A vehicle torque control method, apparatus and device

Abstract

The application relates to the computer technical field, in particular to a vehicle torque control method, device and equipment, the method obtains the corresponding front-rear wheel speed difference through the front-rear wheel speed difference of the target vehicle, and when the target vehicle meets the torque adjustment condition, the front-rear axle torque of the target vehicle is adjusted according to the total demand torque of the target vehicle and the front-rear wheel speed difference, and the target front-rear axle torque is obtained. In this way, by monitoring the front-rear wheel speed difference of the vehicle in real time, when the vehicle may slip or turn unstable, the front-rear axle torque is dynamically adjusted and balanced in time by using feedback control, so that the front-rear axle works cooperatively, the risk of losing control caused by the vehicle slipping or insufficient adhesion is reduced, the smooth driving of the vehicle is ensured, the situation of excessive slipping or insufficient adhesion of the vehicle in different terrains or complex road conditions is effectively avoided, and the control performance and safety stability of the vehicle driving are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of computer, and particularly relates to a vehicle torque control method, device and equipment. BACKGROUND

[0002] With the enhancement of global awareness of sustainable development and environmental protection, electric vehicles (EV) gradually become a new development trend of the automobile industry. With the progress of battery technology and the improvement of the range, the application range of electric vehicles is continuously expanding, and the vehicle models are gradually expanding to off-road vehicles to meet the expectations of consumers for diversified travel needs.

[0003] However, the existing technology of pure electric off-road vehicles still has certain technical defects in the design of the power system, especially in complex off-road terrain. The front and rear axle adhesion of the pure electric off-road vehicle will frequently fluctuate due to terrain changes, resulting in the phenomenon that the rotation speed of the front and rear axles cannot change synchronously, which not only reduces the handling performance of the vehicle, but also causes the energy of the vehicle power system to be unable to be fully utilized, reduces the power transmission efficiency, and greatly reduces the stability and safety of the driving of the pure electric off-road vehicle. SUMMARY

[0004] The present application provides a vehicle torque control method, device and equipment to improve the handling performance and safety stability of the vehicle driving.

[0005] In a first aspect, the present application provides a vehicle torque control method, which comprises:

[0006] obtaining a corresponding front and rear wheel speed difference based on the front and rear axle wheel speed of the target vehicle, wherein the front and rear axle wheel speed represents the front axle wheel speed and the rear axle wheel speed of the corresponding vehicle;

[0007] judging whether the target vehicle meets a preset torque adjustment condition based on the front and rear wheel speed difference and the vehicle driving state;

[0008] adjusting the front and rear axle torque of the target vehicle based on the total demand torque of the target vehicle and the front and rear wheel speed difference to obtain the target front and rear axle torque when the target vehicle meets the torque adjustment condition.

[0009] In a second aspect, the present application provides a vehicle torque control device, which comprises:

[0010] an acquisition unit, configured to obtain a corresponding front and rear wheel speed difference based on the front and rear axle wheel speed of the target vehicle, wherein the front and rear axle wheel speed represents the front axle wheel speed and the rear axle wheel speed of the corresponding vehicle;

[0011] determining whether the target vehicle satisfies a preset torque adjustment condition based on the front-rear wheel speed difference and a vehicle driving state;

[0012] adjusting front-rear axle torques of the target vehicle based on a total demand torque of the target vehicle and the front-rear wheel speed difference to obtain target front-rear axle torques when the target vehicle satisfies the torque adjustment condition.

[0013] Optionally, the torque adjustment condition comprises that the front-rear wheel speed difference is greater than a wheel speed difference threshold and the vehicle driving state is a driving state.

[0014] Optionally, the adjusting unit is specifically configured to:

[0015] obtain a current torque ratio of the target vehicle when the front-rear wheel speed difference is greater than the wheel speed difference threshold; the current torque ratio represents a ratio between a current front axle torque and a current rear axle torque of the corresponding vehicle;

[0016] perform proportional adjustment on the current torque ratio based on a preset proportional distribution strategy until the target vehicle satisfies an adjustment termination condition to obtain a target torque ratio; the adjustment termination condition represents that the front-rear wheel speed difference is less than the wheel speed difference threshold;

[0017] obtain target front-rear axle torques based on the target torque ratio and the total demand torque.

[0018] Optionally, the adjusting unit is further configured to:

[0019] obtain a vehicle adhesion coefficient based on a wheel driving state of the target vehicle; the vehicle adhesion coefficient represents a grip force between the corresponding vehicle and the ground; the wheel driving state comprises driving forces and slip states of each wheel of the corresponding vehicle;

[0020] obtain target wheel speeds of the each wheel based on an actual speed of the target vehicle;

[0021] obtain a target total demand torque by adjusting the total demand torque based on the front-rear axle speeds, the target wheel speeds and the vehicle adhesion coefficient when the front-rear axles of the target vehicle are in the slip state.

[0022] Optionally, the adjusting unit is specifically configured to:

[0023] obtain a difference value between the wheel speed average value and the target wheel speed based on the wheel speed average value of the front-rear axle speeds;

[0024] obtain a total torque threshold corresponding to the total demand torque based on the vehicle adhesion coefficient;

[0025] Based on the difference value and the total torque threshold, the total demand torque is reduced to obtain the target total demand torque, and the target total demand torque is greater than the total torque threshold.

[0026] Optionally, the adjusting unit is specifically used for:

[0027] The driving force and the normal pressure corresponding to each wheel are obtained, and the normal pressure represents the pressure between the corresponding wheel and the ground in the vertical direction.

[0028] For each wheel, when it is determined that the wheel is in a non-slip state, the wheel adhesion coefficient corresponding to each wheel is obtained based on the driving force and the normal pressure of each wheel, and the wheel adhesion coefficient represents the grip between the corresponding wheel and the ground.

[0029] Based on the relative size relationship between the wheel adhesion coefficients, the maximum wheel adhesion coefficient is taken as the vehicle adhesion coefficient.

[0030] Optionally, the adjusting unit is further used for:

[0031] Based on the current single-axis wheel speed and the target single-axis wheel speed of each axle, a target axle to be adjusted is determined, the current single-axis wheel speed represents the current left and right wheel speed of the corresponding axle, and the target single-axis wheel speed is determined based on the actual vehicle speed of the target vehicle.

[0032] Based on the single-axis adhesion coefficient of the target axle, the single-axis demand torque of the target axle is iteratively adjusted until the difference between the current single-axis wheel speed of the target axle and the target single-axis wheel speed is less than a preset difference threshold, and the single-axis adhesion coefficient represents the grip between the corresponding axle and the ground.

[0033] Optionally, each iteration adjustment process includes:

[0034] Based on the difference between the current single-axis wheel speed and the target single-axis wheel speed, a single-axis adjustment difference value corresponding to the target axle is obtained.

[0035] Based on the single-axis adhesion coefficient, a single-axis torque threshold of the target axle is obtained.

[0036] Based on the single-axis adjustment difference value and the single-axis torque threshold, the single-axis demand torque is reduced to obtain the target single-axis demand torque, and the target single-axis demand torque is greater than the single-axis torque threshold.

[0037] In a third aspect, a computer device is provided, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements any one of the vehicle torque control methods in the first aspect when executing the computer program.

[0038] In a fourth aspect, a computer storage medium is provided, and the computer storage medium stores computer program instructions, and the computer program instructions are executed by a processor to implement any one of the vehicle torque control methods in the first aspect.

[0039] In a fifth aspect, a computer program product is provided, and the computer program product includes computer program instructions, and the computer program instructions are executed by a processor to implement any one of the vehicle torque control methods in the first aspect.

