Vehicle torque distribution method, device, vehicle and computer-readable storage medium

Abstract

Embodiments of the present invention relate to the field of vehicle control technology and disclose a vehicle torque distribution method, apparatus, vehicle, and computer-readable storage medium. The method comprises: activating a cornering yaw control function upon detecting that the vehicle meets activation conditions; determining a feedforward correction value according to an advance prediction strategy and a feedback correction value according to a feedback control strategy under the cornering yaw control function; and adjusting the vehicle's torque distribution based on the feedforward correction value, the feedback correction value, and preset upper and lower limits. Application of the present invention's technical solution can reduce the frequency of ESC intervention, thereby avoiding abrupt driver sensations during cornering.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of vehicle control technology, and more particularly to a vehicle torque distribution method, device, vehicle, and computer-readable storage medium. Background Art

[0002] Currently, when a vehicle oversteers or understeers while passing a curve, intervention through the ESC (electronic stability control system) will give the driver a sense of abruptness. Summary of the Invention

[0003] In view of the above problems, an embodiment of the present invention provides a vehicle torque distribution method, device, vehicle and computer-readable storage medium, which are used to solve the problem in the prior art that when the vehicle oversteers or understeers through a curve, the ESC intervention control will give the driver a sudden feeling.

[0004] According to one aspect of an embodiment of the present invention, a vehicle torque distribution method is provided, the method comprising:

[0005] When it is detected that the vehicle meets the activation conditions, the cornering yaw control function is turned on;

[0006] Under the curve yaw control function, the feedforward correction value is determined according to the advance prediction strategy, and the feedback correction value is determined according to the feedback control strategy;

[0007] The torque distribution of the vehicle is adjusted based on the feedforward correction value, the feedback correction value, and preset upper and lower limits.

[0008] According to another aspect of an embodiment of the present invention, a vehicle torque distribution device is provided, comprising:

[0009] An activation module is used to activate the curve yaw control function when it is detected that the vehicle meets the activation conditions;

[0010] a determination module, for determining a feedforward correction value according to an advance prediction strategy and a feedback correction value according to a feedback control strategy under a curve yaw control function;

[0011] An adjustment module is used to adjust the torque distribution of the vehicle based on the feedforward correction value, the feedback correction value and preset upper and lower limits.

[0012] According to another aspect of an embodiment of the present invention, there is provided a vehicle, comprising:

[0013] A processor, a memory, a communication interface, and a communication bus, wherein the processor, the memory, and the communication interface communicate with each other via the communication bus;

[0014] The memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform the vehicle torque distribution operation as described above.

[0015] According to another aspect of an embodiment of the present invention, a computer-readable storage medium is provided, wherein the storage medium stores at least one executable instruction, wherein the executable instruction enables the vehicle torque distribution device / apparatus to perform the vehicle torque distribution operation described above.

[0016] An embodiment of the present invention activates a cornering yaw control function upon detecting that a vehicle meets activation conditions; within the cornering yaw control function, determines a feedforward correction value based on an advance prediction strategy, and determines a feedback correction value based on a feedback control strategy; and adjusts the vehicle's torque distribution based on the feedforward correction value, the feedback correction value, and preset upper and lower limits. By activating the cornering yaw control function upon detecting that the vehicle meets activation conditions, the aforementioned method effectively prevents false triggering and frequent activation of the cornering yaw control function. The feedforward correction value, the feedback correction value, and the preset upper and lower limits are then combined to adjust the vehicle's torque distribution to improve the vehicle's understeer or oversteer characteristics. This not only improves the vehicle's understeer or oversteer characteristics during cornering without changing the hardware configuration, thereby enhancing the vehicle's cornering performance, but also reduces the frequency of ESC intervention, thereby avoiding abrupt cornering sensations for the driver.

[0017] The above description is only an overview of the technical solutions of the embodiments of the present invention. In order to more clearly understand the technical means of the embodiments of the present invention, they can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiments of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are specifically listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are only used to illustrate the embodiments and are not to be considered as limiting the present invention. In addition, the same reference symbols are used to represent the same components throughout the drawings. In the drawings:

[0019] Figure 1 A schematic flow chart showing a first embodiment of a vehicle torque distribution method provided by the present invention is shown;

[0020] Figure 2 A schematic diagram of a vehicle system in a first embodiment of a vehicle torque distribution method provided by the present invention is shown;

[0021] Figure 3 A schematic flow chart showing a second embodiment of the vehicle torque distribution method provided by the present invention is shown;

[0022] Figure 4A schematic flow chart showing a third embodiment of the vehicle torque distribution method provided by the present invention;

[0023] Figure 5 A schematic flow chart showing a fourth embodiment of the vehicle torque distribution method provided by the present invention;

[0024] Figure 6 A schematic diagram of a curve yaw control function in a fourth embodiment of a vehicle torque distribution method provided by the present invention is shown;

[0025] Figure 7 A schematic flow chart showing a fifth embodiment of the vehicle torque distribution method provided by the present invention;

[0026] Figure 8 A schematic flow chart showing a sixth embodiment of the vehicle torque distribution method provided by the present invention;

[0027] Figure 9 A schematic flow chart showing a seventh embodiment of the vehicle torque distribution method provided by the present invention;

[0028] Figure 10 A schematic flow chart showing a slope transition strategy in a seventh embodiment of the vehicle torque distribution method provided by the present invention is shown;

[0029] Figure 11 A schematic structural diagram of a first embodiment of a vehicle torque distribution device provided by the present invention is shown;

[0030] Figure 12 A schematic structural diagram of an embodiment of a vehicle provided by the present invention is shown.

