Vehicle driving control system and method, storage medium and computer program product

Abstract

The invention discloses a vehicle driving control system and method, a storage medium and a computer program product. The system comprises a static load calculation module, a wheel load calculation module, a load variation coefficient calculation module and a wheel end torque adjustment module. Through a complete control logic chain of load sensing, proportion calculation, torque distribution and intention keeping, normal form conversion from mechanical passive adjustment to electromechanical active control is achieved, and a brand new technical path is provided for attitude control of the wheel-side-driven vehicle. While the driving comfort and safety are improved, response delay and function limitation of a traditional suspension system are avoided, and remarkable engineering application value and technical perspectiveness are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of automotive electronics, and particularly relates to a vehicle driving control system, method, storage medium, and computer program product. Background Art

[0002] When a vehicle is driving on an uneven road or on an uphill or downhill slope, the vehicle will pitch and / or roll, resulting in a change in the vehicle's attitude. The center of gravity of the driver also changes along with the center of gravity of the vehicle, and the driver's attitude will shift. At the same time, the driver's field of vision will also be affected. These not only affect the ride comfort but may even affect the driving safety of the vehicle. Currently, some high-level vehicles improve pitching and rolling by adjusting the suspension or the anti-roll bar. However, due to the slow response of the suspension adjustment, the anti-roll bar can only improve rolling. In emergency situations, such as sudden deceleration or avoiding obstacles, due to the slow response of the suspension adjustment, the pitching angle of the vehicle cannot be adjusted in time, which is extremely likely to cause the front of the vehicle to sink excessively or the rear of the vehicle to lift, destroying the dynamic balance of the vehicle and even triggering a risk of out-of-control. At the same time, relying solely on the anti-roll bar to improve rolling makes the vehicle lack effective control of the longitudinal pitching attitude when driving on uphill and downhill slopes, significantly increasing the driver's blind spot of vision and greatly reducing the ability to predict road conditions, seriously threatening driving safety. In addition, due to the limitations of the adjustment functions of the suspension and the stabilizer bar, when the vehicle frequently encounters complex road conditions, each component bears uneven stress, accelerating aging and wear, not only greatly increasing the maintenance cost but also shortening the overall service life of the vehicle. Moreover, the response lag and the insufficiency of the adjustment function lead to frequent body shaking and unstable attitude during the ride, seriously affecting the comfort and making it difficult to meet the expectations of users for a high-end travel experience. Summary of the Invention

[0003] To solve the problems described in the background art, the present invention proposes a vehicle driving control system, method, storage medium, and computer program product.

[0004] A vehicle driving control system for achieving one of the purposes of the present invention includes:

[0005] A static load calculation module: used to calculate the static load of each tire of the vehicle according to the longitudinal acceleration, lateral acceleration, road slope, and the vehicle's own parameters; the vehicle's own parameters include: sprung mass, the distance from the center of gravity to the front and rear axles, wheelbase, and center of gravity height.

[0006] A wheel load calculation module: used to calculate the wheel load of each wheel according to the static load during vehicle driving and the load transfer amounts in the transverse and longitudinal directions;

[0007] A load change coefficient calculation module: used to calculate the load change coefficient according to the change amount of the wheel load of each wheel;

[0008] Wheel-end torque adjustment module: used to calculate the wheel-end target torque of each wheel at the current moment according to the load change coefficient, and control the vehicle drive or braking system according to the wheel-end target torque of each wheel at the current moment.

[0009] Further, the calculation method of the wheel-end target torque of each wheel at the current moment includes:

[0010] When the vehicle is driving: T i_Tar = T i_Cur (1 + K i );

[0011] When the vehicle is braking: T i_Tar = T Cur (1 - K i );

[0012] In the formula, T i_Tar represents the wheel-end target torque of the i-th wheel at the current moment, T i_cur represents the wheel-end torque of the i-th wheel at the previous moment; K i represents the load change coefficient of the i-th wheel.