[0040] The present application has the following advantages:

[0041] The embodiments of the present application provide a vehicle torque control method, the front and rear wheel speed difference of a target vehicle is obtained, and when the target vehicle meets a torque adjustment condition, the front and rear axle torques of the target vehicle are adjusted according to the total demand torque of the target vehicle and the front and rear wheel speed difference, and the target front and rear axle torques are obtained. In this way, by monitoring the front and rear wheel speed difference of the vehicle in real time, when the vehicle may have problems such as slipping or unstable steering, the front and rear axle torques are dynamically adjusted and balanced in time by using feedback control, so as to cooperate with the front and rear axle work, reduce the risk of losing control of the vehicle due to slipping or insufficient adhesion, ensure the smooth driving of the vehicle, effectively avoid the situation that the vehicle slips excessively or has insufficient adhesion in different terrains or complex road conditions, and improve the control performance and safety and stability of the vehicle driving. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related art, the drawings needed to be used in the embodiments or the related art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0043] Figure 1 A structural schematic diagram of a traditional mechanical four-wheel drive vehicle is provided for the embodiments of the present application;

[0044] Figure 2 A structural schematic diagram of an electric four-wheel drive vehicle is provided for the embodiments of the present application;

[0045] Figure 3 A system block diagram of a vehicle torque control system is provided for the embodiments of the present application;

[0046] Figure 4 A flowchart of a vehicle torque control method is provided for the embodiments of the present application;

[0047] Figure 5A process diagram of front and rear axle torque adjustment provided for an embodiment of the present application is shown in FIG. 1.

[0048] Figure 6 A flow diagram of another vehicle torque control method provided for an embodiment of the present application is shown in FIG. 2.

[0049] Figure 7 A process diagram of total demand torque adjustment provided for an embodiment of the present application is shown in FIG. 3.

[0050] Figure 8 A flow diagram of another vehicle torque control method provided for an embodiment of the present application is shown in FIG. 4.

[0051] Figure 9 A process diagram of single axle torque adjustment provided for an embodiment of the present application is shown in FIG. 5.

[0052] Figure 10 An effect diagram of front and rear axle torque equalization control under the related art provided for an embodiment of the present application is shown in FIG. 6.

[0053] Figure 11 An effect diagram of vehicle torque control provided for an embodiment of the present application is shown in FIG. 7.

[0054] Figure 12 A structure diagram of a vehicle torque control device provided for an embodiment of the present application is shown in FIG. 8.

[0055] Figure 13 A structure diagram of a computer device provided for an embodiment of the present application is shown in FIG. 9. DETAILED DESCRIPTION

[0056] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application. In the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other at will. And, although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that here.

[0057] The terms "first" and "second" in the specification and claims of the present application and the above drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the term "comprising" and any variations thereof are intended to cover non-exclusive protection. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to the process, method, product or device. "Multiple" in the present application can mean at least two, for example, can be two, three or more, and the embodiments of the present application are not limited.

[0058] The term "and / or" in the embodiments of the present application is only used to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects have an "or" relationship.

[0059] It can be understood that in the following specific embodiments of the present application, data related to vehicle operation data and the like are involved, and when the embodiments of the present application are applied to specific products or technologies, relevant permissions or consents are required, and the collection, use and processing of relevant data need to comply with relevant laws, regulations and standards of relevant countries and regions. For example, relevant volunteers can be recruited and sign a relevant agreement of volunteer authorized data, and then the data of these volunteers can be used for implementation; or by implementing within the scope of an organization that has been authorized to allow, by using the data of internal members of the organization to implement the following embodiments for data management; or the relevant data used in the specific implementation are all simulation data, for example, simulation data generated in a virtual scene.

[0060] The design idea of the embodiments of the present application is briefly introduced as follows.

[0061] With the increasing awareness of sustainable development and environmental protection around the world, pure electric vehicles have gradually become a new development trend of the automobile industry, and with the progress of battery technology and the improvement of endurance mileage, the application range of pure electric vehicles is continuously expanding, and the vehicle type is gradually expanding to off-road vehicles, meeting the expectations of consumers for diversified travel needs.

[0062] As Figure 1The structure diagram of a traditional mechanical four-wheel drive vehicle is shown, which includes an engine, an angle transmission device, a transmission shaft, an all-wheel drive clutch, a front / rear axle drive, a front / rear axle differential, and a gearbox. The engine is used to provide a power source for the vehicle. The traditional mechanical four-wheel drive vehicle usually uses an internal combustion engine to transmit power to the transmission system. The angle transmission device is used to transmit power from the engine at different angles into the transmission shaft, adapting to the power transmission requirements between the front and rear wheels. The transmission shaft connects the front and rear axles, transmitting power from the front to the rear, and is a key component in the mechanical four-wheel drive system, ensuring that engine power can act on the front and rear wheels simultaneously. The all-wheel drive clutch is responsible for engaging or disconnecting the power transmission of the rear axle when four-wheel drive is needed, so that the vehicle can switch between two-wheel drive and four-wheel drive modes. The gearbox is used to transmit power from the engine at different angles into the transmission shaft, adapting to the power transmission requirements between the front and rear wheels. The differential adjusts the speed difference of the wheels, achieving flexible drive force distribution. However, in order to achieve more flexible front and rear axle torque distribution, the current pure electric off-road vehicle model cancels the central differential and differential lock of the traditional mechanical four-wheel drive vehicle, and configures front and rear dual motors, combined with electronic control of front and rear axle torque distribution. As shown in Figure 2 The structure diagram of an electric four-wheel drive vehicle is shown, which includes a vehicle controller, a drive unit, a transmission device, and a differential. The vehicle controller is used to control the front and rear axle drive torque distribution instructions, as well as the distribution and management of energy. Drive unit A and drive unit B correspond to the front and rear axle motor drive units respectively, driving the wheels on the front and rear axles through electric power, and are connected to the transmission system on the front and rear axles respectively. The transmission device and the differential transmit power from the drive unit to the wheels, adjusting the speed difference of the wheels to achieve flexible drive force distribution. Although this change can achieve more flexible front and rear axle torque distribution compared to the traditional mechanical four-wheel drive, the related technical pure electric off-road vehicle still has certain technical defects in the design of the power system, especially in complex off-road terrain. The front and rear axle adhesion of the pure electric off-road vehicle will fluctuate frequently due to terrain changes, resulting in different front and rear axle slip rates, which not only reduces the driving controllability of the vehicle, but also causes the energy of the vehicle power system to be underutilized, reducing power transmission efficiency, thereby greatly reducing the stability and safety of the pure electric off-road vehicle driving.

[0063] In view of the above problems, the embodiment of the present application provides a vehicle torque control method, the front and rear wheel speed difference of the target vehicle is obtained, and when the target vehicle meets the torque adjustment condition, the front and rear axle torque of the target vehicle is adjusted according to the total demand torque of the target vehicle and the front and rear wheel speed difference, and the target front and rear axle torque is obtained. In this way, by monitoring the front and rear wheel speed difference of the vehicle in real time, when the vehicle may slip or turn unstable, the front and rear axle torque is dynamically adjusted and balanced in time by using feedback control, so as to cooperate with the front and rear axle, reduce the risk of losing control caused by slipping or insufficient adhesion of the vehicle, and ensure the smooth driving of the vehicle, effectively avoid the situation of excessive slipping or insufficient adhesion of the vehicle in different terrains or complex road conditions, and improve the operation performance and safety and stability of the vehicle driving.