[0031] Reference numerals:

[0032] 1-Front axle centralized drive motor; 2-Rear axle centralized drive motor; 3-Power battery; 4-Vehicle controller; 5-Motor controller. DETAILED DESCRIPTION

[0033] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0034] Figure 1 FIG1 shows a flow chart of a first embodiment of a vehicle torque distribution method according to the present invention, which is executed by a vehicle controller. Figure 1 As shown, the method includes the following steps:

[0035] Step 110: When it is detected that the vehicle meets the activation conditions, the curve yaw control function is turned on.

[0036] The vehicle may be a four-wheel drive electric vehicle, such as Figure 2 As shown, the vehicle's four-wheel drive electric system includes a front axle centralized drive motor 1, a rear axle centralized drive motor 2, a power battery 3, a vehicle controller 4, and a motor controller (including front and rear motors) 5. The front axle centralized drive motor 1 and the rear axle centralized drive motor 2 are both connected to the wheels through a transmission system.

[0037] Among them, the activation condition is the condition for turning on the curve yaw control function. The setting of the activation condition can be used to prevent the curve yaw control function from being triggered incorrectly and frequently; the curve yaw control function can be used to control the lateral stability of the vehicle when the vehicle is turning, so as to prevent the vehicle from skidding or losing control in a curve.

[0038] In one embodiment, the activation condition may be set based on vehicle information when the vehicle is turning, such as the vehicle speed when the vehicle is turning, and steering wheel rotation information when the vehicle is turning.

[0039] In one embodiment, when it is detected that the vehicle does not meet the activation conditions, that is, when the vehicle does not meet the conditions for turning on the curve yaw control function, the vehicle's torque is distributed according to a fixed front and rear axle torque ratio to meet the vehicle's longitudinal control function. The distribution ratio used for the fixed front and rear axle torque ratio is the proportion of the front axle torque. Preferably, the fixed front and rear axle torque ratio is between 0.4 and 0.6.

[0040] Step 120: Under the curve yaw control function, determine a feedforward correction value according to the advance prediction strategy, and determine a feedback correction value according to the feedback control strategy.

[0041] Among them, the advance prediction strategy is a control strategy based on the expected future behavior of the vehicle, that is, the feedforward correction value is determined according to the expected future behavior of the vehicle.

[0042] The feedback control strategy is a control strategy based on the difference between the actual output and the expected output, that is, the feedback correction value is determined by real-time monitoring of the difference between the actual yaw rate and the target yaw rate.

[0043] Among them, the synergy of the advance prediction strategy and the feedback control strategy can actively adjust the front and rear torque distribution of the vehicle when the vehicle enters a curve, so as to reduce the risk of understeering or oversteering of the vehicle during the curve; understeering refers to the gradual increase in the turning radius of the car, which can be understood as the vehicle "running outward" when turning; oversteering refers to the gradual decrease in the turning radius of the car, which can be understood as the vehicle "turning in place" when turning.

[0044] In one embodiment, the advance prediction strategy may use the lateral acceleration and the actual yaw rate to calculate the feedforward correction value.

[0045] Among them, lateral acceleration (i.e., transverse acceleration) refers to the lateral acceleration of the vehicle at the current moment. Lateral acceleration is the acceleration of the vehicle in the lateral direction, that is, the acceleration perpendicular to the vehicle's forward direction; actual yaw angular velocity refers to the yaw angular velocity of the vehicle at the current moment. The transverse angular velocity is the angular velocity of the vehicle rotating about the vertical axis (i.e., the vehicle's up and down height direction).

[0046] In one embodiment, the feedback control strategy may include a PI control strategy, for example, obtaining a feedback correction value through a PI operation of the PI control strategy according to a difference between the actual yaw rate and the target yaw rate.

[0047] The target yaw rate refers to the yaw rate that the vehicle needs to achieve, and the target yaw rate can be determined based on the driver's steering intention and the dynamic behavior of the vehicle.

[0048] Step 130: Adjust the torque distribution of the vehicle based on the feedforward correction value, the feedback correction value, and preset upper and lower limits.

[0049] The feedforward correction value and the feedback correction value are used together to adjust the distribution ratio of the vehicle torque.

[0050] Among them, the preset upper and lower limits are used to set upper and lower limits on the adjusted torque distribution ratio to prevent the target front-rear torque distribution ratio obtained after adjustment based on the adjusted torque distribution ratio from exceeding the limit and affecting the driving performance of the vehicle.

[0051] In one embodiment, a limit lookup table is pre-constructed. Since the limit lookup table contains preset upper and lower limits corresponding to different lateral acceleration conditions, the preset upper and lower limits corresponding to the lateral acceleration can be determined according to the limit lookup table.

