Torque control method for vehicle instability, electronic equipment and storage medium

Abstract

The invention provides a torque control method for vehicle instability, electronic equipment and a storage medium, and the method comprises the steps: in a process that a vehicle runs on a separated road surface, in response to the detection of instability of a high-attachment-side wheel, releasing a part of brake torque applied to a low-attachment-side wheel until the relative acceleration of the high-attachment-side wheel is smaller than a preset slow-down threshold value, according to the method, the relative acceleration of the high-attachment-side wheel is smaller than the preset slow-down threshold value, then the residual braking torque of the low-attachment-side wheel is fixed, and after the preset holding time, the braking torque applied to the low-attachment-side wheel is increased on the basis of the residual braking torque. The method comprises the steps that firstly, the situation that the relative acceleration of the high-attachment-side wheel is smaller than the preset slow-down threshold value serves as the target, and part of the braking torque of the low-attachment-side wheel is unloaded; the remaining braking torque is kept, stable running of the high-attachment-side wheels is guaranteed, the braking torque continues to be applied to the low-attachment-side wheels after the preset keeping duration, the low-attachment-side wheels can be prevented from slipping when the vehicle runs by separating from the large accelerator on the road surface, and therefore the situation that the high-attachment-side wheels lose stability again is avoided.

Description

Technical Field

[0001] This application relates to the field of vehicle torque control technology, specifically to a torque control method, electronic device, and storage medium for vehicle instability. Background Technology

[0002] When a vehicle is on a split surface, its left and right wheels are on surfaces with different coefficients of friction, such as a dry surface on one side and an icy or wet surface on the other. This can easily lead to uneven torque distribution, causing the drive wheels to slip. Current control methods use slip ratio control as the control input for TCS (Traction Control System) control. This control strategy can apply braking to the lower-friction wheel on a split surface to address the slippage problem.

[0003] However, braking the low-touch wheel may cause the high-touch wheel to become unstable. This is because each axle is connected to a differential. According to the differential principle, the differential must follow the law of conservation of energy during operation. Considering power balance, the power from the power source to the output shaft is constant. When braking is applied to the low-touch wheel, the work done by the low-touch wheel decreases, so the work done by the high-touch wheel must increase. The high-touch wheel will be more likely to reach the ground adhesion limit, thus causing the high-touch wheel to slip. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, this application aims to provide a torque control method, electronic device and storage medium for vehicle instability, so as to solve the problem of high-attachment instability caused by low-attachment braking during driving on a separated road surface, and to ensure vehicle driving safety.

[0005] This application provides a torque control method for vehicle instability, the method comprising: During the vehicle's travel on a separated road surface, in response to the detection of instability of the vehicle's high-attachment wheel, a portion of the braking torque applied to the vehicle's low-attachment wheel is released until the relative acceleration of the high-attachment wheel is less than a preset deceleration threshold. The remaining braking torque of the low-side wheel is fixed, and after a preset holding time, the braking torque applied to the low-side wheel is increased based on the remaining braking torque.

[0006] Optionally, the method further includes: During the vehicle's journey on a separated road surface, the high-attachment side wheel of the vehicle is determined; The wheel travel data of the high-attachment side wheel is obtained, and the high-attachment side wheel is detected as unstable based on the wheel travel data.

[0007] Optionally, the wheel travel data includes the wheel speed, relative acceleration, and braking pressure difference between the high-attachment wheel and the low-attachment wheel; detecting whether the high-attachment wheel is unstable based on the wheel travel data includes: If the wheel speed is greater than a preset wheel speed threshold, the relative acceleration is greater than a preset calibration acceleration, and the braking pressure difference is greater than a preset calibration pressure difference, then it is determined that the high-attachment side wheel instability has been detected. The preset wheel speed threshold is the sum of the preset reference shaft speed and the preset calibration deviation.

[0008] Optionally, releasing a portion of the braking torque applied to the low-attachment wheels of the vehicle until the relative acceleration of the high-attachment wheels is less than a preset deceleration threshold includes: The braking torque is released according to the preset calibration torque as part of the braking torque applied to the low-side wheel of the vehicle; If the vehicle is still in a state of instability on the high-attachment side wheel, and the slip ratio of the low-attachment side wheel is greater than a preset slip ratio threshold, then the partial braking torque applied to the low-attachment side wheel of the vehicle will continue to be released at a preset slope until the relative acceleration of the high-attachment side wheel is less than a preset deceleration threshold.

[0009] Optionally, before releasing a portion of the braking torque applied to the low-tethered wheels of the vehicle, the method further includes: The original braking torque applied to the low-side wheel is recorded. The braking torque applied to the low-side wheel is increased based on the remaining braking torque, including: With the goal of ensuring that the increased braking torque does not exceed the original braking torque, the braking torque applied to the low-friction side wheel is increased based on the remaining braking torque.