[0013] Further, the method for calculating the load change coefficient of each wheel includes:

[0014]

[0015] In the formula, F lf_s , F lr_s , F rf_s , F rr_s are the wheel loads of the left front, left rear, right front, and right rear tires at rest respectively; m is the sprung mass; a is the distance from the center of mass to the front axle; b is the distance from the center of mass to the rear axle; l is the wheelbase, h is the height of the center of mass, and α is the longitudinal slope value.

[0016] The technical effects of the above calculation of wheel load include: comprehensively considering various factors such as the longitudinal acceleration, lateral acceleration, vehicle's own parameters, and road slope of the vehicle, more accurately obtaining the wheel loads of each wheel of the vehicle under different driving conditions, and providing a reliable basis for the precise adjustment of the subsequent wheel-end torque. For example: when the vehicle is turning, the lateral acceleration will cause the wheel loads to change, and the load change coefficient calculated in combination with other factors can enable the system to more accurately adjust the drive or braking torque of each wheel, reduce the risk of vehicle roll, and improve the handling performance and driving safety of the vehicle.

[0017] The calculation methods of the longitudinal load transfer and lateral load transfer of the vehicle include:

[0018]

[0019] In the formula, t is the track width; w xand w y are the longitudinal load transfer amount and the lateral load transfer amount respectively; a x and a y are the longitudinal acceleration and the lateral acceleration respectively; m is the sprung mass; h is the height of the center of mass; l is the wheelbase.

[0020] The calculation method of the wheel load of each wheel includes:

[0021] F lf_t = F lf_s - sgn(a x ) × |w x | - sgn(a y ) × |w y |

[0022] F lr_t = F lr_s + sgn(a x ) × |w x | - sgn(a y ) × |w y |

[0023] F rf_t = F rf_s - sgn(a x ) × |w x | + sgn(a y ) × |w y |

[0024] F rr_t = F rr_s + sgn(a x ) × |w x | + sgn(a y ) × |w y |

[0025] In the formula, F lf_t , F lr_t , F rf_t , F rr_t are the wheel loads of the left front, left rear, right front, and right rear tires respectively; a x is the longitudinal acceleration of the vehicle, positive forward and negative backward; a y is the lateral acceleration, positive to the left and negative to the right; w x is the longitudinal load transfer amount; w y is the lateral load transfer amount.

[0026] Furthermore, since the slope and acceleration are different at different moments when the vehicle is running, the calculation formula of the wheel load change coefficient K i includes:

[0027] K i=(Wheel load at the current moment - Wheel load at the previous moment) / Wheel load at the previous moment

[0028] The calculation method of the wheel load change coefficient for each wheel is as follows:

[0029]

[0030]

[0031] In the formula, K lf ,K lr ,K rf ,K rr are the load change coefficients of the left front, left rear, right front, and right rear tires respectively; F lf_t1 ,F lr_t1 ,F rf_t1 ,F rr_t1 are the wheel loads of the left front, left rear, right front, and right rear tires of the vehicle at the previous moment respectively; F lf_t2 ,F lr_t2 ,F rf_t2 ,F rr_t2 are the wheel loads of the left front, left rear, right front, and right rear tires of the vehicle at the current moment respectively.

[0032] In this step, the complex dynamic change of the wheel load (affected by slope and acceleration) is transformed into a dimensionless proportional load change coefficient K, enabling unified mathematical benchmarks for torque adjustment under different working conditions (driving / braking) and different vehicle models (differences in centroid parameters); traditional methods require designing independent torque distribution rules for different scenarios (such as the wheel speed difference threshold of ABS and the yaw rate feedback of ESC), while the K value realizes a general control logic through the relative proportion of wheel load changes, enabling the torque adjustment strategy to dynamically adapt to the current driving state of the vehicle, which cannot be achieved by traditional fixed-ratio distribution.