[0052] In one embodiment, an initial correction value can be determined based on the feedforward correction value and the feedback correction value, and then the final adjusted torque distribution ratio can be determined based on the comparison result of the initial correction value and the preset upper and lower limits. Finally, the vehicle's torque distribution is adjusted based on the final adjustment value, which can prevent the final calculated target front-rear torque distribution ratio from exceeding the limit.

[0053] Thus, the vehicle torque distribution method provided by an embodiment of the present invention activates a cornering yaw control function upon detecting that the vehicle meets activation conditions; within the cornering yaw control function, determines a feedforward correction value based on an advance prediction strategy, and determines a feedback correction value based on a feedback control strategy; and adjusts the vehicle's torque distribution based on the feedforward correction value, the feedback correction value, and preset upper and lower limits. By activating the cornering yaw control function upon detecting that the vehicle meets activation conditions, the method effectively prevents false triggering and frequent activation of the cornering yaw control function. The method then combines the feedforward correction value, the feedback correction value, and the preset upper and lower limits to adjust the vehicle's torque distribution to improve the vehicle's understeer or oversteer characteristics. This method not only improves the vehicle's understeer or oversteer characteristics during cornering without changing the hardware configuration, thereby enhancing the vehicle's cornering performance, but also reduces the frequency of ESC intervention, thereby avoiding abrupt cornering sensations for the driver.

[0054] Figure 3 The flow chart of determining the feedforward correction value according to the advance prediction strategy provided by the embodiment of the present invention is shown, and the method is executed by the vehicle controller of the vehicle. Figure 3 As shown, the method includes steps 1201 to 1202:

[0055] Step 1201: Based on the advance prediction strategy, determine the lateral acceleration and actual yaw rate of the vehicle.

[0056] The lateral acceleration may be obtained by a sensor installed on the vehicle, for example, directly by a lateral acceleration sensor, or by obtaining the speed difference between the left and right wheels by a wheel speed sensor, and then determining the lateral acceleration based on the speed difference.

[0057] The actual yaw angular velocity can also be obtained by sensors installed on the vehicle, such as directly through a gyroscope, or by measuring the steering wheel rotation angle and speed through a steering angular velocity sensor, and then indirectly calculating the actual yaw angular velocity in combination with the vehicle's wheelbase.

[0058] Step 1202: Determine a feedforward correction value according to the lateral acceleration and the actual yaw rate.

[0059] In one embodiment, an advance prediction model may be set, and the lateral acceleration and the actual yaw angular velocity may be input into the advance prediction model to obtain a feedforward correction value output by the model.

[0060] In one embodiment, a feedforward lookup table may be pre-constructed. Since the feedforward lookup table includes the feedforward correction values required under different lateral accelerations and yaw angular velocities, the feedforward correction values corresponding to the lateral acceleration and the actual yaw angular velocity may be determined based on the feedforward lookup table.

[0061] Thus, the vehicle torque distribution method provided in this embodiment determines the vehicle's lateral acceleration and actual yaw rate based on an advance prediction strategy, and determines a feedforward correction value based on the lateral acceleration and actual yaw rate. This advance prediction strategy analyzes the driver's lateral acceleration and actual yaw rate to predict the vehicle's behavior in a curve. Based on this behavior, the feedforward correction value is determined to adjust the vehicle's torque distribution, thereby optimizing the vehicle's cornering attitude and effectively reducing the risk of understeer and oversteer during cornering.

[0062] Figure 4 The flow chart of determining the feedback correction value according to the feedback control strategy provided by the embodiment of the present invention is shown, and the method is executed by the vehicle controller of the vehicle. Figure 4 As shown, the method includes steps 1201' to 1204':

[0063] Step 1201 ′: determining a target yaw rate based on the current vehicle speed, wheelbase, stability factor, and current front wheel angle of the vehicle, wherein the current front wheel angle is determined according to the steering wheel angle of the vehicle.

[0064] Among them, the current vehicle speed refers to the speed of the vehicle at the current moment; the wheelbase refers to the distance between the front axle and the rear axle of the vehicle; the current front wheel angle refers to the instantaneous angle of the front wheel of the vehicle relative to the vehicle's forward direction at the current moment, which can be determined based on the steering wheel angle; the stability factor can be determined based on actual vehicle calibration.

[0065] The target yaw rate can be determined based on a linear two-degree-of-freedom vehicle model. The specific calculation formula is as follows:

[0066]

[0067] Where, ω r is the target yaw rate, δ is the current front wheel angle, u is the current vehicle speed, L is the vehicle wheelbase, and K is the stability factor.

[0068] Step 1202 ′: Determine a proportional coefficient and an integral coefficient of a feedback control strategy based on the lateral acceleration of the vehicle and the road adhesion coefficient.

[0069] Among them, the road adhesion coefficient can be obtained from ESC (electronic stability control system).

[0070] Among them, the proportional coefficient is the P term coefficient in the PI operation of the feedback control strategy, and the integral coefficient is the I term coefficient in the PI operation of the feedback control strategy.

[0071] In one embodiment, a coefficient lookup table can be pre-constructed. Since the coefficient lookup table contains proportional coefficients and integral coefficients corresponding to different lateral accelerations and road adhesion coefficients, after obtaining the lateral acceleration and road adhesion coefficient, the corresponding proportional coefficient and integral coefficient can be directly found according to the coefficient lookup table.

