A vehicle drift control method and device, vehicle and medium

Abstract

Embodiments of the present application provide a vehicle drift control method and device, a vehicle and a medium. The method comprises: when the vehicle needs to drift, determining a vehicle torque and a rear wheel steering angle corresponding to vehicle drift driving, and controlling the vehicle to drift according to the vehicle torque and the rear wheel steering angle. By controlling the rear wheel steering angle, the amplitude of vehicle drift can be adjusted, thereby reducing the energy consumption generated by vehicle drift driving.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to a vehicle drift control method, device, vehicle, and medium. Background Technology

[0002] Drifting refers to the process by which a driver controls a vehicle to slide sideways by oversteering, maintaining the vehicle on a rotating trajectory by controlling the steering wheel, accelerator, and brakes.

[0003] Drifting often relies on the driver's skill in maneuvering, such as their proficiency in coordinating the steering wheel, accelerator, and brakes. Because drifting typically requires braking the rear wheels or driving the rear wheels at speeds exceeding the vehicle's speed to cause them to lose traction and skid, braking the rear wheels converts a significant amount of kinetic energy into heat, while driving the rear wheels at speeds exceeding the vehicle's speed results in substantial kinetic energy loss. Therefore, current drift control methods result in significant energy consumption. Summary of the Invention

[0004] This application provides a vehicle drift control method, device, vehicle, and medium. By controlling the rear wheel steering, the energy consumption generated during vehicle drifting is reduced, and the stability of drifting is improved.

[0005] In a first aspect, embodiments of this application provide a vehicle drift control method, the method comprising:

[0006] When a vehicle needs to drift, determine the vehicle torque and rear wheel steering angle corresponding to the vehicle's drifting motion;

[0007] The vehicle is controlled to drift based on the vehicle torque and the rear wheel steering angle.

[0008] In the above method, vehicle drifting is controlled by adjusting vehicle torque and rear wheel steering angle. Compared with existing solutions that drift by braking the rear wheels or driving the rear wheels at speeds greater than the vehicle speed, this embodiment controls drifting through the coordination of vehicle torque and rear wheel steering angle. This fully utilizes the kinetic energy of the vehicle motor to adjust the drift amplitude. Torque distribution reduces energy consumption, decreases the load on the brake actuator, supports longer drift durations, and improves fuel economy. Controlling the vehicle to drift to a certain position via rear wheel steering requires less torque than solutions without rear wheel steering control, thus saving energy. Simultaneously, the drifting device does not require a large driving force, reducing its load.

[0009] In one alternative embodiment of the first aspect, the vehicle torque includes the front axle torque and / or the rear axle torque of the vehicle.

[0010] In one alternative embodiment of the first aspect, one or more of the front axle torque, the rear axle torque, and the rear wheel steering angle are determined based on the vehicle's steering parameters.

[0011] In the above method, the rear wheel speed can be controlled by distributing the torque between the front and rear axles, thereby causing the rear wheels to slip and achieve drifting. By controlling the steering of the rear wheels, the difficulty of drifting for the user is reduced, and the operability of vehicle drift control is improved.

[0012] In one alternative embodiment of the first aspect, the vehicle's steering parameters include the vehicle's current steering parameters and the vehicle's target steering parameters, wherein one or more of the front axle torque, the rear axle torque, and the rear wheel steering angle are determined based on the difference between the current steering parameters and the target steering parameters.

[0013] In the above method, controlling the front axle torque, rear axle torque, and rear wheel steering angle of the vehicle based on the current steering parameters and the target steering parameters can make the vehicle's driving state closer to the target state, thereby improving the safety of drifting.

[0014] In one alternative embodiment of the first aspect, the current steering parameters include the vehicle's current center of gravity yaw angle and / or the vehicle's current yaw rate, and the target steering parameters include the vehicle's target center of gravity yaw angle and / or the vehicle's target yaw rate.

[0015] In one alternative embodiment of the first aspect, the target steering parameter is determined based on the vehicle's driving parameters, which include one or more of the vehicle's speed, steering wheel angle, accelerator pedal depth, wheel speed, brake pedal depth, and the road surface adhesion coefficient of the road surface on which the vehicle is traveling.

[0016] In one alternative embodiment of the first aspect, during the drifting of the vehicle, when the current steering parameter is greater than the target steering parameter:

[0017] The front axle torque and the rear axle torque are determined by reducing the proportion of the rear axle torque in the total torque of the vehicle; and / or,

[0018] The steering direction corresponding to the rear wheel steering angle is set to the opposite direction of the front wheel steering direction, which is determined based on the steering wheel direction of the vehicle.

[0019] In the above method, by reducing the proportion of rear axle torque in the vehicle's total torque and using the opposite direction of the front wheel steering direction as the direction of the rear wheel steering angle, the drift amplitude of the vehicle can be reduced to some extent. This improves the stability and safety of the vehicle during drifting and increases the drift distance. It also allows for more flexible utilization of vehicle performance, enabling drifting under more conditions.

[0020] In one alternative embodiment of the first aspect, during the drifting of the vehicle, when the current steering parameter is less than the target steering parameter:

[0021] The front axle torque and the rear axle torque are determined by increasing the proportion of the rear axle torque in the total torque of the vehicle; and / or,

[0022] The steering direction corresponding to the rear wheel steering angle is set as the front wheel steering direction, which is determined based on the steering wheel direction of the vehicle.

[0023] In the above method, by increasing the proportion of rear axle torque in the vehicle's total torque and using the front wheel steering direction as the rear wheel steering angle, the vehicle's drift amplitude can be increased to some extent. This improves the stability and safety of the vehicle during drifting, and increases the drift distance. It also allows for more flexible utilization of vehicle performance, enabling drifting under more conditions.

[0024] In one alternative embodiment of the first aspect, the rear axle torque includes a first rear wheel torque and a second rear wheel torque of the vehicle, wherein the first rear wheel torque is used to determine a first rear wheel speed of the first rear wheel, and the second rear wheel torque is used to determine a second rear wheel speed of the second rear wheel.

[0025] In the above method, the torque of the first rear wheel and the torque of the second rear wheel are determined based on the rear axle torque. Compared with the existing solution that controls vehicle drifting solely based on the rear axle torque, this embodiment controls the first and second rear wheels separately. This makes the control result more consistent with actual vehicle conditions and improves the overall drifting performance of the vehicle.

[0026] In one alternative of the first aspect, when there is a first wheel speed difference between the first rear wheel speed and the second rear wheel speed, the first rear wheel torque and the second rear wheel torque are determined based on the first wheel speed difference to reduce the distribution ratio of the target rear wheel torque in the rear axle torque, and the rear wheel corresponding to the target rear wheel torque is the rear wheel with the larger wheel speed among the first rear wheel and the second rear wheel.

[0027] In the above method, since rear wheel torque can be used to determine the rear wheel speed, the vehicle can adjust the rear wheel speed by adjusting the rear wheel torque. When there is a speed difference between the first and second rear wheels, reducing the torque of the rear wheel with the higher speed can reduce its speed, making the wheel speeds of the first and second rear wheels essentially the same. Compared to existing solutions that brake the rear wheel with the higher speed, this embodiment reduces the torque of the rear wheel with the higher speed instead of directly braking it. Reducing torque is equivalent to reducing energy consumption and also reducing the load on the braking device in the vehicle, supporting longer drifting periods. In existing solutions, during the braking of the rear wheel with the higher speed, some kinetic energy is converted into heat energy, causing energy loss. Therefore, this embodiment improves fuel economy and drift stability.

[0028] In one alternative embodiment of the first aspect, the front axle torque includes a first front wheel torque and a second front wheel torque of the vehicle, wherein the first front wheel torque is used to determine a first front wheel speed of the first front wheel of the vehicle, and the second front wheel torque is used to determine a second front wheel speed of the second front wheel of the vehicle.

[0029] In one alternative of the first aspect, when there is a second wheel speed difference between the first front wheel speed and the second front wheel speed, the first front wheel torque and the second front wheel torque are determined based on the second wheel speed difference to reduce the distribution ratio of the target front wheel torque in the front axle torque, and the front wheel corresponding to the target front wheel torque is the front wheel with the larger wheel speed between the first front wheel and the second front wheel.

[0030] In the above method, since the front wheel torque can be used to determine the front wheel speed, the vehicle can adjust the front wheel speed by adjusting the front wheel torque. When there is a wheel speed difference between the first and second front wheels, by reducing the torque of the front wheel with the higher wheel speed, the wheel speed of that front wheel can be reduced, making the wheel speed of the first and second front wheels essentially the same.

[0031] In one alternative embodiment of the first aspect, during the initial stage of the vehicle's drift, the steering direction corresponding to the rear wheel steering angle is set to the opposite direction of the front wheel steering direction; and / or,

[0032] At the end of the vehicle's drift phase, the steering direction corresponding to the rear wheel steering angle is set to the front wheel steering direction;

[0033] The direction of front wheel steering is determined based on the direction of the vehicle's steering wheel.