[0064] The application scenarios to which the technical solutions of the embodiments of the present application can be applied will be briefly introduced below. It should be noted that the application scenarios introduced below are only used to illustrate the embodiments of the present application and are not limited. In the specific implementation process, the technical solutions provided by the embodiments of the present application can be flexibly applied according to actual needs.

[0065] The scheme provided by the embodiments of the present application can be applied to most driving scenarios of four-wheel drive vehicles, for example, vehicle models with power output on both front and rear axles and without a central differential, including double-motor, three-motor, four-motor configurations, and also including pure electric vehicle models and hybrid vehicle models with parallel mode, for improving the vehicle handling, stability and safety. For example, electric vehicles on complex terrains such as mountains, deserts and mud, the vehicle faces different road adhesion, and is prone to slipping or losing control. As shown in the figure, the front and rear wheel speed difference of the vehicle is monitored in real time, and when the vehicle meets the torque adjustment condition, the front and rear axle torque of the vehicle is adjusted according to the total demand torque of the vehicle and the front and rear wheel speed difference, and the target front and rear axle torque is obtained. In this way, by monitoring the front and rear wheel speed difference of the vehicle in real time, when the vehicle may slip or turn unstable, the front and rear axle torque is dynamically adjusted and balanced in time by using feedback control, so as to cooperate with the front and rear axle, reduce the risk of losing control caused by slipping or insufficient adhesion of the vehicle, and ensure the smooth driving of the vehicle, effectively avoid the situation of excessive slipping or insufficient adhesion of the vehicle in different terrains or complex road conditions, and improve the operation performance and safety and stability of the vehicle driving. Figure 3 The system block diagram of a vehicle torque control system provided by the embodiments of the present application is shown in the figure. The vehicle controller of the electric vehicle can obtain the wheel speed, 6-axis inertial navigation, accelerator pedal opening, brake pedal opening, gear and other parameters of the vehicle in real time through sensors, accelerator / brake pedals, gears, axles and other devices, and output the corresponding motor torque instruction based on the vehicle torque control method provided by the embodiments of the present application, so as to adjust the front and rear axle torque, total demand torque and single axle demand torque, realize the front and rear axle speed synchronization, and control the slip rate of the vehicle wheel, so that the capability of the vehicle power system is fully utilized, the power torque of the off-road vehicle is accurately distributed, and the vehicle can obtain appropriate driving force and adhesion on different terrains to avoid vehicle deviation or sinking, and improve the operation performance and safety and stability of the vehicle driving.

[0066] Of course, the method provided by the embodiments of the present application is not limited to the above application scenarios, and can also be used in other possible application scenarios, which are not limited by the embodiments of the present application. The functions that can be achieved by each device in the above application scenarios will be described in the subsequent method embodiments, and will not be described here in more detail.

[0067] The following describes the methods provided by exemplary embodiments of this application in conjunction with the application scenarios described above and with reference to the accompanying drawings. It should be noted that the application scenarios described above are only shown to facilitate understanding of the spirit and principles of this application, and the embodiments of this application are not limited in any way in this respect.

[0068] See Figure 4 The diagram shown is a flowchart of a vehicle torque control method provided in an embodiment of this application. The specific implementation flow of this method is as follows:

[0069] Step 401: Based on the front and rear axle wheel speeds of the target vehicle, obtain the corresponding front and rear wheel speed difference.

[0070] In this embodiment, the target vehicle represents the object that needs to be torque controlled, and the front and rear axle wheel speeds represent the front axle wheel speed and the rear axle wheel speed of the vehicle. Thus, the front and rear wheel speed difference of the target vehicle can be obtained based on the difference between the front axle wheel speed and the rear axle wheel speed.

[0071] Specifically, in this embodiment of the application, the real-time wheel speed of the target vehicle, i.e., the front axle wheel rotation speed w, can be obtained in real time through a wheel speed sensor. f and rear axle wheel speed w r And according to w f and w r The difference between them is used to calculate the current front and rear wheel speed difference Δw=|w r -w f |

[0072] Step 402: Based on the front and rear wheel speed difference and the vehicle's driving status, determine whether the target vehicle meets the preset torque adjustment conditions.

[0073] In this embodiment, the front and rear wheel speed difference reflects the vehicle's slippage state. That is, when the speed of one axle's wheels is significantly higher than that of the other axle, it may indicate that the vehicle is slipping, and the current front and rear axle torque is not suitable for the road conditions. The vehicle's driving state reflects its current driving conditions; the vehicle's torque requirements for the front and rear axles differ depending on whether it is in a driving or stationary state. Therefore, by acquiring the target vehicle's current front and rear wheel speed difference and driving state in real time, it is possible to comprehensively determine whether the vehicle meets the torque adjustment conditions, thereby deciding whether to enable control of the target vehicle, i.e., to perform subsequent torque adjustment processing.

[0074] In one possible implementation, the torque adjustment condition in this application embodiment may be: the front and rear wheel speed difference of the target vehicle is greater than a preset wheel speed difference threshold, and the vehicle is in a driving state.

[0075] Specifically, when the front and rear wheel speed difference is greater than the wheel speed difference threshold, i.e., the wheel speed of a certain axle is obviously faster than that of another axle, it may represent that a certain axle of the target vehicle has slipped or lost grip, and the current torque distribution is not suitable for the road condition. Moreover, if the vehicle driving state of the target vehicle is a driving state at this time, i.e., the vehicle is in a power output working state, and the driving system (motor or engine) is exerting torque on the wheels, the front and rear axles of the vehicle still need different driving force distribution to maintain the vehicle operation. Therefore, when it is determined that the vehicle meets the torque adjustment condition, the vehicle controller will trigger the subsequent torque adjustment process to redistribute the torque proportion of the front and rear axles to reduce the wheel speed difference and maintain the stability of the vehicle driving. Without meeting the above conditions, the torque adjustment can also be unnecessary to avoid unnecessary power waste.

[0076] In a possible implementation, whether the vehicle is in a driving state can be determined according to the accelerator pedal and the brake pedal. For example, the vehicle controller can obtain the driving demand of the driver for acceleration or deceleration in real time through the opening degree sensors of the accelerator pedal and the brake pedal to determine the current driving state of the target vehicle.

[0077] Specifically, when the accelerator pedal opening degree is greater than 0% and the brake pedal opening degree is equal to 0%, i.e., the accelerator pedal has an opening degree and the brake pedal has no opening degree, it indicates that the driver wants to accelerate the vehicle, and the vehicle is in a driving state. When the accelerator pedal opening degree is equal to 0% and the brake pedal opening degree is greater than 0%, i.e., the accelerator pedal has no opening degree and the brake pedal has an opening degree, it indicates that the driver wants to decelerate or brake the vehicle, and at this time, the vehicle is in a non-driving state because the brake system is working and the power system is not outputting torque. When the accelerator pedal opening degree is equal to 0% and the brake pedal opening degree is equal to 0%, i.e., when the accelerator and brake pedals have no opening degree, it indicates that the driver does not request acceleration or deceleration, and the vehicle can be in a non-driving state such as a coasting state or a stationary state.

[0078] Step 403: When the target vehicle meets the torque adjustment condition, the front and rear axle torques of the target vehicle are adjusted based on the total demand torque and the front and rear wheel speed difference of the target vehicle to obtain target front and rear axle torques.