[0010] Optionally, with the goal of ensuring that the increased braking torque does not exceed the original braking torque, the braking torque applied to the low-tether side wheel is increased based on the remaining braking torque, including: The reference braking torque is determined based on the original braking torque and the preset correction coefficient; The difference between the reference braking torque and the remaining braking torque is determined as the rising torque difference, and the torque rising gradient is determined according to the preset rising time and the rising torque difference; Based on the remaining braking torque, the braking torque applied to the low-adhesion wheel is increased according to the torque increase gradient and the preset rise time.

[0011] Optionally, after adding the braking torque applied to the low-side wheel to the remaining braking torque, the method further includes: In response to the detection of instability of the low-attached wheel, the braking torque applied to the low-attached wheel is increased based on the target slip ratio.

[0012] Optionally, after increasing the braking torque applied to the low-attached wheel based on the target slip ratio, the method further includes: If the instability of the high-attached wheel is detected again, a portion of the braking torque applied to the low-attached wheel of the vehicle is released until the relative acceleration of the high-attached wheel is less than a preset deceleration threshold. The remaining braking torque of the low-side wheel is fixed, and after a preset holding time, the braking torque applied to the low-side wheel is increased based on the remaining braking torque.

[0013] This application embodiment also provides an electronic device, the electronic device comprising: Processor and memory; The processor executes the steps of the torque control method for vehicle instability provided in any embodiment of this application by calling the program or instructions stored in the memory.

[0014] This application also provides a computer-readable storage medium storing a program or instructions that cause a computer to perform the steps of the torque control method for vehicle instability provided in any embodiment of this application.

[0015] In summary, this application proposes a torque control method for vehicle instability. During vehicle travel on a separated road surface, in response to the detection of instability in the high-attached wheel, this method releases a portion of the braking torque applied to the low-attached wheel until the relative acceleration of the high-attached wheel is less than a preset deceleration threshold. Then, the remaining braking torque of the low-attached wheel is fixed. After a preset holding time, the braking torque applied to the low-attached wheel is increased based on this remaining braking torque. This method first targets the relative acceleration of the high-attached wheel to be less than the preset deceleration threshold, unloading a portion of the braking torque from the low-attached wheel, and then maintaining the remaining braking torque to handle high-attached instability and ensure stable driving of the high-attached wheel. Furthermore, by continuing to apply braking torque to the low-attached wheel after the remaining braking torque has been maintained for a preset time, it can prevent the low-attached wheel from slipping when driving at high throttle on a separated road surface, thereby preventing active braking intervention on the low-attached wheel from causing high-attached wheel instability again. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a flowchart of a torque control method for vehicle instability provided in an embodiment of this application; Figure 2 This is a diagram illustrating the identification process of high-attached-side instability provided in an embodiment of this application; Figure 3 This is a schematic diagram of control after high-attachment-side instability provided in an embodiment of this application; Figure 4 This is a schematic diagram of control logic provided in an embodiment of this application; Figure 5 This is a schematic diagram of the structure of a torque control device for high-attachment side instability of a vehicle provided in an embodiment of this application; Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0018] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0019] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0020] As mentioned in the background section, in view of the problems in the prior art, this application proposes a torque control method for vehicle instability. Figure 1 This is a flowchart of a torque control method for vehicle instability provided in an embodiment of this application. See also... Figure 1 The specific torque control method for vehicle instability includes: S110. During the vehicle's travel on a separated road surface, in response to the detection of instability of the vehicle's high-attachment wheel, a portion of the braking torque applied to the vehicle's low-attachment wheel is released until the relative acceleration of the high-attachment wheel is less than a preset deceleration threshold.

[0021] The separated road surface can be a road surface with multiple coefficients of adhesion, allowing the vehicle's left and right wheels to be on surfaces with different coefficients of adhesion while driving on it. For example, while driving on the separated road surface, the vehicle's left wheel may be on a dry surface, while the right wheel may be on an icy or wet surface.

[0022] In this embodiment of the application, a high-adhesion wheel can refer to a wheel located on a road surface with a high coefficient of adhesion, and a low-adhesion wheel can refer to a wheel located on a road surface with a low coefficient of adhesion.

[0023] The reason for the instability of the high-friction side wheel is that each axle of the vehicle is connected to a differential. According to the differential principle, the differential must follow the law of conservation of energy during operation, i.e., input torque × input speed = left half-shaft torque × left half-shaft speed + right half-shaft torque × right half-shaft speed. When the vehicle is traveling on a separated road surface, the low-friction side wheel, being on a surface with a low coefficient of friction, is prone to slippage at high speeds. This triggers the intervention of the BTC (Brake Traction Control) system. The BTC system can apply braking force to the low-friction side wheel to solve the slippage problem at high speeds. However, the braking force applied to the low-friction side wheel reduces its driving force. Since the vehicle must follow the law of conservation of energy during travel, considering power balance, when the driving force of the low-friction side wheel decreases, the driving force of the high-friction side wheel increases. This means the high-friction side wheel does more work, making it easier for it to reach the road surface's adhesion limit, causing instability.