[0034] In the above method, reversing the front and rear wheels during the final stage of the drift increases the vehicle's fishtail amplitude, helping it quickly enter a drift state. Conversely, reversing the front and rear wheels during the final stage of the drift reduces the fishtail amplitude, helping the vehicle straighten and thus ending the drift.

[0035] In one alternative embodiment of the first aspect, the operation of controlling the vehicle to drift based on the vehicle torque and the rear wheel steering angle is performed only when the vehicle's driving condition meets preset driving condition conditions;

[0036] The preset driving conditions include: the vehicle speed is within a preset speed range, and / or the road surface adhesion coefficient of the road surface on which the vehicle travels is within a preset adhesion coefficient range.

[0037] In the above method, the drifting operation is only performed when the vehicle's driving conditions meet the preset driving conditions, thus ensuring the safety of vehicle drifting.

[0038] Secondly, embodiments of this application provide an electronic device, the device comprising:

[0039] The determining unit is used to determine the vehicle torque and rear wheel steering angle corresponding to the vehicle's drifting motion when the vehicle needs to drift.

[0040] The processing unit is used to control the vehicle to drift based on the vehicle torque and the rear wheel steering angle.

[0041] In one alternative embodiment of the second aspect, the vehicle torque includes the front axle torque and / or the rear axle torque of the vehicle.

[0042] In one alternative embodiment of the second aspect, one or more of the front axle torque, the rear axle torque, and the rear wheel steering angle are determined based on the vehicle's steering parameters.

[0043] In one alternative embodiment of the second aspect, the vehicle's steering parameters include the vehicle's current steering parameters and the vehicle's target steering parameters, wherein one or more of the front axle torque, the rear axle torque, and the rear wheel steering angle are determined based on the difference between the current steering parameters and the target steering parameters.

[0044] In one alternative embodiment of the second aspect, the current steering parameters include the vehicle's current center of gravity yaw angle and / or the vehicle's current yaw rate, and the target steering parameters include the vehicle's target center of gravity yaw angle and / or the vehicle's target yaw rate.

[0045] In one alternative embodiment of the second aspect, the target steering parameter is determined based on the vehicle's driving parameters, which include one or more of the vehicle's speed, steering wheel angle, accelerator pedal depth, wheel speed, brake pedal depth, and the road surface adhesion coefficient of the road surface on which the vehicle is traveling.

[0046] In an alternative embodiment of the second aspect, during the drifting of the vehicle, when the current steering parameter is greater than the target steering parameter:

[0047] The front axle torque and the rear axle torque are determined by reducing the proportion of the rear axle torque in the total torque of the vehicle; and / or,

[0048] The steering direction corresponding to the rear wheel steering angle is set to the opposite direction of the front wheel steering direction, which is determined based on the steering wheel direction of the vehicle.

[0049] In an alternative embodiment of the second aspect, during the drifting of the vehicle, when the current steering parameter is less than the target steering parameter:

[0050] The front axle torque and the rear axle torque are determined by increasing the proportion of the rear axle torque in the total torque of the vehicle; and / or,

[0051] The steering direction corresponding to the rear wheel steering angle is set as the front wheel steering direction, which is determined based on the steering wheel direction of the vehicle.

[0052] In one alternative embodiment of the second aspect, the rear axle torque includes a first rear wheel torque and a second rear wheel torque of the vehicle, wherein the first rear wheel torque is used to determine a first rear wheel speed of the first rear wheel, and the second rear wheel torque is used to determine a second rear wheel speed of the second rear wheel.

[0053] In one alternative embodiment of the second aspect, when there is a first wheel speed difference between the first rear wheel speed and the second rear wheel speed, the first rear wheel torque and the second rear wheel torque are determined based on the first wheel speed difference to reduce the distribution ratio of the target rear wheel torque in the rear axle torque, and the rear wheel corresponding to the target rear wheel torque is the rear wheel with the larger wheel speed among the first rear wheel and the second rear wheel.

[0054] In one alternative embodiment of the second aspect, the front axle torque includes a first front wheel torque and a second front wheel torque of the vehicle, wherein the first front wheel torque is used to determine a first front wheel speed of the first front wheel of the vehicle, and the second front wheel torque is used to determine a second front wheel speed of the second front wheel of the vehicle.

[0055] In an alternative embodiment of the second aspect, when there is a second wheel speed difference between the first front wheel speed and the second front wheel speed, the first front wheel torque and the second front wheel torque are determined based on the second wheel speed difference to reduce the distribution ratio of the target front wheel torque in the front axle torque, and the front wheel corresponding to the target front wheel torque is the front wheel with the larger wheel speed between the first front wheel and the second front wheel.

[0056] In an alternative embodiment of the second aspect, during the initial stage of the vehicle's drift, the steering direction corresponding to the rear wheel steering angle is set to the opposite direction of the front wheel steering direction; and / or,

[0057] At the end of the vehicle's drift phase, the steering direction corresponding to the rear wheel steering angle is set to the front wheel steering direction;

[0058] The direction of front wheel steering is determined based on the direction of the vehicle's steering wheel.

[0059] In an alternative embodiment of the second aspect, the operation of controlling the vehicle to drift based on the vehicle torque and the rear wheel steering angle is performed only when the vehicle's driving condition meets preset driving condition conditions;

[0060] The preset driving conditions include: the vehicle speed is within a preset speed range, and / or the road surface adhesion coefficient of the road surface on which the vehicle travels is within a preset adhesion coefficient range.

[0061] Thirdly, embodiments of this application provide an electronic device including a processor and a memory, the processor being coupled to the memory for storing a computer program, and the processor for calling and running the computer program, causing the electronic device to perform the method described in any of the preceding first aspects.

[0062] Fourthly, embodiments of this application provide a vehicle that includes the electronic devices described in the second or third aspect.

[0063] Fifthly, embodiments of this application provide a computer-readable storage medium storing a computer program that, when run on a computer or processor, implements the method described in any of the first aspects above.

[0064] The beneficial effects of the technical solutions provided in the second to fifth aspects of this application can be referred to the beneficial effects of the technical solutions in the first aspect, and will not be repeated here. Attached Figure Description

[0065] The accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0066] Figure 1 This is a schematic diagram of the architecture of a vehicle provided in an embodiment of this application;

[0067] Figure 2 This is a schematic flowchart of a vehicle drift control method provided in an embodiment of this application;

[0068] Figure 3 This is a schematic diagram of a vehicle drifting according to an embodiment of this application;

[0069] Figure 4 This is a schematic diagram of a U-shaped curve drift provided in an embodiment of this application;

[0070] Figure 5 This is a schematic diagram of an L-shaped curve drift provided in an embodiment of this application;

[0071] Figure 6 This is a schematic diagram of a fixed-circle drift provided in an embodiment of this application;

[0072] Figure 7 This is a schematic diagram of a figure-eight drift provided in an embodiment of this application;

[0073] Figure 8 This is a schematic flowchart of a drift control method provided in an embodiment of this application;

[0074] Figure 9 This is a schematic diagram of a drift control method provided in an embodiment of this application;

[0075] Figure 10 This is a functional unit block diagram of an electronic device provided in an embodiment of this application;

[0076] Figure 11 This is a schematic diagram of the structure of another electronic device provided in the embodiments of this application. Detailed Implementation

[0077] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0078] The terms "first," "second," "third," and "fourth," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or apparatus.

[0079] To facilitate understanding of the embodiments of this application, the specific technical problems to be solved by this application will be analyzed and proposed below.

[0080] Existing vehicle drifting techniques typically achieve this through rear-wheel slippage. Rear-wheel slippage occurs when the rear wheels lose traction or grip on the ground during driving. This causes the rear wheel speed to exceed the allowable range of friction between the tires and the ground, resulting in relative sliding between the rear wheels and the ground. Existing techniques primarily achieve rear-wheel slippage in the following ways:

[0081] Method 1: Negative speed difference between the rear wheels and the ground. Normally, the rear wheels of a vehicle should maintain a positive relative speed with the ground to ensure sufficient traction or grip for power and control. However, if the relative speed between the rear wheels and the ground is negative, it means the rear wheels are moving in the opposite direction to the vehicle's movement, which can lead to rear wheel slippage or loss of traction.

[0082] For example, a negative speed difference between the rear wheels and the ground can be achieved by the user pulling the handbrake, resulting in a relatively low rear wheel speed. Since the handbrake is typically used to brake the rear wheels, pulling the handbrake can lock the rear wheels. Locking up means that excessive braking causes the wheels to stop rotating and lock. Therefore, the locked rear wheels lose traction or grip with the ground, allowing the vehicle to drift. Although drifting can be achieved by pulling the handbrake, it also causes the vehicle to stop moving for a short time, making sustained drifting impossible. This method is commonly used for drifting front-wheel-drive vehicles and has relatively low hardware requirements.

[0083] Method 2: A positive speed difference exists between the rear wheels and the ground. A positive speed difference means that the rear wheels' speed relative to the ground is in the same direction as the vehicle's motion. In this case, the rear wheel speed is relatively high, thus ensuring the vehicle can drift a long distance.