[0079] In the embodiments of the present application, the total demand torque represents the total driving force demand of the target vehicle, and determines how much the total driving force of the vehicle is converted into the torque values of the front and rear axles. Therefore, in the embodiments of the present application, when it is determined that the target vehicle meets the torque adjustment condition, the total demand torque and the front and rear wheel speed difference are combined to adjust the front and rear axle torques through the vehicle controller to obtain the target front and rear torques that meet the actual driving demand, so as to simulate the front and rear axle torque characteristics when the central clutch of the mechanical four-wheel drive vehicle is locked or partially locked, make the front and rear axles of the target vehicle drive in a fixed torque proportion linkage, avoid the front and rear wheels from generating a too large front and rear wheel speed difference due to different road conditions, and disperse the driving force, so that the front and rear axle torques of the target vehicle realize synchronous characteristic change.

[0080] In a possible implementation, the specific adjustment process of the front and rear axle torques of the target vehicle according to the embodiments of the present application can be as follows: when the front and rear wheel speed difference of the target vehicle is greater than a preset wheel speed difference threshold, the current torque ratio of the target vehicle, that is, the ratio between the current front axle torque and the current rear axle torque of the target vehicle, is obtained. According to a preset proportion distribution strategy, the current torque ratio is proportionally adjusted until the target vehicle satisfies the adjustment termination condition, and the current torque ratio obtained at this time is taken as the target torque ratio, so that the front axle torque and the rear axle torque are redistributed according to the obtained target torque ratio and the total required torque to obtain the target front and rear axle torques.

[0081] In a possible implementation, the embodiments of the present application can determine that the target vehicle satisfies the adjustment termination condition when the current front and rear wheel speed difference of the target vehicle is less than the wheel speed difference threshold, stop the proportional adjustment of the current torque ratio, and output the target torque ratio obtained at this time. In order to improve the accuracy of torque adjustment, the embodiments of the present application can also stop the torque ratio adjustment when it is determined that the current front and rear wheel speed difference of the target vehicle is less than the wheel speed difference threshold and this less-than condition lasts for a certain length of time.

[0082] Specifically, the embodiments of the present application can proportionally adjust the current torque ratio by setting a feedback adjustment step size. Taking the total required torque of the target vehicle as T total , the current front and rear axle torque ratio as a f and a r =1-a f , for example, when it is determined that the target vehicle satisfies the torque adjustment condition, that is, the front and rear wheel speed difference Δw is greater than the wheel speed difference threshold Δw th , the torque distribution will be continuously adjusted through wheel speed difference feedback control. The feedback adjustment step size is set as Δa, and when a f >a r and Δw>Δw th , the torque ratio of the rear axle will be increased and the torque ratio of the front axle will be decreased according to the feedback adjustment step size, that is, the torque adjustment a f =a f -Δa, a r =1-a f each time. Similarly, when a f is less than a r and Δw>Δw th , the torque ratio of the rear axle will be decreased and the torque ratio of the front axle will be increased according to the feedback adjustment step size, that is, the torque adjustment a f =a f +Δa, a r =1-a f each time. In this way, until the current front and rear wheel speed difference of the target vehicle is less than the wheel speed difference threshold (Δw<Δwth ), and for a certain period of time (for example, more than 2 seconds), the feedback control will stop, and the target torque ratio obtained at this time will be output and maintained. According to the latest target torque ratio, the actual torques of the front and rear axles are updated in real time, that is, the actual torque of the front axle T f = a f · T total , and the actual torque of the rear axle T r = a r · T total , so that the torques between the front and rear axles of the vehicle reach a balanced state.

[0083] In one possible implementation, please refer to Figure 5 Fig. 1 shows a process diagram of front and rear axle torque adjustment provided by an embodiment of the present application. In the front and rear axle torque adjustment process, the wheel speeds of the front and rear axles of the vehicle will be used for wheel speed difference feedback control. The wheel speed difference, the total required torque, and the current front and rear axle torque distribution ratio are obtained by the vehicle controller, so as to realize electronic differential lock control enabling judgment by using the front and rear axle torque adjustment strategy provided by the embodiment of the present application, and output the updated torque distribution ratio.

[0084] Specifically, taking the example of an electric four-wheel drive vehicle driving on a muddy road section, the front axle wheel speed and the rear axle wheel speed of the vehicle are continuously monitored by a wheel speed sensor, and the vehicle controller obtains relevant data of front and rear axle torque adjustment through vehicle devices such as the wheel speed sensor. When the front wheels of the vehicle sink into a mud pit and start to slip, the wheel speed of the front axle will rapidly increase, while the wheel speed of the rear axle is relatively small. When the vehicle controller detects that the wheel speed difference between the front and rear axles is greater than a preset wheel speed difference threshold (for example, the wheel speed of the front axle is twice the wheel speed of the rear axle), it represents that the front axle is idling and the rear axle lacks sufficient torque. The vehicle controller will start the enable control to adjust the front and rear axle torque, that is, according to the wheel speed difference feedback control, continuously adjust the torque distribution. At this time, the front axle does not need too much torque because of slipping, while the rear axle has better grip and needs to increase torque. The vehicle controller will combine the current total demand torque of the vehicle to reduce the power distributed to the front axle and increase the power of the rear axle. For example, the vehicle currently needs a total torque of 200 Nm. Due to the slipping of the front wheels, 60% of the torque can be distributed to the rear wheels, and 40% to the front wheels, or in an extreme case, even most of the torque (such as 90%) is distributed to the rear wheels. Adjusting the distribution ratio of the front and rear axle torque, the torque is redistributed to the front and rear axles to ensure that the rear wheels can push the vehicle out of the trouble and successfully drive the vehicle out of the mud pit. During the entire torque adjustment process, the vehicle controller updates the current front and rear axle torque distribution ratio in real time and continuously adjusts the torque according to the latest changes in road conditions. With the redistribution of the front and rear axle torque, the wheel speed difference of the front wheels gradually decreases, and the rear wheels obtain more power until the current wheel speed difference between the front and rear wheels of the target vehicle is less than the wheel speed difference threshold and lasts for a certain period of time, which represents that the vehicle returns to normal driving. The torque adjustment can be stopped. In this way, through the above-mentioned front and rear axle torque adjustment method, the embodiments of the present application make the front and rear axle torque of the vehicle achieve the desired synchronous characteristic change.

[0085] In order to further improve the stability of vehicle driving, in addition to the above-mentioned front and rear axle torque adjustment, the embodiments of the present application can also adjust the total demand torque of the target vehicle, so as to ensure the adaptability of power output to the driving environment and further avoid the problem of slipping caused by excessive torque.

[0086] Referring to Figure 6 Fig. 6 shows a flowchart of another vehicle torque control method provided by the embodiments of the present application. The method is used to adjust the total demand torque of the target vehicle. The specific implementation process of the flowchart is as follows:

[0087] Step 601: Obtain the vehicle adhesion coefficient based on the wheel driving state of the target vehicle.

[0088] In the embodiments of the present application, the wheel driving state includes driving force and slip state of each wheel of the target vehicle. For example, taking an electric four-wheel drive vehicle as an example, the vehicle has two front axle wheels and two rear axle wheels. The vehicle adhesion coefficient represents the size of the grip between the target vehicle and the ground, that is, the friction characteristic between the vehicle tire and the road surface.

[0089] In a possible implementation, the vehicle adhesion coefficient can be defined as the ratio of the adhesion force to the normal (i.e., perpendicular to the road surface) pressure of the wheel. Therefore, in order to update the adhesion coefficient of the target vehicle in real time, the embodiments of the present application can accurately determine the maximum adhesion capacity between the vehicle and the road surface by monitoring the wheel driving force and the slip state in real time, and dynamically adjust the adhesion coefficient according to the adhesion state to ensure the stability and maneuverability of the vehicle. The specific process is as follows: The embodiments of the present application obtain the driving force of each wheel and the pressure of each wheel on the ground in the vertical direction, that is, the normal pressure of the wheel. For each wheel, when it is determined that the wheel is in a non-slip state, the wheel adhesion coefficient of each wheel is obtained according to the driving force and the normal pressure of the wheel. The wheel adhesion coefficient represents the size of the grip between the corresponding wheel and the ground. Therefore, according to the relative size relationship between the wheel adhesion coefficients of each wheel, the maximum wheel adhesion coefficient is taken as the vehicle adhesion coefficient of the target vehicle.

