by the intelligent driving system 70 of the electric vehicle 10.

[0160] This application provides another control method for an electric vehicle 10. The control method is used to automatically control the rear wheel steering system and drive system 50 of the electric vehicle 10 to cooperate with each other so that the electric vehicle 10 can pass through a narrow road after the narrow road passage function of the electric vehicle 10 is activated.

[0161] The control method includes, after the narrow road passage function is activated and before the two right wheels contact the wall on the right side of the narrow road, controlling the two front wheels of the electric vehicle 10 to turn to the right and the two rear wheels to turn to the right to a preset angle, and controlling the drive system 50 to drive the wheels of the electric vehicle 10 to rotate. After the first moment and before the second moment when the two right wheels no longer contact the surface of the narrow road, controlling the drive system 50 of the electric vehicle 10 to increase the output torque. After the second moment, controlling the two right wheels to no longer contact the surface of the narrow road and to be in contact with the wall on the right side of the narrow road.

[0162] Passing through narrow roads can be performed autonomously by the electric vehicle 10. This process can be controlled by the intelligent driving system 70 of the electric vehicle 10. The intelligent driving system 70 senses the road conditions and vehicle status and sends control signals to the rear wheel steering system and drive system 50 of the electric vehicle 10. The rear wheel steering system and drive system 50 are controlled to cooperate with each other to enable the electric vehicle 10 to automatically pass through narrow roads without the need for driver operation, which further reduces the difficulty of operation. Moreover, the control by the intelligent driving system 70 can achieve optimized operation, faster response, and higher safety.

[0163] After the driver confirms the activation of the narrow road passage function, the intelligent driving system 70 takes over control of the electric vehicle 10. It first controls the two front wheels to turn right and then controls the two rear wheels to turn right to a preset angle. It also controls the drive system 50 to output torque, thus driving the electric vehicle 10 along the wheel rotation angle. The electric vehicle 10 gradually approaches the edge of the narrow road, and at the first moment, the two right wheels contact the wall on the right side of the narrow road. At this first moment, with the two right wheels of the electric vehicle 10 against the wall, the intelligent driving system 70 controls the drive system 50 to increase the output torque, thereby increasing the contact area and pressure between the two right wheels and the wall, and gradually increasing the friction between the two right wheels and the wall.

[0164] At the second moment, the friction between the two right wheels and the wall is large enough that the two right wheels can rotate upward along the wall by relying on the friction with the wall. The two right wheels leave the road surface of the narrow road and no longer contact the road surface. As a result, the area occupied by the electric vehicle 10 in the narrow road is reduced, and the electric vehicle 10 can pass through the narrow road.

[0165] It should be understood that the electric vehicle 10 controls narrow road passage in intelligent assisted driving mode or intelligent automatic driving mode. During this process, the intelligent driving system 70 controls the drive system 50 and the rear wheel steering system without driver intervention. If the driver intervenes, the driver signal should take priority. When the driver's active operation is detected, such as turning the steering wheel, pressing the accelerator pedal, or pressing the brake pedal, the electric vehicle 10 determines that the driver has intervened, stops the automatic narrow road passage control, and responds to the driver's operation to carry out control.

[0166] In one embodiment, the control method further includes controlling the drive system 50 to adjust the output torque so that the slip ratio of the two right wheels is less than or equal to the preset slip ratio after the second moment and before the third moment when the horizontal height of the two right wheels reaches the preset value.

[0167] The intelligent driving system 70 uses a perception system to detect information such as the passable width of the narrow road, the angle between the narrow road and the wall, and the height of the wall. This allows it to determine the required horizontal height for the two right wheels to climb the wall. When the horizontal height of the two right wheels reaches a preset value, the electric vehicle 10 can pass through the narrow road. Between the second moment and the third moment when the horizontal height of the two right wheels reaches the preset value, the drive system 50 continuously monitors the slip ratio of the two right wheels and adjusts the output torque to ensure that the slip ratio of the two right wheels is less than or equal to the preset slip ratio. This maintains the friction between the wheels and the wall within a reasonable range, ensuring that the vehicle can stably adhere to the wall surface.