[0084] For example, in rear-wheel drive or four-wheel drive vehicles, increasing the torque on the rear axle can generate more driving force for the rear wheels. This causes the rear wheels to spin, resulting in a drift. This method is commonly used in drifting rear-wheel drive or four-wheel drive vehicles and requires relatively high-performance vehicle hardware.

[0085] Method 3: Reduce the pressure between the rear wheels and the ground. Reducing the pressure between the rear wheels and the ground may decrease the traction and grip between the rear wheels and the ground, thus enabling the vehicle to drift.

[0086] For example, a user could slam on the brakes to reduce the pressure between the rear wheels and the ground. Slamming on the brakes causes the vehicle's weight to shift forward, placing most of the braking force on the front wheels, thus reducing the contact pressure on the rear wheels and causing them to slip. While slamming on the brakes can induce a drift, it also brings the vehicle to a stop for a short time, preventing sustained drifting and negatively impacting the driving experience.

[0087] As can be seen, methods 1 and 3 both involve rapidly braking to cause the rear wheels to slip, thus achieving a drift. However, braking a vehicle cannot achieve a long drift, and excessive braking may cause the vehicle to tilt or lose control, resulting in low safety.

[0088] Method 2 described above primarily achieves drifting by distributing torque between the front and rear axles to cause rear wheel slippage. However, while rear wheel slippage is a prerequisite for drifting, the vehicle requires coordinated control of the steering wheel, accelerator, and brakes to maintain the desired drift trajectory, demanding a high level of driving skill. Furthermore, the drift amplitude is influenced by various factors, making it difficult to achieve the desired drift trajectory solely through user input.

[0089] In view of this, this application provides a vehicle drift control method. When a vehicle needs to drift, the vehicle torque and rear wheel steering angle are determined based on the vehicle's steering parameters. The vehicle controls the front axle torque and rear axle torque according to the determined torque, causing the rear wheels to slip. Simultaneously, during the drift, the vehicle adjusts the drift amplitude by controlling the rear wheel steering angle. Therefore, by controlling the vehicle's drift based on the front axle torque, rear axle torque, and rear wheel steering angle, energy consumption is reduced. In addition to enabling long-distance drifts, this method also improves drift stability, reduces the difficulty of operation for the user, and allows the vehicle to drift along the user's desired trajectory.

[0090] The system architecture used in the embodiments of this application is described below. It should be noted that the system architecture and business scenarios described in this application are for the purpose of more clearly illustrating the technical solutions of this application, and do not constitute a limitation on the technical solutions provided in this application. As those skilled in the art will know, with the evolution of system architecture and the emergence of new business scenarios, the technical solutions provided in this application are also applicable to similar technical problems.

[0091] Please see Figure 1 , Figure 1 This is a schematic diagram of the architecture of a vehicle provided in an embodiment of this application. Figure 1 As shown, vehicle 10 includes motor 101. It is understood that... Figure 1The number and position of the motors shown are only one possible scenario, and this application embodiment does not limit this.

[0092] Vehicle 10 is either a rear-wheel drive vehicle or a four-wheel drive vehicle. For example, when vehicle 10 is a rear-wheel drive vehicle, it can be a front-engine rear-wheel drive vehicle, a mid-engine rear-wheel drive vehicle, or a rear-engine rear-wheel drive vehicle, etc. When vehicle 10 is a four-wheel drive vehicle, it can be a full-time four-wheel drive vehicle, a manually lockable four-wheel drive vehicle, an automatically lockable four-wheel drive vehicle, or an all-terrain four-wheel drive vehicle, etc.

[0093] Vehicle 10 can be a vehicle powered by electricity, a vehicle powered by gasoline, or a vehicle powered by a new energy hybrid powertrain. For example, when vehicle 10 is powered by electricity, it can be a new energy vehicle, such as a pure electric vehicle, a range-extended electric vehicle, a hybrid electric vehicle, or a fuel cell electric vehicle. When vehicle 10 is powered by gasoline, it can be a car, an agricultural transport vehicle, or a trailer. When vehicle 10 is a car, it can be a sedan, an SUV, a truck, a bus, or a van.

[0094] The electric motor 101 is typically the power source of the vehicle 10, and can be one or more of an internal combustion engine, an electric motor, or a hybrid system.

[0095] For example, when vehicle 10 includes three motors, one of the three motors is located on the front axle of vehicle 10, and the other two motors are located on the rear axle of vehicle 10. After vehicle 10 determines the front axle torque, rear axle torque, and rear wheel steering angle based on steering parameters, it can control the front wheel speed based on the front axle torque, control the rear wheel speed based on the rear axle torque, and control the rear wheel rotation based on the rear wheel steering angle through the three motors, thereby achieving control of drift driving.

[0096] For example, when vehicle 10 includes four motors, two of the four motors are located on the front axle of vehicle 10, respectively driving the first front wheel and the second front wheel. The other two motors are located on the rear axle of vehicle 10, respectively driving the first rear wheel and the second rear wheel. After vehicle 10 determines the torque of the first front wheel, the torque of the second front wheel, the torque of the first rear wheel, the torque of the second rear wheel, and the rear wheel steering angle based on steering parameters, it can control the wheel speed of the first front wheel based on the first front wheel torque, the wheel speed of the second front wheel based on the second front wheel torque, the wheel speed of the first rear wheel based on the first rear wheel torque, the wheel speed of the second rear wheel based on the second rear wheel torque, and the rotation of the rear wheels based on the rear wheel steering angle through the four motors, thereby achieving control of drift driving.

[0097] For example, when vehicle 10 includes dual rear axle motors, after determining the first rear wheel torque, the second rear wheel torque, and the rear wheel steering angle based on steering parameters, vehicle 10 can drive the first rear wheel according to the first rear wheel torque and drive the second rear wheel according to the second rear wheel torque using the dual rear axle motors. Vehicle 10 controls the rotation of the rear wheels according to the rear wheel steering angle, thereby achieving control for drift driving.

[0098] For example, when vehicle 10 includes front and rear dual motors, one motor is located on the front axle and the other on the rear axle. After determining the front axle torque, rear axle torque, and rear wheel steering angle based on steering parameters, vehicle 10 can drive the front wheels according to the front axle torque and the rear wheels according to the rear axle torque using the dual motors. Vehicle 10 controls the rear wheel rotation based on the rear wheel steering angle, thereby achieving control for drift driving.

[0099] For example, when vehicle 10 includes a rear axle single motor, after vehicle 10 determines the rear axle torque and rear wheel steering angle based on steering parameters, the rear wheels can be driven by the rear axle single motor according to the rear axle torque, and the vehicle can control the rear wheel rotation according to the rear wheel steering angle, thereby achieving control of drift driving.

[0100] In one implementation, when the rear axle of vehicle 10 includes two motors, such as dual-motor, triple-motor, or quad-motor systems, vehicle 10 can control the wheel speeds of the first and second rear wheels separately using the two motors on the rear axle. For example, when a first wheel speed difference exists between the first and second rear wheel speeds, vehicle 10 reduces the torque distribution ratio of the target rear wheel in the rear axle based on this first wheel speed difference, thereby determining the first and second rear wheel torques. The target rear wheel corresponds to the rear wheel with the higher wheel speed among the first and second rear wheels. Then, vehicle 10 drives the rear wheels using the two motors on the rear axle according to the determined first and second rear wheel torques, which can reduce the wheel speed difference between the first and second rear wheels and improve the drift stability of vehicle 10.

[0101] In one implementation, if the rear axle of vehicle 10 includes a motor, for example, vehicle 10 may include a single rear axle motor or dual front and rear motors. When there is a first wheel speed difference between the first rear wheel speed and the second rear wheel speed, vehicle 10 can reduce the wheel speed difference between the first and second rear wheels by braking the target rear wheel, thereby improving the drift stability of vehicle 10. The target rear wheel is the rear wheel with the higher wheel speed among the first and second rear wheels.

[0102] In one implementation, where the front axle of vehicle 10 includes two motors (e.g., vehicle 10 includes four motors), vehicle 10 can control the wheel speeds of the first and second front wheels using the two motors on the front axle. When a second wheel speed difference exists between the first and second front wheel speeds, vehicle 10 determines the first and second front wheel torques by reducing the torque distribution ratio of the target front wheel in the front axle based on this second wheel speed difference. The target front wheel corresponds to the front wheel with the higher wheel speed among the first and second front wheels. Then, vehicle 10 drives the front wheels using the two motors on the front axle according to the determined first and second front wheel torques, thereby reducing the wheel speed difference between the first and second front wheels and improving the drift stability of vehicle 10.

[0103] In one implementation, the front axle of vehicle 10 may include one motor or no motor; for example, vehicle 10 may include a single rear axle motor, two rear axle motors, three rear axle motors, or a combination of front and rear motors. When there is a first wheel speed difference between the first front wheel speed and the second front wheel speed, vehicle 10 can reduce the wheel speed difference between the first and second front wheels by braking the target front wheel, thereby improving the drift stability of vehicle 10. The target front wheel corresponds to the front wheel with the higher wheel speed among the first and second front wheels.