[0033] Further, when the vehicle is driving, if the target torque at the wheel ends of each wheel is negative, the corresponding motor is controlled for electric braking. If it exceeds the minimum torque value of the motor, the corresponding wheel side braking force is controlled to supplement. Its technical effects include: when the target torque at the wheel ends of each wheel is negative, it indicates that the actual demand of the vehicle is opposite to the conventional torque output direction in the driving state. It may be that the driver performs a deceleration operation, or the vehicle is in a special working condition and needs braking. At this time, the motor is controlled for electric braking, and the resistance generated by the reverse rotation of the motor is used to convert the kinetic energy of the vehicle into electrical energy for recycling. This not only realizes the braking function but also can charge the vehicle's battery, improving the energy utilization efficiency. When the vehicle is going downhill, the motor can generate a reverse torque through electric braking, limit the vehicle speed while recovering energy, reduce the vehicle's dependence on the traditional braking system, and reduce the wear of braking components. On the other hand, the torque output ability of the motor has a certain range. When the target torque at the wheel ends of each wheel exceeds the minimum torque value of the motor, it means that the motor cannot provide enough braking torque. If only relying on electric braking, the braking effect will be affected and the vehicle braking demand cannot be met. By controlling the corresponding wheel side braking force to supplement, it can ensure that the vehicle obtains sufficient braking force; in emergency braking or high-speed driving braking, the timely supplement of the wheel side braking force can effectively shorten the braking distance and avoid accidents.

[0034] Further, when the vehicle is braking, the braking system is controlled according to the target torque at the wheel ends of each wheel at the current moment. If the target torque at the wheel ends of each wheel exceeds the maximum limit of the wheel side braking system, the corresponding wheel side drive motor is controlled to supplement through electric braking. Its technical effects include: when the target torque at the wheel ends of each wheel exceeds the maximum limit of the wheel side braking system, it indicates that relying solely on the wheel side braking system cannot fully meet the braking demand. If the pressure of the wheel side braking system is continuously increased, it may cause the braking system to overheat, the brake pads to wear more severely, and even brake failure. At this time, by controlling the corresponding wheel side drive motor for electric braking to supplement, the braking capacity of the motor is used to share part of the braking load and reduce the pressure on the wheel side braking system. This helps to extend the service life of the braking system and improve the stability and reliability of the braking system. On continuous long downhill sections, the supplement of electric braking can reduce the burden on the wheel side braking system and prevent its performance from degrading due to overheating.

[0035] A vehicle driving control method for achieving the second object of the present invention includes:

[0036] Calculating the static loads of each tire of the vehicle according to the longitudinal acceleration, lateral acceleration, road slope and the vehicle's own parameters;

[0037] Calculating the wheel loads of each wheel according to the static loads during vehicle driving and the load transfer amounts in the longitudinal and lateral directions;

[0038] Calculating the load change coefficient according to the change amounts of the wheel loads of each wheel;

[0039] Calculate the target torque at the wheel ends of each wheel at the current moment according to the load change coefficient, and control the vehicle drive or braking system according to the target torque at the wheel ends of each wheel at the current moment.

[0040] A non-transitory computer-readable storage medium for achieving the third object of the present invention, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the vehicle driving control method are implemented.

[0041] A computer program product for achieving the fourth object of the present invention, including computer programs / instructions, and when the computer programs / instructions are executed by a processor, the steps of the vehicle driving control method are implemented.

[0042] The beneficial effects of the present invention include:

[0043] 1. Compared with the prior art (such as adjusting the suspension or anti-roll bar) that relies on the passive response of mechanical structures, the present invention realizes the active distribution of wheel-end torque, and the response speed can reach the millisecond level, far exceeding the second-level response of the suspension system.

[0044] 2. Compared with the prior art in which it is difficult to accurately control the torque of a single wheel in a traditional central drive vehicle, the present invention, aiming at the distributed control characteristics of in-wheel motors / brakes, realizes independent and accurate adjustment of the four wheels through the load change coefficient.