[0072] Step 1203 ′: Determine the difference between the target yaw rate and the actual yaw rate.

[0073] The target yaw rate refers to the yaw rate that the vehicle needs to achieve, and the actual yaw rate refers to the yaw rate of the vehicle at the current moment.

[0074] Step 1204 ′: Determine a feedback correction value according to the difference, the proportional coefficient, and the integral coefficient.

[0075] In one embodiment, the proportional part in the PI operation of the feedback control strategy can be determined based on the difference and the proportional coefficient. The proportional part is the product of the proportional coefficient and the error signal. The integral part in the PI operation of the feedback control strategy can be determined based on the difference and the integral coefficient. The integral part is the product of the integral coefficient and the integral of the error signal over time. Finally, the proportional part and the integral part are combined to obtain the feedback correction value.

[0076] Thus, the vehicle torque distribution method provided in this embodiment determines a target yaw rate based on the vehicle's current speed, wheelbase, stability factor, and current front wheel angle, where the current front wheel angle is determined based on the vehicle's steering wheel angle; determines a proportional coefficient and an integral coefficient of a feedback control strategy based on the vehicle's lateral acceleration and road adhesion coefficient; determines the difference between the target yaw rate and the actual yaw rate; and determines a feedback correction value based on the difference, the proportional coefficient, and the integral coefficient. Adjusting the vehicle's torque distribution using the feedback correction value determined by the feedback control strategy can effectively reduce yaw rate errors during cornering, ensuring that the vehicle's actual yaw rate remains stable near the target yaw rate, thereby improving the vehicle's controllability and stability.

[0077] Figure 5 The flow chart of adjusting the torque distribution of the vehicle based on the feedforward correction value, the feedback correction value and the preset upper and lower limits provided by the embodiment of the present invention is shown. The method is executed by the vehicle controller of the vehicle. The preset upper and lower limits include a preset upper limit value and a preset lower limit value, such as Figure 5 As shown, the method includes steps 1301 to 1305:

[0078] Step 1301: Determine an initial correction value according to the feedforward correction value and the feedback correction value.

[0079] The feedforward correction value and the feedback correction value may be added together to obtain the initial correction value.

[0080] Step 1302: When the initial correction value is less than or equal to the preset upper limit value and greater than or equal to the preset lower limit value, determine the initial correction value as the target correction value.

[0081] The preset upper limit value and the preset lower limit value can both be determined from a pre-built limit value lookup table.

[0082] When the initial correction value is between a preset upper limit and a preset lower limit, the torque distribution of the vehicle can be adjusted directly according to the initial correction value.

[0083] Step 1303: When the initial correction value is greater than the preset upper limit value, determine the preset upper limit value as the target correction value.

[0084] When the initial correction value is greater than the preset upper limit value, the preset upper limit value may be directly determined as the target correction value.

[0085] Step 1304: When the initial correction value is less than the preset lower limit value, determine the preset lower limit value as the target correction value.

[0086] When the initial correction value is less than the preset lower limit value, the preset lower limit value may be directly determined as the target correction value.

[0087] Step 1305: Adjust the torque distribution of the vehicle based on the target correction value.

[0088] Among them, before the vehicle's torque distribution is adjusted, the vehicle distributes the vehicle's torque according to a fixed front and rear axle torque ratio. After obtaining the target correction value, the vehicle's torque distribution can be adjusted from the fixed front and rear axle torque distribution ratio to the target front and rear axle torque distribution ratio based on the target correction value. The target front and rear axle torque distribution ratio is determined based on the fixed front and rear axle torque distribution ratio and the target correction value.

[0089] In one embodiment, Figure 6As shown, a feedforward correction value can be determined based on the actual yaw rate and the target yaw rate, and a proportional coefficient and an integral coefficient of the PI operation can be determined based on the lateral acceleration and the road adhesion coefficient. Then, a feedback correction value is calculated based on the proportional coefficient, the integral coefficient, and the difference between the target yaw rate and the actual yaw rate. The feedforward correction value and the feedback correction value are combined to determine an initial correction value. Then, a target correction value is determined based on a comparison result between the initial correction value and preset upper and lower limits. Finally, the torque distribution of the vehicle is adjusted based on the target correction value.

[0090] Thus, the vehicle torque distribution method provided in this embodiment determines an initial correction value based on the feedforward correction value and the feedback correction value; when the initial correction value is less than or equal to the preset upper limit and greater than or equal to the preset lower limit, determines the initial correction value as the target correction value; when the initial correction value is greater than the preset upper limit, determines the preset upper limit as the target correction value; when the initial correction value is less than the preset lower limit, determines the preset lower limit as the target correction value; and adjusts the vehicle torque distribution based on the target correction value. By limiting the adjusted torque distribution ratio of the vehicle torque distribution using the preset upper and lower limits, this can prevent a significant difference between the front motor torque distribution and the rear motor torque distribution, thereby affecting the vehicle's dynamic performance and handling, and can also help maintain the vehicle's stability during cornering.