[0104] Please see Figure 2 , Figure 2 This is a flowchart illustrating a vehicle drift control method provided in an embodiment of this application. The method is applied to, for example... Figure 1 The vehicle shown. (As shown) Figure 2 As shown, the method includes, but is not limited to, the following steps:

[0105] Step S201: When the vehicle needs to drift, determine the vehicle torque and rear wheel steering angle corresponding to the vehicle drifting.

[0106] Specifically, a vehicle can drift by increasing the rear axle torque, causing the rear wheel speed to exceed the vehicle speed, thus inducing rear wheel slippage. Therefore, vehicle torque can be used to initiate a drift. When a vehicle needs to drift, it can first determine the required vehicle torque and rear wheel steering angle for drifting.

[0107] In one possible implementation, vehicle torque includes the front axle torque and / or the rear axle torque of the vehicle.

[0108] Specifically, when the vehicle includes a single rear axle motor or dual rear axle motors, the vehicle torque includes the rear axle torque. When the vehicle includes both a front axle motor and a rear axle motor, the vehicle torque includes both the front axle torque and the rear axle torque.

[0109] Specifically, the vehicle controls drifting by simultaneously controlling the magnitude of the front axle torque, the magnitude of the rear axle torque, and the direction and angle of the rear wheel steering angle. For example, by controlling the front and rear axle torques, the vehicle can cause the rear wheels to slip, thus achieving a drift. Simultaneously, by controlling the rear wheel steering angle, the vehicle can control the extent of its fishtailing during the drift. This improves the vehicle's drifting stability and allows it to follow the desired drift trajectory.

[0110] In one possible implementation, one or more of the front axle torque, rear axle torque, and rear wheel steering angle are determined based on the vehicle's steering parameters. These steering parameters include the vehicle's current steering parameters and its target steering parameters. The current steering parameters include the vehicle's current center of gravity yaw angle and / or its current yaw rate, while the target steering parameters include the vehicle's target center of gravity yaw angle and / or its target yaw rate.

[0111] In one possible implementation, the target steering parameters are determined based on the vehicle's driving parameters, which include one or more of the following: vehicle speed, steering wheel angle, accelerator pedal depth, wheel speed, brake pedal depth, and the road surface adhesion coefficient of the road surface on which the vehicle is traveling.

[0112] Specifically, vehicles can acquire driving parameters through one or more sensors installed on the vehicle. The vehicle can then determine its driving status in real time based on the acquired driving parameters, and thus perform drift control based on the driving status.

[0113] For example, driving parameters may include one or more of the following: vehicle speed, steering wheel angle, accelerator pedal depth, wheel speed, brake pedal depth, and the road surface adhesion coefficient. Among these, the steering wheel angle, accelerator pedal depth, and brake pedal depth can be user-controlled. The vehicle can determine whether the user has initiated a drift by steering based on the steering wheel angle, and also determine the user's desired drift amplitude. The accelerator pedal depth and / or brake pedal depth can be used to determine the vehicle's total torque, which in turn is used to determine the front axle torque and rear axle torque. Vehicle speed and wheel speed characterize the vehicle's current driving state.

[0114] The coefficient of friction (COP) is the ratio of friction between the tires and the road surface, and it is commonly used to measure a vehicle's grip under different road conditions. For example, a vehicle can assess the COP by monitoring wheel speed and steering angle, and then adopt corresponding drift control strategies.

[0115] Specifically, when the determined coefficient of friction is greater than the calibrated threshold, it indicates that the friction between the tires and the road surface is high, and the grip between the wheels and the ground is also high. Therefore, the vehicle can increase the torque distribution to the rear axle, allowing the rear wheels to generate more driving force to achieve drifting. When the estimated coefficient of friction is less than or equal to the calibrated threshold, it indicates that the friction between the tires and the road surface is low, and the grip between the wheels and the ground is also low. Therefore, the vehicle can achieve drifting without allocating a large amount of torque to the rear axle, saving energy.

[0116] Step S202: Control the vehicle to drift based on the vehicle torque and rear wheel steering angle.

[0117] Specifically, the vehicle controls its drifting by determining the front wheel speed based on the front axle torque, the rear wheel speed based on the rear axle torque, and the rear wheel steering angle.

[0118] The total torque output by the vehicle's electric motor and / or engine is called the vehicle torque, which includes the front axle torque and the rear axle torque. The vehicle torque can be determined based on the depth of the accelerator pedal. For example, a greater depth of the accelerator pedal indicates that the vehicle needs to output a larger driving force to make the wheels turn quickly, and the determined vehicle torque will also be relatively larger.

[0119] Since torque can be understood as the driving force that a vehicle outputs to the wheels, which can cause the wheels to rotate under a certain driving force, torque can also be used to determine the wheel speed. For example, front axle torque can be used to determine the front wheel speed, and rear axle torque can be used to determine the rear wheel speed. In one possible implementation, when the rear wheel speed is greater than the vehicle speed, the rear wheels slip, thus causing the vehicle to drift.

[0120] Furthermore, the rear wheel steering angle includes both the direction and magnitude of the rear wheel steering angle. The direction determines whether the rear wheels are turning left or right, while the magnitude determines the degree of rear wheel steering. Since drifting, also known as fishtailing, refers to the rear wheels losing traction, causing the rear of the vehicle to suddenly deviate from its original trajectory, resulting in a tail-swinging motion, controlling the rear wheel steering angle allows for better control of the fishtailing amplitude and direction, enhancing the vehicle's maneuverability and stability during drifting. In one possible implementation, the drifting operation based on vehicle torque and rear wheel steering angle is performed only when the vehicle's driving conditions meet preset driving condition conditions. These preset driving condition conditions include: the vehicle speed being within a preset speed range, and / or, the road surface adhesion coefficient being within a preset adhesion coefficient range.

[0121] Specifically, preset driving conditions are designed to ensure the safety of vehicle drifting. If the vehicle is going too fast and / or the road surface has a low coefficient of friction, the wheels are prone to slipping, affecting the safety of drifting.

[0122] In one possible implementation, during the initial stage of vehicle drifting, the steering direction corresponding to the rear wheel steering angle is set to the opposite direction of the front wheel steering direction. The front wheel steering direction is determined based on the vehicle's steering wheel direction.

[0123] Specifically, before a vehicle begins to drift, the user typically turns the steering wheel in a certain direction. Then, they quickly counter-steer to initiate the drift. For example, the user might first turn the steering wheel to the left, then quickly turn it to the right, causing the vehicle to fishtail to the right and drift to the right. Therefore, to quickly initiate a drift, the vehicle can control the rear wheels to turn in the opposite direction to the front wheels. For instance, before the vehicle begins to drift, it determines that the user turned the steering wheel to the left based on the steering wheel angle. Based on the example above, it can be deduced that the user might turn the steering wheel to the right after turning left, thus indicating that the user intends to control the vehicle to fishtail to the right. Therefore, controlling the rear wheels to turn to the right assists in fishtailing to the right. This reduces the difficulty of drifting and increases its maneuverability.

[0124] For example, please refer to Figure 3 , Figure 3 This is a schematic diagram illustrating a vehicle drifting motion according to an embodiment of this application. Figure 3 As shown, the vehicle travels from position A to position B, and then from position B to position C. At position A, the vehicle travels in a straight line, with neither the front nor rear wheels turning, indicating that it has not yet drifted. At position B, the front wheels turn to the left and the rear wheels turn to the right. At this point, the user turns the steering wheel to the left, causing the front wheels to turn left. Since the user wants to control the vehicle to drift to the right, to achieve a rightward drift, the vehicle can control the rear wheels to turn in the opposite direction to the front wheels to enter a drift state more quickly and reduce the energy consumption generated by the vehicle's output torque. At position C, the user quickly counter-steers the steering wheel to enter a drift state, i.e., quickly turns the steering wheel to the right, causing the vehicle to drift to the right, achieving a rightward drift.

[0125] In one possible implementation, one or more of the front axle torque, rear axle torque, and rear wheel steering angle are determined based on the difference between the current steering parameters and the target steering parameters.

[0126] In one possible implementation, during vehicle drifting, when the current steering parameter is greater than the target steering parameter, the front axle torque and rear axle torque are determined by reducing the distribution ratio of the rear axle torque in the vehicle's total torque, and / or, the steering direction corresponding to the rear wheel steering angle is set to the opposite direction of the front wheel steering direction, which is determined based on the vehicle's steering wheel direction.

[0127] In this context, a current steering parameter exceeding the target steering parameter can be considered a significant vehicle drift. A significant drift can cause the vehicle's lateral offset angle or lateral velocity to exceed the driver's control, leading to instability and potentially resulting in loss of control or an accident. The lateral offset angle or lateral velocity can be determined based on the vehicle's sideslip angle and / or yaw rate.