[0045] 3. The present invention realizes the paradigm conversion from "mechanical passive adjustment" to "electromechanical active control" through a complete control logic chain of "load sensing → proportional calculation → torque distribution → intention maintenance", providing a new technical path for the attitude control of in-wheel drive vehicles. While improving the ride comfort and safety, it avoids the response delay and functional limitations of the traditional suspension system, and has significant engineering application value and technological foresight. Description of the Drawings

[0046] Figure 1 is a schematic flow chart of an embodiment of the method of the present invention;

[0047] Figure 2 is a schematic diagram of the force analysis of the vehicle on a slope;

[0048] Figure 3 is a schematic diagram of an embodiment of the system of the present invention. Detailed Embodiments

[0049] The following detailed embodiments are used to explain the technical solutions of the present invention so that those skilled in the art can understand the present invention. The protection scope of the present invention is not limited to the following specific implementation structures. Those made by those skilled in the art that include the technical solutions of the present invention and are different from the following specific embodiments are also within the protection scope of the present invention.

[0050] A vehicle driving control method

[0051] Step 1: Obtain vehicle-related information

[0052] Obtain the longitudinal and lateral accelerations a x and a y , slope value α, and various vehicle parameters, including: sprung mass m; distance a from the vehicle's center of mass to the front axle; distance b from the vehicle's center of mass to the rear axle; wheelbase l, center of mass height h, and during vehicle driving, estimate in real time the vertical forces (i.e., wheel loads) on the four tires, as Figure 2 shown

[0053] Step 2: Calculate the wheel loads of the tires

[0054] Estimate the wheel loads of the tires based on the vehicle load transfer model, and consider the road slope and the change in the vehicle's total mass. The input is the longitudinal acceleration, lateral acceleration, vehicle's own parameters, and road slope, and the output is the wheel loads of the four tires

[0055] Step 2.1: Calculate the static load

[0056] First, calculate the static loads of the four tires according to the position of the center of mass of the sprung mass and the slope value

[0057] When the vehicle is driving on a slope, calculate the static loads of the four tires according to the following formulas (1) to (4):

[0058]

[0059] Among them, F lf_s , F lr_s , F rf_s , F rr_s are the wheel loads of the left front, left rear, right front, and right rear tires at static respectively; m is the sprung mass; a is the distance from the center of mass to the front axle; b is the distance from the center of mass to the rear axle; l is the wheelbase, h is the center of mass height, and α is the longitudinal slope value. The calculation of the above wheel loads does not distinguish between longitudinal and transverse slopes, that is, it does not distinguish the influence of longitudinal slope and transverse slope on the left and right tire loads, and only considers the influence of longitudinal slope α on the front and rear axle loads

[0060] When the vehicle is driving on a flat road, that is, the longitudinal slope value α is 0, the wheel loads of the four tires at static are:[[]]

[0061]

[0062] Among them, F lf_o , F lr_o , F rf_o , F rr_o are the static loads of the left front, left rear, right front, and right rear tires on a flat road respectively

[0063] The above calculation formula takes into account the influence of vehicle own parameters (such as sprung mass m, center of mass position, etc.) and road gradient on the static load of the tire.

[0064] Step 2.2, Calculate the load transfer amount

[0065] The longitudinal and lateral load transfer amounts caused by longitudinal and lateral accelerations, and their calculation methods include:

[0066]

[0067] where t is the track width; w x and w y are the longitudinal load transfer amount and the lateral load transfer amount respectively. The longitudinal load transfer amount is the change amount of the front / rear axle load caused by the longitudinal acceleration a x ; the front axle load decreases by w x , and the rear axle load increases by w x (the rear axle load increases during acceleration, and the front axle load increases during deceleration); the lateral load transfer amount is the change amount of the front / rear axle load caused by the lateral acceleration a y ; the left axle load decreases by w y , and the right axle load increases by w y (the outer wheel load increases during steering).

