Braking force distribution method, device, equipment, medium and vehicle

Abstract

The invention discloses a braking force distribution method, device and equipment, a medium and a vehicle, and relates to the technical field of vehicles. The braking force distribution method comprises the steps of obtaining target data; predicting a longitudinal acceleration and a lateral acceleration of the vehicle based on the target data; the target braking force currently needed by the vehicle is calculated through the longitudinal acceleration and the transverse acceleration; according to the friction braking capacity of each wheel, the current actual friction braking force of each wheel and the current actual recovery braking capacity of a front axle and a rear axle of the vehicle, the maximum recovery capacity capable of being provided by an actuator, a front axle motor and a rear axle motor corresponding to each wheel is calculated; and performing braking force distribution on each wheel, a vehicle front axle and a vehicle rear axle based on the target braking force and the maximum recovery capacity which can be provided by the actuator corresponding to each wheel, the front axle motor and the rear axle motor. Through the scheme disclosed by the invention, the NVH interference can be avoided while the requirement of vehicle stability can be met.

Description

Technical Field

[0001] The present application belongs to the field of vehicle technology, and in particular relates to a braking force distribution method, device, equipment, medium and vehicle. Background Art

[0002] Vehicle braking refers to applying a certain braking force to certain parts of the vehicle (mainly the wheels), thereby forcing it to brake to a certain extent, so that the moving vehicle can be forced to slow down or even stop according to the driver's requirements, so that a stopped car can be stably parked under various road conditions (including on ramps), and the speed of a vehicle traveling downhill can be kept stable, etc.

[0003] In the related technology, braking force distribution is mainly carried out through hydraulic braking system. The hydraulic braking system realizes the distribution of braking force by controlling the opening and closing of the hydraulic unit and solenoid valve of the braking system. The braking force of the hydraulic braking system is generated by the master brake cylinder and transmitted to each wheel through the brake pipeline. When the hydraulic braking system controls the braking force, the solenoid valve corresponding to the wheel without pressure request also needs to be controlled, and there is a certain mutual influence and additional noise, vibration, harshness (NVH) interference. Summary of the invention

[0004] The embodiments of the present application provide a braking force distribution method, device, equipment, medium and vehicle, which can solve the problem of NVH interference.

[0005] In a first aspect, an embodiment of the present application provides a braking force distribution method, comprising:

[0006] Acquiring target data, wherein the target data includes a driver's current desired braking force, a vehicle's current actual braking force, a vehicle's current acceleration, a vehicle's current actual front axle regenerative braking capability, a vehicle's current actual rear axle regenerative braking capability, a driver's current desired yaw rate, and a vehicle's current yaw rate;

[0007] Based on the target data, predict the longitudinal acceleration and lateral acceleration of the vehicle;

[0008] Calculate the target braking force currently required by the vehicle using the longitudinal acceleration and lateral acceleration;

[0009] According to the friction braking capacity of each wheel, the actual friction braking force of each wheel, the actual recovery braking capacity of the current front axle of the vehicle, and the actual recovery braking capacity of the current rear axle of the vehicle, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor are calculated;

[0010] Braking force is distributed to each wheel, the front axle of the vehicle and the rear axle of the vehicle based on the target braking force, the maximum braking capacity that the actuator corresponding to each wheel can provide, the maximum recovery capacity that the front axle motor can provide and the maximum recovery capacity that the rear axle motor can provide.