[0128] Normally, moderate drifting involves the driver consciously controlling the vehicle's lateral movement to maintain control and stability during driving. However, excessive drifting means the vehicle deviates from the driver's intended trajectory or exceeds the driver's capabilities, potentially leading to dangerous situations such as loss of control, collisions, or rollovers. Therefore, it is essential to control vehicles with significant drifting.

[0129] Specifically, the vehicle determines the front axle torque and rear axle torque by reducing the proportion of rear axle torque in the vehicle's total torque. Reducing the proportion of rear axle torque in the vehicle's total torque can be understood as reducing the driving force on the rear axle, thus reducing the extent of rear wheel sideslip and consequently reducing the vehicle's drift.

[0130] Simultaneously, the direction opposite to the front wheel steering direction is used as the corresponding steering direction for the rear wheels, causing the rear wheels to rotate in the opposite direction to the front wheels. This is because vehicle drifting is primarily achieved through rear wheel sideslip causing a fishtail, and a large vehicle deviation can be understood as a large fishtail. Therefore, by having the rear wheels rotate in the opposite direction to the front wheels, the extent of the fishtail can be reduced to some extent, thereby reducing the overall drift.

[0131] In one possible implementation, during vehicle drifting, when the current steering parameter is less than the target steering parameter, the front axle torque and rear axle torque are determined by increasing the distribution ratio of the rear axle torque in the vehicle's total torque, and / or, the steering direction corresponding to the rear wheel steering angle is set to the front wheel steering direction, which is determined based on the vehicle's steering wheel direction.

[0132] In this context, a current steering parameter being less than the target steering parameter can be considered a smaller drift amplitude. A smaller drift amplitude refers to a smaller lateral offset angle or lateral velocity during the drift, resulting in a drift effect that does not meet the user's expectations, or the vehicle not following the intended drift trajectory. The lateral offset angle or lateral velocity can be determined based on the vehicle's sideslip angle and / or yaw rate.

[0133] Specifically, the vehicle determines the front axle torque and rear axle torque by increasing the proportion of rear axle torque in the vehicle's total torque. Increasing the proportion of rear axle torque in the vehicle's total torque can be understood as increasing the driving force of the rear axle, which increases the extent of rear wheel sideslip, thereby increasing the vehicle's drift range.

[0134] Simultaneously, the steering direction of the front wheels is used as the steering direction corresponding to the steering angle of the rear wheels, causing the rear wheels to rotate in the same direction as the front wheels. Since vehicle drifting is primarily achieved through rear wheel sideslip causing fishtailing, a small vehicle offset can be interpreted as a small fishtailing amplitude. Therefore, by aligning the rear wheels with the front wheels, the fishtailing amplitude can be increased to some extent, thereby increasing the overall drift amplitude.

[0135] In one possible implementation, the rear axle torque includes a first rear wheel torque and a second rear wheel torque of the vehicle, the first rear wheel torque being used to determine a first rear wheel speed of the first rear wheel and the second rear wheel torque being used to determine a second rear wheel speed of the second rear wheel.

[0136] Specifically, the vehicle determines the front axle torque, rear axle torque, and rear wheel steering angle based on steering parameters. Then, the vehicle determines the first rear wheel torque and the second rear wheel torque based on the rear axle torque. The vehicle controls its drifting motion based on the front wheel speed determined by the front wheel torque, the first rear wheel speed determined by the first rear wheel torque, the second rear wheel speed determined by the second rear wheel torque, and the rear wheel steering angle.

[0137] In one possible implementation, when there is a first wheel speed difference between the first rear wheel speed and the second rear wheel speed, the first rear wheel torque and the second rear wheel torque are determined based on the first wheel speed difference to reduce the distribution ratio of the target rear wheel torque in the rear axle torque, and the rear wheel corresponding to the target rear wheel torque is the rear wheel with the larger wheel speed among the first rear wheel and the second rear wheel.

[0138] Specifically, since the first rear wheel torque is used to determine the first rear wheel speed, and the second rear wheel torque is used to determine the second rear wheel speed, when there is a first wheel speed difference between the first and second rear wheel speeds, the vehicle can reduce this first wheel speed difference by controlling the first and second rear wheel torques.

[0139] For example, when a vehicle drifts by sideslipping its rear wheels, the vehicle's load shifts laterally during the drift. Specifically, the vertical load on the outer wheels increases, while the vertical load on the inner wheels decreases. For instance, when the vehicle drifts to the right, the right side is the outer wheel and the left side is the inner wheel. In this case, the load on the right rear wheel increases, while the load on the left rear wheel decreases.

[0140] If the torque of the first rear wheel is equal to the torque of the second rear wheel, then the driving force transmitted to the first and second rear wheels by the vehicle is also equal. However, since the load on the first and second rear wheels is not equal, the wheel speeds generated by the first and second rear wheels under the same driving force are not equal. That is, there will be a first wheel speed difference between the first and second rear wheels.

[0141] In one possible implementation, the vehicle uses sensors to acquire the wheel speeds of the first and second rear wheels. For example, the vehicle acquires the wheel speeds by installing wheel speed sensors near the wheels. When a first wheel speed difference exists between the second wheel speeds of the first and second rear wheels acquired by the sensors, the vehicle determines the first and second rear wheel torques based on this first wheel speed difference. Then, the vehicle is controlled to drift based on the front wheel speeds, the first rear wheel torque, the second rear wheel torque, and the rear wheel steering angle.

[0142] For example, if the speed of the second rear wheel is greater than the speed of the first rear wheel, then the second rear wheel is the target rear wheel, and also the inner rear wheel when the vehicle is drifting. The vehicle determines the torque of the first and second rear wheels by reducing the proportion of the torque distributed between the second rear wheel and the rear axle torque.

[0143] It should be noted that since rear wheel torque can be used to determine the wheel speed of the corresponding wheel, reducing the proportion of the target rear wheel torque in the rear axle torque is equivalent to reducing the wheel speed of the target rear wheel. This makes the wheel speed of the first rear wheel basically the same as that of the second rear wheel, reducing the risk caused by the difference in wheel speed between the first and second rear wheels.

[0144] In one possible implementation, the front axle torque includes a first front wheel torque and a second front wheel torque of the vehicle, the first front wheel torque being used to determine a first front wheel speed of the first front wheel of the vehicle, and the second front wheel torque being used to determine a second front wheel speed of the second front wheel of the vehicle.

[0145] In one possible implementation, when there is a second wheel speed difference between the first front wheel speed and the second front wheel speed, the first front wheel torque and the second front wheel torque are determined based on the second wheel speed difference to reduce the distribution ratio of the target front wheel torque in the front axle torque, and the front wheel corresponding to the target front wheel torque is the front wheel with the larger wheel speed among the first front wheel and the second front wheel.

[0146] Specifically, since the first front wheel torque is used to determine the first front wheel speed, and the second front wheel torque is used to determine the second front wheel speed, when there is a second wheel speed difference between the first and second front wheel speeds, the vehicle can reduce this difference by controlling the first and second front wheel torques.

[0147] For example, if the speed of the second front wheel is greater than the speed of the first front wheel, then the second front wheel is the target front wheel. The vehicle determines the torque of the first and second front wheels by reducing the proportion of torque distributed to the second front wheel in the total front axle torque.

[0148] Understandably, since front wheel torque can be used to determine the wheel speed of the corresponding wheel, reducing the proportion of the target front wheel torque in the front axle torque is equivalent to reducing the target front wheel speed. This makes the wheel speed of the first front wheel essentially the same as the wheel speed of the second front wheel, reducing the risk caused by the difference in wheel speed between the first and second front wheels.

[0149] The above embodiments describe how a vehicle reduces the first wheel speed difference between the first and second rear wheels by adjusting the torque of the first and second rear wheels, and how it reduces the second wheel speed difference between the first and second front wheels by adjusting the torque of the first and second front wheels. The following will specifically describe how the vehicle reduces the first and / or second wheel speed differences through braking.

[0150] In one possible implementation, when the vehicle's rear axle includes a motor (e.g., a single rear axle motor or dual front and rear motors), if a first wheel speed difference exists between the first and second rear wheel speeds, the vehicle can reduce this difference by braking the target rear wheel, thereby improving the vehicle's drift stability. The target rear wheel is the one with the higher wheel speed among the first and second rear wheels.

[0151] In one possible implementation, the vehicle may have one motor on the front axle, or no motor on the front axle at all, for example, a vehicle with one motor on the rear axle, two motors on the rear axle, three motors, or both front and rear motors. When there is a first wheel speed difference between the first and second front wheel speeds, the vehicle can reduce this difference by braking the target front wheel, thereby improving the stability of the vehicle's drift. The target front wheel is the one with the higher wheel speed among the first and second front wheels.