[0091] Figure 7 The figure shows a flow chart of the process before the curve yaw control function is activated when the vehicle is detected to meet the activation conditions, which is provided by an embodiment of the present invention. The method is executed by the vehicle controller. Figure 7 As shown, the method includes steps 10 to 20:

[0092] Step 10: Obtain the current speed of the vehicle, current steering wheel data, available torque of the front and rear motors, and the current state of the vehicle.

[0093] Among them, the current steering wheel steering data includes the current steering wheel angle and the current steering wheel angle change rate; the available torque of the front and rear motors includes the available torque of the front motor and the available torque of the rear motor; the current state of the vehicle can be a driving state or a non-driving state, or a fault state or a non-fault state.

[0094] Step 20: When the current vehicle speed is greater than a first vehicle speed threshold, the current steering wheel steering data is greater than a first steering wheel steering threshold, the available torque of the front and rear motors is greater than a preset torque threshold, and the current state of the vehicle is a driving state and a fault-free state, determine that the vehicle meets the activation conditions.

[0095] The first steering wheel turning threshold includes a first steering wheel angle threshold and a first steering wheel angle change rate threshold.

[0096] In one embodiment, when the current steering wheel angle is greater than the first steering wheel angle threshold or the current steering wheel angle change rate is greater than the first steering wheel angle change rate, it can be determined that the current steering wheel steering data is greater than the first steering wheel steering threshold, that is, only any one condition needs to be met to determine that the current steering wheel steering data is greater than the first steering wheel steering threshold.

[0097] In one embodiment, when the available torque of the front motor is greater than a preset torque threshold and the available torque of the rear motor is greater than a preset torque threshold, it can be determined that the available torque of the front and rear motors is greater than the preset torque threshold.

[0098] Thus, the vehicle torque distribution method provided in this embodiment obtains the vehicle's current speed, current steering wheel data, available torque of the front and rear motors, and the vehicle's current state. The method determines that the vehicle meets activation conditions when the current vehicle speed is greater than a first speed threshold, the current steering wheel data is greater than a first steering wheel threshold, the available torque of the front and rear motors is greater than a preset torque threshold, and the vehicle's current state is driving and fault-free. By restricting activation conditions, the method effectively prevents false triggering and frequent activation of the cornering control function, which could affect the vehicle's drivability.

[0099] Figure 8 The flow chart of adjusting the torque distribution of the vehicle based on the feedforward correction value, the feedback correction value and the preset upper and lower limits provided by the embodiment of the present invention is shown. The method is executed by the vehicle controller of the vehicle. Figure 8 As shown, the method includes steps 210 to 220:

[0100] Step 210: When the current vehicle speed is less than a second vehicle speed threshold or the current steering wheel steering data is less than a second steering wheel steering threshold, determine that the vehicle meets the exit condition, wherein the second vehicle speed threshold is less than the first vehicle speed threshold, and the second steering wheel steering data is less than the first steering wheel steering threshold.

[0101] The current steering wheel steering data includes the current steering wheel angle and the current steering wheel angle change rate; the second steering wheel steering threshold includes the second steering wheel angle threshold and the second steering wheel angle change rate threshold.

[0102] Among them, the threshold setting of the exit condition should have hysteresis compared with the threshold setting of the activation condition. For example, the second vehicle speed threshold should be smaller than the first vehicle speed threshold, and the second steering wheel steering data should be smaller than the first steering wheel steering data. This can avoid the situation where the cornering yaw control function is exited again because the vehicle quickly meets the exit conditions after just turning on the function.

[0103] In one embodiment, when the current steering wheel angle is less than the second steering wheel angle threshold and the current steering wheel angle change rate is less than the second steering wheel angle change rate, it can be determined that the current steering wheel steering data is less than the second steering wheel steering threshold, that is, these two conditions need to be met at the same time to determine that the current steering wheel steering data is less than the second steering wheel steering threshold.

[0104] Among them, when the current steering wheel angle is less than the second steering wheel angle threshold, it can be said that the steering wheel is returned to the center or the steering wheel angle is too small. When the current steering wheel angle change rate is less than the second steering wheel angle change rate, it can be said that the driver did not steer the wheel or the steering wheel angle change rate is too small.

[0105] Step 220: When it is detected that the vehicle meets the exit condition, exit the curve yaw control function.

[0106] The exit condition is a condition for exiting the curve yaw control function, and the setting of the exit condition can be used to determine whether the vehicle still needs the curve yaw control function.

[0107] Therefore, the vehicle torque distribution method provided in this embodiment determines that the vehicle meets the exit condition when the current vehicle speed is less than a second vehicle speed threshold or the current steering wheel steering data is less than a second steering wheel steering threshold, where the second vehicle speed threshold is less than the first vehicle speed threshold and the second steering wheel steering data is less than the first steering wheel steering threshold; and upon detecting that the vehicle meets the exit condition, exiting the cornering yaw control function. This method can determine whether the vehicle meets the exit condition for the cornering yaw control function based on the vehicle's current driving information, allowing the cornering yaw control function to be promptly exited when the vehicle no longer requires yaw control, thereby quickly returning the vehicle to normal driving conditions and improving the vehicle's overall drivability.

[0108] Figure 9 A schematic diagram of a process flow after exiting the curve yaw control function when detecting that the vehicle meets the exit condition provided by an embodiment of the present invention is shown. The method is executed by the vehicle controller of the vehicle.