[0168] In one embodiment, the control method further includes, after the third moment and before the fourth moment when the steering wheel of the electric vehicle 10 turns again, controlling the steering wheel to return to center to control the front wheel and the right wheel to return to center, and driving the system 50 to drive the wheels to rotate so that the two right wheels rotate in contact with the wall.

[0169] In one embodiment, the control method further includes, after the fourth moment and before the fifth moment, when the two right wheels and the road surface of the narrow road re-contact and the two right wheels are no longer in contact with the wall on the right side of the narrow road, controlling the steering wheel to turn to the right to control the front wheels to turn to the right and controlling the rear wheels to turn to the right to a preset angle, and controlling the drive system 50 to adjust the output torque to drive the electric vehicle 10 to reverse.

[0170] After the electric vehicle 10 passes through the narrow road, the intelligent driving system 70 controls the electric vehicle 10 to return to the surface of the narrow road, controls the front wheels and the two rear wheels to turn to the right, to the same state as when climbing up the wall, and controls the drive system 50 to adjust the output torque, so that the wheels rotate in the opposite direction, the electric vehicle 10 reverses, so that the two right wheels are removed from the state of being in contact with the wall and return to the surface of the narrow road.

[0171] At the fifth moment, the four wheels of electric vehicle 10 returned to the surface of the narrow road, completing the entire narrow road passage process, and electric vehicle 10 exited the narrow road passage control.

[0172] According to the solution of this application, after the electric vehicle 10 passes through the narrow road, the wheels are controlled to turn to the right and the drive system 50 is controlled to drive the electric vehicle 10 in reverse, thereby disengaging from the wall-climbing state and safely returning to the surface of the narrow road. Driving down the wall in reverse follows a similar path to the wall-climbing process, avoiding deviation or instability of the electric vehicle 10 due to inconsistent directions.

[0173] In one embodiment, the control method further includes, after the fourth moment and before the fifth moment, when the two right wheels and the road surface of the narrow road re-contact and the two right wheels are no longer in contact with the wall on the right side of the narrow road, controlling the steering wheel to turn to the left to control the front wheels to turn to the left and controlling the rear wheels to turn to the left to a preset angle, and controlling the drive system 50 to output torque to drive the electric vehicle 10 to continue driving.

[0174] After the electric vehicle 10 passes through the narrow road, the intelligent driving system 70 controls the electric vehicle 10 to return to the surface of the narrow road, controls the front wheels and the two rear wheels to turn to the left, and controls the drive system 50 to continue to output torque, so that the electric vehicle 10 moves forward, thereby the two right wheels disengage from the state of being in contact with the wall and return to the surface of the narrow road.

[0175] According to the solution in this application, after the electric vehicle 10 passes through a narrow road, the wheels are turned to the left and the drive system 50 is controlled to propel the electric vehicle 10 forward, thereby disengaging it from the wall-climbing state and safely returning it to the surface of the narrow road. Driving down the wall by moving forward simplifies operation and improves traffic efficiency.

[0176] In one embodiment, the control method further includes, after the narrow road passage function is activated but before a first moment, controlling the suspension system of the electric vehicle 10 to increase damping and adjust the height of the right side of the electric vehicle 10 to be greater than the height of the left side of the electric vehicle 10. After a second moment but before a third moment, controlling the suspension system to gradually decrease the height of the right side of the vehicle and gradually increase the height of the left side of the vehicle. After a fourth moment, controlling the suspension system to adjust the height of the right side of the vehicle to be equal to the height of the left side of the vehicle.

[0177] In one embodiment, the control method further includes detecting the passable width of a narrow road in front of the electric vehicle 10, and prompting the driver to activate or deactivate the narrow road passage function based on the passable width of the narrow road. When the narrow road passage function is not activated, if the passable width of the narrow road is greater than a preset width but less than the body width of the electric vehicle 10, the driver is prompted to activate the narrow road passage function. If the passable width of the narrow road is less than or equal to the preset width, the driver is prompted to deactivate or the narrow road passage function cannot be activated.