[0152] It should be noted that if a first-wheel speed difference exists between the first and second rear wheels, and / or a second-wheel speed difference exists between the first and second front wheels, a series of problems may occur. For example, the first-wheel speed difference and / or the second-wheel speed difference may cause an imbalance in the vehicle's traction. Simultaneously, a wheel speed greater than the other may cause the tire on that wheel to slip or lose traction, while a slower wheel speed on the other side may result in insufficient traction, affecting the vehicle's power transmission and acceleration performance. Therefore, in this embodiment, adjusting the torque of the first and second rear wheels can reduce the first-wheel speed difference, and adjusting the torque of the first and second front wheels can reduce the second-wheel speed difference. Furthermore, braking the target front wheel with a higher wheel speed can reduce the second-wheel speed difference, and braking the target rear wheel with a higher wheel speed can reduce the first-wheel speed difference. This improves the stability of the vehicle during drifting and extends the drift distance.

[0153] In one possible implementation, at the end of the vehicle's drift phase, the steering direction corresponding to the rear wheel steering angle is set to the front wheel steering direction. The front wheel steering direction is determined based on the vehicle's steering wheel direction.

[0154] Specifically, setting the steering direction corresponding to the rear wheel steering angle to the front wheel steering direction can reduce the vehicle's fishtailing amplitude, help the vehicle straighten out, and thus end the drift.

[0155] Please see Figure 4 , Figure 4 This is a schematic diagram of a U-shaped curve drift provided in an embodiment of this application. Figure 4 As shown, the vehicle drifts from position A, through positions B, C, and D, to position E. At position A, the vehicle is traveling in a straight line, with neither the front nor rear wheels turning, indicating that it has not yet drifted. At position B, the front wheels turn to the left and the rear wheels turn to the right. At this point, the user turns the steering wheel to the left, causing the front wheels to turn to the left. Since the user intends to control the vehicle to drift to the right, achieving a rightward drift, the vehicle will drift to the right... Figure 4 The U-shaped bend. Therefore, in order to allow the vehicle to enter a drift state more quickly and reduce the energy consumption generated by the vehicle's output torque, the vehicle can control the rear wheels to turn in the opposite direction to the front wheels, that is, at this time the vehicle controls the rear wheels to turn to the right. At position C, the user quickly counter-steering by turning the steering wheel to the right, causing the vehicle to fishtail to the right, thus achieving a rightward drift.

[0156] like Figure 4As shown, as the vehicle moves from position B to position C, the drift amplitude increases, meaning the fishtailing amplitude increases. The fishtailing amplitude can be increased by increasing the proportion of rear axle torque in the total torque distribution, thereby increasing the driving force of the rear axle, and simultaneously controlling the rotation direction of the rear wheels to be the same as that of the front wheels.

[0157] like Figure 4 As shown, as the vehicle moves from position C to position D, the drift amplitude decreases, meaning the fishtailing amplitude decreases. This can be achieved by reducing the proportion of rear axle torque in the total torque distribution, thereby reducing the driving force on the rear axle. Simultaneously, controlling the rear wheels to rotate in the opposite direction to the front wheels further reduces the fishtailing amplitude. Therefore, when the vehicle is driving through a curve, such as when moving from position B to position C and then to position D, the vehicle can drift along the trajectory desired by the user. Moving from position D to position E, it can be seen that the vehicle has exited the curve, and at position E, the vehicle has straightened its direction.

[0158] Vehicles passing Figure 4 During the U-shaped bend shown, the vehicle can determine the front axle torque, rear axle torque, and rear wheel steering angle in real time through steering parameters. Based on these parameters, the vehicle can control itself to drift along the desired trajectory. Simultaneously, the vehicle determines the first and second rear wheel torques based on the rear axle torque. This, in turn, adjusts the first wheel speed difference between the first and second rear wheels, ensuring that their speeds are equal or close to each other. Similarly, the vehicle determines the first and second front wheel torques based on the front axle torque. This, in turn, adjusts the second wheel speed difference between the first and second front wheels, ensuring that their speeds are equal or close to each other, thus improving vehicle stability.

[0159] Please see Figure 5 , Figure 5 This is a schematic diagram of an L-shaped curve drift provided in an embodiment of this application. Figure 5 As shown, the vehicle drifts from position A, through positions B, C, and D, to position E. At position A, the vehicle is traveling in a straight line, with neither the front nor rear wheels turning, indicating that it has not yet drifted. At position B, the front wheels turn to the left and the rear wheels turn to the right. At this point, the user turns the steering wheel to the left, causing the front wheels to turn to the left. Since the user intends to control the vehicle to drift to the right, achieving a rightward drift, the vehicle will drift to the right... Figure 5The road has an L-shaped bend. Therefore, to allow the vehicle to enter a drift state more quickly and reduce energy consumption from the vehicle's output torque, the vehicle can control the rear wheels to turn in the opposite direction to the front wheels; that is, the vehicle controls the rear wheels to turn to the right. At position C, the user quickly counter-steers the steering wheel to enter a drift state; that is, the user quickly turns the steering wheel to the right, causing the vehicle to fishtail to the right, thus achieving a rightward drift.

[0160] like Figure 5 As shown, as the vehicle moves from position B to position C, the drift amplitude increases, meaning the fishtailing amplitude increases. The fishtailing amplitude can be increased by increasing the proportion of rear axle torque in the total torque distribution, thereby increasing the driving force of the rear axle, and simultaneously controlling the rotation direction of the rear wheels to be the same as that of the front wheels.

[0161] like Figure 5 As shown, at position D, as the vehicle exits the curve, the user turns the steering wheel to the left, causing the car to exit the curve with its front end pointing left. During this exit, the vehicle can determine the front axle torque, rear axle torque, and rear wheel steering angle in real time using steering parameters. Based on these parameters, the vehicle can be controlled to drift along a desired trajectory. For example, by adjusting the front axle torque, rear axle torque, and rear wheel steering angle, the vehicle's lateral speed can be reduced to zero before it approaches the edge of the road. This shortens the drift time, increases the drift speed, and improves the vehicle's track performance.

[0162] Please see Figure 6 , Figure 6 This is a schematic diagram of a fixed-circle drift provided in an embodiment of this application. For example... Figure 6 As shown, the vehicle drifts along a circular trajectory around a reference point. First, the user gradually accelerates the vehicle and controls the steering wheel. Then, the steering wheel is quickly reversed to initiate a drift. During the drift, the rear wheel steering angle is controlled to assist in adjusting the vehicle's orientation, ensuring it continues drifting along a circular trajectory.

[0163] exist Figure 6 Throughout the drifting process shown, the involvement of rear-wheel steering reduces the skill requirements for the user and increases the vehicle's stability during drifting. Compared to existing technologies, the front-to-rear axle torque distribution and rear-wheel torque distribution can be controlled by algorithms to track the user's desired drift trajectory. Simultaneously, it optimizes energy consumption and the load on actuators related to vehicle drifting, enabling longer drifting durations. Therefore, the method provided in this application can serve as a basis for objectives such as automatic drifting along a preset trajectory and achieving the longest possible drift distance for impact vehicles.

[0164] Please see Figure 7 , Figure 7 This is a schematic diagram of a figure-eight drift provided in an embodiment of this application. For example... Figure 7 As shown, the vehicle drifts in a figure-eight pattern. First, the user controls the vehicle's steering wheel, gradually increasing speed. Then, a quick counter-steering motion initiates the drift. During the drift, the vehicle distributes torque to both the front and rear axles, while simultaneously controlling the rear wheel steering, allowing the vehicle to adjust its posture in real time and drift along the figure-eight trajectory. Figure 6 Similar to the fixed-circle drift shown, the advantage of this embodiment lies in optimizing the energy consumption generated during vehicle drifting and the load on actuators related to vehicle drifting. It can accurately track the drift trajectory expected by the user and can also serve as the basis for achieving automatic drifting along an "8" trajectory.

[0165] In summary, the drift control method provided in this application demonstrates good drift performance in various drift scenarios, including U-shaped, L-shaped, circular, and figure-eight drifts. Therefore, by distributing front and rear axle torque and simultaneously controlling rear wheel steering, the fast cornering requirements in track racing scenarios can be better met. Compared to existing drift control solutions, the method provided in this application offers better control performance and stability. In performance-oriented scenarios such as circular and figure-eight drifts, this application provides better tracking of the user's desired trajectory compared to existing solutions. It also reduces the skill requirements for drifting, allowing beginners to quickly learn and perform circular and figure-eight drifts, experiencing the joy of drifting. Because it optimizes energy consumption and actuator load during vehicle drifting, and possesses trajectory tracking performance, it provides a solid foundation for automatically tracking drift trajectories, recording impact drifts, and even using drifts for emergency obstacle avoidance.

[0166] Please see Figure 8 , Figure 8 This is a schematic flowchart illustrating a drift control method provided in an embodiment of this application. Figure 8 As shown, the process includes one or more steps S801-S805, and the specific steps are as follows:

[0167] S801, Determine if drift mode is activated. To ensure driving safety, the vehicle can determine whether drift mode is activated before initiating drift control. For example, the user can activate drift mode via a physical button on the vehicle or a function control on the display screen, and the vehicle will receive the corresponding drift mode activation signal.