[0011] In a second aspect, an embodiment of the present application provides a braking force distribution device, comprising:

[0012] an acquisition module, used to acquire target data, wherein the target data includes the driver's current expected braking force, the vehicle's current actual braking force, the vehicle's current acceleration, the vehicle's current front axle actual recovery braking capacity, the vehicle's current rear axle actual recovery braking capacity, the driver's current expected yaw rate, and the vehicle's current yaw rate;

[0013] A prediction module, used for predicting the longitudinal acceleration and lateral acceleration of the vehicle based on the target data;

[0014] A first calculation module, used to calculate the target braking force currently required by the vehicle using the longitudinal acceleration and the lateral acceleration;

[0015] The second calculation module is used to calculate the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor according to the friction braking capacity of each wheel, the current actual friction braking force of each wheel, the current actual recovery braking capacity of the front axle of the vehicle, and the current actual recovery braking capacity of the rear axle of the vehicle;

[0016] A distribution module is used to distribute braking force to each wheel, a front axle of the vehicle and a rear axle of the vehicle based on a target braking force, a maximum braking capacity that can be provided by an actuator corresponding to each wheel, a maximum recovery capacity that can be provided by a front axle motor and a maximum recovery capacity that can be provided by a rear axle motor.

[0017] In a third aspect, an embodiment of the present application provides an electronic device, comprising: a processor and a memory storing computer program instructions; when the processor reads and executes the computer program instructions, the braking force distribution method provided in the first aspect of the embodiment of the present application is implemented.

[0018] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having computer program instructions stored thereon. When the computer program instructions are executed by a processor, the braking force distribution method provided in the first aspect of the embodiment of the present application is implemented.

[0019] In a fifth aspect, an embodiment of the present application provides a computer program product. When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes the braking force distribution method provided in the first aspect of the embodiment of the present application.

[0020] In a sixth aspect, an embodiment of the present application provides a vehicle, comprising at least one of the following items:

[0021] The braking force distribution device provided by the second aspect of the embodiment of the present application;

[0022] The electronic device provided by the third aspect of the embodiment of the present application;

[0023] A fourth aspect of an embodiment of the present application provides a computer-readable storage medium.

[0024] In the embodiment of the present application, target data including the driver's current expected braking force, the vehicle's current actual braking force, the vehicle's current acceleration, the vehicle's current actual front axle recovery braking capacity, the vehicle's current rear axle actual recovery braking capacity, the driver's current expected yaw rate, and the vehicle's current yaw rate are obtained; based on the target data, the longitudinal acceleration and lateral acceleration of the vehicle are predicted; the target braking force currently required for the vehicle is calculated using the longitudinal acceleration and lateral acceleration; the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor are calculated based on the friction braking capacity of each wheel, the current actual friction braking force of each wheel, the vehicle's current front axle actual recovery braking capacity, and the vehicle's current rear axle actual recovery braking capacity; based on the target braking force, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor, the braking force is distributed to each wheel, the front axle of the vehicle, and the rear axle of the vehicle. Compared with the related art, the solution disclosed in the present application allocates different braking forces to each wheel by combining the current actual braking force of the vehicle when the driver's current expected braking force is obtained, thereby avoiding NVH interference while meeting the requirements of vehicle stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0026] Figure 1 is a flow chart of a braking force distribution method provided in an embodiment of the present application;

[0027] Figure 2 is a structural schematic diagram of a braking force distribution device provided in an embodiment of the present application;

[0028] Figure 3 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0029] To more clearly understand the above objects, features, and advantages of the present application, the solutions of the present application will be further described below. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments may be combined with each other.

[0030] Many specific details are set forth in the following description to facilitate a full understanding of the present application, but the present application may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the present application, rather than all embodiments.

[0031] The braking force distribution method, device, equipment, medium, and vehicle provided by the embodiments of the present application will be described in detail below with reference to the accompanying drawings, through specific embodiments and their application scenarios.

[0032] Figure 1 is a schematic flowchart of the braking force distribution method provided by the embodiments of the present application. As Figure 1 shown, the braking force distribution method may include:

[0033] Step 101: Obtain target data;

[0034] In some possible implementations of the embodiments of the present application, the target data includes the driver's current desired braking force, the vehicle's current actual braking force, the vehicle's current acceleration, the vehicle's current actual regenerative braking capacity of the front axle, the vehicle's current actual regenerative braking capacity of the rear axle, the driver's current desired yaw rate, and the vehicle's current yaw rate;

[0035] Step 102: Predict the longitudinal acceleration and lateral acceleration of the vehicle based on the target data;

