Driving anti-skid control method for four-wheel-drive vehicle, vehicle controller and storage medium

Abstract

The invention provides a four-wheel-drive vehicle driving anti-skid control method, a vehicle controller and a readable storage medium. The method comprises the steps that torque required by a driver is obtained; according to the torque required by the driver and a preset torque distribution strategy, a front shaft distribution driving torque distributed to a front driving shaft and a rear shaft distribution driving torque distributed to a rear driving shaft are determined; the front axle distributed driving torque and the rear axle distributed driving torque are slowed down in real time according to a preset torque rising slowing-down algorithm, so that the current front axle slowed-down rear driving torque and the current rear axle slowed-down rear driving torque are obtained; and controlling the four-wheel-drive vehicle according to the current front axle slowed-down rear driving torque and the current rear axle slowed-down rear driving torque. Under the condition that a driver does not actively adjust a driving pedal, continuous sliding rotation of the double shafts of the vehicle can be actively restrained, control over the vehicle tends to be stable, and the safety and driving performance of the vehicle are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of four-wheel drive vehicle control, and in particular to a four-wheel drive vehicle driving anti-skid control method, a vehicle controller and a readable storage medium. Background Art

[0002] With the rapid development of electric vehicles, electric four-wheel drive with independent drive motors on the front and rear drive axles of the vehicle has become a very typical solution. However, since the front and rear motors are mechanically decoupled and take independent torque commands, when the vehicle starts with a large torque on a low-adhesion road or drives on a road with a rapid change in adhesion, single-axis or dual-axis asynchronous slip often occurs, thus affecting the vehicle's driving stability or causing driving difficulties. In order to solve the vehicle control state in this situation, the main strategies of the current vehicle control system are as follows:

[0003] When the vehicle slips, the ESP (Electronic Stability Control System) / TCS (Traction Control System) in the chassis system is responsible for implementing the torque reduction command. For electric dual-axle drive vehicles, the VCU (Vehicle Controller) usually calculates the torque transfer strategy between the front and rear axles, but the current control strategy has the following problems:

[0004] 1. Torque reduction of the chassis system is a passive adjustment. Not only does it cause delays in multiple controllers, but the rapid torque intervention also results in poor driving comfort and smoothness.

[0005] 2. Compared with traditional internal combustion engine vehicles, electric motors have greater and faster torque output. Usually, if an electric vehicle has excellent power on a good adhesion road, its driving torque characteristics are far greater than the sum of the adhesion of the low adhesion road. Therefore, the front and rear axles will slip back and forth alternately or slip at the same time simply through torque transfer, making it difficult for the driver to operate and control.

[0006] 3. Due to the complexity and mutation of actual road conditions, the pre-controlled and set isolated power system and drive system control parameters belong to their own open-loop control, which is difficult to have good adaptability on all road surfaces.

[0007] It should be noted that the information disclosed in the background technology section of the invention is only intended to deepen the understanding of the general background technology of the invention, and should not be regarded as an admission or suggestion in any form that the information constitutes prior art already known to those skilled in the art. Summary of the invention

[0008] The purpose of the present invention is to provide a four-wheel drive vehicle anti-skid control method, a vehicle controller and a readable storage medium, which can actively suppress the continuous slip of the vehicle's two axles without the driver actively adjusting the driving pedal, so that the vehicle control tends to be stable and the vehicle's safety and driving performance are guaranteed.

[0009] To achieve the above object, the present invention provides a four-wheel drive vehicle anti-skid control method, the control method comprising:

[0010] Obtaining the driver's required torque;

[0011] Determining a front axle drive torque allocated to a front drive shaft and a rear axle drive torque allocated to a rear drive shaft according to the driver's required torque and a preset torque distribution strategy;

[0012] The front axle distributed driving torque and the rear axle distributed driving torque are slowed down in real time according to a preset torque increase slowdown algorithm to obtain a current front axle slowdown rear driving torque and a current rear axle slowdown rear driving torque, and the four-wheel drive vehicle is controlled according to the current front axle slowdown rear driving torque and the current rear axle slowdown rear driving torque.

[0013] Optionally, the preset torque distribution strategy is to transfer the driving torque of the one with a higher rotation speed between the front drive shaft and the rear drive shaft to the one with a lower rotation speed.

[0014] Optionally, the real-time deceleration processing of the front axle allocated driving torque according to a preset deceleration torque increase algorithm to obtain the current front axle deceleration rear driving torque includes:

[0015] Determine whether the preset front axle mitigation parameter correction trigger condition is currently met;

[0016] If satisfied, the front axle mitigation parameter is corrected according to the current slip parameter of the front drive axle to obtain the current front axle corrected mitigation parameter;

[0017] The front axle allocated driving torque is slowed down according to the current front axle modified slowdown parameter to obtain the current front axle slowed down driving torque.

[0018] Optionally, the real-time slowing down of the rear axle distributed driving torque according to a preset slowing down torque increase algorithm to obtain the rear axle slowing down rear driving torque includes:

[0019] Determine whether the preset rear axle deceleration parameter correction trigger condition is currently met;

[0020] If satisfied, the rear axle mitigation parameter is corrected according to the current slip parameter of the rear drive axle to obtain the current rear axle corrected mitigation parameter;

[0021] The rear axle allocated driving torque is slowed down according to the current rear axle modified slowing down parameter to obtain the current rear axle slowed down rear driving torque.