[0168] The vehicle then undergoes a series of checks to determine whether to initiate drift control. These checks include whether occupants are wearing seatbelts, doors are closed, battery power is sufficient, and the actuators used for drifting are functioning correctly. If the checks pass, and all conditions are confirmed to be normal, the vehicle initiates drift mode and enters step S802. If the checks fail, the vehicle does not initiate drift mode and the process ends.

[0169] S802, Obtain vehicle speed and road surface adhesion coefficient. The vehicle can determine estimated values ​​for vehicle speed and road surface adhesion coefficient based on the acquired driving parameters, and then adopt corresponding drift control strategies accordingly. The road surface adhesion coefficient refers to the coefficient of friction between the tires and the road surface, and is commonly used to measure a vehicle's grip under different road conditions. For example, the vehicle can assess the road surface adhesion coefficient by monitoring wheel speed and steering angle, thereby determining an estimated value for the road surface adhesion coefficient.

[0170] S803, determine if drift requirements are met. Specifically, when the estimated value of the road surface adhesion coefficient is greater than the calibrated threshold, it indicates that the friction between the tires and the road surface is high, and the grip between the wheels and the ground is also high. Therefore, the vehicle can increase the torque distribution to the rear axle, allowing the rear wheels to generate more driving force to achieve a drift. When the estimated value of the road surface adhesion coefficient is less than or equal to the calibrated threshold, it indicates that the friction between the tires and the road surface is low, and the grip between the wheels and the ground is also low. Therefore, the vehicle can achieve a drift without distributing a large amount of torque to the rear axle, saving energy. When the estimated values ​​of vehicle speed and road surface adhesion coefficient are within the calibrated range, proceed to S804; when the estimated values ​​of vehicle speed and road surface adhesion coefficient are not within the calibrated range, return to S801.

[0171] S804 acquires vehicle driving parameters. The vehicle can acquire driving parameters through one or more sensors installed on the vehicle. Based on the acquired driving parameters, the vehicle can determine its driving state in real time, and thus perform drift control based on the driving state.

[0172] For example, driving parameters may include one or more of the following: vehicle speed, steering wheel angle, accelerator pedal depth, wheel speed, brake pedal depth, and the road surface adhesion coefficient. Among these, the steering wheel angle, accelerator pedal depth, and brake pedal depth can be user-controlled. The vehicle can determine whether the user has initiated a drift by steering based on the steering wheel angle, and also determine the user's desired drift amplitude. The accelerator pedal depth and / or brake pedal depth can be used to determine the vehicle's total torque, which in turn is used to determine the front axle torque and rear axle torque. Vehicle speed and wheel speed characterize the vehicle's current driving state.

[0173] S805 determines the front axle torque, rear axle torque, and rear wheel steering angle. The vehicle determines the total torque and rear wheel steering angle based on driving parameters, and then determines the front axle torque and rear axle torque based on the total torque and driving parameters. Simultaneously, the vehicle also determines the rear wheel steering angle based on driving parameters. The rear wheel steering angle includes the direction and magnitude of the rear wheel steering angle. The direction of the rear wheel steering angle determines whether the rear wheels are turning left or right, and the magnitude of the rear wheel steering angle determines the degree of rear wheel steering.

[0174] After the vehicle outputs the corresponding front axle torque, rear axle torque, and rear wheel steering angle based on the currently acquired driving parameters, it returns to step S801. Therefore, the vehicle can acquire driving parameters at preset intervals and then control the drift. Thus, this embodiment can control the vehicle's drift driving in real time to meet the vehicle's real-time condition requirements.

[0175] Throughout the entire control process, drift mode must remain active, meaning the switch must not be turned off by the driver, and all occupants must be wearing seatbelts. If any abnormality is detected, the vehicle will disengage from drift control.

[0176] Please see Figure 9 , Figure 9 This is a schematic diagram of a drift control method provided in an embodiment of this application. Figure 9 As shown, this embodiment of the application achieves the target steering parameter control objective by using a method of front-to-rear axle torque distribution and rear-wheel steering coordination, based on the vehicle's current state, such as its current driving parameters. The target steering parameter is a desired value determined by the vehicle based on the driving parameters. For example, the vehicle determines its target yaw rate and / or target sideslip angle for the next moment based on the driving parameters obtained at the current moment. The vehicle uses the front-to-rear axle torque distribution and rear-wheel steering coordination method to ensure that the vehicle's yaw rate reaches the target yaw rate and / or its sideslip angle reaches the target sideslip angle.

[0177] The vehicle achieves the control objective of improving vehicle stability by using rear-wheel torque distribution methods and taking into account the vehicle's state, such as, but not limited to, lateral acceleration and wheel speed.

[0178] The methods of the embodiments of this application have been described in detail above. The apparatus of the embodiments of this application is provided below.

[0179] Please see Figure 10 , Figure 10 This is a functional unit block diagram of an electronic device provided in an embodiment of this application. The vehicle electronic device 100 may include a determining unit 1001 and a processing unit 1002. The vehicle electronic device 100 is used to implement the aforementioned vehicle drift control method, for example... Figure 2 The vehicle drift control method shown.

[0180] It should be noted that the above division of multiple units is only a logical division based on function and does not constitute a limitation on the specific structure of the vehicle electronic device 100. In actual implementation, some functional modules may be subdivided into more smaller functional modules, and some functional modules may be combined into a single functional module.

[0181] In one possible implementation, the determining unit 1001 is used to determine the vehicle torque and rear wheel steering angle corresponding to the vehicle drifting when the vehicle needs to drift.

[0182] The processing unit 1002 is used to control the vehicle to drift based on the vehicle torque and the rear wheel steering angle.

[0183] In another possible implementation, the vehicle torque includes the front axle torque and / or the rear axle torque of the vehicle.

[0184] In another possible implementation, one or more of the front axle torque, the rear axle torque, and the rear wheel steering angle are determined based on the vehicle's steering parameters.

[0185] In another possible implementation, the vehicle's steering parameters include the vehicle's current steering parameters and the vehicle's target steering parameters, wherein one or more of the front axle torque, the rear axle torque, and the rear wheel steering angle are determined based on the difference between the current steering parameters and the target steering parameters.

[0186] In another possible implementation, the current steering parameters include the vehicle's current center of gravity yaw angle and / or the vehicle's current yaw rate, and the target steering parameters include the vehicle's target center of gravity yaw angle and / or the vehicle's target yaw rate.

[0187] In another possible implementation, the target steering parameter is determined based on the vehicle's driving parameters, which include one or more of the vehicle's speed, steering wheel angle, accelerator pedal depth, wheel speed, brake pedal depth, and the road surface adhesion coefficient of the road surface on which the vehicle is traveling.

[0188] In another possible implementation, during the vehicle's drift, when the current steering parameter is greater than the target steering parameter:

[0189] The front axle torque and the rear axle torque are determined by reducing the proportion of the rear axle torque in the total torque of the vehicle; and / or,

[0190] The steering direction corresponding to the rear wheel steering angle is set to the opposite direction of the front wheel steering direction, which is determined based on the steering wheel direction of the vehicle.

[0191] In another possible implementation, during the vehicle's drift, when the current steering parameter is less than the target steering parameter:

[0192] The front axle torque and the rear axle torque are determined by increasing the proportion of the rear axle torque in the total torque of the vehicle; and / or,

[0193] The steering direction corresponding to the rear wheel steering angle is set as the front wheel steering direction, which is determined based on the steering wheel direction of the vehicle.

[0194] In another possible implementation, the rear axle torque includes a first rear wheel torque and a second rear wheel torque of the vehicle, wherein the first rear wheel torque is used to determine a first rear wheel speed of the first rear wheel and the second rear wheel torque is used to determine a second rear wheel speed of the second rear wheel.

[0195] In another possible implementation, when there is a first wheel speed difference between the first rear wheel speed and the second rear wheel speed, the first rear wheel torque and the second rear wheel torque are determined based on the first wheel speed difference to reduce the distribution ratio of the target rear wheel torque in the rear axle torque, and the rear wheel corresponding to the target rear wheel torque is the rear wheel with the larger wheel speed between the first rear wheel and the second rear wheel.

[0196] In another possible implementation, the front axle torque includes a first front wheel torque and a second front wheel torque of the vehicle, wherein the first front wheel torque is used to determine a first front wheel speed of the first front wheel of the vehicle, and the second front wheel torque is used to determine a second front wheel speed of the second front wheel of the vehicle.

[0197] In another possible implementation, when there is a second wheel speed difference between the first front wheel speed and the second front wheel speed, the first front wheel torque and the second front wheel torque are determined based on the second wheel speed difference to reduce the distribution ratio of the target front wheel torque in the front axle torque, and the front wheel corresponding to the target front wheel torque is the front wheel with the larger wheel speed between the first front wheel and the second front wheel.

[0198] In another possible implementation, during the initial stage of the vehicle's drift, the steering direction corresponding to the rear wheel steering angle is set to the opposite direction of the front wheel steering direction; and / or,

[0199] At the end of the vehicle's drift phase, the steering direction corresponding to the rear wheel steering angle is set to the front wheel steering direction;

[0200] The direction of front wheel steering is determined based on the direction of the vehicle's steering wheel.