[0068] Step 2.3, Calculate the wheel load of each tire

[0069] Combining the influence of gradient and acceleration, based on the static load and the longitudinal and lateral load transfer amounts w x and w y , calculate the wheel load of each wheel. The specific calculation method includes:

[0070] F lf_t = F lf_s - sgn(a x ) × |w x | - sgn(a y ) × |w y | Equation (11)

[0071] F lr_t = F lr_s + sgn(a x ) × |w x | - sgn(a y ) × |w y | Equation (12)

[0072] F rf_t = F rf_s - sgn(a x ) × |w x | + sgn(ay )×|w y | Equation (13)

[0073] F rr_t = F rr_s + sgn(a x )×|w x |+ sgn(a y )×|w y | Equation (14)

[0074] Longitudinal vehicle acceleration a x is positive forward and negative backward; Lateral acceleration a y is positive to the left and negative to the right.

[0075] Taking the vehicle accelerating forward longitudinally and accelerating to the left laterally as an example, the inertial force at the center of mass position of the vehicle will cause the load at the front of the vehicle to decrease and the load at the rear to increase at this time. The load transfer amount between the front and rear axles is the longitudinal load transfer amount w x , so the load at the rear of the vehicle increases by the longitudinal load transfer amount w x and the load at the front decreases by the longitudinal load transfer amount w x ; When the vehicle accelerates to the left laterally, the vehicle will be subjected to an inertial force to the right, resulting in an increase in the load on the right side of the vehicle and a decrease in the load on the left side. The load transfer amount between the left and right axles is the lateral load transfer amount w y ; It will cause the load on the right side of the vehicle to increase by the lateral load transfer amount w y and the load on the left side to decrease by the lateral load transfer amount w y , and finally the estimated values of the wheel loads of the four wheels when the vehicle is driving are calculated as follows:

[0076] F lf_t = F lf_s - w x - w y Equation (15)

[0077] F lr_t = F lr_s + w x - w y Equation (16)

[0078] F rf_t = F rf_s - w x + w y Equation (17)

[0079] F rr_t = F rr_s + w x + w y Equation (18)

[0080] Among them, F lf_t , F lr_t, F rf_t , F rr_t are the wheel loads of the left front, left rear, right front, and right rear tires respectively.

[0081] Step 3: Calculate the load change coefficient

[0082] Calculate the wheel load change coefficient according to the following formula:

[0083]

[0084] where K lf , K lr , K rf , K rr are the ratios of the load changes of the left front, left rear, right front, and right rear tires to the wheel loads at the previous moment, that is, the load change coefficients, which are used to reflect the deviation degree of the current load from the load at the previous moment and are used to guide torque adjustment. F lf_t1 , F lr_t1 , F rf_t1 , F rr_t1 are the wheel loads of the left front, left rear, right front, and right rear tires at the previous moment; F lf_t2 , F lr_t2 , F rf_t2 , F rr_t2 are the wheel loads of the left front, left rear, right front, and right rear tires of the vehicle at the current moment.

[0085] Step 4: Adjust the wheel end torque

[0086] Dynamically adjust the wheel end torque according to the wheel load ratios

[0087] When the vehicle is driving:

[0088] For example, when accelerating or / and going uphill, the vehicle load moves backward. At this time, if the torque distribution is not adjusted, the vehicle will lift its head; therefore, it is necessary to appropriately transfer the driving torque to the rear axle to suppress the vehicle from lifting its head. At this time, the front wheel K i < 0, and the rear wheel K i > 0, that is, reduce the front wheel torque and increase the rear wheel torque. Another example is when decelerating or / and going downhill, the load moves forward, and it is necessary to appropriately transfer the driving torque to the front axle to suppress the vehicle from lowering its head; at this time, the front wheel K i > 0, and the rear wheel K i < 0, that is, increase the front wheel torque and reduce the rear wheel torque.

