Control method of electric vehicle, controller and electric vehicle

Abstract

The invention provides a control method of an electric vehicle, a controller and the electric vehicle. When the roll angle of a vehicle body of the electric vehicle is increased to be larger than a first preset value, the steering angles of front wheels and rear wheels of the electric vehicle are controlled to increase the included angle between the direction of a vehicle head of the vehicle and the centroid speed direction; the stable force arm of the electric vehicle is increased. After the stabilizing moment arm is increased, the stabilizing moment of the electric vehicle can be further increased, so that the capability of the electric vehicle for resisting the roll-over moment is enhanced, the roll-over risk of the vehicle is reduced, and the life safety of passengers is guaranteed.

Description

Technical Field

[0001] This application relates to the field of new energy vehicle technology, and in particular to a control method, controller, and electric vehicle for electric vehicles. Background Technology

[0002] When vehicles travel on public roads, they often encounter various unexpected situations due to complex road conditions. For example, a vehicle ahead may suddenly stop or an obstacle may suddenly appear. When an emergency occurs, the driver will instinctively take emergency control of the vehicle to avoid an accident. However, in such an emergency, drivers often find it difficult to react appropriately, easily leading to over-control and causing the vehicle to overturn while trying to avoid the vehicle or obstacle, posing a significant threat to the lives of the occupants.

[0003] Therefore, ensuring the safety of passengers is an urgent problem to be solved. Summary of the Invention

[0004] This application provides a control method, controller, and electric vehicle for an electric vehicle. By controlling the direction of the electric vehicle's front end, the ability of the electric vehicle to resist rollover is improved, thereby effectively ensuring the safety of the occupants.

[0005] To achieve the above objectives, this application adopts the following technical solution:

[0006] Firstly, a control method for an electric vehicle is provided, the control method comprising:

[0007] During the turning process of the electric vehicle, before the body roll angle of the electric vehicle increases to a first preset value, the front and rear wheels of the electric vehicle are controlled to turn with the steering wheel. After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled to increase the angle between the direction of the vehicle's nose and the direction of the center of gravity velocity.

[0008] Electric vehicles experience two forces during steering: the vehicle's own weight and the centripetal force generated by the steering motion. The centripetal force produces a roll moment that can cause the vehicle to overturn, while gravity generates a stabilizing moment that opposes the roll moment and resists it. From the perspective of force relationships, whether an electric vehicle overturns depends on the interaction between the stabilizing moment and the roll moment. When the stabilizing moment is greater than the roll moment, the vehicle will not overturn or the roll angle will decrease; when the stabilizing moment is less than the roll moment, the vehicle will overturn or the roll angle will increase.

[0009] The magnitude of the stabilizing torque of an electric vehicle is primarily determined by the length of its stabilizing arm. A longer stabilizing arm results in a larger stabilizing torque, while a shorter stabilizing arm results in a smaller stabilizing torque. Furthermore, since the stabilizing arm length during a turn is the distance between the vehicle's center of gravity and the outer steering wheel in the centripetal force direction, a longer distance between these two points results in a larger stabilizing torque and a lower risk of rollover.

[0010] When the angle between the direction of the electric vehicle's front and the direction of its center of mass velocity increases during a turn, the actual motion of the electric vehicle during the turn can be considered as a composite of two component motions. One component motion is the turning motion of the electric vehicle as a whole on the road. In this component motion, the electric vehicle is considered as a point mass located at the center of mass, and this component motion can be called the electric vehicle's revolution motion. The other component motion is the rotational motion of the electric vehicle about its center of mass, and this component motion can be called the electric vehicle's rotational motion.

[0011] In this embodiment, a higher risk of rollover for the electric vehicle is accurately determined by detecting a body roll angle greater than a first preset value. Furthermore, when the body roll angle exceeds the first preset value, the steering angles of the front and rear wheels are actively controlled to increase the angle between the vehicle's frontal orientation and the direction of its center of gravity velocity. This causes the electric vehicle to rotate along a direction that increases the distance between the vehicle's center of gravity and the outer steering wheel in the centripetal force direction, thereby increasing the stabilizing arm. The increased stabilizing arm further increases the vehicle's stabilizing torque, enhancing its ability to counteract rollover torque, reducing the risk of rollover, and ultimately ensuring the safety of the occupants.

[0012] In one implementation of the first aspect, the control method further includes:

[0013] After the steering wheel begins to straighten, the steering angle of the front or rear wheels of the electric vehicle is actively controlled to reduce the angle between the direction of the electric vehicle's front and the direction of its center of gravity velocity.

[0014] When the angle between the heading and the velocity direction of an electric vehicle increases, the vehicle will turn with a tilt towards the road. This tilt increases the road width required for the electric vehicle to travel, thus reducing its maneuverability. Therefore, increasing the angle between the heading and the velocity direction before the steering wheel begins to straighten, while reducing the risk of rollover, also negatively impacts the vehicle's performance. Based on this, this embodiment further reduces the angle between the heading and the velocity direction after the rollover risk is eliminated. This reduces the required road width, restoring the vehicle's maneuverability to normal levels and ensuring smooth driving.

[0015] In one implementation of the first aspect, the control method further includes: after the body roll angle of the electric vehicle increases to a first preset value, before the steering wheel begins to return to center, actively controlling the steering angle of the front and rear wheels of the electric vehicle to increase the angle between the vehicle's heading and the direction of the center of gravity velocity to the point where the vehicle's heading is perpendicular to the direction of the center of gravity velocity.

[0016] The distance between the center of gravity of an electric vehicle and the outer steering wheel in the direction of centripetal force increases as the angle between the vehicle's heading and the velocity of the center of gravity increases. Therefore, when the angle between the vehicle's heading and the velocity of the center of gravity reaches its maximum, that is, when the vehicle's heading is perpendicular to the velocity of the center of gravity, the distance between the center of gravity of the electric vehicle and the outer steering wheel in the direction of centripetal force also reaches its maximum. At this point, the electric vehicle's ability to resist roll moment is strongest.

[0017] This embodiment increases the angle between the electric vehicle's frontal orientation and the direction of its center of gravity velocity to the point where the electric vehicle's frontal orientation is perpendicular to the direction of its center of gravity velocity. This maximizes the electric vehicle's ability to counteract roll moment, thereby eliminating the risk of roll at the fastest speed when the electric vehicle is at risk of roll, and fully protecting the lives of the occupants.

[0018] In one implementation of the first aspect, the control method further includes:

[0019] After the body roll angle of the electric vehicle increases to the first preset angle preset value, before the steering wheel begins to return to center, the front wheels are actively controlled to turn to the left and the rear wheels are controlled to turn to the right during the left turn.

[0020] In this embodiment, during the process of the electric vehicle turning left, the front wheels are actively controlled to turn left and the rear wheels are controlled to turn right. On the basis of the basic steering force provided by the front wheels, the right turn of the rear wheels generates an additional yaw moment. The superposition of the two promotes the increase of the angle between the vehicle's heading and the direction of the execution speed, thereby improving the electric vehicle's ability to suppress body roll.

[0021] In one implementation of the first aspect, the control method further includes:

[0022] After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled so that the angle between the direction of the electric vehicle's front and the direction of the center of gravity velocity increases and the turning radius of the electric vehicle remains unchanged during the turning process.

[0023] The turning radius is the distance between the center of mass of an electric vehicle and the center of revolution when the vehicle is in revolution. During the turning process of an electric vehicle, the magnitude of the centripetal force is determined by the turning radius; the larger the turning radius, the smaller the centripetal force, and vice versa.

[0024] Therefore, by increasing the angle between the electric vehicle's frontal orientation and the direction of its center of gravity velocity while keeping the vehicle's turning radius constant, this application can increase the vehicle's stabilizing torque while preventing an increase in rollover torque, thus providing a strong guarantee against rollover risk. Furthermore, keeping the electric vehicle's turning radius constant during turning ensures that the vehicle still conforms to the driver's steering intention before the steering wheel begins to return to center when the steering controller actively controls it. This avoids the driver's misjudgment of losing control of the electric vehicle, reduces the probability of over-control, and ultimately improves the safety of the electric vehicle.

[0025] In one implementation of the first aspect, the control method further includes:

[0026] After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled to increase the angle between the direction of the electric vehicle's front and the direction of the center of gravity velocity, and the turning radius of the electric vehicle increases during the turning process.