[0201] In another possible implementation, the operation of controlling the vehicle to drift based on the vehicle torque and the rear wheel steering angle is performed only when the vehicle's driving condition meets preset driving condition conditions;

[0202] The preset driving conditions include: the vehicle speed is within a preset speed range, and / or the road surface adhesion coefficient of the road surface on which the vehicle travels is within a preset adhesion coefficient range.

[0203] It should be noted that, in the embodiments of this application, the specific implementation and technical effects of each unit can also be referred to accordingly. Figure 2 The corresponding description of the method embodiments shown.

[0204] Please see Figure 11 , Figure 11 This is a schematic diagram of the structure of another electronic device provided in an embodiment of this application. For example... Figure 11 As shown, the electronic device 110 may include one or more processors 1101, one or more memories 1102, and one or more communication interfaces 1103. These components may be connected via a bus 1104 or other means. Figure 11 Taking a connection via bus 1104 as an example. Where:

[0205] The communication interface 1103 can be used by the electronic device 110 to communicate with other communication devices, such as other electronic devices. Specifically, the communication interface 1103 can be a wired interface.

[0206] The memory 1102 can be coupled to the processor 1101 via a bus 1104 or an input / output port, or the memory 1102 can be integrated with the processor 1101. The memory 1102 is used to store various software programs and / or multiple sets of instructions or data. Specifically, the memory 1102 can be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or it can be an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), a magnetic disk storage medium or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited thereto. Memory 1102 may include high-speed random access memory and may also include non-volatile memory, such as one or more disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. Memory 1102 may store an operating system (hereinafter referred to as the system), such as uCOS, VxWorks, RTLinux, or other embedded operating systems. Memory 1102 may also store network communication programs that can be used to communicate with one or more additional devices, one or more user devices, or one or more terminals. Memory 1102 may exist independently and be connected to processor 1101 via bus 1104. Memory 1102 may also be integrated with processor 1101.

[0207] The memory 1102 stores the application code for executing the above scheme, and its execution is controlled by the processor 1101. The processor 1101 executes the application code stored in the memory 1102.

[0208] Processor 1101 may be a central processing unit, a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field-programmable gate array, or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It may implement or execute the various exemplary logic blocks, modules, and circuits described in connection with this disclosure. Processor 1101 may also be a combination that implements a specific function, such as a combination of one or more microprocessors, a combination of a digital signal processor and a microprocessor, etc.

[0209] This application also provides a vehicle, the vehicle including... Figure 10 The electronic device shown and Figure 11 The electronic device shown.

[0210] This application also provides a computer-readable storage medium storing instructions that, when executed on at least one processor, implement the aforementioned vehicle drift control method, for example... Figure 2 The method.

[0211] In this application, the terms "for example" or "for instance" are used to indicate that something is being described as an example, illustration, or illustration. Any embodiment or design described as "for example" or "for instance" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Rather, the use of terms such as "for example" or "for instance" is intended to present the relevant concepts in a specific manner.

[0212] In this application, "at least one" in the embodiments refers to one or more items, and "more than one" refers to two or more items. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, at least one of a, b, or c can represent: a, b, c, (a and b), (a and c), (b and c), or (a and b and c), where a, b, and c can be single or multiple. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship.

[0213] Furthermore, unless otherwise stated, the use of ordinal numbers such as "first" and "second" in the embodiments of this application is for distinguishing multiple objects and is not for limiting the order, sequence, priority, or importance of multiple objects. For example, "first device" and "second device" are only for ease of description and do not indicate that the first device and the second device are different in structure, importance, etc. In some embodiments, the first device and the second device may also be the same device.

[0214] In the above embodiments, the term "when..." can be interpreted, depending on the context, as meaning "if...", "after...", "in response to determining...", or "in response to detecting...". The above are merely optional embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the concept and principles of this application should be included within the protection scope of this application.

[0215] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware or by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

[0216] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered 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 vehicle drift control method, characterized in that, The method includes: When a vehicle needs to drift, determine the front axle torque, rear axle torque, and rear wheel steering angle corresponding to the vehicle's drifting motion. During the drifting process of the vehicle, based on the difference between the current steering parameters and the target steering parameters of the vehicle, the distribution ratio of the rear axle torque in the total torque of the vehicle is adjusted to determine the adjusted front axle torque and rear axle torque, as well as the adjusted rear wheel steering angle. The vehicle is controlled to drift based on the adjusted front axle torque, rear axle torque, and rear wheel steering angle.

2. The method according to claim 1, characterized in that, The current steering parameters include the vehicle's current center of gravity yaw angle and / or the vehicle's current yaw rate, and the target steering parameters include the vehicle's target center of gravity yaw angle and / or the vehicle's target yaw rate.

3. The method according to claim 1 or 2, characterized in that, The target steering parameters are determined based on the vehicle's driving parameters, which include one or more of the vehicle's speed, steering wheel angle, accelerator pedal depth, wheel speed, brake pedal depth, and the road surface adhesion coefficient of the road surface on which the vehicle is driving.

4. The method according to claim 1, characterized in that, During the vehicle's drift, when the current steering parameter is greater than the target steering parameter: The front axle torque and the rear axle torque are determined by reducing the proportion of the rear axle torque in the total torque of the vehicle; The steering direction corresponding to the rear wheel steering angle is set to the opposite direction of the front wheel steering direction, which is determined based on the steering wheel direction of the vehicle.

5. The method according to claim 1, characterized in that, During the vehicle's drift, when the current steering parameter is less than the target steering parameter: The front axle torque and the rear axle torque are determined by increasing the proportion of the rear axle torque in the total torque of the vehicle; The steering direction corresponding to the rear wheel steering angle is set as the front wheel steering direction, which is determined based on the steering wheel direction of the vehicle.

6. The method according to claim 1, characterized in that, The rear axle torque includes the first rear wheel torque and the second rear wheel torque of the vehicle. The first rear wheel torque is used to determine the first rear wheel speed of the first rear wheel, and the second rear wheel torque is used to determine the second rear wheel speed of the second rear wheel.

7. The method according to claim 6, characterized in that, When there is a first wheel speed difference between the first rear wheel speed and the second rear wheel speed, the first rear wheel torque and the second rear wheel torque are determined based on the first wheel speed difference to reduce the distribution ratio of the target rear wheel torque in the rear axle torque. The rear wheel corresponding to the target rear wheel torque is the rear wheel with the larger wheel speed between the first rear wheel and the second rear wheel.

8. The method according to claim 1, characterized in that, The front axle torque includes the first front wheel torque and the second front wheel torque of the vehicle. The first front wheel torque is used to determine the first front wheel speed of the first front wheel of the vehicle, and the second front wheel torque is used to determine the second front wheel speed of the second front wheel of the vehicle.

9. The method according to claim 8, characterized in that, When there is a second wheel speed difference between the first front wheel speed and the second front wheel speed, the first front wheel torque and the second front wheel torque are determined based on the second wheel speed difference to reduce the distribution ratio of the target front wheel torque in the front axle torque. The front wheel corresponding to the target front wheel torque is the front wheel with the larger wheel speed between the first front wheel and the second front wheel.

10. The method according to claim 4 or 5, characterized in that, During the initial stage of the vehicle's drift, the steering direction corresponding to the rear wheel steering angle is set to the opposite direction of the front wheel steering direction; At the end of the vehicle's drift phase, the steering direction corresponding to the rear wheel steering angle is set to the front wheel steering direction; The direction of front wheel steering is determined based on the direction of the vehicle's steering wheel.

11. The method according to claim 1, characterized in that, The operation of controlling the vehicle to drift based on the vehicle torque and the rear wheel steering angle is only performed when the vehicle's driving condition meets the preset driving condition conditions; The preset driving conditions include: the vehicle speed is within a preset speed range, and / or the road surface adhesion coefficient of the road surface on which the vehicle travels is within a preset adhesion coefficient range.

12. An electronic device, characterized in that, The device includes: The determining unit is used to determine the front axle torque, rear axle torque, and rear wheel steering angle corresponding to the vehicle's drifting motion when the vehicle needs to drift. The determining unit is also used to, during the drifting process of the vehicle, adjust the distribution ratio of the rear axle torque in the total torque of the vehicle based on the difference between the current steering parameters and the target steering parameters of the vehicle, determine the adjusted front axle torque and rear axle torque, and determine the adjusted rear wheel steering angle; The processing unit is used to control the vehicle to drift based on the adjusted front axle torque, rear axle torque, and rear wheel steering angle.

13. An electronic device, characterized in that, The method includes a processor connected to a memory for storing a computer program, the processor for calling and running the computer program to perform the method as described in any one of claims 1-11.

14. A vehicle, characterized in that, The vehicle includes the electronic device as described in claim 12 or claim 13.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, the computer program including instructions for performing the method as described in any one of claims 1-11.

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