[0022] Optionally, the slip parameter is a slip rate.

[0023] Optionally, the preset front axle deceleration parameter correction trigger condition is that the current slip rate of the front drive shaft is greater than a first preset slip rate threshold and the duration for which the slip rate of the front drive shaft is greater than the first preset slip rate threshold is equal to a first preset duration;

[0024] The preset rear axle deceleration parameter correction trigger condition is that the current slip rate of the rear drive shaft is greater than a second preset slip rate threshold and the duration for which the slip rate of the rear drive shaft is greater than the second preset slip rate threshold is equal to a second preset duration.

[0025] Optionally, the correcting the front axle mitigation parameter according to the current slip parameter of the front drive shaft to obtain the current front axle corrected mitigation parameter includes:

[0026] determining a current front axle correction coefficient according to a current slip rate of the front drive axle;

[0027] The front axle mitigation parameter is corrected according to the current front axle correction coefficient to obtain a current front axle correction mitigation parameter.

[0028] Optionally, the modifying the rear axle mitigation parameter according to the current slip parameter of the rear drive axle to obtain the current rear axle modified mitigation parameter includes:

[0029] determining a current rear axle correction coefficient according to a current slip rate of the rear drive axle;

[0030] The rear axle mitigation parameter is corrected according to the current rear axle correction coefficient to obtain a current rear axle correction mitigation parameter.

[0031] Optionally, determining the current front axle correction coefficient according to the current slip rate of the front drive shaft includes:

[0032] A current front axle correction coefficient is determined based on the current slip rate of the front drive shaft, the first intensity factor, the first vehicle speed factor and the first accelerator pedal change rate factor, wherein the product of the first intensity factor, the first vehicle speed factor and the first accelerator pedal change rate factor is less than or equal to 1.

[0033] Optionally, determining the current rear axle correction coefficient according to the current slip rate of the rear drive axle includes:

[0034] The current rear axle correction coefficient is determined based on the current slip rate of the rear drive shaft, the second intensity factor, the second vehicle speed factor and the second accelerator pedal change rate factor, wherein the product of the second intensity factor, the second vehicle speed factor and the second accelerator pedal change rate factor is less than or equal to 1.

[0035] Optionally, the mitigation parameters include filtering parameters and gradient limiting parameters.

[0036] To achieve the above object, the present invention also provides a vehicle controller, including a processor and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, the four-wheel drive vehicle anti-skid control method described above is implemented.

[0037] To achieve the above object, the present invention further provides a readable storage medium, wherein the readable storage medium stores a computer program, and when the computer program is executed by a processor, the above-mentioned four-wheel drive vehicle drive anti-skid control method is implemented.

[0038] Compared with the prior art, the four-wheel drive vehicle anti-skid control method, vehicle controller and readable storage medium provided by the present invention have the following beneficial effects:

[0039] The four-wheel drive vehicle anti-skid control method provided by the present invention obtains the driver's required torque first, and then slows down the front axle distribution drive torque and the rear axle distribution drive torque in real time according to a preset torque increase reduction algorithm to obtain the current front axle slowed rear drive torque and the current rear axle slowed rear drive torque, and controls the four-wheel drive vehicle according to the current front axle slowed rear drive torque and the current rear axle slowed rear drive torque. Thus, by slowing down the front axle distribution drive torque and the rear axle distribution drive torque in real time according to the preset torque increase reduction algorithm, the rate of increase of the front axle drive torque and the rear axle drive torque can be reduced, so that it can not only ensure that the drive torque value can be reduced at the same time, thereby suppressing the occurrence of axle slip, but also reduce the sensitivity of the driver to adjust the torque through the accelerator pedal, reduce the driver's load, and thus improve the reliability of the vehicle. In summary, the present invention adopts a real-time slowing-down processing of the front axle distributed driving torque and the rear axle distributed driving torque according to a preset torque increase slowing-down algorithm to obtain the current front axle slowing-down rear driving torque and the current rear axle slowing-down rear driving torque, and controls the four-wheel drive vehicle according to the current front axle slowing-down rear driving torque and the current rear axle slowing-down rear driving torque. This control strategy can actively suppress the continuous slip of the vehicle's two axles without the driver actively adjusting the driving pedal, so that the control of the four-wheel drive vehicle can tend to be stable, ensuring that the four-wheel drive vehicle has good safety and driving performance.

[0040] Since the vehicle controller and readable storage medium provided by the present invention belong to the same inventive concept as the four-wheel drive vehicle anti-skid control method provided by the present invention, the vehicle controller and readable storage medium provided by the present invention at least have all the beneficial effects of the four-wheel drive vehicle anti-skid control method provided by the present invention. For details, please refer to the above description of the beneficial effects of the four-wheel drive vehicle anti-skid control method provided by the present invention. Therefore, the beneficial effects of the vehicle controller and readable storage medium provided by the present invention will not be described one by one here. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A flow chart of a four-wheel drive vehicle anti-skid control method provided by one embodiment of the present invention;

[0042] Figure 2 A closed-loop control flow chart of a four-wheel drive vehicle driving anti-skid control method provided by one embodiment of the present invention;

[0043] Figure 3 A schematic diagram of the block structure of a vehicle controller provided in accordance with one embodiment of the present invention. DETAILED DESCRIPTION

[0044] The following is a further detailed description of the four-wheel drive vehicle anti-skid control method, vehicle controller and readable storage medium proposed by the present invention in combination with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose provided by the present invention. In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, please refer to the accompanying drawings. It should be noted that the structure, proportion, size, etc. illustrated in the accompanying drawings of this specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention. Any modification of the structure, change of the proportional relationship or adjustment of the size, in the case of the same or similar effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical content disclosed by the present invention.