[0027] This application increases the angle between the frontal orientation of the electric vehicle and the direction of the center of gravity velocity, while also increasing the turning radius of the electric vehicle. This increases the stabilizing torque of the electric vehicle while reducing the centripetal force to decrease the roll torque, thereby increasing the difference between the stabilizing torque and the roll torque and promoting the elimination of roll risk in the electric vehicle.

[0028] In one implementation of the first aspect, the control method further includes:

[0029] After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, and when there are no obstacles in the direction of the electric vehicle's movement, the steering angles of the front and rear wheels of the electric vehicle are actively controlled to increase the angle between the electric vehicle's front-facing direction and the direction of its center of gravity velocity, and the turning radius of the electric vehicle increases during the turning process.

[0030] While increasing the turning radius, electric vehicles also alter their travel path. When this path changes, if an obstacle exists in the direction of travel, the driver may panic and jerk the steering wheel, potentially causing the vehicle to lose control. Therefore, this embodiment determines whether an obstacle exists in the direction of travel before increasing the turning radius. Only when no obstacle exists in the direction of travel will the steering angles of the front and rear wheels be actively controlled. This prevents the vehicle from losing control due to driver input and improves vehicle safety.

[0031] In one implementation of the first aspect, the control method further includes:

[0032] When the road traveled by the electric vehicle is of a first width, the angle between the vehicle's heading and the direction of its center of gravity velocity is less than a first angle. When the road traveled by the electric vehicle is of a second width less than the first width, the angle between the vehicle's heading and the direction of its center of gravity velocity is less than a second angle, and the second angle is less than the first angle.

[0033] The angle between the vehicle's heading and the direction of its center of gravity velocity is limited by the environment in which the electric vehicle is located. When the angle between the electric vehicle's heading and the direction of its center of gravity velocity increases, the electric vehicle will turn in a tilted posture relative to the road direction. This tilted posture will require a wider road for the electric vehicle to travel on, thus reducing its maneuverability.

[0034] When the road width for electric vehicles is a larger first width, the road allows wider electric vehicles to pass. In this embodiment, by controlling the angle between the electric vehicle's frontal orientation and its center of gravity velocity direction to be smaller than the larger first angle on a wider road, the anti-rollover capability of the electric vehicle can be fully utilized.

[0035] When the road width for electric vehicles is the smaller of the second widths, only electric vehicles with narrower widths can pass through the road. In this embodiment, on narrower roads, by controlling the angle between the electric vehicle's heading and its center of gravity velocity direction to be smaller than the smaller second angle, the increase in the required road width for electric vehicles can be limited, ensuring smooth turning for electric vehicles.

[0036] In one implementation of the first aspect, the control method further includes:

[0037] Before the body roll angle of the electric vehicle increases to a second preset value, the braking torque of the electric vehicle is controlled to be zero, where the second preset value is less than the first preset value. After the body roll angle of the electric vehicle increases to the second preset value, the braking torque of the electric vehicle is controlled to increase from zero.

[0038] The centripetal force of an electric vehicle during cornering varies with its speed; the higher the speed, the greater the centripetal force, and vice versa. In this implementation, after the vehicle's roll angle increases to a second preset value, the braking torque is increased from zero. This reduces the vehicle's speed, thereby decreasing the centripetal force and, consequently, the roll moment. The reduction in roll moment increases the vehicle's ability to suppress roll, ultimately achieving roll suppression.

[0039] In one implementation of the first aspect, the control method further includes:

[0040] After the body roll angle of the electric vehicle increases to the second preset value, the rate of increase of the control braking torque increases as the rate of increase of the body roll angle increases.

[0041] The greater the rate of increase in the vehicle's roll angle, the greater the gap between the actual roll suppression capability and the required roll suppression capability of the electric vehicle. Therefore, to further ensure the roll suppression effect, this embodiment controls the rate of increase of the braking torque to increase with the rate of increase of the vehicle's roll angle. This allows the electric vehicle to adaptively adjust the roll suppression force according to the current situation, matching the force of the control intervention with the urgency of roll suppression, resulting in smoother dynamic movement of the electric vehicle.

[0042] In one implementation of the first aspect, the control method further includes:

[0043] Before the electric vehicle's body roll angle increases to a third preset value, the actuators controlling the suspension system output a first working force, where the third preset value is less than the first preset value. After the electric vehicle's body roll angle increases to the third preset value, the actuators controlling the suspension system output a second working force, where the second working force is greater than the first working force.

[0044] After the suspension system outputs its second working force, the suspension stiffness of the electric vehicle is increased compared to when the actuator outputs its first working force. Greater suspension stiffness allows the electric vehicle to produce a smaller body roll angle under the same lateral force, thereby reducing the lateral shift of the electric vehicle's center of gravity. Since lateral shift of the center of gravity leads to a shortening of the stabilizer arm, this embodiment reduces the amount of stabilizer arm shortening by increasing suspension stiffness, thus preventing excessive reduction in the stabilizing torque and ensuring the electric vehicle's rollover prevention capability.

[0045] In one implementation of the first aspect, the control method further includes:

[0046] After the body roll angle of the electric vehicle increases to the third preset value, the second actuation force output by the control actuator increases as the suspension height of the electric vehicle increases.

[0047] With the same body roll angle, the higher the suspension height of an electric vehicle, the greater the lateral offset of its center of gravity. This embodiment controls the second action force to increase with the increase of suspension height, thereby reducing the body roll angle of electric vehicles with higher suspension heights. This prevents the stabilizing arm of high-suspension-height electric vehicles from decreasing excessively, thus reducing the risk of rollover.

[0048] Secondly, this application provides a controller for an electric vehicle, the controller being used for:

[0049] During the turning process of the electric vehicle, before the body roll angle of the electric vehicle increases to a first preset value, the front and rear wheels of the electric vehicle are controlled to turn with the steering wheel. After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled to increase the angle between the direction of the vehicle's nose and the direction of the center of gravity velocity.

[0050] In one implementation of the second aspect, the controller can also be used for:

[0051] After the steering wheel begins to straighten, the steering angle of the front or rear wheels of the electric vehicle is actively controlled to reduce the angle between the direction of the electric vehicle's front and the direction of its center of gravity velocity.

[0052] In one implementation of the second aspect, the controller can also be used for:

[0053] After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled so that the angle between the vehicle's heading and the direction of the center of gravity velocity increases to the point where the vehicle's heading is perpendicular to the direction of the center of gravity velocity.

[0054] In one implementation of the second aspect, the controller can also be used for:

[0055] After the body roll angle of the electric vehicle increases to the first preset angle preset value, before the steering wheel begins to return to center, the front wheels are actively controlled to turn to the left and the rear wheels are controlled to turn to the right during the left turn.

[0056] In one implementation of the second aspect, the controller can also be used for:

[0057] After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled so that the angle between the direction of the electric vehicle's front and the direction of the center of gravity velocity increases and the turning radius of the electric vehicle remains unchanged during the turning process.

[0058] In one implementation of the second aspect, the controller can also be used for:

[0059] After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled to increase the angle between the direction of the electric vehicle's front and the direction of the center of gravity velocity, and the turning radius of the electric vehicle increases during the turning process.

[0060] In one implementation of the second aspect, the controller can also be used for:

[0061] After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, and when there are no obstacles in the direction of the electric vehicle's movement, the steering angles of the front and rear wheels of the electric vehicle are actively controlled to increase the angle between the electric vehicle's front-facing direction and the direction of its center of gravity velocity, and the turning radius of the electric vehicle increases during the turning process.

[0062] In one implementation of the second aspect, the controller can also be used for:

[0063] When the road on which the electric vehicle travels is of the first width, the angle between the direction of the electric vehicle's front and the direction of its center of gravity velocity is less than the first angle.

[0064] When the road on which the electric vehicle travels is a second width that is less than the first width, the angle between the direction the electric vehicle is facing and the direction of its center of gravity velocity is less than the second angle, and the second angle is less than the first angle.

[0065] In one implementation of the second aspect, the controller can also be used for:

[0066] Before the body roll angle of the electric vehicle increases to the second preset value, the braking torque of the electric vehicle is controlled to be zero, and the second preset value is less than the first preset value;

[0067] After the body roll angle of the electric vehicle increases to the second preset value, the braking torque of the electric vehicle is controlled to increase from zero.