[0178] When the intelligent driving system 70 detects a narrow road ahead, it needs to determine whether it is suitable to activate the narrow road passage function based on the passable width of the narrow road. The passable width refers to the width of the road surface available for the electric vehicle 10 to travel on. If the passable width of the narrow road is greater than the preset width but less than the width of the electric vehicle 10, it means that the electric vehicle 10 cannot normally pass through the narrow road. The preset width is the minimum width that the electric vehicle 10 can pass through when the narrow road passage function is activated. Because the maximum tilt of the electric vehicle 10 needs to be limited within a certain range to maintain stability when climbing walls and passing through narrow roads, the area occupied by the electric vehicle 10 in the narrow road is limited, and there is a minimum passable width limitation. When the passable width of the narrow road is less than or equal to the preset width, the electric vehicle 10 cannot pass through the narrow road smoothly even if the narrow road passage function is activated, and the driver needs to be prompted to deactivate or disable the narrow road passage function.

[0179] According to the solution in this application, the intelligent driving system 70 detects the passable width of a narrow road and prompts the driver whether the narrow road passage function can be used based on the passable width, avoiding accidental activation that could lead to driving danger, thereby improving the passability of the electric vehicle 10 in narrow road scenarios, reducing driving difficulty, and enhancing the driving experience.

[0180] When two vehicles meet on narrow roads such as those in mountainous areas, requiring one vehicle to climb over a wall to allow both vehicles to pass smoothly, or in narrow sections of roads in old towns or ancient cities where some drivers need to pass through these alleys, the traditional rear-wheel steering strategy cannot meet the needs of vehicle passage. In order to allow vehicles to pass through narrow alleys smoothly, it is necessary to design a four-wheel steering angle so that the vehicle can easily climb over walls to reduce the width of the road it occupies, thereby allowing the vehicle to pass through narrow alleys smoothly. This function can greatly improve the emotional value for car owners and the practical value of the vehicle.

[0181] The electric vehicle 10 provided in this application has a screen-based activation method for the narrow-road passage function, which can be either a soft switch or a hard wire. The driver actively activates the narrow-road passage function. When the electric vehicle 10 enters the narrow-road passage function, the rear wheel steering angle is in the same direction as the front wheel steering direction. When there is a wall on the right side of the electric vehicle 10, the driver turns the steering wheel to the right, causing the front wheels to turn to the right, and the rear wheels also turn to the right. When the electric vehicle 10 is in contact with the wall, the rightward rotation of the wheels increases the contact area and friction between the right front and right rear wheels and the wall. After maintaining this contact for a period of time, the driver slowly depresses the accelerator pedal. Guided by the rightward rotation of the right wheels, the electric vehicle 10 climbs towards the wall, eventually bringing the two left wheels of the electric vehicle 10 to the ground and the two right wheels to the wall, completing the wall-climbing action. Then, the driver returns the steering wheel to the center, bringing the two right wheels to a zero-position, and then slowly depresses the accelerator pedal again, driving the electric vehicle 10 to travel in a straight line along the wall with the vehicle tilted. After the electric vehicle 10 successfully passes through the narrow road, the driver actively turns the steering wheel to the right, causing the two right-side wheels to turn at a certain angle. At the same time, reverse gear is engaged, and the electric vehicle 10 slowly reverses off the wall, eventually coming to a smooth stop on the flat road surface. After the narrow road passage function is completed, the driver actively deactivates the function, and the electric vehicle 10 exits the narrow road passage mode.

[0182] Figure 10 This is a diagram illustrating an electric vehicle driving along a road while hugging a wall.

[0183] like Figure 10 As shown, before time t0, the narrow road passage function of the electric vehicle is not activated, the speed of the electric vehicle 10 is relatively low, and the rotation direction of the rear wheel is opposite to that of the front wheel.

[0184] At time t0, the speed of electric vehicle 10 is less than the preset speed, and electric vehicle 10 activates the narrow road passage function.

[0185] After time t0, once the steering wheel of electric vehicle 10 begins to turn to the right, both front and rear wheels of electric vehicle 10 are first controlled to turn to the right. After both front and rear wheels have turned to the right, and the accelerator pedal opening of electric vehicle 10 increases, the drive system 50 is controlled to output positive torque to drive electric vehicle 10 to move laterally to the right. After t0 or once the steering wheel begins to turn, the suspension system of electric vehicle 10 is controlled to increase damping and adjust the height of the right side of electric vehicle 10 to be greater than the height of the left side of electric vehicle 10.