[0024] In this embodiment of the application, considering that when a vehicle is driving on a separated road surface, there may be a situation where active braking intervention is performed on the low-attachment wheel (i.e., applying braking force to the low-attachment wheel), which may cause the high-attachment wheel to become unstable, the vehicle can detect in real time whether the high-attachment wheel is unstable while driving on a separated road surface.

[0025] One method to detect whether a vehicle has experienced high-attachment instability is to first identify the high-attachment wheel and then determine whether the high-attachment wheel has become unstable.

[0026] In some implementations, the method provided in this application further includes: During the vehicle's journey on a separated road surface, the high-attachment side wheel of the vehicle is identified; the wheel travel data of the high-attachment side wheel is acquired, and the high-attachment side wheel is detected as unstable based on the wheel travel data.

[0027] Before identifying the high-tether side wheels of a vehicle, it is possible to first determine whether the vehicle is on a separated road surface. For example, the wheel speed difference and braking pressure difference between the left and right wheels of the vehicle can be obtained, and then the vehicle's separation from the road surface can be determined based on the wheel speed difference and braking pressure difference.

[0028] If the vehicle is traveling on a separated road surface, the high-tether wheels can be identified. The high-tether wheels can be determined based on the estimated braking pressure of the vehicle's left and right wheels.

[0029] After identifying the high-attached wheel of the vehicle, the vehicle can further acquire real-time wheel travel data of the high-attached wheel to determine whether the high-attached wheel is unstable.

[0030] In one example, wheel travel data includes the wheel speed, relative acceleration, and braking pressure difference between the high-tether wheel and the low-tether wheel; detecting whether the high-tether wheel is unstable based on the wheel travel data includes: If the wheel speed is greater than the preset wheel speed threshold, the relative acceleration is greater than the preset calibrated acceleration, and the braking pressure difference is greater than the preset calibrated pressure difference, then it is determined that the high-attachment wheel instability has been detected.

[0031] Specifically, when the wheel speed of the high-attached wheel is greater than a preset wheel speed threshold, the relative acceleration of the high-attached wheel is greater than a preset calibration acceleration, and the braking pressure difference between the high-attached wheel and the low-attached wheel is greater than a preset calibration pressure difference, the high-attached wheel is determined to be unstable.

[0032] The preset wheel speed threshold is the sum of the preset reference axle speed and the preset calibration deviation. The relative acceleration of the high-attachment wheel can be the acceleration of the high-attachment wheel relative to the vehicle's center of gravity. The braking pressure difference between the high-attachment wheel and the low-attachment wheel can be the difference between the estimated braking pressure of the high-attachment wheel and the estimated braking pressure of the low-attachment wheel.

[0033] For example, Figure 2 This is a diagram illustrating the identification process of high-attached-side instability provided in an embodiment of this application, such as... Figure 2 As shown, firstly, the high-attachment side wheel of the vehicle is identified. Secondly, the high-attachment side wheel instability is determined when all of the following conditions are met, and the high-attachment side instability flag is activated: 1. The wheel speed of the high-attachment side wheel is greater than the preset reference axle speed plus the preset calibration deviation; 2. The relative acceleration of the high-attachment side wheel is greater than the preset calibration acceleration; 3. The braking pressure difference is greater than the preset calibration pressure difference.

[0034] The above example identifies high-attached side instability by using the wheel speed, relative acceleration, and braking pressure difference between the high-attached side wheel and the low-attached side wheel. This ensures the accuracy of high-attached side instability identification and thus guarantees the reliability of subsequent torque control for high-attached side instability.

[0035] In this embodiment of the application, if it is detected that the high-attached wheel is unstable while the vehicle is driving on a separated road surface, the braking torque applied to the low-attached wheel can be unloaded first to increase the driving force of the low-attached wheel, thereby reducing the driving force of the high-attached wheel and achieving the purpose of alleviating the instability of the high-attached wheel until the relative acceleration of the high-attached wheel is less than the preset deceleration threshold, that is, the unstable high-attached wheel is pulled back to a steady state.

[0036] For example, the braking torque that causes the high-attachment wheel to become unstable can be recorded, that is, the original braking torque applied to the low-attachment wheel when the high-attachment wheel becomes unstable; then, a target release value is determined by multiplying the original braking torque by a preset ratio; a release rate is determined based on the target release value and a preset duration; and the original braking torque applied to the low-attachment wheel is continuously unloaded according to the release rate until the unloaded value reaches the target release value.

[0037] In this embodiment of the application, in order to improve the release efficiency and achieve rapid stabilization of the high-attachment wheel during the release of braking torque, the release process of braking torque can be divided into two stages: first, a portion of the braking torque is quickly unloaded, and then a portion of the torque is slowly unloaded according to a certain gradient.