[0068] After the body roll angle of the electric vehicle increases to the second preset value, the rate of increase of the control braking torque increases as the rate of increase of the body roll angle increases.

[0069] In one implementation of the second aspect, the controller can also be used for:

[0070] Before the body roll angle of the electric vehicle increases to the third preset value, the actuator of the control suspension system outputs the first driving force, and the third preset value is less than the first preset value;

[0071] After the body roll angle of the electric vehicle increases to the third preset value, the actuator controlling the suspension system outputs a second working force, which is greater than the first working force.

[0072] In one implementation of the second aspect, the controller can also be used for:

[0073] After the body roll angle of the electric vehicle increases to the third preset value, the second actuation force output by the control actuator increases as the suspension height of the electric vehicle increases.

[0074] Thirdly, this application provides an electric vehicle, which includes a corner module and a controller. The corner module is used to drive the front and rear wheels of the electric vehicle to rotate, and the controller is used to execute the control method of the electric vehicle as described in the first aspect and various embodiments of the first aspect.

[0075] Specifically, other beneficial effects can be referred to the beneficial effects described in the first aspect, and will not be repeated here. Attached Figure Description

[0076] Figure 1 A schematic diagram of a vehicle architecture provided for an embodiment of this application;

[0077] Figure 2 A structural diagram of a steering system provided in an embodiment of this application;

[0078] Figure 3 A schematic diagram illustrating the change in the angle between the vehicle's front orientation and the velocity direction of its center of gravity, provided in an embodiment of this application;

[0079] Figure 4 A schematic diagram illustrating the change in the angle between the vehicle's front orientation and the direction of its center of gravity velocity, provided as an embodiment of this application;

[0080] Figure 5 This application provides a force diagram illustrating the process of a vehicle turning.

[0081] Figure 6 This application provides another force diagram illustrating the process of a vehicle turning.

[0082] Figure 7 This is a schematic diagram of the motion analysis of a vehicle during turning, provided in an embodiment of this application.

[0083] Figure 8 A control timing diagram for a vehicle provided in an embodiment of this application;

[0084] Figure 9 This is a flowchart of a vehicle control method provided in an embodiment of this application. Detailed Implementation

[0085] 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.

[0086] It should be noted that, in this application, the terms "exemplary" or "for example" are used to indicate that something is being described as an example, illustration, or illustration. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or design solutions. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0087] When vehicles travel on public roads, they often encounter various unexpected situations due to complex road conditions. For example, a vehicle ahead may suddenly stop or an obstacle may suddenly appear. When an unexpected situation occurs, the driver will instinctively take emergency control of the vehicle, such as by sharply turning the steering wheel, to avoid an accident. However, under this highly stressful state, the driver's judgment and actions are very likely to exceed reasonable limits, resulting in over-control.

[0088] When a driver makes an over-control maneuver, such as suddenly jerking the steering wheel, the vehicle experiences a violent lateral shift in its center of gravity. A higher center of gravity causes centrifugal force to rapidly throw most of the vehicle's weight to one side during a sharp turn, resulting in a drastic reduction in load on the opposite wheel. If this weight shift continues from one side to the other, the vehicle will eventually overturn due to inertia, causing a rollover accident that poses a significant threat to the lives of the occupants.

[0089] To ensure occupant safety, one possible approach is to reduce the vehicle's rollover risk by lowering its center of gravity. However, for most vehicles, reducing vehicle height can only be achieved during the design phase by lowering the chassis height, and an excessively low chassis height can reduce the vehicle's ground clearance.

[0090] To address the aforementioned problems, this application provides a control method, controller, and electric vehicle for an electric vehicle. When the roll angle of the electric vehicle increases to a value greater than a first preset value, the stabilizing arm of the electric vehicle is increased by increasing the angle between the vehicle's frontal orientation and the direction of its center of gravity velocity. This increase in the stabilizing arm further increases the stabilizing torque of the electric vehicle, enhancing its ability to counteract roll torque, thereby reducing the risk of rollover and ensuring the safety of occupants.

[0091] The following section will introduce the vehicle architecture and system architecture on which this application is based.

[0092] See Figure 1 , Figure 1 This is a schematic diagram of a vehicle architecture provided in an embodiment of this application.

[0093] Vehicle 10 may be an electric vehicle. For example... Figure 1 As shown, the vehicle 10 includes a drive system 110, a braking system 120, a steering system 130, a suspension system 140, a power battery 150 connected to the drive system 110, and a vehicle controller 160 connected to the drive system 110, braking system 120, steering system 130, and suspension system 140 respectively. The drive system 110 outputs driving force to drive the vehicle 10; the braking system 120 outputs braking force to brake the vehicle 10; the steering system 130 adjusts the wheel deflection angle of the vehicle 10 to control the steering of the vehicle 10; the suspension system 140 adjusts the suspension stiffness; the power battery 150 provides electrical energy to the drive system 110; and the vehicle controller 160 controls the driving force output by the drive system 110, the braking force output by the braking system 120, the wheel deflection angle of the steering system 130, and the suspension stiffness adjusted by the suspension system 140.

[0094] The four wheels of vehicle 10 can be divided into front wheels 170 and rear wheels 180 according to the axle to which they are connected. The front wheels 170 are connected to the front axle of vehicle 10, and the rear wheels 180 are connected to the rear axle of vehicle 10. The front wheels 170 can also be divided into left front wheels and right front wheels according to their positions, and the rear wheels 180 can also be divided into left rear wheels and right rear wheels according to their positions.

[0095] In this application embodiment, the vehicle 10 can be any type of automobile, such as a sedan, truck, or passenger bus, or it can be a tricycle, two-wheeled vehicle, train, or other transportation device for carrying passengers or goods, or other types of vehicles powered by the power battery 150. This application embodiment does not limit this. The vehicle 10 includes, but is not limited to, pure electric vehicles (pure EV / battery EV), hybrid electric vehicles (HEV), range-extended electric vehicles (REEV), plug-in hybrid electric vehicles (PHEV), and new energy vehicles (NEV).

[0096] The drive system 110 can be referred to as a powertrain. This application does not limit the specific type of the drive system 110; it is merely an example and not a limitation. The drive system 110 can be a centralized drive system, a hub motor drive system, or a wheel-side motor drive system. In the hub motor drive system, the drive motor 111 and the reducer are directly mounted in the wheel rim, eliminating transmission components such as half-shafts, universal joints, differentials, and gearboxes. In the wheel-side motor drive system, the drive motor 111 is mounted on the subframe.

[0097] The braking system 120 can be either a hydraulic braking system or an electromechanical braking system. A hydraulic braking system uses brake fluid as an incompressible transmission medium, transmitting pedal force to the brake cylinders of each wheel via the master cylinder and brake lines to achieve braking. An electromechanical braking system eliminates the hydraulic lines, directly driving the brake calipers through a brake motor 121 located at the wheel end. The braking system 120 includes a brake motor 121 and a brake controller 122 connected to the brake motor 121. The brake motor 121 outputs braking torque to the wheels, and the brake controller 122 controls the output braking torque from the brake motor 121 to the wheels.

[0098] The steering system 130 includes a steering motor 131 and a steering controller 132 connected to the steering motor 131. The steering motor 131 drives the wheels to rotate, and the steering controller 132 controls the steering motor 131 to drive the wheels to rotate. (Reference) Figure 2 The diagram shows a structural diagram of a steering system. Specifically, the steering system 130 in this application can be as follows: Figure 2 The distributed steering system shown is a steering system capable of independently controlling the steering of multiple wheels of a vehicle 10. It includes multiple steering motors 131, each driving one wheel to rotate. The motion of the wheels in the distributed steering system 130 is decoupled, allowing the front wheels 170 and rear wheels 180 to rotate in different directions and at different angles.

[0099] When the drive system 110 is a hub motor drive system, the braking system 120 is an electromechanical braking system, and the steering system 130 is a distributed steering system, the hub motor in the drive system 110, the brake motor 121 in the braking system 120, and the steering motor 131 in the steering system 130, corresponding to each wheel, can be integrated with the shock absorber or spring in the suspension system 140 corresponding to that wheel, forming a single corner module that integrates the functions of the suspension system 140, the braking system 120, the drive system 110, and the steering system 130. Correspondingly, the control functions of the drive controller 112 of the drive system 110, the brake controller 122 of the braking system 120, the steering controller 132 of the steering system 130, and the suspension controller 142 of the suspension system 140 can also be integrated into the same corner module controller. The vehicle 10 can be equipped with multiple corner modules, each used to drive a different wheel.