[0186] At time t1, after the electric vehicle 10 moves laterally to the right until the distance between it and the wall on the right side of the road is less than a preset distance, its two right wheels contact the wall on the right side of the narrow road. With the two right wheels of the electric vehicle 10 pressed against the wall, the control drive system 50 increases the output positive torque, thereby increasing the contact area and pressure between the two right wheels and the wall, and gradually increasing the friction between the two right wheels and the wall.

[0187] At time t2, the friction between the two right wheels and the wall is large enough that the two right wheels can rotate upward along the wall by relying on the friction with the wall. The two right wheels leave the ground and abut against the wall, no longer in contact with the road surface.

[0188] After time t2, the two right wheels gradually climb up the wall, and the control suspension system gradually lowers the height of the right side of the vehicle body while gradually increasing the height of the left side of the vehicle body.

[0189] At time t3, the horizontal height of the two right wheels reaches the preset value, the steering wheel begins to return to the left, and the control drive system 50 stops outputting torque.

[0190] After time t3, the steering wheel is straightened, controlling the front and right wheels to straighten. After the steering wheel is straightened to the left, the drive system 50 outputs positive torque to drive the electric vehicle 10 to drive along the wall.

[0191] At time t4, electric vehicle 10 travels a distance closer to the wall than the preset distance and the steering wheel begins to turn to the right.

[0192] After time t4, once the steering wheel is turned to the right beyond a preset angle, the drive system 50 outputs reverse torque to drive the electric vehicle 10 backward, lowering the ground clearance of both right wheels. The suspension system then gradually increases the height of the right side of the vehicle and gradually decreases the height of the left side until both sides are at the same height.

[0193] At time t5, both right wheels re-engage with the road surface and are no longer in contact with the wall on the right side of the narrow road.

[0194] For the electric vehicle 10 equipped with an intelligent driving system, the electric vehicle 10 automatically recognizes the wall and completes the steering, automatically completes the wall climbing action, drives forward, completes the narrow road passage function, and then automatically drives to a flat road surface and exits the narrow road passage function.

[0195] According to the solution of this application, after the narrow road passage function is activated in special scenarios, the rear wheel steering system enables the rear wheel to turn in the same direction as the front wheel, so that the two right wheels contact the wall, increasing the friction and allowing one side to successfully climb the wall. This reduces the width of the road occupied by the electric vehicle 10, enabling it to smoothly complete operations such as passing on narrow roads, improving the passage capability of the electric vehicle 10 in special scenarios, enhancing the practical value of the vehicle, and providing sufficient emotional value for the driver.

[0196] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A control method for an electric vehicle, characterized by, The control method is used to control the rear-wheel steering system and drive system of the electric vehicle to cooperate with each other to enable the electric vehicle to drive close to the wall. The control method includes: During the process of the electric vehicle traveling at a speed less than a preset speed, after the steering wheel of the electric vehicle begins to turn to the right, the rear wheel steering system is controlled to drive the two rear wheels to turn to the right along with the two front wheels. After the two rear wheels turn to the right along with the two front wheels, and after the accelerator pedal opening of the electric vehicle increases, the drive system is controlled to output a first positive torque to drive the electric vehicle to move sideways to the right. After the electric vehicle moves to the right until the distance between it and the wall on the right side of the road is less than a preset distance, the drive system is controlled to output a second positive torque greater than the first positive torque so that the two right wheels of the electric vehicle leave the ground and abut against the wall.

2. The control method according to claim 1, characterized by, The control method further includes: After the two right wheels of the electric vehicle leave the ground and abut against the wall, the drive system stops outputting torque as the steering wheel begins to return to center to the left. After the steering wheel is returned to center to the left, the drive system is controlled to output a third positive torque that is less than the second positive torque to drive the electric vehicle to travel close to the wall.

3. The control method according to claim 1 or 2, characterized by, The control method further includes: After controlling the electric vehicle to travel a distance closer to the wall than a preset distance and turning the steering wheel to the right to a angle greater than a preset angle, the drive system is controlled to output reverse torque to drive the electric vehicle backward and reduce the ground clearance of the two right wheels.