[0045] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements. The singular forms "a", "an" and "the" include plural objects, the term "or" is generally used in a sense including "and / or", the term "several" is generally used in a sense including "at least one", and the term "at least two" is generally used in a sense including "two or more". In addition, the terms "first", "second" and "third" are used for descriptive purposes only and are not to be understood as indicating or suggesting relative importance or implicitly indicating the number of the indicated technical features.

[0046] In addition, in the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0047] The core idea of ​​the present invention is to provide a four-wheel drive vehicle anti-skid control method, a vehicle controller and a readable storage medium, which can actively suppress the continuous slip of the vehicle's two axles without the driver actively adjusting the driving pedal, so that the vehicle control tends to be stable and the vehicle's safety and driving performance are guaranteed.

[0048] It should be noted that the anti-skid control method for a four-wheel drive vehicle provided by the present invention can be applied to a vehicle controller provided by the present invention, wherein the vehicle controller can be a hardware device with various operating systems. It should also be noted that the anti-skid control method for a four-wheel drive vehicle provided by the present invention can be applied to both pure electric four-wheel drive vehicles and hybrid four-wheel drive vehicles.

[0049] To realize the above idea, the present invention provides a four-wheel drive vehicle anti-skid control method, please refer to Figure 1 , which is a flow chart of a four-wheel drive vehicle anti-skid control method provided by one embodiment of the present invention. Figure 1 As shown, the four-wheel drive vehicle anti-skid control method provided by the present invention comprises the following steps:

[0050] Step S100: Obtain the driver's required torque.

[0051] Step S200: Determine the front axle drive torque allocated to the front drive shaft and the rear axle drive torque allocated to the rear drive shaft according to the driver's required torque and the preset torque distribution strategy.

[0052] Step S300, the front axle allocated driving torque and the rear axle allocated driving torque are slowed down in real time according to a preset torque increase slowdown algorithm to obtain a current front axle slowdown rear driving torque and a current rear axle slowdown rear driving torque, and the four-wheel drive vehicle is controlled according to the current front axle slowdown rear driving torque and the current rear axle slowdown rear driving torque.

[0053] Therefore, the present invention can reduce the rate of increase of the front axle drive torque and the rear axle drive torque by slowing down the front axle drive torque and the rear axle drive torque in real time according to the preset torque increase slowing algorithm, so as to not only ensure that the drive torque value can be reduced at the same time, thereby suppressing the occurrence of axle slippage, but also reduce the sensitivity of the driver to adjust the torque through the accelerator pedal, reduce the driver's load, and thus improve the reliability of the vehicle. In summary, the present invention adopts the method of slowing down the front axle drive torque and the rear axle drive torque in real time according to the preset torque increase slowing algorithm to obtain the current front axle slowing rear drive torque and the current rear axle slowing rear drive torque; and the control strategy of controlling the four-wheel drive vehicle according to the current front axle slowing rear drive torque and the current rear axle slowing rear drive torque can actively suppress the continuous slip of the two axles of the vehicle without the driver actively adjusting the driving pedal, so that the control of the four-wheel drive vehicle can be stabilized, and the four-wheel drive vehicle has good safety and driving performance.

[0054] It should be noted that, as can be understood by those skilled in the art, the current front axle slowing rear driving torque and the current rear axle slowing rear driving torque vary with time.

[0055] Please continue to refer to Figure 2 , which is a closed-loop control flow chart of a four-wheel drive vehicle anti-skid control method provided by one embodiment of the present invention, wherein: Figure 2The front axle in the figure indicates the front drive axle, and the rear axle indicates the rear drive axle. Figure 2 As shown, the four-wheel drive vehicle anti-skid control method provided by the present invention belongs to a closed-loop control algorithm, that is, during the control process, a preset torque increase reduction algorithm is used in real time according to actual control results to reduce the front axle distribution driving torque and the rear axle distribution driving torque.

[0056] Furthermore, the driver's demand can be analyzed and judged, that is, by collecting the accelerator pedal signal, the front and rear drive shaft speed signals and the vehicle speed signal, and comprehensively considering the vehicle's driving mode (automatic, economic, comfortable, sport), drive mode (forced two-wheel drive, priority two-wheel drive, four-wheel drive), and working mode (normal driving, acceleration, coasting, braking) to estimate the driver's demand capacity, that is, to obtain the driver's demand torque.