[0090] Specifically, the slip state of the wheel is the core factor for dynamic updating of the adhesion coefficient. The embodiments of the present application can determine whether the vehicle is slipping by the difference between the actual wheel speed and the actual vehicle speed of the wheel, or whether the wheel acceleration is greater than a limit value. It is worth mentioning that the embodiments of the present application can select other ways to determine the slip state according to actual needs, which are not limited herein. When it is determined that the wheel is not slipping, the wheel adhesion coefficient of each wheel can be calculated separately according to the driving force of the wheel and the normal pressure of the wheel. The specific calculation formula is as follows:

[0091]

[0092] Wherein, u i represents the wheel adhesion coefficient of the i-th wheel. Taking an electric four-wheel drive vehicle as an example, the four wheels can include a front left wheel, a front right wheel, a rear left wheel and a rear right wheel,

[0093] F Ni represents the normal pressure of the i-th wheel, reflecting the maximum grip that the wheel can provide. In the case of static or uniform speed driving, the normal pressure can be calculated by the gravity of the vehicle and the weight distributed to each wheel

[0094] F TiThe driving force of the i-th wheel, i.e. the pushing force output by the engine or motor during vehicle driving and finally applied to each wheel. The driving force value of each wheel can be obtained by real-time monitoring of the driving force sensor data.

[0095] In summary, after calculating the wheel adhesion coefficients of each wheel separately, the wheel adhesion coefficients of all wheels are compared to select the maximum wheel adhesion coefficient as the vehicle adhesion coefficient. In the case of non-slip, the vehicle adhesion coefficient needs to be adjusted in real time with the changes of dynamic factors such as road conditions, vehicle speed, load, etc. Therefore, after calculating a new maximum wheel adhesion coefficient each time, the vehicle adhesion coefficient needs to be updated. In order to avoid the over-frequent adjustment of the vehicle adhesion coefficient due to temporary changes in the road surface and ensure the stability of the vehicle, the embodiments of the present application also judge whether the newly calculated maximum wheel adhesion coefficient has changed significantly when updating the vehicle adhesion coefficient.

[0096] Step 602: Obtain the target wheel speed of each wheel based on the actual vehicle speed of the target vehicle.

[0097] In the embodiments of the present application, the target wheel speed represents the ideal rotational speed that the wheel should reach under the current vehicle speed and road conditions. By comparing the target wheel speed with the actual wheel speed, the deviation of the actual wheel speed from the ideal state can be identified, and then it can be judged whether there is a slip or idling phenomenon. If there is a significant difference between the actual wheel speed and the target wheel speed, it may indicate that the adhesion between the wheel and the ground is insufficient, resulting in slip, thereby providing a basis for subsequent total demand torque adjustment.

[0098] Specifically, the embodiments of the present application can calculate the wheel angular velocity of each wheel by substituting the known wheel driving slip ratio, wheel dynamic turning radius and actual vehicle speed into the calculation formula of the wheel driving slip ratio. Then, the target wheel speed of each wheel is obtained by converting the wheel angular velocity of each wheel through the wheel speed calculation formula. The specific formula is as follows:

[0099]

[0100] wherein λ d represents the wheel driving slip ratio, i.e. the relative sliding degree between the driving wheel and the ground, which is used to measure the degree of wheel slip. For example, when λ d = 0, it represents that there is no relative sliding between the wheel and the ground, and the wheel completely relies on the ground adhesion to move forward; when λ d increases, it indicates that the wheel sliding or slipping is more serious

[0101] ω is the wheel angular velocity, i.e., the rotation speed of the wheel, which can be in rad / s, indicating the number of radians per second that the wheel rotates, reflecting the rotation of the wheel. The higher the angular velocity, the faster the wheel rotates.

[0102] γ is the dynamic wheel radius, representing the effective radius of the wheel under the loaded state, i.e., the actual radius of the wheel under the moving state after the wheel contacts the ground. This radius is affected by factors such as load and vehicle speed.

[0103] v is the reference vehicle speed, i.e., the actual vehicle speed of the vehicle, which can be measured by a speed sensor, representing the linear speed of the vehicle as a whole.

[0104] n represents the target wheel speed of the wheel.

[0105] Step 603: When the front and rear axles of the target vehicle are in a slipping state, the total demand torque is adjusted based on the front and rear axle speeds, the target wheel speed of each wheel, and the vehicle adhesion coefficient, to obtain a target total demand torque.

[0106] In the embodiments of the present application, when the front and rear axles of the target vehicle are in a slipping state, it means that the adhesion between the front and rear axle wheels and the ground is not sufficient to support the current demand of the vehicle. The slipping state also reflects that the driving force of the vehicle exceeds the friction (adhesion) limit between the wheel and the ground, resulting in that the tire cannot effectively grip the ground, and the wheel may be in a fast rotation but the vehicle cannot accelerate correspondingly, i.e., an "idling" state. Therefore, the embodiments of the present application need to adjust and control the total demand torque based on the front and rear axle speeds, the target wheel speed of each wheel, and the vehicle adhesion coefficient, to gradually reduce the total demand torque, so that the target total demand torque does not exceed the range that the adhesion can withstand, so that the vehicle can better maintain a stable driving state and improve the handling of the vehicle.

[0107] Specifically, the embodiments of the present application can determine whether the front and rear axles are slipping by the difference between the actual wheel speed of the axle and the actual vehicle speed of the vehicle, or whether the wheel acceleration is greater than a limit value. Of course, other ways of determining the slipping state can also be selected according to actual needs, which are not limited in the embodiments of the present application.

[0108] In one possible implementation, the embodiments of the present application obtain the difference between the average wheel speed and the target wheel speed according to the average wheel speed of the front and rear axles. And the total torque threshold corresponding to the total demand torque is obtained according to the vehicle adhesion coefficient. Thus, the total demand torque is reduced by combining the difference and the total torque threshold to obtain the target total demand torque, and the target total demand torque is ensured to be greater than the total torque threshold.

[0109] Specifically, the embodiment of the present application can use a proportion integration differentiation (PID) control method to dynamically and accurately adjust the total demand torque, so as to realize smooth and reliable vehicle driving. First, a difference between the average value of the front and rear wheel speeds and the target wheel speed is calculated, and the difference is taken as the input of the PID control, that is, the slip error, to reflect the slip state of the current wheel. Through the PID formula combined with the slip error, the adjustment amount of each total demand torque adjustment can be calculated, and the total demand torque of the target vehicle is dynamically reduced and adjusted through the adjustment amount, so as to ensure that the vehicle still maintains a stable driving state in the slip state, and effectively prevent the vehicle from being in the power surplus state on the wet or uneven road surface, and improve the stability and safety of the vehicle. In the process of reducing the total demand torque, the total torque threshold is also calculated according to the vehicle adhesion coefficient, which is taken as the minimum value of the target total demand torque. It reflects the basic torque demand that the driving system must provide under the current adhesion condition, so it is necessary to ensure that the target total demand torque obtained by the reduction and adjustment is greater than the total torque threshold, so as to maintain effective driving force and driving stability.