[0109] like Figure 9 As shown, the method includes steps 230 to 240:

[0110] Step 230: Determine a transition threshold and a time threshold.

[0111] The transition threshold refers to the maximum adjustment value for adjusting the vehicle torque, and the time threshold refers to the maximum total time spent on adjusting the vehicle torque.

[0112] Step 240: Based on the transition threshold and the time threshold, adjust the torque distribution of the vehicle according to the slope transition strategy.

[0113] Among them, the slope transition strategy refers to gradually adjusting the vehicle's torque distribution from the target front-to-rear torque distribution ratio to a fixed front-to-rear axle torque distribution ratio, that is, each adjustment is made according to a fixed adjustment value, which cannot be greater than the transition threshold, and the total time spent adjusting the vehicle torque based on the adjustment value cannot exceed the time threshold.

[0114] In one embodiment, Figure 10 The overall process diagram of vehicle torque distribution shown in the figure requires first determining the conditions for turning on the cornering yaw control function. After turning on the cornering yaw control function, the vehicle's torque distribution is adjusted, and the conditions for exiting the cornering yaw control function are determined. After exiting the yaw control function, the vehicle's torque distribution is adjusted from the target front-to-rear torque distribution ratio to a fixed front-to-rear torque distribution ratio through transition control, and finally the vehicle's longitudinal control function is realized.

[0115] Thus, the vehicle torque distribution method provided in this embodiment determines a transition threshold and a time threshold; based on the transition threshold and the time threshold, the vehicle torque distribution is adjusted according to a slope transition strategy. Setting the transition threshold prevents vehicle jerking caused by excessively large adjustments to the vehicle's torque distribution each time. Setting the time threshold also prevents prolonged torque adjustments that could affect the vehicle's drivability. Furthermore, the slope transition strategy gradually adjusts the target front-to-rear torque distribution ratio to a fixed front-to-rear torque distribution ratio, effectively preventing drivability issues.

[0116] Figure 11 FIG. 1 shows a schematic structural diagram of an embodiment of a vehicle torque distribution device according to the present invention. Figure 10 As shown, the device 300 includes: an opening module 310 , a determination module 320 and an adjustment module 330 .

[0117] The activation module 310 is configured to activate the curve yaw control function when it is detected that the vehicle meets activation conditions.

[0118] The determination module 320 is used to determine the feedforward correction value according to the advance prediction strategy and the feedback correction value according to the feedback control strategy under the curve yaw control function.

[0119] The adjustment module 330 is configured to adjust the torque distribution of the vehicle based on the feedforward correction value, the feedback correction value, and preset upper and lower limits.

[0120] In an optional manner, the determining module 320 is configured to:

[0121] Determining the lateral acceleration and actual yaw rate of the vehicle based on an advance prediction strategy;

[0122] A feedforward correction value is determined according to the lateral acceleration and the actual yaw rate.

[0123] In an optional manner, the determining module 320 is configured to:

[0124] determining a target yaw rate based on a current vehicle speed, a wheelbase, a stability factor, and a current front wheel angle of the vehicle, wherein the current front wheel angle is determined according to a steering wheel angle of the vehicle;

[0125] Determining a proportional coefficient and an integral coefficient of a feedback control strategy based on the lateral acceleration of the vehicle and the road adhesion coefficient;

[0126] determining a difference between the target yaw rate and the actual yaw rate;

[0127] A feedback correction value is determined according to the difference, the proportional coefficient, and the integral coefficient.

[0128] In an optional manner, the preset upper and lower limits include a preset upper limit value and a preset lower limit value;

[0129] The adjustment module 330 is configured to:

[0130] determining an initial correction value according to the feedforward correction value and the feedback correction value;

[0131] When the initial correction value is less than or equal to the preset upper limit value and greater than or equal to the preset lower limit value, determining the initial correction value as the target correction value;

[0132] When the initial correction value is greater than the preset upper limit value, determining the preset upper limit value as the target correction value;

[0133] When the initial correction value is less than the preset lower limit value, determining the preset lower limit value as the target correction value;

[0134] The torque distribution of the vehicle is adjusted based on the target correction value.

[0135] In an optional manner, the opening module 310 is used to:

[0136] Obtaining the current speed of the vehicle, current steering wheel data, available torque of the front and rear motors, and the current state of the vehicle;

[0137] When the current vehicle speed is greater than a first vehicle speed threshold, the current steering wheel steering data is greater than a first steering wheel steering threshold, the available torque of the front and rear motors is greater than a preset torque threshold, and the current state of the vehicle is a driving state and a fault-free state, it is determined that the vehicle meets the activation conditions.

[0138] In an optional manner, the adjustment module 330 is configured to:

[0139] When the current vehicle speed is less than a second vehicle speed threshold or the current steering wheel steering data is less than a second steering wheel steering threshold, determining that the vehicle meets an exit condition, wherein the second vehicle speed threshold is less than the first vehicle speed threshold, and the second steering wheel steering data is less than the first steering wheel steering threshold;

[0140] When it is detected that the vehicle meets the exit condition, the curve yaw control function is exited.

[0141] In an optional manner, the adjustment module 330 is configured to:

[0142] Determine transition thresholds and time thresholds;

[0143] Based on the transition threshold and the time threshold, the torque distribution of the vehicle is adjusted according to a slope transition strategy.