[0100] The suspension system 140 can be an air suspension or a hydraulic suspension. Taking an air suspension as an example, the structure of the suspension system 140 is described as follows: The suspension system 140 includes an air spring and an air supply module for the air spring, shock absorbers, and an active stabilizer bar. The air spring and the air supply module for the air spring can adjust the vehicle height 10 by changing the air volume of the air spring. The shock absorbers are used to absorb the vibration energy transmitted from the ground to the vehicle body during vehicle 10 operation, thereby improving passenger comfort.

[0101] The active stabilizer bar includes a torsion bar connected to the wheel and an actuator 141 connected to the torsion bar. The actuator 141 changes the stiffness of the suspension system 140 by altering the force it outputs to the torsion bar. The greater the force output by the actuator 141, the greater the stiffness of the suspension system 140; the smaller the force output by the actuator 141, the smaller the stiffness of the suspension system 140.

[0102] Depending on the medium used to adjust suspension stiffness, active stabilizer bars can be divided into hydraulic and electromechanical types. The actuator 141 of a hydraulic active stabilizer bar is a hydraulic pump, while the actuator 141 of an electromechanical active stabilizer bar is an electric motor. Taking the electromechanical active stabilizer bar as an example, the specific process of adjusting suspension stiffness with an active stabilizer bar will be introduced:

[0103] In response to receiving an instruction to increase suspension stiffness, the suspension controller 142 sends a control command to the motor. The motor, in response to the control command from the suspension controller 142, outputs a force capable of resisting torsion to the torsion bar connected to the motor output shaft, according to the parameters such as output torque and rotation direction indicated by the control command. This resists torsion to prevent suspension deformation under roll forces, ultimately achieving the goal of increasing suspension stiffness.

[0104] The power battery 150 in this embodiment can be a lithium-ion battery, lithium metal battery, lead-acid battery, nickel-cadmium battery, nickel-metal hydride battery, lithium-sulfur battery, lithium-air battery, or sodium-ion battery, etc., and this application does not limit its application to this type. In terms of scale, the power battery 150 in this embodiment can be a single cell, a battery module, or a battery pack, and this application does not limit its application to this type. The power battery 150 can also supply power to other electrical devices in the vehicle 10, such as the vehicle's air conditioning and in-vehicle media player.

[0105] The following combination Figure 1 The vehicle 10 architecture is shown, and the control method of the vehicle 10 provided in this application is described in detail.

[0106] During a turn, the driver turns the steering wheel according to their intended direction. As the driver turns the steering wheel, a steering wheel angle sensor mounted on the steering column collects the steering wheel angle and generates a steering wheel angle signal, which is then sent to the steering controller 132. Simultaneously, a gyroscope or inertial measurement unit (IMU) mounted on the vehicle body generates a body roll angle signal based on the collected body roll angle and sends it to the steering controller 132.

[0107] After receiving the vehicle roll angle signal and the steering wheel angle signal, if the steering controller 132 determines that the vehicle roll angle of the vehicle 10 has not yet increased to a first preset value (i.e., before the vehicle roll angle increases to the first preset value), it will control the front wheels 170 and the rear wheels 180 to rotate in a manner corresponding to the steering wheel, according to the steering wheel angle indicated by the steering wheel angle signal, so that the front wheels 170 and the rear wheels 180 rotate with the rotation of the steering wheel. Figure 3 The diagram shows the change in the angle between the vehicle's front orientation and the direction of its center of gravity velocity. When the front wheel 170 and the rear wheel 180 rotate with the steering wheel, the vehicle's front orientation and the direction of its center of gravity velocity do not change during the turning process of the vehicle 10.

[0108] If it is determined that the body roll angle of vehicle 10 has increased to a value greater than the first preset value (i.e., after the body roll angle has increased to a value greater than the first preset value), then before the steering wheel signal indicates that the steering wheel has begun to return to center, the steering angles of the front wheels 170 and the rear wheels 180 of vehicle 10 are actively controlled so that the angle between the vehicle 10's frontal orientation and the direction of its center of gravity velocity is as follows: Figure 4 Another schematic diagram showing the change in the angle between the vehicle's frontal orientation and the direction of the center of gravity velocity illustrates that the angle gradually increases during the turning process of vehicle 10. In this embodiment, "actively controlling the steering angles of the front wheels 170 and rear wheels 180 of vehicle 10" means that the steering controller 132 does not control the wheel steering based on the steering wheel angle signal, but rather controls the wheel steering itself.

[0109] In this embodiment, the risk of rollover of the electric vehicle is determined to be high by detecting a body roll angle greater than a first preset value, thus requiring steering control. The first preset value can be set according to requirements, for example, it can be 15°, 16° or 17°.

[0110] As an example, after the body roll angle of the electric vehicle increases to a first preset angle preset value, before the steering wheel begins to return to center, the front wheels 170 can be actively controlled to turn further to the left and the rear wheels 180 to turn to the right during a left turn of the vehicle 10, or the front wheels 170 can be actively controlled to turn further to the right and the rear wheels 180 to turn to the left during a right turn of the vehicle 10. The control method of this embodiment will be illustrated below using actual scenarios of the vehicle 10 turning left and right as examples.

[0111] During a left turn of vehicle 10, when the steering wheel is turned to the left by the driver, before the body roll angle of vehicle 10 increases to a first preset value, the steering controller 132 controls the front wheels 170 to turn left along with the steering wheel. Simultaneously, the steering controller 132 can also control the rear wheels 180 to turn left or right along with the steering wheel, depending on the driving mode of vehicle 10. For example, when the driving mode of vehicle 10 is agile steering mode, the steering controller 132 can control the rear wheels 180 to turn right along with the steering wheel, thereby reducing the turning radius of vehicle 10 and improving its steering agility; when the driving mode of vehicle 10 is comfort mode, the steering controller 132 can control the rear wheels 180 to turn left along with the steering wheel, thereby increasing the turning radius of vehicle 10 and improving its ride comfort.

[0112] After the body roll angle of vehicle 10 increases to the first preset value, before the steering wheel starts to turn to the right under the driver's operation and before it starts to return to center, the front wheel 170 is actively controlled to turn further to the left and the rear wheel 180 is controlled to turn to the right, so as to increase the angle between the direction of the vehicle 10's front and the direction of the center of gravity velocity.

[0113] During the right turn of vehicle 10, the steering controller 132 can be controlled by referring to the control process for a left turn. The specific control method of the steering controller 132 when vehicle 10 is making a right turn is similar to that when making a left turn, and will not be described again in this embodiment.

[0114] During a turn, vehicle 10 is subjected to two forces: its own weight and the centripetal force generated by the turning motion. The centripetal force generates a roll moment that can cause vehicle 10 to overturn, while gravity generates a stabilizing moment that is opposite in direction to the roll moment and can resist overturning. From the perspective of force relationships, whether vehicle 10 overturns is the result of the interaction between the stabilizing moment and the roll moment. When the stabilizing moment is greater than the roll moment, vehicle 10 will not overturn or the roll angle will decrease; when the stabilizing moment is less than the roll moment, vehicle 10 will overturn or the roll angle will increase.

[0115] The magnitude of the stabilizing torque of vehicle 10 is mainly determined by the length of the stabilizing arm. A longer stabilizing arm results in a larger stabilizing torque, while a shorter stabilizing arm results in a smaller stabilizing torque. During steering, the length of the stabilizing arm of vehicle 10 is the distance between the vehicle 10's center of gravity and the outer steering wheel in the direction of centripetal force. Figure 5 A force diagram showing the process of a vehicle turning is shown. Figure 6 The diagram illustrates another force distribution during a vehicle's turn, as shown below. When vehicle 10... Figure 5 When the vehicle 10 is driving through a curve in the state shown, the distance between the center of gravity of the vehicle 10 and the outer steering wheel in the direction of centripetal force is approximately half the track width of the vehicle 10. In other words, in this state, the stabilizing arm length of the vehicle 10 is approximately half the track width. When the vehicle 10... Figure 6 When the vehicle 10 is driving through a curve in the state shown, the distance between the center of gravity of the vehicle 10 and the outer steering wheel in the direction of centripetal force is about half the wheelbase of the vehicle 10. In other words, in this state, the length of the stabilizing arm of the vehicle 10 is about half the wheelbase.