[0110] Please refer to Figure 7 The process diagram of the total demand torque adjustment provided by the embodiment of the present application is shown in FIG. 1. In the total demand torque adjustment process, the vehicle controller will adopt the total demand torque adjustment strategy provided by the embodiment of the present application, estimate the vehicle adhesion coefficient, and estimate the target wheel speed of each wheel through the real vehicle speed, and realize the total demand torque adjustment enablement judgment in combination with the front and rear wheel speeds and the total demand torque, and output the updated total demand torque.

[0111] It is worth mentioning that the total demand torque adjustment method protected by the above embodiment of the present application can be synchronized with the front and rear axle torque adjustment method, that is, the embodiment of the present application can adjust the total demand torque before adjusting the front and rear axle torques of the target vehicle according to the total demand torque and the difference between the front and rear wheel speeds of the target vehicle, and obtain the updated target total demand torque, and then adjust the front and rear axle torques of the target vehicle based on the target total demand torque. In addition, the front and rear axle torque adjustment can also be performed first, and then the total demand torque is adjusted, which is not limited in the embodiment of the present application.

[0112] In a possible implementation, the embodiments of the present application also provide a single-axis torque adjustment mode. After the target vehicle is controlled by the front-rear axis torque adjustment and the total demand torque adjustment, if it is detected that the actual wheel speed of a certain axle is still greatly different from the target wheel speed, the single-axis torque adjustment mode can be used to control the torque of the single axle to further reduce the torque demand until the actual wheel speed of the axle is close to the target wheel speed, so that the driving force of each wheel is maximized on the basis of ensuring the adhesion of the wheel to the ground and avoiding slipping, thereby ensuring that the single axle can obtain the optimal torque support in complex working conditions and further improving the off-road performance and stability of the vehicle.

[0113] Referring to Figure 8 FIG. 8 shows a flowchart of another vehicle torque control method provided by the embodiments of the present application, which is used to adjust the single-axis demand torque of a single axle. The specific implementation process of the flowchart is as follows.

[0114] Step 801: Determine the target axle to be adjusted based on the current single-axis wheel speed and the target single-axis wheel speed of each axle.

[0115] In the embodiments of the present application, the current wheel speed of each axle, i.e., the current single-axis wheel speed, is obtained in real time by a sensor or the like. The current single-axis wheel speed of each axle is compared with the target wheel speed of each wheel calculated based on the actual speed of the target vehicle to determine the target axle to be adjusted.

[0116] Specifically, the current single-axis wheel speed represents the current left and right wheel speeds of the corresponding axle. Generally, the wheel speeds of the left and right wheels of the same axle and their target wheel speeds are the same. Therefore, the target wheel speed of the left / right wheel of the axle can be directly compared with the current single-axis wheel speed to determine whether the actual wheel speed of the axle is greatly different from the target wheel speed. If the actual wheel speed of the axle is greatly different from the target wheel speed, the axle is determined to be the target axle to be adjusted by the single-axis torque adjustment.

[0117] Step 802: Iteratively adjust the single-axis demand torque of the target axle based on the single-axis adhesion coefficient of the target axle until the difference between the current single-axis wheel speed and the target single-axis wheel speed of the target axle is less than a preset difference threshold.

[0118] In the embodiments of the present application, the single-axis torque adjustment of the single axle is similar to the total demand torque adjustment process described above, that is, the difference between the current single-axis wheel speed and the target single-axis wheel speed of the target axle is calculated, and the single-axis torque threshold corresponding to the single-axis demand torque is obtained according to the single-axis adhesion coefficient. Thus, the single-axis demand torque is reduced by combining the difference and the single-axis torque threshold until the difference between the current single-axis wheel speed and the target single-axis wheel speed of the target axle is less than the preset difference threshold.

[0119] In a possible implementation, the single-axle adhesion coefficient represents the grip between the target axle and the ground, and the average or maximum of the wheel adhesion coefficients of the left and right wheels of the target axle can be used as the single-axle adhesion coefficient of the target axle, which is not limited in the embodiments of the present application. In addition, the embodiments of the present application can use the PID control method to dynamically and accurately adjust the single-axle demand torque, so as to realize smooth and reliable vehicle driving. First, the difference between the current single-axle wheel speed of the target axle and the target single-axle wheel speed is calculated, and the difference is used as the input of the PID control, that is, the slip error, to reflect the slip state of the target single axle. Through the PID formula combined with the slip error, the adjustment amount of each single-axle demand torque adjustment can be calculated, and the single-axle demand torque of the target axle is dynamically adjusted by the adjustment amount. In the process of reducing the single-axle demand torque each time, the single-axle torque threshold is calculated according to the single-axle adhesion coefficient, which is used as the minimum value of the single-axle total demand torque, and it is ensured that the updated single-axle demand torque is greater than the single-axle torque threshold each time, until the difference between the current single-axle wheel speed of the target axle and the target single-axle wheel speed is less than the preset difference threshold, and the single-axle torque adjustment of the target axle is stopped.

[0120] Please refer to Figure 9 Fig. 1 shows a process diagram of single-axle torque adjustment provided by the embodiments of the present application. In the single-axle torque adjustment process, the single-axle adhesion coefficient of the target axle can be estimated by the foregoing determination method of the wheel adhesion coefficient, and the single-axle torque reduction enablement is judged by the vehicle controller, the current single-axle wheel speed, the single-axle target wheel speed, and the single-axle demand torque of the target axle are obtained in real time, and the single-axle torque adjustment method provided by the embodiments of the present application is used to output the updated single-axle demand torque.

[0121] Please refer to Figure 10 Fig. 2 shows an effect diagram of the front and rear axle torque equalization control under the related art, Figure 10 Fig. 2 shows an effect diagram of the front and rear axle torque equalization control under the related art, Figure 10 omega1-omega4 in Fig. 2 respectively represent the speeds of the left front wheel, the right front wheel, the left rear wheel, and the right rear wheel, from top to bottom. Figure 10 It can be seen that under the front and rear axle equalization control of the related art, the speeds of the front and rear axles of the vehicle are obviously not equal, and are in a state of alternating rising and falling in frequency, which represents poor stability of the vehicle driving. Referring to Figure 11 Fig. 3 shows an effect diagram of the vehicle torque control provided by the embodiments of the present application, Figure 11 Fig. 3 shows an effect diagram of the vehicle torque control provided by the embodiments of the present application, Figure 11 omega1-omega4 in Fig. 3 also respectively represent the speeds of the left front wheel, the right front wheel, the left rear wheel, and the right rear wheel, from top to bottom. Figure 11It can be seen that, by the vehicle torque control provided in the embodiments of the present application, the speed difference of the front and rear axles of the vehicle can be controlled, so that the moving speeds of the front and rear axles of the vehicle are equal, thereby ensuring that the slip ratios of the front and rear axles are consistent, and the vehicle driving force is particularly suitable for improving the off-road working conditions.

[0122] Based on the same inventive concept, the embodiments of the present application also provide a vehicle torque control device 12, which comprises:

[0123] The acquisition unit 1201 is configured to obtain a corresponding front and rear wheel speed difference based on the front and rear axle wheel speeds of the target vehicle, wherein the front and rear axle wheel speeds represent the front axle wheel speed and the rear axle wheel speed of the corresponding vehicle.

[0124] The determination unit 1202 is configured to determine whether the target vehicle meets a preset torque adjustment condition based on the front and rear wheel speed difference and the vehicle driving state.

[0125] The adjustment unit 1203 is configured to adjust the front and rear axle torques of the target vehicle based on the total demand torque of the target vehicle and the front and rear wheel speed difference to obtain target front and rear axle torques when the target vehicle meets the torque adjustment condition.