[0038] In one specific implementation, releasing a portion of the braking torque applied to the low-attached wheels of the vehicle until the relative acceleration of the high-attached wheels is less than a preset deceleration threshold includes the following steps: Step 11: Release a portion of the braking torque applied to the low-impact wheel of the vehicle according to the preset calibration torque; Step 12: If the vehicle is still instability on the high-attachment side wheel and the slip ratio of the low-attachment side wheel is greater than the preset slip ratio threshold, then continue to release part of the braking torque applied to the low-attachment side wheel of the vehicle according to the preset slope until the relative acceleration of the high-attachment side wheel is less than the preset deceleration threshold.

[0039] In step 11, a preset calibration torque can be directly released from the original braking torque applied to the low-touch side wheels of the vehicle. This preset calibration torque can be a pre-set fixed value, or it can be calculated based on the original braking torque. For example, the preset calibration torque can be calculated from the original braking torque according to a pre-set ratio.

[0040] Specifically, after directly unloading part of the braking torque, it is possible to further re-detect whether the high-attached wheel is unstable, and determine whether the slip ratio of the low-attached wheel is greater than the preset slip ratio threshold.

[0041] In step 12, if the vehicle is still in a state of instability on the high-attachment side wheel and the slip ratio of the low-attachment side wheel is greater than the preset slip ratio threshold, it means that there is still instability on the high-attachment side wheel and the slip ratio of the low-attachment side wheel is still relatively high. Based on the remaining braking torque of the low-attachment side wheel, a portion of the braking torque of the low-attachment side wheel can continue to be released according to the preset slope.

[0042] During the process of releasing part of the braking torque of the low-attached wheel according to the preset slope, the relative acceleration of the high-attached wheel can be detected in real time. If the relative acceleration of the high-attached wheel is less than the preset deceleration threshold, it means that the instability of the high-attached wheel has slowed down to a certain extent (this deceleration degree is related to the preset deceleration threshold, which can be set according to actual needs). At this time, the unloading of the braking torque of the low-attached wheel can be stopped.

[0043] Through steps 11-12 above, the unloading of braking torque on the low-attachment wheel can be divided into two stages: a single release stage and a slow release stage. In the single release stage, a portion of the braking torque is unloaded directly, which can improve the braking torque release efficiency and thus achieve the goal of quickly stabilizing the high-attachment wheel. In the slow release stage, a portion of the braking torque is gradually unloaded according to the slope, which can ensure the stability of the low-attachment wheel during the torque release process and avoid excessive unloading at one time, which could cause the low-attachment wheel to slip.

[0044] S120: Fix the remaining braking torque of the low-side wheel, and after a preset holding time, increase the braking torque applied to the low-side wheel based on the remaining braking torque.

[0045] After releasing part of the braking torque of the low-side wheel with the goal of reducing the relative acceleration of the high-side wheel to a preset deceleration threshold, the remaining braking torque of the low-side wheel can be fixed until the fixed time reaches the preset holding time, so as to stabilize the high-side wheel.

[0046] Furthermore, after the high-attachment wheel stabilizes, i.e. after the preset holding time, in order to prevent the low-attachment wheel from slipping again due to excessive braking torque unloading, the braking torque applied to the low-attachment wheel can continue to be increased based on the remaining braking torque of the low-attachment wheel. This aims to increase the braking torque of the low-attachment wheel, ensuring the stability of the high-attachment wheel while minimizing slippage of the low-attachment wheel due to the low road surface coefficient. It also prevents excessive unloading of the braking torque of the low-attachment wheel, which could lead to a sudden increase in braking torque after BTC intervention, causing the high-attachment wheel to become unstable again.

[0047] In this embodiment of the application, in order to avoid the high-side wheel from becoming unstable again due to excessive increase in braking torque during the process of increasing the braking torque of the low-side wheel, the braking torque of the low-side wheel can be increased slowly with the goal of not exceeding the original braking torque.

[0048] In one specific implementation, before releasing a portion of the braking torque applied to the low-side wheel of the vehicle, the method further includes: recording the original braking torque applied to the low-side wheel. The braking torque applied to the low-side wheel is increased based on the remaining braking torque, including: With the goal of increasing the braking torque to no more than the original braking torque, the braking torque applied to the low-friction side wheel is increased based on the remaining braking torque.

[0049] Specifically, when high-attachment-side instability is detected, the original braking torque applied to the low-attachment-side wheel at that time can be recorded in a timely manner. This original braking torque can be understood as the braking torque that caused high-attachment-side instability.

[0050] After the remaining braking torque of the fixed low-friction side wheel reaches the preset holding time, the braking torque of the low-friction side wheel can be increased based on the remaining braking torque, with the goal of the increased braking torque not exceeding the original braking torque.

[0051] Through the above implementation method, during the process of increasing the braking torque of the low-attachment wheel, the increased braking torque can be limited by the recorded original braking torque, so as to avoid excessive increase in braking torque causing the high-attachment wheel to become unstable again. At the same time, it can also prevent the low-attachment wheel from slipping, thus ensuring the stability of the low-attachment wheel and the high-attachment wheel.