[0057] In some exemplary embodiments, the preset torque distribution strategy is to transfer the driving torque of the one with a larger rotation speed between the front drive shaft and the rear drive shaft to the one with a smaller rotation speed. Thus, by distributing the driving torque of the front drive shaft and the rear drive shaft according to the preset torque distribution strategy of transferring the driving torque of the one with a larger rotation speed between the front drive shaft and the rear drive shaft to the one with a smaller rotation speed, it is possible to achieve a torque reduction operation on the drive shaft with a slipping tendency, thereby ensuring that the front axle distribution driving torque and the rear axle distribution driving torque are subsequently slowed down according to the preset torque reduction increase algorithm to obtain the current front axle slowed down rear driving torque and the current rear axle slowed down rear driving torque, and when the four-wheel drive vehicle is controlled according to the current front axle slowed down rear driving torque and the current rear axle slowed down rear driving torque, the continuous slip of the two axles of the vehicle can be effectively and actively suppressed without the driver actively adjusting the driving pedal, so that the control of the vehicle tends to be stable, and the safety and driving performance of the vehicle are guaranteed.

[0058] In some exemplary embodiments, the real-time deceleration processing of the front axle distributed driving torque according to a preset deceleration torque increase algorithm to obtain the current front axle deceleration rear driving torque includes:

[0059] Determine whether the preset front axle mitigation parameter correction trigger condition is currently met;

[0060] If satisfied, the front axle mitigation parameter is corrected according to the current slip parameter of the front drive axle to obtain the current front axle corrected mitigation parameter;

[0061] The front axle allocated driving torque is slowed down according to the current front axle modified slowdown parameter to obtain the current front axle slowed down driving torque.

[0062] Thus, by correcting the front axle deceleration parameter only when the preset front axle deceleration parameter correction trigger condition is met at the current moment, frequent torque deceleration correction operations of the front drive shaft can be avoided. In addition, by first correcting the front axle deceleration parameter according to the current slip parameter of the front drive shaft to obtain the current front axle correction deceleration parameter, and then decelerating the front axle allocated driving torque according to the current front axle correction deceleration parameter to obtain the current front axle deceleration rear driving torque, the rising gradient of the driving torque of the front drive shaft can be effectively reduced, thereby effectively suppressing the occurrence of front drive shaft slip, and effectively reducing the sensitivity of the driver to adjust the torque through the accelerator pedal, and effectively improving the controllability of the vehicle.

[0063] In some exemplary embodiments, the real-time deceleration processing of the rear axle distributed driving torque according to a preset deceleration torque increase algorithm to obtain the rear axle deceleration rear driving torque includes:

[0064] Determine whether the preset rear axle deceleration parameter correction trigger condition is currently met;

[0065] If satisfied, the rear axle mitigation parameter is corrected according to the current slip parameter of the rear drive axle to obtain the current rear axle corrected mitigation parameter;

[0066] The rear axle allocated driving torque is slowed down according to the current rear axle modified slowing down parameter to obtain the current rear axle slowed down rear driving torque.

[0067] Therefore, by performing a deceleration process on the rear axle distribution driving torque only when the preset rear axle deceleration parameter correction trigger condition is met at the current moment, frequent torque deceleration operations on the rear drive shaft can be avoided, thereby avoiding the problem of poor driving comfort and smoothness caused by frequent torque intervention. In addition, by first correcting the rear axle deceleration parameter according to the current slip parameter of the rear drive shaft to obtain the current rear axle correction deceleration parameter, and then performing a deceleration process on the rear axle distribution driving torque according to the current rear axle correction deceleration parameter to obtain the current rear axle deceleration rear drive torque, the rising gradient of the rear drive shaft driving torque can be effectively reduced, which can not only effectively suppress the occurrence of rear drive shaft slip, but also effectively reduce the sensitivity of the driver to adjust the torque through the accelerator pedal, and effectively improve the controllability of the vehicle.

[0068] Please continue to refer to Figure 2 ,like Figure 2 As shown, in some exemplary embodiments, the slip parameter is the slip rate, that is, the front axle deceleration parameter is corrected according to the current slip rate of the front drive shaft to obtain the current front axle corrected deceleration parameter, and the rear axle deceleration parameter is corrected according to the current slip rate of the rear drive shaft to obtain the current rear axle corrected deceleration parameter.

[0069] Specifically, the slip rates of the front drive shaft and the rear drive shaft can be calculated according to the following formula:

[0070] Slip rate = (drive shaft speed - actual vehicle speed) / drive shaft speed * 100%

[0071] Therefore, by substituting the current shaft speed of the front drive shaft and the current actual vehicle speed into the above formula, the current slip rate of the front drive shaft can be calculated. Similarly, by substituting the current shaft speed of the rear drive shaft and the current actual vehicle speed into the above formula, the current slip rate of the rear drive shaft can be calculated.

[0072] Specifically, the actual vehicle speed can use the reference vehicle speed of the chassis system, and the front drive shaft speed can be calculated based on the front wheel speed or the front drive motor speed. If the speeds of the left front wheel and the right front wheel are not equal, the front drive shaft speed is calculated based on the front drive motor speed. Similarly, the rear drive shaft speed can be calculated based on the rear wheel speed or the rear drive motor speed. If the speeds of the left rear wheel and the right rear wheel are not equal, the rear drive shaft speed is calculated based on the rear drive motor speed. Further, the calculation result based on the front wheel speed or the front drive motor speed can be smoothed to obtain the front drive shaft speed. Similarly, the calculation result based on the rear wheel speed or the rear drive motor speed can be smoothed to obtain the rear drive shaft speed.

[0073] It should be noted that, as can be understood by those skilled in the art, Figure 2 The front axle state calculation in the formula refers to calculating the slip rate of the front axle, and the rear axle state calculation refers to calculating the slip rate of the rear axle. It should also be noted that in some other embodiments, the slip parameter may also be other parameters other than the slip rate that can characterize the slip intensity and trend of the drive shaft, for example, the slip parameter may also be acceleration.