[0144] Thus, the vehicle torque distribution method provided by an embodiment of the present invention activates a cornering yaw control function upon detecting that the vehicle meets activation conditions; within the cornering yaw control function, determines a feedforward correction value based on an advance prediction strategy, and determines a feedback correction value based on a feedback control strategy; and adjusts the vehicle's torque distribution based on the feedforward correction value, the feedback correction value, and preset upper and lower limits. By activating the cornering yaw control function upon detecting that the vehicle meets activation conditions, the method effectively prevents false triggering and frequent activation of the cornering yaw control function. The method then combines the feedforward correction value, the feedback correction value, and the preset upper and lower limits to adjust the vehicle's torque distribution to improve the vehicle's understeer or oversteer characteristics. This method not only improves the vehicle's understeer or oversteer characteristics during cornering without changing the hardware configuration, thereby enhancing the vehicle's cornering performance, but also reduces the frequency of ESC intervention, thereby avoiding abrupt cornering sensations for the driver.

[0145] Figure 12 The schematic structural diagram of an embodiment of the vehicle of the present invention is shown, and the specific embodiment of the present invention does not limit the specific implementation of the vehicle.

[0146] like Figure 12 As shown, the vehicle may include: a processor 402 , a communications interface 404 , a memory 406 , and a communication bus 408 .

[0147] Processor 402, communication interface 404, and memory 406 communicate with each other via communication bus 408. Communication interface 404 is used to communicate with other devices, such as clients or other server network elements. Processor 402 is used to execute program 410, which may specifically perform the steps described in the aforementioned embodiment of the vehicle torque distribution method.

[0148] Specifically, the program 410 may include program code including computer-executable instructions.

[0149] Processor 402 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention. The one or more processors included in the vehicle torque distribution device may be of the same type, such as one or more CPUs, or may be of different types, such as one or more CPUs and one or more ASICs.

[0150] The memory 406 is used to store the program 410. The memory 406 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0151] The program 410 may be specifically called by the processor 402 to cause the vehicle torque distribution device to perform the following operations:

[0152] When it is detected that the vehicle meets the activation conditions, the cornering yaw control function is turned on;

[0153] Under the curve yaw control function, the feedforward correction value is determined according to the advance prediction strategy, and the feedback correction value is determined according to the feedback control strategy;

[0154] The torque distribution of the vehicle is adjusted based on the feedforward correction value, the feedback correction value, and preset upper and lower limits.

[0155] Thus, the vehicle torque distribution method provided by an embodiment of the present invention activates a cornering yaw control function upon detecting that the vehicle meets activation conditions; within the cornering yaw control function, determines a feedforward correction value based on an advance prediction strategy, and determines a feedback correction value based on a feedback control strategy; and adjusts the vehicle's torque distribution based on the feedforward correction value, the feedback correction value, and preset upper and lower limits. By activating the cornering yaw control function upon detecting that the vehicle meets activation conditions, the method effectively prevents false triggering and frequent activation of the cornering yaw control function. The method then combines the feedforward correction value, the feedback correction value, and the preset upper and lower limits to adjust the vehicle's torque distribution to improve the vehicle's understeer or oversteer characteristics. This method not only improves the vehicle's understeer or oversteer characteristics during cornering without changing the hardware configuration, thereby enhancing the vehicle's cornering performance, but also reduces the frequency of ESC intervention, thereby avoiding abrupt cornering sensations for the driver.

[0156] An embodiment of the present invention provides a computer-readable storage medium, which stores at least one executable instruction. When the executable instruction runs on a vehicle torque distribution device / apparatus, the vehicle torque distribution device / apparatus executes the vehicle torque distribution method in any of the above-mentioned method embodiments.

[0157] The algorithms or displays provided herein are not inherently related to any particular computer, virtual system or other device. In addition, the embodiments of the present invention are not directed to any particular programming language.

[0158] In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the present invention may be practiced without these specific details. Similarly, in order to streamline the present invention and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of embodiments of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. The claims that follow the detailed description are hereby expressly incorporated into that detailed description, with each claim itself serving as a separate embodiment of the present invention.

[0159] Those skilled in the art will appreciate that the modules in the devices of the embodiments can be adaptively changed and installed in one or more devices different from the embodiments. The modules, units, or components in the embodiments can be combined into one module, unit, or component, and furthermore, they can be divided into multiple submodules, subunits, or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive.

[0160] It should be noted that the above embodiments illustrate rather than limit the invention, and that alternative embodiments may be devised by a person skilled in the art without departing from the scope of the appended claims. In the claims, any reference signs placed between brackets should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention may be implemented by means of hardware comprising several different elements and by means of appropriately programmed computers. In a unit claim enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third etc. does not indicate any order. These words may be interpreted as names. The steps in the above embodiments should not be understood as limiting the order of execution unless otherwise specified.