[0116] Because the wheelbase of vehicle 10 is greater than the track width, vehicle 10 is... Figure 6 The stabilizing lever arm in the shown state is greater than that in Figure 5 The stabilizing lever arm is shown in the diagram. From this, it can be concluded that as vehicle 10 approaches [a certain point] during its movement... Figure 6 As shown, the greater the stabilizing torque, the lower the risk of rollover; the closer vehicle 10 is to... Figure 5 As shown in the diagram, the smaller the stabilizing torque, the greater the risk of rollover.

[0117] When the angle between the vehicle 10's nose direction and the direction of its center of mass velocity increases during cornering, the actual motion of the vehicle 10 can be considered as a synthesis of two component motions. (Reference) Figure 7The diagram illustrates the motion analysis of a vehicle during a turn. One component of the actual motion of the composite vehicle 10 is the turning motion of the vehicle as a whole on the road, which can be called the revolution motion of the vehicle 10. In this component motion, the vehicle 10 is considered as a point mass located at the center of mass. The other component motion is the rotational motion of the vehicle 10 about its center of mass, which can be called the rotational motion of the vehicle 10. The rotational motion of the vehicle 10 can cause the vehicle 10 to turn from its center of mass to its rotational center. Figure 5 The state shown Figure 6 The state transition shown increases the stabilizing arm of vehicle 10. This increase in the stabilizing arm further increases the stabilizing moment of vehicle 10, enhancing its ability to counteract rollover moments, reducing the risk of rollover, and ultimately ensuring the safety of occupants.

[0118] In one embodiment, after the body roll angle of the electric vehicle 10 increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front wheel 170 and the rear wheel 180 of the vehicle 10 is actively controlled so that the angle between the vehicle 10's heading and the center of gravity velocity direction increases to the point where the vehicle 10's heading is perpendicular to the center of gravity velocity direction.

[0119] The distance between the center of gravity of vehicle 10 and the outer steering wheel in the direction of centripetal force increases as the angle between the vehicle's heading and the velocity of the center of gravity increases. Therefore, when the angle between the vehicle's heading and the velocity of the center of gravity increases to its maximum, vehicle 10 will be in the following position: Figure 6 In the state shown, the length of the stabilizing arm is at its maximum. At this point, vehicle 10 has the strongest ability to resist roll moment.

[0120] This embodiment increases the angle between the vehicle 10's front orientation and the center of gravity velocity direction to the point where the vehicle 10's front orientation is perpendicular to the center of gravity velocity direction. This maximizes the vehicle 10's ability to resist roll moment, thereby eliminating the roll risk as quickly as possible when the vehicle 10 is at risk of roll, and fully protecting the lives of the occupants.

[0121] However, the angle between the vehicle's heading and the direction of its center of gravity velocity is also limited by the environment in which the vehicle 10 is located. When the angle between the vehicle's heading and the direction of its center of gravity velocity increases, the vehicle 10 will turn in a tilted posture relative to the road direction. This tilted posture requires a wider road for the vehicle 10 to travel on, thus reducing the vehicle 10's passability. Therefore, in some environments, the angle between the vehicle's heading and the direction of its center of gravity velocity cannot be increased to the maximum right angle.

[0122] In one embodiment, the angle between the vehicle's heading and the direction of its center of gravity velocity can be controlled according to the road on which the vehicle 10 travels. Specifically, when the road on which the vehicle 10 travels has a first width, the angle between the vehicle's heading and the direction of its center of gravity velocity is controlled to be less than a first angle. When the road on which the vehicle 10 travels has a second width, less than the first width, the angle between the vehicle's heading and the direction of its center of gravity velocity is controlled to be less than a second angle, and the second angle is less than the first angle. Here, the "road width" in this embodiment can be the actual width of the road or the width of the area within the road that allows the vehicle 10 to travel smoothly.

[0123] When the road width on which vehicle 10 travels is the larger first width, the road allows wider vehicles 10 to pass. Therefore, the angle between the vehicle 10's heading and its center of gravity velocity direction can be controlled to be smaller than the larger first angle, thus fully utilizing the vehicle 10's anti-rollover capability. When the road width on which vehicle 10 travels is the smaller second width, only narrower vehicles 10 can pass. Therefore, the angle between the vehicle 10's heading and its center of gravity velocity direction can be controlled to be smaller than the smaller second angle, thus limiting the increase in the road width required for vehicle 10 and ensuring smooth turning of vehicle 10.

[0124] In one embodiment, after the vehicle body roll angle of the vehicle 10 increases to the first preset value and before the steering wheel begins to return to center, the steering controller 132 actively controls the steering angles of the front wheels 170 and the rear wheels 180. This allows the steering controller to increase the angle between the vehicle 10's heading and the direction of its center of gravity velocity, while simultaneously maintaining the vehicle 10's turning radius in different states depending on the control objective. For example, the steering controller 132 can increase the angle between the vehicle 10's heading and the direction of its center of gravity velocity while keeping the turning radius constant during steering; or, the steering controller 132 can increase the angle between the vehicle 10's heading and the direction of its center of gravity velocity while increasing the turning radius during steering.

[0125] The turning radius is the distance between the center of mass of vehicle 10 and the center of revolution when vehicle 10 is in revolution. During the turning process of vehicle 10, the magnitude of the centripetal force is determined by the turning radius. The larger the turning radius, the smaller the centripetal force, and the smaller the turning radius, the larger the centripetal force.

[0126] Therefore, when this embodiment increases the angle between the vehicle 10's frontal orientation and the direction of its center of gravity velocity while keeping the vehicle 10's turning radius constant, it can increase the vehicle 10's stabilizing torque while avoiding an increase in the roll torque, thus providing a strong guarantee for eliminating the risk of rollover. Furthermore, keeping the vehicle 10's turning radius constant during turning ensures that the vehicle 10 still conforms to the driver's steering intention before the steering wheel begins to return to center when the steering controller 132 actively controls it, thereby avoiding the driver's misjudgment that the vehicle 10 is out of control, reducing the probability of the driver over-controlling, and thus improving the safety of the vehicle 10.

[0127] If this application increases the angle between the vehicle 10's frontal orientation and the direction of its center of gravity velocity, and simultaneously increases the vehicle 10's turning radius, then while increasing the vehicle 10's stabilizing torque, it can reduce the roll torque by decreasing the centripetal force, thereby increasing the difference between the stabilizing torque and the roll torque, and promoting the elimination of roll risk for the vehicle 10.

[0128] The steering controller 132 determines the steering angles of the front wheels 170 and the rear wheels 180 in the following manner, thereby increasing the angle between the vehicle's heading and the direction of the center of gravity velocity while maintaining the vehicle's turning radius unchanged. Specifically, the steering controller 132 is connected to the controller of the Automated Driving System (ADS). The ADS controller first plans a motion path adapted to the steering wheel angle before the steering wheel begins to straighten. Then, the ADS controller sends the obtained motion path to the steering controller 132, enabling the steering controller 132 to determine the corresponding steering angles of the front wheels 170 and the rear wheels 180 based on the motion path sent by the ADS controller. Ultimately, by controlling the steering angles of the front wheels 170 and the rear wheels 180, the angle between the vehicle's heading and the direction of the center of gravity velocity is increased while maintaining the vehicle's turning radius unchanged.

[0129] Furthermore, the steering controller 132 determines the steering angles of the front wheels 170 and the rear wheels 180 in order to increase the angle between the vehicle's heading and the direction of the center of gravity velocity and increase the turning radius of the vehicle 10. The specific method for this is described above and will not be repeated here.

[0130] When the steering controller 132 increases the angle between the vehicle 10's frontal orientation and the direction of its center of gravity velocity to reduce the risk of vehicle 10 rollover, and the turning radius increases during the turning process, the steering controller 132 can, after the vehicle 10's body roll angle increases to the first preset value, and before the steering wheel begins to return to center, and when there are no obstacles in the vehicle 10's forward direction, actively control the steering angles of the front wheels 170 and rear wheels 180 of the vehicle 10 to increase the angle between the vehicle 10's frontal orientation and the direction of its center of gravity velocity, and to increase the vehicle 10's turning radius during the turning process. If there are obstacles in the vehicle 10's forward direction, the active control of the steering angles of the front wheels 170 and rear wheels 180 is stopped, and the front wheels 170 and rear wheels 180 turn with the rotation of the steering wheel.