4. The control method according to claim 1 or 2, characterized by, The control method further includes: After controlling the electric vehicle to travel a distance closer to the wall than a preset distance and turning the steering wheel to the left to a angle greater than a preset angle, the drive system outputs positive torque to drive the electric vehicle forward and the ground clearance of the two right wheels is reduced.

5. The control method according to claim 3, characterized by, The control method further includes: After controlling the drive system to output reverse torque to drive the electric vehicle backward and the ground clearance of the two right wheels decreases until the two rear wheels re-contact the road surface, the drive system is controlled to stop outputting the reverse torque.

6. The control method according to any one of claims 1 to 5, characterized by, The control method further includes: After the two rear wheels turn to the right along with the two front wheels, the suspension system of the electric vehicle is controlled to increase damping.

7. The control method according to any one of claims 1 to 6, characterized by, The control method further includes: After the two rear wheels turn to the right along with the two front wheels and before the two right wheels leave the ground, control the suspension system of the electric vehicle to adjust the height of the right side of the electric vehicle to be greater than the height of the left side of the electric vehicle. After the two right wheels of the electric vehicle leave the ground and abut against the wall, and before the steering wheel begins to return to the left, the suspension system is controlled to gradually lower the height of the right side of the vehicle body and gradually increase the height of the left side of the vehicle body.

8. The control method according to any one of claims 1 to 7, characterized by, The control method further includes: After the steering wheel is straightened to the left, during the process of the electric vehicle driving close to the wall, the suspension system of the electric vehicle is controlled to keep the height of the right side of the electric vehicle and the height of the left side of the electric vehicle constant. As the ground clearance of the two right wheels decreases, the suspension system is controlled to gradually increase the height of the right side of the vehicle body and gradually decrease the height of the left side of the vehicle body until the heights of both sides are equal.

9. The control method according to any one of claims 1 to 8, characterized by, The control method specifically includes: After the steering wheel begins to turn to the right, before the rightward turning angle of the rear wheel increases to a preset turning angle, the turning angles of the front wheel and the rear wheel are controlled to remain the same. After the rightward turning angle of the rear wheels increases to the preset turning angle, while the steering wheel continues to turn to the right, the rightward turning angle of the front wheels is controlled to be greater than the rightward turning angle of the rear wheels.

10. The control method according to any one of claims 1-9, characterized by, The control method specifically includes: When the angle between the road surface and the wall is the first slope, the rightward turning angle of the rear wheel is increased to the first angle. When the angle between the road surface and the wall is a second slope greater than the first slope, the rightward turning angle of the rear wheel is increased to a second angle less than the first angle.

11. The control method according to any one of claims 1 to 10, characterized by, The control method further includes: After the two right wheels of the electric vehicle leave the ground and abut against the wall, and before the steering wheel begins to return to the left, the drive system is controlled to adjust the output torque so that the slip ratio of the two right wheels is less than or equal to the preset slip ratio.

12. The control method according to any one of claims 1-11, characterized by, The control method specifically includes: After the two right wheels of the electric vehicle leave the ground and abut against the wall, when the difference between the horizontal height of the two right wheels and the horizontal height of the two left wheels increases to a preset height, the drive system is controlled to stop outputting torque. During the process of controlling the electric vehicle to drive close to the wall, the difference between the horizontal height of the two right wheels and the horizontal height of the two left wheels is controlled to be less than or equal to a preset height.

13. The control method according to any one of claims 1-12, characterized by, The control method further includes: During the process of controlling the electric vehicle to drive close to the wall, the passable width of the road surface in front of the electric vehicle is detected; When the passable width of the road surface is less than or equal to the preset width, the drive system is controlled to stop outputting torque.

14. A vehicle controller for an electric vehicle, characterized by The vehicle controller is used to implement the control method as described in any one of claims 1-13.

15. An electric vehicle, characterized in that, The electric vehicle includes a drive system, an accelerator pedal, a steering wheel, and a vehicle controller as described in claim 14, wherein the accelerator pedal is used to instruct the drive system to output torque to the wheels of the electric vehicle, and the steering wheel is used to instruct the steering angle of the wheels of the electric vehicle.

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