[0074] In some exemplary embodiments, the preset front axle deceleration parameter correction trigger condition is that the current slip rate of the front drive shaft is greater than a first preset slip rate threshold and the duration for which the slip rate of the front drive shaft is greater than the first preset slip rate threshold is equal to a first preset duration.

[0075] Therefore, by triggering the correction operation of the front axle deceleration parameter only after the slip rate of the front drive shaft is greater than the first preset slip threshold and delayed for a first preset time, frequent torque deceleration correction operations of the front drive shaft can be further avoided.

[0076] It should be noted that, as those skilled in the art can understand, the present invention does not limit the specific values ​​of the first preset slip threshold and the first preset time duration, and the specific values ​​of the first preset slip threshold and the first preset time duration can be set according to actual needs.

[0077] In some exemplary embodiments, the preset rear axle deceleration parameter correction trigger condition is that the current slip rate of the rear drive shaft is greater than a second preset slip rate threshold and the duration for which the slip rate of the rear drive shaft is greater than the second preset slip rate threshold is equal to a second preset duration.

[0078] Therefore, by triggering the correction operation of the rear axle deceleration parameter only after the slip rate of the rear drive shaft is greater than the second preset slip threshold and delayed for a second preset time, frequent torque deceleration correction operations of the rear drive shaft can be further avoided.

[0079] It should be noted that, as those skilled in the art can understand, the present invention does not limit the specific values ​​of the second preset slip threshold and the second preset time length, and the specific values ​​of the second preset slip threshold and the second preset time length can be set according to actual needs.

[0080] In some exemplary embodiments, the modifying the front axle mitigation parameter according to the current slip parameter of the front drive axle to obtain the current front axle modified mitigation parameter includes:

[0081] determining a current front axle correction coefficient according to a current slip rate of the front drive axle;

[0082] The front axle mitigation parameter is corrected according to the current front axle correction coefficient to obtain a current front axle correction mitigation parameter.

[0083] Therefore, by first determining the current front axle correction coefficient according to the current slip rate of the front drive shaft, and then correcting the front axle mitigation parameter according to the current front axle correction coefficient to obtain the current front axle corrected mitigation parameter, the front axle mitigation parameter can be corrected by the front axle correction coefficient calculated in real time, and then the torque rise gradient of the front drive shaft can be adjusted in real time, thereby effectively slowing down the torque rise rate of the front drive shaft.

[0084] Further, determining the current front axle correction coefficient according to the current slip rate of the front drive shaft includes:

[0085] A current front axle correction coefficient is determined based on the current slip rate of the front drive shaft, the first intensity factor, the first vehicle speed factor and the first accelerator pedal change rate factor, wherein the product of the first intensity factor, the first vehicle speed factor and the first accelerator pedal change rate factor is less than or equal to 1.

[0086] Specifically, the front axle correction coefficient can be calculated according to the following formula:

[0087] Front axle correction coefficient = (1-slip rate) * first intensity factor * first vehicle speed factor * first accelerator pedal change rate factor

[0088] Therefore, by substituting the current slip rate of the front drive shaft, the first intensity factor, the first vehicle speed factor and the first accelerator pedal change rate factor into the above formula, the current front axle correction coefficient can be calculated.

[0089] It should be noted that, as those skilled in the art can understand, the present invention does not limit the specific values ​​of the first intensity factor, the first vehicle speed factor and the first accelerator pedal change rate factor, as long as the product of the three is less than or equal to 1.

[0090] Further, the first intensity factor is greater than 0 and less than or equal to 1. The smaller the first intensity factor is, the slower the rising gradient of the driving torque of the front driving shaft is, and vice versa, the faster the rising gradient of the driving torque of the front driving shaft is.

[0091] Furthermore, the first vehicle speed factor is greater than 0 and less than or equal to 1. The specific value of the first vehicle speed factor can be set according to actual needs to achieve correction of the vehicle speed, thereby balancing the power and safety of the four-wheel drive vehicle when driving.

[0092] Further, the first accelerator pedal change rate factor is greater than 1 and less than 10. Specifically, at a large positive pedal (accelerator pedal) change rate, the value of the first accelerator pedal change rate factor can be set relatively large to ensure the driver's intention.

[0093] In some exemplary embodiments, the modifying the rear axle mitigation parameter according to the current slip parameter of the rear drive axle to obtain the current rear axle modified mitigation parameter includes:

[0094] determining a current rear axle correction coefficient according to a current slip rate of the rear drive axle;

[0095] The rear axle mitigation parameter is corrected according to the current rear axle correction coefficient to obtain a current rear axle correction mitigation parameter.

[0096] Therefore, by first determining the current rear axle correction coefficient according to the current slip rate of the rear drive shaft, and then correcting the rear axle deceleration parameter according to the current rear axle correction coefficient to obtain the current rear axle corrected deceleration parameter, the rear axle deceleration parameter can be corrected by the rear axle correction coefficient calculated in real time, and then the torque rise gradient of the rear drive shaft can be adjusted in real time, thereby effectively slowing down the torque rise rate of the rear drive shaft.