[0052] In this embodiment, considering that after increasing the braking torque of the low-flying wheel, the BTC system may intervene to continue applying braking torque to resolve the slippage of the low-flying wheel, in order to avoid the increased braking torque due to the intervention of the BTC system exceeding the original braking torque and thus continuing to cause instability of the high-flying wheel, the original braking torque can be reduced by a certain scale. The original braking torque after reduction is used as a limit to increase the braking torque of the low-flying wheel, thus avoiding the torque reaching the original braking torque due to the intervention of the BTC system.

[0053] In one example, with the goal of increasing the braking torque to no more than the original braking torque, the braking torque applied to the low-tether wheel is increased based on the remaining braking torque, including the following steps: Step 21: Determine the reference braking torque based on the original braking torque and the preset correction coefficient; Step 22: Determine the difference between the reference braking torque and the remaining braking torque as the rising torque difference, and determine the torque rising gradient according to the preset rising time and the rising torque difference; Step 23: Based on the remaining braking torque, increase the braking torque applied to the low-adhesion side wheel according to the torque increase gradient and preset increase time.

[0054] In step 21, a preset correction coefficient can be multiplied by the original braking torque to reduce the original braking torque and obtain a reference braking torque. The preset correction coefficient is less than 1.

[0055] Furthermore, in step 22, the difference between the reference braking torque and the remaining braking torque can be calculated to obtain the rising torque difference, which can be understood as the adjustable amount of the braking torque; then, the torque rising gradient is calculated based on the preset rising time and the rising torque difference. The preset rising time can be the duration for which the braking torque is gradually increased according to the gradient, and the torque rising gradient can reflect the magnitude of the increased braking torque in each control cycle. The control cycle can be the period in which the braking torque is increased according to the gradient, that is, the braking torque is increased according to the torque rising gradient at each control cycle interval.

[0056] For example, the torque rise gradient can be calculated based on the following formula: ; In the formula, For torque gradient, To preset the ascent time, To control the cycle, For the difference in rising torque, , To record the original braking torque, This is a preset correction factor. This represents the remaining braking torque.

[0057] After calculating the torque rise gradient, in step 23, the braking torque can be increased according to the torque rise gradient at each control cycle based on the remaining braking torque, until the increase time reaches the preset rise time.

[0058] Through steps 21-23 above, the original braking torque can be reduced, the torque rise gradient can be calculated based on the reduced original braking torque, and then the braking torque of the low-attachment wheel can be slowly increased according to the torque rise gradient. This can prevent the torque from exceeding the original braking torque due to the subsequent intervention of the BTC system, and can also prevent the torque from being increased too much at once by the subsequent intervention of the BTC system, thus further ensuring the stability of the low-attachment wheel and the high-attachment wheel.

[0059] For example, Figure 3 This is a schematic diagram of control after high-attachment-side instability provided in an embodiment of this application, such as... Figure 3 As shown, the horizontal axis represents time (in seconds), and the vertical axis represents the braking torque of the low-attachment wheel (in N×m). When the high-attachment wheel is detected to be unstable, the control after the low-attachment braking causes the high-attachment wheel to become unstable can be divided into four stages: the initial release stage, the slow release stage, the holding stage, and the slow rise stage.

[0060] like Figure 3 As shown, in the first release phase, a portion of the braking torque can be unloaded at once; in the slow release phase, a portion of the braking torque can be unloaded at a slope; in the holding phase, the remaining braking torque can be fixed; and in the slow rise phase, the braking torque can be increased at a slope, with the increased braking torque not exceeding the original braking torque that would cause instability on the high-adjacent side.

[0061] Figure 4 This is a control logic diagram provided in an embodiment of this application, such as... Figure 4 As shown, high-adhesion side instability can be identified based on wheel travel data. High-adhesion side instability identification includes identifying the high-adhesion side, determining high-adhesion side instability, and high-adhesion memory. High-adhesion memory refers to recording the low-adhesion side braking torque that caused high-adhesion side instability. After identifying high-adhesion side instability, high-adhesion side instability torque control can be performed based on the high-adhesion side instability indicator and the original braking torque from the high-adhesion side instability memory. This control includes four processes: partially unloading the braking torque, partially unloading the braking torque according to the slope, maintaining the torque, and increasing the braking torque according to the slope. The braking torque in each process can be sent to the BTC system for execution via BTC request torque.

[0062] In this embodiment of the application, considering that after the high-attachment side becomes unstable, some of the braking torque of the low-attachment side wheel is unloaded and the torque is slowly increased, the increased torque is less than the original braking torque, which may cause the low-attachment side wheel to slip. Therefore, after the high-attachment side instability control is performed, it is also possible to continue to detect whether the low-attachment side wheel is slipping, so as to perform torque control according to the slip ratio.