[0126] Optionally, the torque adjustment condition comprises that the front and rear wheel speed difference is greater than a wheel speed difference threshold value, and the vehicle driving state is a driving state.

[0127] Optionally, the adjustment unit 1203 is specifically configured to:

[0128] When the front and rear wheel speed difference is greater than the wheel speed difference threshold value, a current torque ratio of the target vehicle is obtained, wherein the current torque ratio represents a ratio between the current front axle torque and the current rear axle torque of the corresponding vehicle.

[0129] The current torque ratio is proportionally adjusted based on a preset proportion allocation strategy until the target vehicle meets an adjustment termination condition to obtain a target torque ratio, wherein the adjustment termination condition represents that the front and rear wheel speed difference is less than the wheel speed difference threshold value.

[0130] The target front and rear axle torques are obtained based on the target torque ratio and the total demand torque.

[0131] Optionally, the adjustment unit 1203 is further configured to:

[0132] The vehicle adhesion coefficient is obtained based on the wheel driving state of the target vehicle, wherein the vehicle adhesion coefficient represents the grip force between the corresponding vehicle and the ground, and the wheel driving state comprises the driving force and the slip state of each wheel of the corresponding vehicle.

[0133] The target wheel speed of each wheel is obtained based on the actual speed of the target vehicle.

[0134] The total demand torque is adjusted based on the front and rear axle wheel speeds, the target wheel speeds of the target vehicle, and the vehicle adhesion coefficient to obtain a target total demand torque when the front and rear axles of the target vehicle are in a slipping state.

[0135] Optionally, the adjusting unit 1203 is specifically used for:

[0136] Based on the average wheel speed of the front and rear axle wheel speeds, a difference between the average wheel speed and the target wheel speed is obtained.

[0137] Based on the vehicle adhesion coefficient, a total torque threshold corresponding to the total demand torque is obtained.

[0138] Based on the difference and the total torque threshold, the total demand torque is reduced to obtain a target total demand torque, and the target total demand torque is greater than the total torque threshold.

[0139] Optionally, the adjusting unit 1203 is specifically used for:

[0140] The driving force and the normal pressure corresponding to each wheel are obtained, and the normal pressure represents the pressure between the corresponding wheel and the ground in the vertical direction.

[0141] For each wheel, when it is determined that the wheel is in a non-slip state, the wheel adhesion coefficient corresponding to each wheel is obtained based on the driving force and the normal pressure of each wheel, and the wheel adhesion coefficient represents the grip between the corresponding wheel and the ground.

[0142] Based on the relative size relationship between the wheel adhesion coefficients, the maximum wheel adhesion coefficient is taken as the vehicle adhesion coefficient.

[0143] Optionally, the adjusting unit 1203 is further used for:

[0144] Based on the current single axle speed and the target single axle speed of each axle, a target axle to be adjusted is determined, the current single axle speed represents the current left and right wheel speeds of the corresponding axle, and the target single axle speed is determined based on the actual speed of the target vehicle.

[0145] Based on the single axle adhesion coefficient of the target axle, the single axle demand torque of the target axle is iteratively adjusted until the difference between the current single axle speed and the target single axle speed of the target axle is less than a preset difference threshold, and the single axle adhesion coefficient represents the grip between the corresponding axle and the ground.

[0146] Optionally, each iteration adjustment process includes:

[0147] Based on the difference between the current single axle speed and the target single axle speed, a single axle adjustment difference corresponding to the target axle is obtained.

[0148] Based on the single axle adhesion coefficient, a single axle torque threshold of the target axle is obtained.

[0149] Based on the single-axis adjustment difference value and the single-axis torque threshold value, the single-axis demand torque is reduced to obtain a target single-axis demand torque, and the target single-axis demand torque is greater than the single-axis torque threshold value.

[0150] For the convenience of description, the above parts are divided into unit modules (or modules) according to functions and are described respectively. Of course, the functions of the units (or modules) can be implemented in the same or more software or hardware in the implementation of the present application. Those skilled in the art can understand that each aspect of the present application can be implemented as a system, a method or a program product. Therefore, each aspect of the present application can be specifically implemented as a complete hardware implementation, a complete software implementation (including firmware, microcode, etc.), or a combination of hardware and software aspects, which can be collectively referred to as "circuit", "module" or "system" here.

[0151] The apparatus can be used to execute the method shown in each embodiment of the present application, and the functions and the like that can be achieved by each functional module of the apparatus can be referred to the description of the foregoing embodiments, and will not be described in detail.

[0152] Please refer to Figure 13 As shown, based on the same technical concept, the present application also provides a computer device 130, which can be a server, a personal computer, a terminal, a network device, a mobile phone, a tablet computer, a wearable device, or the like. Figure 3 As shown in the vehicle torque control system, the computer device 130 can include a memory 1301 and a processor 1302.

[0153] The so-called memory 1301 is used to store the computer program executed by the processor 1302. The memory 1301 can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application required by a function, and the like; the data storage area can store data created according to the use of the computer device, and the like. The processor 1302 can be a central processing unit (CPU) or a digital processing unit, and the like. The specific connection medium between the memory 1301 and the processor 1302 is not limited in the present application. In the present application, the memory 1301 and the processor 1302 are connected through a bus 1303, and the connection mode between other components is only schematically illustrated and is not limited. The so-called bus 1303 can be divided into an address bus, a data bus, a control bus, and the like. For the convenience of representation, only one thick line is used in the present application, but it does not mean that there is only one bus or only one type of bus. Figure 4 Figure 4 Figure 13

[0154] ​​​The memory 1301 can be a volatile memory (volatile memory), such as a random access memory (RAM); the memory 1301 can also be a non-volatile memory (non-volatile memory), such as a read-only memory, a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD), or the memory 1301 is any other medium capable of carrying or storing desired program code in the form of instructions or data structures and capable of being accessed by a computer, but not limited to this. The memory 1301 can be a combination of the above-mentioned memories.

[0155] The processor 1302 is configured to invoke the computer program stored in the memory 1301 to perform the vehicle torque control method performed by the device in the embodiments of the present application.

[0156] In some possible implementation manners, various aspects of the vehicle torque control method provided by the present application can also be implemented in the form of a program product, which includes program codes for causing a computer device to perform the steps of the vehicle torque control method according to various exemplary embodiments of the present application described above in the specification when the program product is run on the computer device, for example, the computer device can perform the steps of the embodiments.

[0157] The program product can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium may, for example, be but is not limited to an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or apparatus, or any combination of the above. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection having one or more wires, a portable 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.

[0158] The program product of the embodiments of the present application can adopt a portable compact disk read-only memory (CD-ROM) and include program codes, and can be run on a computing device. However, the program product of the present application is not limited to this, in the present application, the readable storage medium can be any tangible medium containing or storing programs, which can be used or combined with a command execution system, device or apparatus.

[0159] A readable signal medium can be any available medium or media that can be accessed by a general purpose or special purpose computing system, device or apparatus to retrieve instructions to implement the operations. By way of example, such a medium can comprise a random access memory (RAM), a read-only memory (ROM), an optical disk, a magnetic disk, or other storage medium 625 from which a computer or computing system can read instructions. The readable signal medium can also be a collection of such mediums 625 in which instructions are stored.

[0160] The program code embodied on the readable medium can be transmitted using any appropriate medium, including but not limited to wireless, wired, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0161] The program code can be executed by one or more programmable processors, which can be individually, or collectively, programmed to perform the operations described above. The program code can be implemented in any desired language, including C, C++, Java, Visual Basic, Java, Python, HTML, and / or machine language. The program code can be stored in any desired form, including source code, object code, interpreted code, and / or machine code, and can be stored in any desired location, including computer memory locations, on a computer storage medium, and / or on a computer storage medium.