[0089] Then when the vehicle is driving, the calculation formula for the adjusted wheel end torque (that is, the wheel end target torque of each wheel at the current moment) is:

[0090] T lf_Tar = T lf_Cur *(1 + K lf) Equation (23)

[0091] T lr_Tar = T lr_Cur *(1 + K lr ) Equation (24)

[0092] T rf_Tar = T rf_Cur *(1 + K rf ) Equation (25)

[0093] T rr_Tar = T rr_Cur *(1 + K rr ) Equation (26)

[0094] Wherein, T lf_Cur , T lr_Cur , T rf_Cur , T rr_Cur are the left front, left rear, right front, and right rear wheel-end torques at the previous moment respectively, and T lf_Tar , T lr_Tar , T rf_Tar , T rr_Tar are the left front, left rear, right front, and right rear wheel-end target torques at the current moment respectively;

[0095] When the vehicle is driving, the calculated wheel-end target torques of each wheel at the current moment are used to control the wheel-end motors respectively. The wheel-end motor torque cannot exceed the maximum limit of the motor. If the calculated wheel-end target torque is negative, the corresponding motor is controlled for electric braking. If it exceeds the minimum torque value of the motor, the corresponding wheel-side braking force is supplemented through control.

[0096] When the vehicle is braking:

[0097] For example, when the deceleration decreases (such as reducing braking or going uphill), the load moves backward. If the torque distribution is not adjusted, the vehicle will lift its head. To suppress the vehicle from lifting its head, the braking torque is appropriately transferred to the front axle. At this time, the front-wheel K i < 0, and the rear-wheel K i > 0, that is, the front-wheel torque is increased and the rear-wheel torque is decreased. Another example is when the deceleration increases (such as increasing braking or going downhill), the load moves forward. If the torque distribution is not adjusted, the vehicle will lower its head. To suppress the vehicle from lowering its head, the braking torque is appropriately transferred to the rear axle. At this time, the front-wheel K i > 0, and the rear-wheel K i < 0, so the front-wheel torque is decreased and the rear-wheel torque is increased. Similarly, when turning or on a side slope, the load moves left and right, and the left and right torques are adjusted to suppress the vehicle roll.

[0098] Then the adjusted wheel-end torques of each wheel during vehicle braking are:

[0099] T lf_Tar = Tlf_Cur *(1 - K lf ) Equation (27)

[0100] T lr_Tar = T lr_Cur *(1 - K lr ) Equation (28)

[0101] T rf_Tar = T rf_Cur *(1 - K rf ) Equation (29)

[0102] T rr_Tar = T rr_Cur *(1 - K rr ) Equation (30)

[0103] where T lf_Cur , T lr_Cur , T rf_Cur , T rr_Cur are the torques at the left front, left rear, right front, and right rear wheel ends at the previous moment respectively, and T lf_Tar , T lr_Tar , T rf_Tar , T rr_Tar are the target torques at the left front, left rear, right front, and right rear wheel ends at the current moment respectively.

[0104] When the vehicle is braking, the calculated target torques at the wheel ends of each wheel at the current moment are used to control the wheel-end hydraulic braking or the wire-controlled braking system respectively. The controlled torque cannot exceed the maximum limit of the wheel-side braking system. If it exceeds the maximum limit, the corresponding wheel-side drive motor is controlled to supplement through electric braking;

[0105] To not change the driver's driving intention, the sum of the torques at each wheel side after adjustment is equal to the sum of the torques at each wheel side before adjustment. Only the torque distribution among the four wheel ends is adjusted according to the load change coefficient K, that is:

[0106] T lf_Tar + T lr_Tar + T rf_Tar + T rr_Tar = T lf_Cur + T lr_Cur + T rf_Cur + T rr_Cur Equation (31)

[0107] The technical solution of the present invention improves the vehicle pitch, roll, and yaw by controlling the wheel-end torque, thereby improving the vehicle comfort and enhancing the safety.

[0108] It should be understood that the sequence numbers of the steps in the above embodiments do not imply the order of execution. The execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

[0109] An embodiment of the present invention further provides a vehicle driving control system, as Figure 3 shown, including:

[0110] Static load calculation module: used to calculate the static load of each tire of the vehicle according to the longitudinal acceleration, lateral acceleration, road gradient and vehicle body parameters of the vehicle;

[0111] Wheel load calculation module: used to calculate the wheel load of each wheel according to the static load and the longitudinal and lateral load transfer amounts during vehicle driving;

[0112] Load change coefficient calculation module: used to calculate the load change coefficient according to the change amount of the wheel load of each wheel;

[0113] Wheel end torque adjustment module: used to calculate the wheel end target torque of each wheel at the current moment according to the load change coefficient, and control the vehicle drive or brake system according to the wheel end target torque of each wheel at the current moment.