[0063] In some embodiments, after adding the braking torque applied to the low-side wheel to the remaining braking torque, the method further includes: In response to the detection of instability of the low-side wheel, the braking torque applied to the low-side wheel is increased based on the target slip ratio.

[0064] Specifically, after applying braking torque to the low-side wheel, the relative acceleration of the low-side wheel can be used to detect whether the low-side wheel is unstable in real time. If the low-side wheel is detected to be unstable, the braking torque applied to the low-side wheel can be increased according to the target slip ratio.

[0065] The target slip ratio is the desired slip ratio. Specifically, the real-time slip ratio of the low-side wheel can be calculated based on the reference vehicle speed and the wheel speed of the low-side wheel. Then, based on the deviation between the real-time slip ratio and the target slip ratio, the required increase in braking torque can be determined.

[0066] For example, a PID controller (Proportional-Integral-Derivative Controller) can be used to calculate the required braking torque based on the deviation between the real-time slip ratio and the target slip ratio. Here, P (proportional) indicates that the larger the deviation, the greater the required braking torque; I (integral) indicates that if the deviation persists (i.e., a steady-state deviation exists), the integral term will gradually accumulate, increasing the control output until the deviation is eliminated; and D (derivative) indicates adjustment based on the rate of change of the deviation.

[0067] In PID control, the braking torque output can be adjusted by incorporating system gain. System gain describes the amplification factor relationship between the input and output; the input is the braking torque output by the PID controller, and the output is the change in slip ratio resulting from applying that braking torque. Specifically, the actual system gain can be estimated online by detecting the relationship between the slip ratio change rate and the braking torque change rate, and then the braking torque output by the PID controller can be adjusted accordingly. Furthermore, the braking torque output by the PID controller can also be adjusted by considering the relative acceleration difference between the high-attached and low-attached wheels.

[0068] Through the above implementation method, after the high-attachment wheel stabilizes, it is possible to continue to detect whether the low-attachment wheel continues to slip. If so, torque control of the low-attachment wheel is performed based on the target slip ratio, which further ensures the stability of the low-attachment and high-attachment wheels.

[0069] Considering that after torque control is applied to the low-attachment wheel based on the target slip ratio, the high-attachment wheel may become unstable again due to excessive braking torque, it is possible to re-detect and address the high-attachment instability.

[0070] In one example, after increasing the braking torque applied to the low-side wheel based on the target slip ratio, the method further includes: If instability of the high-attached wheel is detected again, a portion of the braking torque applied to the low-attached wheel of the vehicle is released until the relative acceleration of the high-attached wheel is less than a preset deceleration threshold. The remaining braking torque of the fixed low-side wheel is increased to the braking torque applied to the low-side wheel after a preset holding time.

[0071] Specifically, after the target slip ratio is increased to the braking torque applied to the low-attached wheel, the wheel travel data of the high-attached wheel can be reacquired to determine whether the high-attached wheel is unstable.

[0072] If instability of the high-attached wheel is detected again, the original braking torque of the low-attached wheel is recorded again, and then a portion of the braking torque is released from the original braking torque until the relative acceleration of the high-attached wheel is less than the preset deceleration threshold. This release process can be divided into two stages: a single release stage and a slow release stage.

[0073] Furthermore, it can enter the holding phase, where the remaining braking torque of the low-adhesion wheel is fixed according to the preset holding time. After the preset holding time, it can enter the slow increase phase, where the braking torque of the low-adhesion wheel is slowly increased according to a certain gradient based on the remaining braking torque.

[0074] The above example demonstrates how, after controlling the low-side wheel torque according to the target slip ratio, the high-side instability caused by excessive braking torque on the low-side wheel can be resolved, further ensuring the vehicle's stability and thus guaranteeing driving safety.

[0075] The torque control method for vehicle instability provided in this application embodiment, during the process of a vehicle traveling on a separated road surface, in response to the detection of instability of the high-attached wheel, releases part of the braking torque applied to the low-attached wheel until the relative acceleration of the high-attached wheel is less than a preset deceleration threshold, thereby fixing the remaining braking torque of the low-attached wheel. After a preset holding time, the braking torque applied to the low-attached wheel is increased based on the remaining braking torque. This method first targets the relative acceleration of the high-attached wheel to be less than the preset deceleration threshold, unloads part of the braking torque of the low-attached wheel, and then maintains the remaining braking torque to handle the instability of the high-attached wheel, ensuring the stable driving of the high-attached wheel. Furthermore, after the remaining braking torque is maintained for a preset time, the braking torque is continued to be applied to the low-attached wheel, which can prevent the low-attached wheel from slipping when driving at high throttle on a separated road surface, thereby avoiding the active braking intervention of the low-attached wheel from causing the high-attached wheel to become unstable again.