[0131] In this embodiment, the "direction of travel" can be the direction of travel of vehicle 10 before the steering controller 132 actively controls the steering angles of the front wheels 170 and the rear wheels 180, or it can be the direction of travel of vehicle 10 after the steering controller 132 actively controls the steering angles of the front wheels 170 and the rear wheels 180. Taking the direction of travel of vehicle 10 before the steering controller 132 actively controls the steering angles of the front wheels 170 and the rear wheels 180 as an example, the implementation process of this embodiment is illustrated as follows: The controller of the autonomous driving system can first determine the direction of travel of vehicle 10 before active control based on the steering angles of the front wheels 170 and the rear wheels 180. Then, it can use the vision or radar sensors of the autonomous driving system to detect whether there are obstacles in the direction of travel of vehicle 10 before active control. Finally, it can send the detection results to the steering controller 132, so that the steering controller 132 can control the front wheels 170 and the rear wheels 180 based on the detection results of the autonomous driving system.

[0132] While increasing its turning radius, vehicle 10 also changes its travel path. When the travel path of vehicle 10 changes, if there is an obstacle in the direction of travel, the driver will inevitably panic and jerk the steering wheel, leading to loss of control of vehicle 10. Therefore, in this embodiment, before increasing the turning radius of vehicle 10 during the turning process, it determines whether there is an obstacle in the direction of travel. Only when there is no obstacle in the direction of travel will the steering angles of the front wheels 170 and the rear wheels 180 be actively controlled, thereby preventing vehicle 10 from losing control due to driver operation and improving the safety of vehicle 10.

[0133] In addition to reducing the risk of vehicle 10 roll through the steering system 130, the anti-roll capability of vehicle 10 can also be improved by combining the steering system 130 with one or more of the braking system 120 and suspension system 140. The following is a detailed introduction to the method of coordinating multiple anti-roll systems, using the steering system 130 combined with the braking system 120 and suspension system 140 as an example:

[0134] refer to Figure 8 The diagram shown is a control timing diagram for a vehicle. Figure 8 In the process of increasing the body roll angle of vehicle 10, it sequentially increases from a third preset value, then a second preset value, and finally a first preset value. For example, the first, second, and third preset values ​​can be pre-set fixed values; for instance, the first preset value can be 15°, 16°, or 17°, the second preset value can be 12°, 13°, or 14°, and the third preset value can be 8°, 9°, or 10°. The first, second, and third preset values ​​can also be determined in real time based on the longitudinal and lateral accelerations and body height of vehicle 10; for example, the first, second, and third preset values ​​decrease as the longitudinal and lateral accelerations and body height of vehicle 10 increase.

[0135] After the body roll angle of vehicle 10 increases from zero to a third preset value, the anti-rollover function is not enabled in the suspension system 140, braking system 120, and steering system 130. At this time, the actuator 141 of the suspension system 140 outputs the first braking force, the braking torque output by the brake motor 121 of the braking system 120 is zero, and the front wheels 170 and rear wheels 180 of the steering system 130 rotate with the rotation of the steering wheel.

[0136] As the vehicle body roll angle increases, after the roll angle increases to the third preset value but before it increases to the second preset value, the suspension system 140 begins to activate its anti-rollover function. At this time, the actuator 141 of the suspension system 140 outputs the second braking force, the brake motor 121 of the braking system 120 outputs zero braking torque, and the front wheels 170 and rear wheels 180 of the steering system 130 rotate with the rotation of the steering wheel.

[0137] After the suspension system 140 outputs the second working force, the suspension stiffness of the vehicle 10 is increased compared to the suspension stiffness when the actuator 141 outputs the first working force. Greater suspension stiffness allows the vehicle 10 to produce a smaller body roll angle under the same lateral force, thereby reducing the lateral offset of the vehicle 10's center of gravity. Since the lateral offset of the center of gravity leads to a shortening of the stabilizer arm, this embodiment reduces the amount of stabilizer arm shortening by increasing the suspension stiffness, thereby preventing excessive reduction in the stabilizing torque and ensuring the vehicle 10's rollover prevention capability.

[0138] In one embodiment, the suspension controller 142 can control the second actuation force output by the actuator 141 to increase as the suspension height of the vehicle 10 increases.

[0139] With the same body roll angle, the higher the suspension height of vehicle 10, the greater the lateral offset of the center of gravity. This embodiment controls the second action force to increase with the increase of suspension height, so that the body roll angle generated by vehicle 10 with a higher suspension height is smaller, thereby avoiding excessive reduction of the stabilizing arm of vehicle 10 with a high suspension height, and reducing the risk of vehicle 10 rolling over.

[0140] After the actuator 141 of the suspension system 140 outputs the second working force, if the vehicle body roll angle continues to increase, then after the vehicle body roll angle increases to the second preset value but before it increases to the first preset value, based on the suspension system 140 enabling its anti-rollover function, the braking system 120 is further controlled to enable its anti-rollover function. At this time, the actuator 141 of the suspension system 140 outputs the second working force, the braking torque output by the brake motor 121 of the braking system 120 increases from zero, and the front wheels 170 and rear wheels 180 of the steering system 130 rotate with the rotation of the steering wheel.

[0141] The magnitude of the centripetal force of vehicle 10 during cornering varies with its speed; the higher the speed, the greater the centripetal force, and vice versa. When the suspension system 140 outputs a second braking force, but the body roll angle continues to increase, it indicates that the suspension system 140's ability to suppress roll is insufficient. In this case, increasing the braking torque of vehicle 10 from zero reduces its speed, thereby decreasing the centripetal force and, consequently, the roll moment. The reduction in roll moment relatively increases vehicle 10's ability to suppress roll, ultimately achieving roll suppression.

[0142] In one embodiment, after the vehicle body roll angle of the vehicle 10 increases to a second preset value, the brake controller 122 can control the rate of increase of the braking torque to increase as the rate of increase of the vehicle body roll angle increases.

[0143] The greater the rate of increase in the vehicle body roll angle, the greater the gap between the actual roll suppression capability of the vehicle 10 and the required roll suppression capability. Therefore, in order to further ensure the roll suppression effect, this embodiment controls the rate of increase of the braking torque to increase with the rate of increase of the vehicle body roll, so that the vehicle 10 can adaptively adjust the roll suppression force according to the current situation, making the force of control intervention match the urgency of roll suppression, and making the dynamic movement of the vehicle 10 smoother.

[0144] After the actuator 141 of the suspension system 140 outputs the second working force and the braking torque of the braking system 120 increases from zero, if the vehicle body roll angle continues to increase, then after the vehicle body roll angle increases to the first preset value, before the steering wheel begins to return to center, based on the anti-rollover function of the suspension system 140 and the braking system 120, the steering system 130 is further controlled to enable its rollover function. At this time, the actuator 141 of the suspension system 140 outputs the second working force, the braking torque output by the brake motor 121 of the braking system 120 increases from zero, and the steering controller 132 actively controls the steering angle of the front wheels 170 and the rear wheels 180 of the vehicle 10 to increase the angle between the vehicle 10's heading and the direction of its center of gravity velocity.

[0145] After the body roll angle of vehicle 10 increases to a first preset value, if the steering wheel begins to return to center, it indicates that the roll risk has been eliminated through previous control. Thus, after the steering wheel begins to return to center, the steering angle of the front wheels 170 or the rear wheels 180 of vehicle 10 can be actively controlled to reduce the angle between the vehicle's heading and the direction of its center of gravity velocity. For example, when vehicle 10 turns left, the steering angle of the front wheels 170 to the left can be reduced after the steering wheel returns to center; when vehicle 10 turns right, the steering angle of the front wheels 170 to the right can be reduced after the steering wheel returns to center.

[0146] Because the angle between the vehicle's heading and the direction of its center of gravity velocity reduces its passability, increasing this angle before the steering wheel begins to straighten, while reducing the risk of rollover, also negatively impacts the vehicle's driving performance. Therefore, this embodiment, after the rollover risk is eliminated, further controls the reduction of the angle between the vehicle's heading and the direction of its center of gravity velocity. This reduces the required road width for the vehicle, restoring its passability to normal levels and ensuring smooth driving.

[0147] Once the steering wheel begins to return to center, the risk of roll has been eliminated. Therefore, in one embodiment, the actuator 141 of the suspension system 140 can be controlled to re-output the first braking force, and the braking torque output by the braking system 120 can be controlled to begin to decrease until it decreases to zero, thereby restoring the suspension system 140 and the braking system 120 to the state before the risk of roll occurred.