[0114] In some embodiments, the calculation method of the wheel end target torque of each wheel at the current moment includes:

[0115] When the vehicle is driving: T i_Tar = T i_Cur (1 + K i );

[0116] When the vehicle is braking: T i_Tar = T Cur (1 - K i );

[0117] In the formula, T i_Tar represents the wheel end target torque of the i-th wheel at the current moment, T i_cur represents the wheel end torque of the i-th wheel at the previous moment; K i represents the load change coefficient of the i-th wheel.

[0118] Furthermore, in some embodiments, when the vehicle is driving, the calculation method of the wheel end torque of each wheel includes:

[0119] T lf_Tar = T lf_Cur *(1 + K lf ) Formula (32)

[0120] T lr_Tar = T lr_Cur *(1 + K lr) Equation (33)

[0121] T rf_Tar = T rf_Cur *(1 + K rf ) Equation (34)

[0122] T rr_Tar = T rr_Cur *(1 + K rr ) Equation (35)

[0123] When the vehicle is braking, the calculation method of the torque at each wheel end includes:

[0124] T lf_Tar = T lf_Cur *(1 - K lf ) Equation (36)

[0125] T lr_Tar = T lr_Cur *(1 - K lr ) Equation (37)

[0126] T rf_Tar = T rf_Cur *(1 - K rf ) Equation (38)

[0127] T rr_Tar = T rr_Cur *(1 - K rr ) Equation (39)

[0128] Wherein, T lf_Cur , T lr_Cur , T rf_Cur , T rr_Cur are the torques at the left front, left rear, right front, and right rear wheel ends at the previous moment respectively, and T lf_Tar , T lr_Tar , T rf_Tar , T rr_Tar are the target torques at the left front, left rear, right front, and right rear wheel ends at the current moment respectively; K lf , K lr , K rf , K rr are the load change coefficient of the left front, left rear, right front, and right rear tires respectively.

[0129] In some embodiments, the method for calculating the load change coefficient of each wheel includes:

[0130] K i = (wheel load at the current moment - wheel load at the previous moment) / wheel load at the previous moment.

[0131] In some embodiments, when the vehicle is driving, if the adjusted wheel-end torque is negative, the corresponding motor is controlled for electric braking. If it exceeds the minimum torque value of the motor, the corresponding wheel-side braking force is supplemented through control. When the vehicle is braking, the adjusted torque is used to control the braking system. If the adjusted wheel-end torque exceeds the maximum limit of the wheel-side braking system, the corresponding wheel-side drive motor is controlled to supplement through electric braking.

[0132] An embodiment of the present invention further provides a non-transitory computer-readable storage medium. The computer-readable storage medium stores a computer program, and the computer program includes program instructions. When the program instructions are executed by a processor, each step of the method described in the present invention is implemented, which will not be elaborated here.

[0133] The computer-readable storage medium may be the internal storage unit of the data transmission device or computer device provided in any of the foregoing embodiments, such as the hard disk or memory of the computer device. The computer-readable storage medium may also be an external storage device of the computer device, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the computer device.

[0134] Furthermore, the computer-readable storage medium may also include both the internal storage unit and the external storage device of the computer device. The computer-readable storage medium is used to store the computer program and other programs and data required by the computer device. The computer-readable storage medium may also be used to temporarily store the data to be output or already output.

[0135] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0136] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in one or more flows Figure 1 one or more flows and / or blocks Figure 1 or one or more blocks.

[0137] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in one or more flows Figure 1 one or more flows and / or blocks Figure 1 or one or more blocks.

[0138] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more flows Figure 1 one or more flows and / or blocks Figure 1 or one or more blocks.

[0139] Embodiments of the present invention also provide a computer program product, including a computer program / instructions, which implement the steps of the vehicle driving control method when executed by a processor.