Claims

1. A vehicle torque distribution method, characterized in that: The method comprises: When it is detected that the vehicle meets the activation conditions, the cornering yaw control function is turned on; In the cornering yaw control function, a feedforward correction value is determined according to an advance prediction strategy, and a feedback correction value is determined according to a feedback control strategy, wherein the advance prediction strategy calculates the feedforward correction value based on the lateral acceleration and the actual yaw rate based on an advance prediction model or a feedforward lookup table; adjusting the torque distribution of the vehicle based on the feedforward correction value, the feedback correction value, and preset upper and lower limits, wherein the preset upper and lower limits are determined according to a limit lookup table, the limit lookup table containing preset upper and lower limits corresponding to different lateral acceleration conditions, the preset upper and lower limits being used to set upper and lower limits on the adjusted torque distribution ratio; Determining the feedback correction value according to the feedback control strategy includes: Determining a proportional coefficient and an integral coefficient of a feedback control strategy based on the lateral acceleration of the vehicle, the road adhesion coefficient, and a coefficient lookup table; determining a difference between a target yaw rate and an actual yaw rate; A feedback correction value is determined according to the difference, the proportional coefficient, and the integral coefficient.

2. The method according to claim 1, characterized in that The step of determining the feedforward correction value according to the advance prediction strategy includes: Determining the lateral acceleration and actual yaw rate of the vehicle based on an advance prediction strategy; A feedforward correction value is determined according to the lateral acceleration and the actual yaw rate.

3. The method according to claim 1, characterized in that Before the step of determining the feedback correction value according to the feedback control strategy, the method further includes: A target yaw rate is determined based on a current vehicle speed, a wheelbase, a stability factor, and a current front wheel angle of the vehicle, wherein the current front wheel angle is determined according to a steering wheel angle of the vehicle.

4. The method according to claim 1, wherein The preset upper and lower limits include a preset upper limit and a preset lower limit; The adjusting the torque distribution of the vehicle based on the feedforward correction value, the feedback correction value, and preset upper and lower limits includes: determining an initial correction value according to the feedforward correction value and the feedback correction value; When the initial correction value is less than or equal to the preset upper limit value and greater than or equal to the preset lower limit value, determining the initial correction value as the target correction value; When the initial correction value is greater than the preset upper limit value, determining the preset upper limit value as the target correction value; When the initial correction value is less than the preset lower limit value, determining the preset lower limit value as the target correction value; The torque distribution of the vehicle is adjusted based on the target correction value.

5. The method according to claim 1, wherein The method further includes: before starting the curve yaw control function when detecting that the vehicle meets the activation condition; Obtaining the current speed of the vehicle, current steering wheel data, available torque of the front and rear motors, and the current state of the vehicle; When the current vehicle speed is greater than a first vehicle speed threshold, the current steering wheel steering data is greater than a first steering wheel steering threshold, the available torque of the front and rear motors is greater than a preset torque threshold, and the current state of the vehicle is a driving state and a fault-free state, it is determined that the vehicle meets the activation conditions.

6. The method according to claim 5, characterized in that After adjusting the torque distribution of the vehicle based on the feedforward correction value, the feedback correction value, and the preset upper and lower limits, the method further includes: When the current vehicle speed is less than a second vehicle speed threshold or the current steering wheel steering data is less than a second steering wheel steering threshold, determining that the vehicle meets an exit condition, wherein the second vehicle speed threshold is less than the first vehicle speed threshold, and the second steering wheel steering data is less than the first steering wheel steering threshold; When it is detected that the vehicle meets the exit condition, the curve yaw control function is exited.

7. The method according to claim 6, characterized in that After the step of exiting the curve yaw control function when detecting that the vehicle meets the exit condition, the method further includes: Determine transition thresholds and time thresholds; Based on the transition threshold and the time threshold, the torque distribution of the vehicle is adjusted according to a slope transition strategy.

8. A vehicle torque distribution device, characterized in that: The device comprises: An activation module is used to activate the curve yaw control function when it is detected that the vehicle meets the activation conditions; a determination module, configured to determine, under a curve yaw control function, a feedforward correction value according to an advance prediction strategy and a feedback correction value according to a feedback control strategy, wherein the advance prediction strategy is to calculate the feedforward correction value according to the lateral acceleration and the actual yaw angular velocity based on an advance prediction model or a feedforward lookup table; an adjustment module for adjusting the torque distribution of the vehicle based on the feedforward correction value, the feedback correction value, and preset upper and lower limits, wherein the preset upper and lower limits are determined according to a limit lookup table, the limit lookup table containing preset upper and lower limits corresponding to different lateral acceleration conditions, the preset upper and lower limits being used to set upper and lower limits on the adjusted torque distribution ratio; The determining module is further configured to: Determining a proportional coefficient and an integral coefficient of a feedback control strategy based on the lateral acceleration of the vehicle, the road adhesion coefficient, and a coefficient lookup table; determining a difference between a target yaw rate and an actual yaw rate; A feedback correction value is determined according to the difference, the proportional coefficient, and the integral coefficient.

9. A vehicle, characterized in that: include: A processor, a memory, a communication interface, and a communication bus, wherein the processor, the memory, and the communication interface communicate with each other via the communication bus; The memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform the operation of the vehicle torque distribution method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that The storage medium stores at least one executable instruction, and when the executable instruction is executed on the vehicle torque distribution device / apparatus, the vehicle torque distribution device / apparatus performs the operation of the vehicle torque distribution method according to any one of claims 1 to 7.

Images