[0076] Figure 5 This is a schematic diagram of a torque control device for high-attachment side instability of a vehicle provided in an embodiment of this application. The device includes a torque unloading module 510, a torque fixing module 520, and a torque increasing module 530, wherein: The torque unloading module 510 is used to release part of the braking torque applied to the low-attached wheel of the vehicle in response to the detection of instability of the high-attached wheel of the vehicle while the vehicle is traveling on a separated road surface, until the relative acceleration of the high-attached wheel is less than a preset deceleration threshold. Torque fixing module 520 is used to fix the remaining braking torque of the low-attached wheel; The torque boosting module 530 is used to increase the braking torque applied to the low-touch side wheel based on the remaining braking torque after a preset holding time.

[0077] Based on the above embodiments, optionally, the device further includes a high-attachment instability detection module, which is used to determine the high-attachment side wheel of the vehicle during the process of the vehicle driving on a separated road surface; acquire the wheel driving data of the high-attachment side wheel; and detect whether the high-attachment side wheel is unstable based on the wheel driving data.

[0078] Based on the above embodiments, optionally, the wheel travel data includes the wheel speed, relative acceleration, and braking pressure difference between the high-attachment wheel and the low-attachment wheel; the high-attachment instability detection module is further configured to determine that the high-attachment wheel instability is detected if the wheel speed is greater than a preset wheel speed threshold, the relative acceleration is greater than a preset calibration acceleration, and the braking pressure difference is greater than a preset calibration pressure difference. The preset wheel speed threshold is the sum of the preset reference shaft speed and the preset calibration deviation.

[0079] Based on the above embodiments, optionally, the torque unloading module 510 includes a primary unloading unit and a slow unloading unit, wherein: A primary unloading unit is used to release a portion of the braking torque applied to the low-side wheels of the vehicle according to a preset calibrated torque. The slow unloading unit is used to continue releasing a portion of the braking torque applied to the low-side wheels of the vehicle at a preset slope if the vehicle is still in a state of instability on the high-side wheel and the slip ratio of the low-side wheel is greater than a preset slip ratio threshold, until the relative acceleration of the high-side wheel is less than a preset deceleration threshold.

[0080] Optionally, based on the above embodiments, the device may further include a high-attachment memory module, which is used to record the original braking torque applied to the low-attachment side wheel; and a torque increase module 530, which is specifically used to increase the braking torque applied to the low-attachment side wheel based on the remaining braking torque, with the goal of the increased braking torque not exceeding the original braking torque.

[0081] Based on the above embodiments, optionally, the torque boosting module 530 is also used for: The reference braking torque is determined based on the original braking torque and the preset correction coefficient; The difference between the reference braking torque and the remaining braking torque is determined as the rising torque difference, and the torque rising gradient is determined according to the preset rising time and the rising torque difference; Based on the remaining braking torque, the braking torque applied to the low-adhesion wheel is increased according to the torque increase gradient and the preset rise time.

[0082] Based on the above embodiments, optionally, the device further includes a slip ratio control module, which is used to increase the braking torque applied to the low-attached wheel based on a target slip ratio in response to detecting instability of the low-attached wheel.

[0083] Based on the above embodiments, optionally, the device further includes a high-attachment readjustment module, which is used to release part of the braking torque applied to the low-attachment wheel of the vehicle if the high-attachment side wheel instability is detected again, until the relative acceleration of the high-attachment side wheel is less than a preset deceleration threshold; fix the remaining braking torque of the low-attachment side wheel, and after a preset holding time, increase the braking torque applied to the low-attachment side wheel based on the remaining braking torque.

[0084] The torque control device for high-adhesion side instability of vehicles provided in this application embodiment can execute the steps in the torque control method for vehicle instability provided in this application method embodiment, and has the execution steps and beneficial effects, which will not be repeated here.

[0085] Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. For example... Figure 6 As shown, the electronic device 400 includes one or more processors 401 and memory 402.

[0086] The processor 401 may be a central processing unit (CPU) or other form of processing unit with data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device 400 to perform desired functions.

[0087] The memory 402 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 401 may execute the program instructions to implement the vehicle instability torque control method of any embodiment of this application described above, and / or other desired functions. Various contents such as initial extrinsic parameters and thresholds may also be stored in the computer-readable storage medium.

[0088] In one example, the electronic device 400 may further include an input device 403 and an output device 404, these components being interconnected via a bus system and / or other forms of connection mechanisms (not shown). The input device 403 may include, for example, a keyboard, a mouse, etc. The output device 404 may output various information to the outside, including warning messages, braking force, etc. The output device 404 may include, for example, a display, a speaker, a printer, and a communication network and its connected remote output devices, etc.

[0089] Of course, for the sake of simplicity, Figure 6 Only some of the components of the electronic device 400 relevant to this application are shown in this illustration; components such as buses, input / output interfaces, etc., are omitted. In addition, the electronic device 400 may include any other suitable components depending on the specific application.