[0097] Further, determining the current rear axle correction coefficient according to the current slip rate of the rear drive shaft includes:

[0098] The current rear axle correction coefficient is determined based on the current slip rate of the rear drive shaft, the second intensity factor, the second vehicle speed factor and the second accelerator pedal change rate factor, wherein the product of the second intensity factor, the second vehicle speed factor and the second accelerator pedal change rate factor is less than or equal to 1.

[0099] Specifically, the rear axle correction coefficient can be calculated according to the following formula:

[0100] Rear axle correction coefficient = (1-slip rate) * second intensity factor * second vehicle speed factor * second accelerator pedal change rate factor

[0101] Therefore, by substituting the current slip rate of the rear drive shaft, the second intensity factor, the second vehicle speed factor and the second accelerator pedal change rate factor into the above formula, the current rear axle correction coefficient can be calculated.

[0102] It should be noted that, as those skilled in the art can understand, the present invention does not limit the specific values ​​of the second intensity factor, the second vehicle speed factor and the second accelerator pedal change rate factor, as long as the product of the three is less than or equal to 1.

[0103] Further, the second intensity factor is greater than 0 and less than or equal to 1. The smaller the second intensity factor is, the slower the rising gradient of the driving torque of the rear driving shaft is, and vice versa, the faster the rising gradient of the driving torque of the rear driving shaft is.

[0104] Furthermore, the second vehicle speed factor is greater than 0 and less than or equal to 1. The specific value of the second vehicle speed factor can be set according to actual needs to achieve correction of the vehicle speed, thereby balancing the power and safety of the four-wheel drive vehicle when driving.

[0105] Further, the second accelerator pedal change rate factor is greater than 1 and less than 10. Specifically, at a large positive pedal (accelerator pedal) change rate, the value of the second accelerator pedal change rate factor can be set relatively large to ensure the driver's intention.

[0106] It should be noted that, as can be understood by those skilled in the art, the values ​​of the first intensity factor and the second intensity factor may be the same or different, the values ​​of the first vehicle speed factor and the second vehicle speed factor may be the same or different, and the values ​​of the first accelerator pedal change rate factor and the second accelerator pedal change rate factor may be the same or different.

[0107] In some exemplary embodiments, the mitigation parameters include filtering parameters and gradient limiting parameters. Thus, by respectively correcting the front axle filtering parameters and the front axle gradient limiting parameters according to the current front axle correction coefficient, the current front axle correction filtering parameters and the current front axle correction gradient limiting parameters can be obtained, so that the front axle distribution driving torque can be filtered (e.g., low-pass filtering, Kalman filtering, etc.) based on the current front axle correction filtering parameters, and the front axle distribution driving torque can be gradient limited based on the current front axle correction gradient limiting parameters, so that not only the rising rate of the driving torque of the front drive shaft can be effectively slowed down, but also the driving torque of the front drive shaft can be smoothed, effectively preventing the driving torque of the front drive shaft from sudden changes, and further ensuring that the four-wheel drive vehicle can travel smoothly.

[0108] Similarly, by respectively correcting the rear axle filter parameters and the rear axle gradient limit parameters according to the current rear axle correction coefficient, the current rear axle correction filter parameters and the current rear axle correction gradient limit parameters can be obtained, so that the rear axle distribution driving torque can be filtered (such as low-pass filtering, Kalman filtering, etc.) based on the current rear axle correction filter parameters, and the rear axle distribution driving torque can be gradient limited based on the current rear axle correction gradient limit parameters, which can not only effectively slow down the rising rate of the driving torque of the rear drive shaft, but also realize smooth processing of the driving torque of the rear drive shaft, effectively prevent sudden changes in the driving torque of the rear drive shaft, and further ensure that the four-wheel drive vehicle can run smoothly.

[0109] It should be noted that, as those skilled in the art can understand, the initial values ​​of the front axle filter parameter and the front axle gradient limit parameter can be determined by any feasible means such as table lookup, formula calculation, etc. Similarly, the initial values ​​of the rear axle filter parameter and the rear axle gradient limit parameter can be determined by any feasible means such as table lookup, formula calculation, etc. It should also be noted that, as those skilled in the art can understand, if the preset front axle mitigation parameter correction trigger condition is not met at present, there is no need to correct the front axle filter parameter and the front axle gradient limit parameter, that is, the front axle distribution drive torque can be directly slowed down according to the front axle filter parameter and the front axle gradient limit parameter at the previous moment. Similarly, if the preset rear axle mitigation parameter correction trigger condition is not met at present, there is no need to correct the rear axle filter parameter and the rear axle gradient limit parameter, that is, the rear axle distribution drive torque can be directly slowed down according to the rear axle filter parameter and the rear axle gradient limit parameter at the previous moment.

[0110] Based on the same inventive concept, the present invention also provides a vehicle controller, please refer to Figure 3 , which is a schematic block diagram of a vehicle controller provided by one embodiment of the present invention. Figure 3As shown, the vehicle controller includes a processor 101 and a memory 103, and a computer program is stored in the memory 103. When the computer program is executed by the processor 101, the above-mentioned four-wheel drive vehicle anti-skid control method is implemented. Since the vehicle controller provided by the present invention and the four-wheel drive vehicle anti-skid control method provided by the present invention belong to the same inventive concept, the vehicle controller provided by the present invention at least has all the beneficial effects of the four-wheel drive vehicle anti-skid control method provided by the present invention. For details, reference can be made to the above description of the beneficial effects of the four-wheel drive vehicle anti-skid control method provided by the present invention, so the beneficial effects of the vehicle controller provided by the present invention will not be repeated one by one.