[0140] Contents not described in detail in this specification belong to the prior art well-known to those skilled in the art.

Claims

1. A vehicle driving control system, characterized in that, Including: A static load calculation module: used to calculate the static loads of each tire of the vehicle according to the longitudinal acceleration, lateral acceleration, road gradient of the vehicle and the vehicle's own parameters; A wheel load calculation module: used to calculate the wheel loads of each wheel according to the static load during vehicle driving and the load transfer amounts in the longitudinal and lateral directions; A load change coefficient calculation module: used to calculate the load change coefficient according to the change amounts of the wheel loads of each wheel; A wheel end torque adjustment module: used to calculate the target wheel end torque of each wheel at the current moment according to the load change coefficient, and control the vehicle drive or braking system according to the target wheel end torque of each wheel at the current moment.

2. The vehicle driving control system according to claim 1, characterized in that, The method for calculating the load change coefficient of each wheel includes: K i = (Wheel load at the current moment - Wheel load at the previous moment) / Wheel load at the previous moment.

3. The vehicle driving control system according to claim 1, characterized in that, The method for calculating the target wheel end torque of each wheel at the current moment includes: When the vehicle is in drive: T i_Tar = T i_Cur (1 + K i ); where, T i_Tar represents the target wheel-end torque of the i-th wheel at the current moment, and T i_cur represents the wheel-end torque of the i-th wheel before adjustment at the previous moment; K i represents the load change coefficient of the i-th wheel.

4. The vehicle driving control system according to claim 1, characterized in that, The method for calculating the target wheel end torque of each wheel at the current moment includes: When the vehicle is braking: T i_Tar = T Cur (1 - K i ) Where, T i_Tar represents the target wheel-end torque of the i-th wheel at the current moment, and T i_cur represents the wheel-end torque of the i-th wheel before adjustment at the previous moment; K i represents the load change coefficient of the i-th wheel.

5. The vehicle driving control system according to claim 1 or 3, characterized in that, When the vehicle is driving, if the adjusted wheel end torque is negative, control the corresponding motor for electric braking. If it exceeds the minimum torque value of the motor, supplement it by controlling the corresponding wheel side braking force.

6. The vehicle driving control system according to claim 1 or 4, characterized in that, When the vehicle is braking, control the braking system with the adjusted torque. If the adjusted wheel end torque exceeds the maximum limit of the wheel side braking system, supplement it by controlling the corresponding wheel side drive motor for electric braking.

7. The vehicle driving control system according to claim 1, characterized in that, The method for calculating the wheel load of each wheel includes: F lf_t = F lf_s - sgn(a x ) × |w x |- sgn(a y ) × |w y | F lr_t = F lr_s + sgn(a x ) × |w x | - sgn(a y ) × |w y | F rf_t = F rf_s - sgn(a x ) × |w x | + sgn(a y ) × |w y | F rr_t = F rr_s + sgn(a x ) × |w x | + sgn(a y ) × |w y | where F lf_t , F lr_t , F rf_t , F rr_t are the wheel loads of the left front, left rear, right front, and right rear tires respectively; a x is the longitudinal acceleration of the vehicle; a y is the lateral acceleration; w x is the longitudinal load transfer amount; w y is the lateral load transfer amount.

8. A vehicle driving control method, characterized in that, Including: Calculating the static loads of each tire of the vehicle according to the longitudinal acceleration, lateral acceleration, road gradient of the vehicle and the vehicle's own parameters; Calculating the wheel loads of each wheel according to the static load during vehicle driving and the load transfer amounts in the longitudinal and lateral directions; Calculating the load change coefficient according to the change amounts of the wheel loads of each wheel; Calculating the target wheel end torque of each wheel at the current moment according to the load change coefficient, and controlling the vehicle drive or braking system according to the target wheel end torque of each wheel at the current moment.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the vehicle driving control method described in claim 8.

10. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instructions are executed by a processor, it implements the steps of the vehicle driving control method described in claim 8.

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