[0148] Next, refer to Figure 9 The flowchart shown illustrates a vehicle control method. The specific steps of the vehicle 10 coordinating the braking system 120, suspension system 140, and steering system 130 to suppress vehicle roll are as follows:

[0149] Step S101: Obtain the body roll angle of vehicle 10.

[0150] Step S102: Determine whether the vehicle body roll angle has increased to the third preset value.

[0151] If the vehicle body roll angle increases to the third preset value, then proceed from step S102 to step S103.

[0152] If the vehicle body roll angle does not increase to the third preset value, then proceed from step S102 to step S104.

[0153] In step S103, the actuator 141 of the suspension system 140 is controlled to output a second braking force, the braking torque of the vehicle 10 is controlled to be zero, and the front wheels 170 and the rear wheels 180 are controlled to rotate with the steering wheel.

[0154] After step S103 is completed, proceed to step S105.

[0155] In step S104, the actuator 141 of the control suspension system 140 outputs the first braking force, controls the braking torque of the vehicle 10 to be zero, and controls the front wheel 170 and the rear wheel 180 to rotate with the steering wheel.

[0156] After step S104 is completed, it can be done as follows: Figure 9 The process can return to step S101, or end the current control flow (not shown in the attached diagram).

[0157] Step S105: Determine whether the vehicle body roll angle has increased to the second preset value.

[0158] If the vehicle body roll angle increases to the second preset value, then proceed from step S105 to step S106.

[0159] If the vehicle body roll angle does not increase to the second preset value, then proceed from step S105 back to step S103.

[0160] In step S106, the actuator 141 of the control suspension system 140 outputs a second braking force, controls the braking torque of the vehicle 10 to increase from zero, and controls the front wheels 170 and rear wheels 180 to rotate with the steering wheel.

[0161] After step S106 is completed, proceed to step S107.

[0162] Step S107: Determine whether the vehicle body roll angle has increased to the first preset value.

[0163] If the vehicle body roll angle increases to the first preset value, then proceed from step S107 to step S108.

[0164] If the vehicle body roll angle does not increase to the first preset value, then proceed from step S107 back to step S106.

[0165] In step S108, the actuator 141 of the control suspension system 140 outputs a second braking force, controls the braking torque of the vehicle 10 to increase from zero, and actively controls the steering angle of the front wheel 170 and the rear wheel 180 to increase the angle between the vehicle 10's frontal orientation and the center of gravity velocity direction.

[0166] After step S108 is completed, proceed to step S109.

[0167] Step S109: Determine if the steering wheel has started to return to center.

[0168] If the steering wheel begins to straighten, proceed to step S110.

[0169] If the steering wheel does not begin to return to center, return to step S108.

[0170] In step S110, the actuator 141 of the suspension system 140 is controlled to output the first braking force, and the braking torque output by the braking system 120 is controlled to begin to decrease until it decreases to zero. The steering angle of the front wheel 170 or the rear wheel 180 of the vehicle 10 is actively controlled to reduce the angle between the vehicle 10's frontal orientation and the direction of its center of gravity velocity.

[0171] After step S110 is completed, the current control flow ends.

[0172] In addition to the above-mentioned method of preventing vehicle 10 from rolling over by simultaneously combining suspension system 140, braking system 120 and steering system 130, vehicle 10 can also be prevented from rolling over by combining only suspension system 140 and steering system 130, or only braking system 120 and steering system 130.

[0173] The specific method for preventing vehicle 10 from rolling over by combining only the suspension system 140 and the steering system 130 can be as follows: After the body roll angle of vehicle 10 increases from zero to a third preset value, the actuator 141 of the suspension system 140 is controlled to output a first working force, and the front wheels 170 and rear wheels 180 of the steering system 130 rotate with the steering wheel. After the body roll angle of vehicle 10 increases to the third preset value but before it increases to the first preset value, the actuator 141 of the suspension system 140 is controlled to output a second working force, and the front wheels 170 and rear wheels 180 of the steering system 130 rotate with the steering wheel. After the body roll angle of vehicle 10 increases to the first preset value but before the steering wheel begins to return to center, the actuator 141 of the suspension system 140 is controlled to output a second working force, and the steering angle of the front wheels 170 and rear wheels 180 of vehicle 10 is actively controlled to increase the angle between the vehicle 10's frontal orientation and the direction of its center of gravity velocity. After the steering wheel begins to return to center, the actuator 141 of the control suspension system 140 outputs the first working force and actively controls the steering angle of the front wheels 170 and the rear wheels 180 of the vehicle 10 to reduce the angle between the vehicle 10's heading and the direction of its center of gravity velocity.

[0174] The specific method for preventing vehicle 10 from rolling over by combining only the braking system 120 and the steering system 130 can be as follows: After the vehicle 10's body roll angle increases from zero but before it reaches a second preset value, the braking torque output by the braking system 120 is controlled to be zero, and the front wheels 170 and rear wheels 180 of the steering system 130 rotate with the steering wheel. After the vehicle 10's body roll angle increases to the second preset value but before it reaches the first preset value, the braking torque output by the braking system 120 is controlled to increase from zero, and the front wheels 170 and rear wheels 180 of the steering system 130 rotate with the steering wheel. After the vehicle 10's body roll angle increases to the first preset value but before the steering wheel begins to return to center, the braking torque output by the braking system 120 is controlled to increase from zero, and the steering angles of the front wheels 170 and rear wheels 180 of the vehicle 10 are actively controlled to increase the angle between the vehicle 10's frontal orientation and the direction of its center of gravity velocity. After the steering wheel begins to return to center, the braking torque output by the control braking system 120 begins to decrease, and the steering angle of the front wheels 170 and rear wheels 180 of the vehicle 10 is actively controlled to reduce the angle between the vehicle 10's heading and the direction of its center of gravity velocity.

[0175] In this embodiment of the application, a controller for a vehicle 10 is also provided, and the control method executed by the controller is the same as described above. Figures 1-9 The control functions implemented by the relevant control methods correspond to the control functions.

[0176] For example, when the braking system 120, steering system 130, and suspension system 140 are integrated in a corner module, the controller of this embodiment may include a corner module controller. When the braking system 120, steering system 130, and suspension system 140 are not integrated, the controller of this embodiment may include a steering controller 132 for the steering system 130, a brake controller 122 for the braking system 120, and a suspension controller 142 for the suspension system 140. Furthermore, when it comes to control at the vehicle-wide level of the vehicle 10, the controller of this embodiment may also include a vehicle controller 160.

[0177] Specifically, the controller is used for:

[0178] During the turning process of vehicle 10, before the body roll angle of vehicle 10 increases to a first preset value, the front wheels 170 and rear wheels 180 of vehicle 10 are controlled to turn with the steering wheel of vehicle 10. After the body roll angle of vehicle 10 increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front wheels 170 and rear wheels 180 of vehicle 10 is actively controlled to increase the angle between the vehicle's heading and the direction of its center of gravity velocity.

[0179] The controller can also be used to: actively control the steering angle of the front wheels 170 or the rear wheels 180 of the vehicle 10 after the steering wheel begins to return to center, so as to reduce the angle between the vehicle 10’s heading and the direction of its center of gravity velocity.

[0180] The controller can also be used to: after the body roll angle of the vehicle 10 increases to a first preset value, before the steering wheel begins to return to center, actively control the steering angle of the front wheels 170 and the rear wheels 180 of the vehicle 10 so that the angle between the vehicle 10's heading and the center of gravity velocity direction increases to the point where the vehicle 10's heading is perpendicular to the center of gravity velocity direction.

[0181] The controller can also be used to: after the body roll angle of the vehicle 10 increases to the first preset angle preset value, before the steering wheel begins to return to center, actively control the front wheels 170 to turn to the left and control the rear wheels 180 to turn to the right during a left turn.

[0182] The controller can also be used to: after the body roll angle of the vehicle 10 increases to a first preset value, before the steering wheel begins to return to center, actively control the steering angle of the front wheels 170 and the rear wheels 180 of the vehicle 10 so that the angle between the vehicle 10's frontal orientation and the direction of the center of gravity velocity increases and the vehicle 10's turning radius remains unchanged during the turning process.