[0111] like Figure 3 As shown, the vehicle controller also includes a communication interface 102 and a communication bus 104, wherein the processor 101, the communication interface 102, and the memory 103 communicate with each other through the communication bus 104. The communication bus 104 includes but is not limited to a CAN bus, etc. For ease of representation, only one thick line is used in the figure, but it does not mean that there is only one bus or one type of bus. The communication interface 102 is used for communication between the above-mentioned vehicle controller (such as a vehicle controller) and other vehicle controllers (such as a motor controller, etc., not shown in the figure). The communication bus 104 connects the above-mentioned vehicle controller (such as a vehicle controller) and other vehicle controllers (such as a motor controller, etc.) and other dispersed nodes into a closed-loop system, so that each vehicle controller can communicate and transmit data in multiple working states (parking state, charging state, starting state, running state, vehicle forward and backward state, feedback braking state, mechanical braking state, general fault state, major fault state), thereby realizing the control function of the vehicle.

[0112] Furthermore, the processor 101 referred to in the present invention may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc. The processor 101 is the control center of the vehicle controller, and various interfaces and lines are used to connect various parts of the entire vehicle controller.

[0113] Further, the memory 103 can be used to store the computer program, and the processor 101 implements various functions of the vehicle controller by running or executing the computer program stored in the memory 103 and calling the data stored in the memory 103. The memory 103 may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable memory (PROM), electrically programmable memory (EPROM), electrically erasable programmable memory (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, random access memory is available in a variety of forms, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous random access memory (SDRAM), double data rate synchronous random access memory (DDRSDRAM), enhanced synchronous random access memory (ESDRAM), synchronous link (Synchlink) dynamic random access memory (SLDRAM), memory bus (Rambus) direct random access memory (RDRAM), direct memory bus dynamic random access memory (DRDRAM), and memory bus dynamic random access memory (RDRAM), etc.

[0114] The present invention also provides a readable storage medium, wherein a computer program is stored in the readable storage medium, and when the computer program is executed by a processor, the above-mentioned four-wheel drive vehicle anti-skid control method can be implemented. Since the readable storage medium provided by the present invention and the four-wheel drive vehicle anti-skid control method provided by the present invention belong to the same inventive concept, the readable storage medium provided by the present invention at least has all the beneficial effects of the four-wheel drive vehicle anti-skid control method provided by the present invention. For details, reference can be made to the above description of the beneficial effects of the four-wheel drive vehicle anti-skid control method provided by the present invention, so the beneficial effects of the readable storage medium provided by the present invention will not be described one by one.

[0115] The readable storage medium provided by the present invention can adopt any combination of one or more computer-readable media. The readable medium can be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium can be, for example, but not limited to, a system, device or component of electricity, magnetism, light, electromagnetic, infrared or semiconductor, or any combination of the above. More specific examples (non-exhaustive enumeration) of computer-readable storage media include: an electrical connection with one or more wires, a portable computer hard disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this article, a computer-readable storage medium can be any tangible medium containing or storing a program, which can be used by an instruction execution system, a device or a device or used in combination with it.

[0116] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, which carry computer-readable program codes. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, device, or device. The program code contained on the computer-readable medium may be transmitted using any suitable medium, including but not limited to wireless, wire, optical cable, RF, etc., or any suitable combination of the above.

[0117] In summary, compared with the prior art, the four-wheel drive vehicle anti-skid control method, vehicle controller and readable storage medium provided by the present invention have the following beneficial effects:

[0118] The present invention can reduce the rate of increase of the front axle drive torque and the rear axle drive torque by slowing down the front axle drive torque and the rear axle drive torque in real time according to a preset torque increase slowing algorithm, thereby not only ensuring that the drive torque value can be reduced at the same time, thereby suppressing the occurrence of axle slippage, but also reducing the sensitivity of the driver to adjust the torque through the accelerator pedal, reducing the driver's load, and thus improving the reliability of the vehicle. In summary, the present invention adopts a control strategy of slowing down the front axle drive torque and the rear axle drive torque according to a preset torque increase slowing algorithm in real time to obtain the current front axle slowing rear drive torque and the current rear axle slowing rear drive torque; and controlling the four-wheel drive vehicle according to the current front axle slowing rear drive torque and the current rear axle slowing rear drive torque. This control strategy can actively suppress the continuous slip of the vehicle's two axles when the driver does not actively adjust the driving pedal, so that the control of the four-wheel drive vehicle can be stabilized, ensuring that the four-wheel drive vehicle has good safety and driving performance.

[0119] It should be noted that the computer program code for performing the operation of the present invention can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages-such as Java, Smalltalk, C++, and also conventional procedural programming languages-such as "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as an independent software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer can be connected to the user's computer through any type of network-including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (for example, using an Internet service provider to connect through the Internet).

[0120] It should be noted that the devices and methods disclosed in the embodiments of this article can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to the multiple embodiments of this article. In this regard, each box in the flowchart or block diagram can represent a module, a part of a program or a code, and the module, a part of a program segment or a code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or the flowchart, and the combination of boxes in the block diagram and / or the flowchart, can be implemented by a dedicated hardware-based system for performing a specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions. In addition, the functional modules in the various embodiments of this document may be integrated together to form an independent part, or each module may exist independently, or two or more modules may be integrated to form an independent part.