[0162] It should be noted that, although the foregoing detailed description has set forth numerous specific details, it is understood that implementations of the present application might be practiced without these specific details. That is, there is no need for an apparatus to conform to the details set forth herein, and not all implementations have to exhibit all of the described features. For example, the apparatus can be implemented in a variety of ways. In addition, it is also contemplated that software implemented aspects of the application can be implemented in conjunction with any other software implemented aspects or hardware-implemented aspects of the application not specifically described herein. Furthermore, although the example methods have been described in some detail, it is understood that the methods can be practiced in a variety of ways. For example, the methods can be practiced in a different order than the order described. Additionally, some steps can be performed in parallel rather than sequentially. Also, some steps can be omitted, some steps can be combined, and some steps can be performed by hardware rather than software.

[0163] In addition, although the operations of the method(s) have been described in a particular, sequential order, this order is not the only order in which the operations can be performed. For example, the operations can be performed in parallel, or in a different order than that described. One or more of the operations can be repeated, or omitted, or combined with other operations. Additionally, one or more of the operations can be performed by a different entity than the entity described.

[0164] Those skilled in the art will appreciate that embodiments of the present application can be devised for a method, a system, or a computer program product. Accordingly, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application can take the form of a computer program product on one or more computer readable storage media (including, but not limited to, disk storage, CD-ROMs, optical storage devices, etc.) embodying computer readable program code thereon for use by or in connection with an instruction execution system. For the purposes of this description, a computer usable or computer readable storage medium can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device.

[0165] Although preferred embodiments of the application have been described herein, those skilled in the art will appreciate that other changes and modifications can be made to the embodiments described without departing from the spirit and scope of the application. It is therefore intended that the appended claims encompass all such changes and modifications as fall within the scope of the application.

[0166] Obviously, numerous modifications and variations of the present application are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A vehicle torque control method characterized by, The method comprises: obtaining a corresponding front-rear wheel speed difference based on front-rear axle wheel speeds of a target vehicle, the front-rear axle wheel speeds representing front axle wheel speeds and rear axle wheel speeds of the corresponding vehicle; judging whether the target vehicle satisfies a preset torque adjustment condition based on the front-rear wheel speed difference and a vehicle driving state; adjusting front-rear axle torques of the target vehicle based on a total demand torque of the target vehicle and the front-rear wheel speed difference to obtain target front-rear axle torques when the target vehicle satisfies the torque adjustment condition; obtaining a vehicle adhesion coefficient based on a wheel driving state of the target vehicle, the vehicle adhesion coefficient representing a grip force between the corresponding vehicle and the ground; the wheel driving state comprises driving forces and slip states of each wheel of the corresponding vehicle; obtaining target wheel speeds of the each wheel based on an actual speed of the target vehicle; obtaining a difference value between the average wheel speed and the target wheel speed based on an average wheel speed of the front-rear axle wheel speeds when the front-rear axle of the target vehicle is in a slip state; obtaining a total torque threshold corresponding to the total demand torque based on the vehicle adhesion coefficient; reducing the total demand torque based on the difference value and the total torque threshold to obtain a target total demand torque, the target total demand torque being greater than the total torque threshold.

2. The method of claim 1, wherein, The torque adjustment condition comprises that the front-rear wheel speed difference is greater than a wheel speed difference threshold and the vehicle driving state is a driving state.

3. The method of claim 2, wherein, The adjusting of the front-rear axle torques of the target vehicle based on the total demand torque of the target vehicle and the front-rear wheel speed difference to obtain target front-rear axle torques comprises: obtaining a current torque ratio of the target vehicle when the front-rear wheel speed difference is greater than the wheel speed difference threshold, the current torque ratio representing a ratio between a current front axle torque and a current rear axle torque of the corresponding vehicle; proportionally adjusting the current torque ratio based on a preset proportion allocation strategy until the target vehicle satisfies an adjustment termination condition to obtain a target torque ratio, the adjustment termination condition representing that the front-rear wheel speed difference is less than the wheel speed difference threshold; obtaining target front-rear axle torques based on the target torque ratio and the total demand torque.

4. The method of claim 1, wherein, The obtaining of the vehicle adhesion coefficient based on the wheel driving state of the target vehicle comprises: obtaining respective driving forces and normal pressures of each wheel, the normal pressure representing a pressure between the corresponding wheel and the ground in a vertical direction; respectively for each wheel, obtaining a respective wheel adhesion coefficient of each wheel based on the respective driving force and the normal pressure of each wheel when it is determined that the wheel is in a non-slip state, the wheel adhesion coefficient representing a grip force between the corresponding wheel and the ground; taking a maximum wheel adhesion coefficient as the vehicle adhesion coefficient based on a relative size relationship between the wheel adhesion coefficients.

5. The method of claim 1, wherein, After obtaining the updated target front-rear axle torques, the method further comprises: determine a target axle to be adjusted based on a current single-axle wheel speed and a target single-axle wheel speed of each axle, the current single-axle wheel speed representing a current left and right wheel speed of the corresponding axle, and the target single-axle wheel speed being determined based on an actual vehicle speed of the target vehicle; iteratively adjust a single-axle required torque of the target axle based on a single-axle adhesion coefficient of the target axle until a difference between the current single-axle wheel speed and the target single-axle wheel speed of the target axle is less than a preset difference threshold, the single-axle adhesion coefficient representing a grip force between the corresponding axle and the ground.

6. The method of claim 5, wherein, Each iteration adjustment process includes: obtain a single-axle adjustment difference value corresponding to the target axle based on a difference between the current single-axle wheel speed and the target single-axle wheel speed; obtain a single-axle torque threshold of the target axle based on the single-axle adhesion coefficient; reduce the single-axle required torque based on the single-axle adjustment difference value and the single-axle torque threshold to obtain a target single-axle required torque, the target single-axle required torque being greater than the single-axle torque threshold.

7. A vehicle torque control device characterized by comprising: The device includes: an obtaining unit configured to obtain a corresponding front-rear wheel speed difference based on front-rear axle wheel speeds of a target vehicle, the front-rear axle wheel speeds representing front axle wheel speeds and rear axle wheel speeds of the corresponding vehicle; a judging unit configured to judge whether the target vehicle meets a preset torque adjustment condition based on the front-rear wheel speed difference and a vehicle driving state; an adjusting unit configured to adjust front-rear axle torques of the target vehicle based on a total required torque of the target vehicle and the front-rear wheel speed difference to obtain target front-rear axle torques when the target vehicle meets the torque adjustment condition; obtain a vehicle adhesion coefficient based on a wheel driving state of the target vehicle, the vehicle adhesion coefficient representing a grip force between the corresponding vehicle and the ground, and the wheel driving state including driving forces and slip states of each wheel of the corresponding vehicle; obtain target wheel speeds of the wheels based on an actual vehicle speed of the target vehicle; obtain a difference between a wheel speed average value and the target wheel speed based on the wheel speed average value of the front-rear axle wheel speeds when the front-rear axles of the target vehicle are in the slip state; obtain a total torque threshold corresponding to the total required torque based on the vehicle adhesion coefficient; reduce the total required torque based on the difference and the total torque threshold to obtain a target total required torque, the target total required torque being greater than the total torque threshold.

8. A computer device, comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, characterized in that: the processor implements the steps of the method of any one of claims 1 to 6 when executing the computer program.

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