[0090] In addition to the methods and devices described above, embodiments of this application may also be computer program products, which include computer program instructions that, when executed by a processor, cause the processor to perform the steps of the torque control method for vehicle instability provided in any embodiment of this application.

[0091] The computer program product can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of this application. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0092] Furthermore, embodiments of this application may also be computer-readable storage media storing computer program instructions thereon, which, when executed by a processor, cause the processor to perform the steps of the torque control method for vehicle instability provided in any embodiment of this application.

[0093] The computer-readable storage medium may be any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof.

[0094] It should be noted that the terminology used in this application is for the purpose of describing specific embodiments only and is not intended to limit the scope of this application. As shown in the specification and claims of this application, unless the context clearly indicates otherwise, words such as "a," "an," "an," and / or "the" do not specifically refer to the singular and may also include the plural. The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, or apparatus. Without further limitations, an element defined by the phrase "comprising an..." does not exclude the presence of other identical elements in the process, method, or apparatus that includes said element.

[0095] It should also be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," "linked," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0096] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A torque control method for vehicle instability, characterized in that, include: During the vehicle's travel on a separated road surface, in response to the detection of instability of the vehicle's high-attachment wheel, a portion of the braking torque applied to the vehicle's low-attachment wheel is released until the relative acceleration of the high-attachment wheel is less than a preset deceleration threshold. The remaining braking torque of the low-side wheel is fixed, and after a preset holding time, the braking torque applied to the low-side wheel is increased based on the remaining braking torque.

2. The method according to claim 1, characterized in that, The method further includes: During the vehicle's journey on a separated road surface, the high-attachment side wheel of the vehicle is determined; The wheel travel data of the high-attachment side wheel is obtained, and the high-attachment side wheel is detected as unstable based on the wheel travel data.

3. The method according to claim 2, characterized in that, The wheel travel data includes the wheel speed, relative acceleration, and braking pressure difference between the high-side wheel and the low-side wheel. Detecting whether the high-tether side wheel is unstable based on the wheel travel data includes: If the wheel speed is greater than a preset wheel speed threshold, the relative acceleration is greater than a preset calibration acceleration, and the braking pressure difference is greater than a preset calibration pressure difference, then it is determined that the high-attachment side wheel instability has been detected. The preset wheel speed threshold is the sum of the preset reference shaft speed and the preset calibration deviation.

4. The method according to claim 1, characterized in that, Releasing a portion of the braking torque applied to the low-attached wheels of the vehicle until the relative acceleration of the high-attached wheels is less than a preset deceleration threshold includes: The braking torque is released according to the preset calibration torque as part of the braking torque applied to the low-side wheel of the vehicle; If the vehicle is still in a state of instability on the high-attachment side wheel, and the slip ratio of the low-attachment side wheel is greater than a preset slip ratio threshold, then the partial braking torque applied to the low-attachment side wheel of the vehicle will continue to be released at a preset slope until the relative acceleration of the high-attachment side wheel is less than a preset deceleration threshold.

5. The method according to claim 1, characterized in that, Before releasing a portion of the braking torque applied to the low-side wheels of the vehicle, the process also includes: The original braking torque applied to the low-side wheel is recorded. The braking torque applied to the low-side wheel is increased based on the remaining braking torque, including: With the goal of ensuring that the increased braking torque does not exceed the original braking torque, the braking torque applied to the low-friction side wheel is increased based on the remaining braking torque.

6. The method according to claim 5, characterized in that, With the goal of increasing the braking torque to no more than the original braking torque, the braking torque applied to the low-tether side wheel is increased based on the remaining braking torque, including: The reference braking torque is determined based on the original braking torque and the preset correction coefficient; The difference between the reference braking torque and the remaining braking torque is determined as the rising torque difference, and the torque rising gradient is determined according to the preset rising time and the rising torque difference; Based on the remaining braking torque, the braking torque applied to the low-adhesion wheel is increased according to the torque increase gradient and the preset rise time.

7. The method according to claim 1, characterized in that, After adding the braking torque applied to the low-side wheel to the remaining braking torque, the method further includes: In response to the detection of instability of the low-attached wheel, the braking torque applied to the low-attached wheel is increased based on the target slip ratio.

8. The method according to claim 7, characterized in that, After increasing the braking torque applied to the low-side wheel based on the target slip ratio, the method further includes: If the instability of the high-attached wheel is detected again, a portion of the braking torque applied to the low-attached wheel of the vehicle is released until the relative acceleration of the high-attached wheel is less than a preset deceleration threshold. The remaining braking torque of the low-side wheel is fixed, and after a preset holding time, the braking torque applied to the low-side wheel is increased based on the remaining braking torque.

9. An electronic device, characterized in that, The electronic device includes: Processor and memory; The processor executes the steps of the torque control method for vehicle instability as described in any one of claims 1 to 8 by calling the program or instructions stored in the memory.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a program or instructions that cause a computer to perform the steps of the torque control method for vehicle instability as described in any one of claims 1 to 8.

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