[0121] It should also be noted that the above description is only a description of the preferred embodiment of the present invention, and is not any limitation on the scope of the present invention. Any changes and modifications made by a person skilled in the art in the field of the present invention based on the above disclosure are within the scope of protection of the present invention. Obviously, a person skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations fall within the scope of the present invention and its equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A four-wheel drive vehicle anti-skid control method, characterized in that: include: Obtaining the driver's required torque; Determining a front axle drive torque allocated to a front drive shaft and a rear axle drive torque allocated to a rear drive shaft according to the driver's required torque and a preset torque distribution strategy; The front axle distributed driving torque and the rear axle distributed driving torque are slowed down in real time according to a preset torque increase slowdown algorithm to obtain a current front axle slowdown rear driving torque and a current rear axle slowdown rear driving torque, and the four-wheel drive vehicle is controlled according to the current front axle slowdown rear driving torque and the current rear axle slowdown rear driving torque.

2. The four-wheel drive vehicle anti-skid control method according to claim 1, characterized in that: The preset torque distribution strategy is to transfer the driving torque of the one with a larger rotation speed between the front drive shaft and the rear drive shaft to the one with a smaller rotation speed.

3. The four-wheel drive vehicle anti-skid control method according to claim 1, characterized in that: The front axle allocated driving torque is slowed down in real time according to a preset torque increase slowdown algorithm to obtain the current front axle slowdown rear driving torque, including: Determine whether the preset front axle mitigation parameter correction trigger condition is currently met; If satisfied, the front axle mitigation parameter is corrected according to the current slip parameter of the front drive axle to obtain the current front axle corrected mitigation parameter; Performing a slowing process on the front axle distributed driving torque according to the current front axle modified slowing parameter to obtain the current front axle slowed driving torque; The step of performing a slowing process on the rear axle allocated driving torque according to a preset slowing torque increase algorithm in real time to obtain the rear axle slowing rear driving torque includes: Determine whether the preset rear axle deceleration parameter correction trigger condition is currently met; If satisfied, the rear axle mitigation parameter is corrected according to the current slip parameter of the rear drive axle to obtain the current rear axle corrected mitigation parameter; The rear axle allocated driving torque is slowed down according to the current rear axle modified slowing down parameter to obtain the current rear axle slowed down rear driving torque.

4. The four-wheel drive vehicle anti-skid control method according to claim 3, characterized in that: The slip parameter is the slip rate.

5. The four-wheel drive vehicle anti-skid control method according to claim 4, characterized in that: The preset front axle mitigation parameter correction trigger condition is that the current slip rate of the front drive shaft is greater than a first preset slip rate threshold and the duration of the slip rate of the front drive shaft being greater than the first preset slip rate threshold is equal to a first preset duration; The preset rear axle deceleration parameter correction trigger condition is that the current slip rate of the rear drive shaft is greater than a second preset slip rate threshold and the duration for which the slip rate of the rear drive shaft is greater than the second preset slip rate threshold is equal to a second preset duration.

6. The four-wheel drive vehicle anti-skid control method according to claim 4, characterized in that: The method of correcting the front axle mitigation parameter according to the current slip parameter of the front drive axle to obtain the current front axle corrected mitigation parameter includes: determining a current front axle correction coefficient according to a current slip rate of the front drive axle; Correcting the front axle mitigation parameter according to the current front axle correction coefficient to obtain a current front axle correction mitigation parameter; The step of correcting the rear axle mitigation parameter according to the current slip parameter of the rear drive axle to obtain the current rear axle corrected mitigation parameter includes: determining a current rear axle correction coefficient according to a current slip rate of the rear drive axle; The rear axle mitigation parameter is corrected according to the current rear axle correction coefficient to obtain a current rear axle correction mitigation parameter.

7. The anti-skid control method for a four-wheel drive vehicle according to claim 6, characterized in that: Determining the current front axle correction coefficient according to the current slip rate of the front drive shaft includes: Determining a current front axle correction coefficient according to a current slip rate of the front drive axle, a first intensity factor, a first vehicle speed factor, and a first accelerator pedal change rate factor, wherein a product of the first intensity factor, the first vehicle speed factor, and the first accelerator pedal change rate factor is less than or equal to 1; Determining the current rear axle correction coefficient according to the current slip rate of the rear drive axle includes: The current rear axle correction coefficient is determined based on the current slip rate of the rear drive shaft, the second intensity factor, the second vehicle speed factor and the second accelerator pedal change rate factor, wherein the product of the second intensity factor, the second vehicle speed factor and the second accelerator pedal change rate factor is less than or equal to 1.

8. The anti-skid control method for a four-wheel drive vehicle according to claim 3, characterized in that: The mitigation parameters include filtering parameters and gradient limiting parameters.

9. A vehicle controller, characterized in that: The invention comprises a processor and a memory, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the anti-skid control method for driving of a four-wheel drive vehicle according to any one of claims 1 to 8 is implemented.

10. A readable storage medium, characterized in that: The readable storage medium stores a computer program, and when the computer program is executed by a processor, the four-wheel drive vehicle anti-skid control method according to any one of claims 1 to 8 is implemented.

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