[0183] The controller can also be used to: after the body roll angle of the vehicle 10 increases to a first preset value, before the steering wheel begins to return to center, actively control the steering angle of the front wheels 170 and the rear wheels 180 of the vehicle 10 so that the angle between the vehicle 10's frontal orientation and the direction of the center of gravity velocity increases and the turning radius of the vehicle 10 increases during the turning process.

[0184] The controller can also be used to: after the body roll angle of the vehicle 10 increases to a first preset value, before the steering wheel begins to return to center, and when there are no obstacles in the forward direction of the vehicle 10, actively control the steering angle of the front wheels 170 and the rear wheels 180 of the vehicle 10 so that the angle between the vehicle 10's frontal orientation and the direction of the center of gravity velocity increases and the turning radius of the vehicle 10 increases during the turning process.

[0185] The controller can also be used to: when the road on which vehicle 10 is traveling is of a first width, control the angle between the heading of vehicle 10 and the velocity direction of its center of gravity to be less than a first angle. When the road on which vehicle 10 is traveling is of a second width less than the first width, control the angle between the heading of vehicle 10 and the velocity direction of its center of gravity to be less than a second angle, and the second angle is less than the first angle.

[0186] The controller can also be used to: control the braking torque of vehicle 10 to be zero before the vehicle body roll angle of vehicle 10 increases to a second preset value, where the second preset value is less than a first preset value; and control the braking torque of vehicle 10 to increase from zero after the vehicle body roll angle of vehicle 10 increases to the second preset value.

[0187] The controller can also be used to: after the body roll angle of the vehicle 10 increases to a second preset value, control the rate of increase of the braking torque to increase as the rate of increase of the body roll angle increases.

[0188] The controller can also be used to: control the actuator 141 of the suspension system 140 to output a first working force before the body roll angle of the vehicle 10 increases to a third preset value, wherein the third preset value is less than the first preset value; and control the actuator 141 of the suspension system 140 to output a second working force after the body roll angle of the vehicle 10 increases to the third preset value, wherein the second working force is greater than the first working force.

[0189] The controller can also be used to control the second actuation force output by the actuator 141 to increase as the suspension height of the vehicle 10 increases after the body roll angle of the vehicle 10 increases to a third preset value.

[0190] In this embodiment of the application, an electric vehicle is also provided. The electric vehicle includes a corner module and a controller. The corner module is used to drive the front wheel and the right front wheel of the electric vehicle to rotate, respectively. The control method executed by the controller is the same as described above. Figures 1-9The control functions implemented by the relevant control methods correspond to the control functions. In one embodiment, there may be four corner modules, which are used to drive the left front wheel, right front wheel, left rear wheel and right rear wheel of the electric vehicle, respectively.

[0191] For more detailed information on controllers and electric vehicles, please refer to the previous text. Figures 1-9 An introduction to the control methods of electric vehicles.

[0192] In the embodiments of this application, the words "exemplary," "for example," etc., are used to indicate that they are examples, illustrations, or descriptions. Any embodiment or design that is described as "exemplary" in this application should not be construed as being more preferred or advantageous than other embodiments or design options. Specifically, the use of the term "exemplary" is intended to present the concept in a concrete manner.

[0193] It should be understood that the term "embodiment" used throughout this specification means that a specific feature, structure, or characteristic related to an embodiment is included in at least one embodiment of this application. Therefore, various embodiments throughout this specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0194] It should also be understood that in this application, "when," "if," "in the circumstances of," and "if" all refer to a situation where a corresponding action will be taken under certain objective circumstances, and are not time-limited. They do not require the device to perform a judgment action, nor do they imply any other limitations. Furthermore, in this application, the descriptions of conditions such as "when," "if," "in the circumstances of," and "if" can be understood as necessary conditions, without limiting whether the condition is a sufficient condition or a necessary and sufficient condition. For example, "in the case of A, execute B" can be understood as "if at least A is satisfied, execute B."

[0195] 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 in that, The control method is used to control the direction of the electric vehicle's front end during turning to prevent the electric vehicle from overturning. The control method includes: During the turning process of the electric vehicle, before the body roll angle of the electric vehicle increases to a first preset value, the front wheels and rear wheels of the electric vehicle are controlled to rotate with the rotation of the steering wheel of the electric vehicle. After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled to increase the angle between the direction of the electric vehicle's front and the direction of its center of gravity velocity.

2. The control method according to claim 1, characterized in that, The control method further includes: After the steering wheel begins to return to center, the steering angle of the front or rear wheels of the electric vehicle is actively controlled to reduce the angle between the direction of the electric vehicle's front and the direction of its center of gravity velocity.

3. The control method according to claim 1, characterized in that, The control method further includes: After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled so that the angle between the vehicle's heading and the center of gravity velocity direction increases to the point where the vehicle's heading is perpendicular to the center of gravity velocity direction.

4. The control method according to claim 1, characterized in that, The control method further includes: After the body roll angle of the electric vehicle increases to the first preset angle preset value, before the steering wheel begins to return to center, the front wheels are actively controlled to turn to the left and the rear wheels are controlled to turn to the right during the left turn.

5. The control method according to claim 1, characterized in that, The control method further includes: After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled so that the angle between the direction of the electric vehicle's front and the direction of the center of gravity velocity increases and the turning radius of the electric vehicle remains unchanged during the turning process.

6. The control method according to claim 1, characterized in that, The control method further includes: After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled to increase the angle between the direction of the electric vehicle's front and the direction of its center of gravity velocity, and the turning radius of the electric vehicle increases during the turning process.

7. The control method according to claim 6, characterized in that, The control method further includes: After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, and when there are no obstacles in the forward direction of the electric vehicle, the steering angles of the front and rear wheels of the electric vehicle are actively controlled to increase the angle between the vehicle's front-facing direction and the direction of its center of gravity velocity, and the turning radius of the electric vehicle increases during the turning process.

8. The control method according to claim 1, characterized in that, The control method further includes: When the road on which the electric vehicle travels is of a first width, the angle between the direction of the electric vehicle's front and the direction of its center of gravity velocity is less than a first angle. When the road on which the electric vehicle travels is a second width that is less than the first width, the angle between the direction the electric vehicle faces and the direction of its center of gravity velocity is less than the second angle, and the second angle is less than the first angle.

9. The control method according to claim 1, characterized in that, The control method further includes: Before the body roll angle of the electric vehicle increases to a second preset value, the braking torque of the electric vehicle is controlled to be zero, where the second preset value is less than the first preset value. After the body roll angle of the electric vehicle increases to a second preset value, the braking torque of the electric vehicle is controlled to increase from zero.

10. The control method according to claim 9, characterized in that, The control method further includes: After the body roll angle of the electric vehicle increases to a second preset value, the rate of increase of the braking torque is controlled to increase as the rate of increase of the body roll angle increases.

11. The control method according to any one of claims 1 to 10, characterized in that, The control method further includes: Before the body roll angle of the electric vehicle increases to a third preset value, the actuator of the control suspension system outputs a first action force, wherein the third preset value is less than the first preset value; After the body roll angle of the electric vehicle increases to the third preset value, the actuator of the suspension system is controlled to output a second working force, which is greater than the first working force.

12. The control method according to claim 11, characterized in that, The control method further includes: After the body roll angle of the electric vehicle increases to the third preset value, the second actuation force output by the actuator increases as the suspension height of the electric vehicle increases.

13. A controller for an electric vehicle, characterized in that, The controller is used for: During the turning process of the electric vehicle, before the body roll angle of the electric vehicle increases to a first preset value, the front wheels and rear wheels of the electric vehicle are controlled to rotate with the rotation of the steering wheel of the electric vehicle. After the body roll angle of the electric vehicle increases to the first preset value, before the steering wheel begins to return to center, the steering angle of the front and rear wheels of the electric vehicle is actively controlled to increase the angle between the direction of the electric vehicle's front and the direction of its center of gravity velocity.

14. The controller according to claim 13, characterized in that, The controller is also used for: After the steering wheel begins to return to center, the steering angle of the front or rear wheels of the electric vehicle is actively controlled to reduce the angle between the direction of the electric vehicle's front and the direction of its center of gravity velocity.

15. An electric vehicle, characterized in that, The electric vehicle includes a corner module and a controller. The corner module is used to drive the front and rear wheels of the electric vehicle to rotate, and the controller is used to execute the control method of the electric vehicle as described in any one of claims 1-12.

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