[0036] In some possible implementations of the embodiments of the present application, in step 102, when predicting the longitudinal acceleration of the vehicle based on the target data, the longitudinal acceleration of the vehicle may be calculated according to the following formula (1):

[0037]

[0038] where, in formula (1), Veh_AxEst is the longitudinal acceleration of the vehicle, IMU_Ax is the longitudinal component of the vehicle's current acceleration, Drv_BrkFxTar is the driver's current desired braking force, Veh_BrkFxAct is the vehicle's current actual braking force, BFD_FaRegenFxAct is the vehicle's current actual regenerative braking capacity of the front axle, BFD_RaRegenFxAct is the vehicle's current actual regenerative braking capacity of the rear axle, and m is the mass of the vehicle.

[0039] In some possible implementations of the embodiment of the present application, in step 102, when predicting the lateral acceleration of the vehicle based on the target data, the lateral acceleration of the vehicle may be calculated according to the following formula (2):

[0040] Veh_AyEst=IMU_Ay+(Drv_TarYawRate-IMU_YawRate)*Veh_Vx (2)

[0041] Wherein, in formula (2), Veh_AyEst is the lateral acceleration of the vehicle, IMU_Ay is the lateral component of the current acceleration of the vehicle, Drv_TarYawRate is the driver's current desired yaw rate, IMU_YawRate is the current yaw rate of the vehicle, and Veh_Vx is the longitudinal component of the vehicle velocity.

[0042] Step 103: Calculate the target braking force currently required by the vehicle using the longitudinal acceleration and the lateral acceleration;

[0043] In some possible implementations of the embodiments of the present application, in step 103, after the longitudinal acceleration and lateral acceleration of the vehicle are predicted, the overall acceleration of the vehicle can be calculated based on the predicted longitudinal acceleration and lateral acceleration, and then the target braking force currently required for the vehicle can be calculated based on the physical relationship between force and acceleration.

[0044] Step 104: Calculate the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor according to the friction braking capacity of each wheel, the current actual friction braking force of each wheel, the current actual recovery braking capacity of the front axle of the vehicle, and the current actual recovery braking capacity of the rear axle of the vehicle;

[0045] The embodiments of the present application do not elaborate on the process of calculating the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor based on the friction braking capacity of each wheel, the current actual friction braking force of each wheel, the current actual recovery braking capacity of the front axle of the vehicle, and the current actual recovery braking capacity of the rear axle of the vehicle. The specific process can refer to the process in the relevant technology that calculates the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor based on the friction braking capacity of each wheel, the current actual friction braking force of each wheel, the current actual recovery braking capacity of the front axle of the vehicle, and the current actual recovery braking capacity of the rear axle of the vehicle.

[0046] Step 105: Based on the target braking force, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor and the maximum recovery capacity that can be provided by the rear axle motor, the braking force is distributed to each wheel, the front axle of the vehicle and the rear axle of the vehicle.

[0047] In some possible implementations of the embodiments of the present application, in step 105, the maximum braking capacity of the front axle can be calculated based on the maximum recovery capacity that can be provided by the front axle motor, the left front wheel friction braking capacity and the right front wheel friction braking capacity, wherein the maximum braking capacity of the front axle is equal to the sum of the maximum recovery capacity that can be provided by the front axle motor, the left front wheel friction braking capacity and the right front wheel friction braking capacity; the maximum braking capacity of the rear axle can be calculated based on the maximum recovery capacity that can be provided by the rear axle motor, the left rear wheel friction braking capacity and the right rear wheel friction braking capacity, wherein the maximum braking capacity of the rear axle is equal to the sum of the maximum recovery capacity that can be provided by the rear axle motor, the left rear wheel friction braking capacity and the right rear wheel friction braking capacity.

[0048] When distributing braking force to each wheel, the front axle of the vehicle and the rear axle of the vehicle, the braking force allocated to the front axle of the vehicle is not greater than the maximum braking capacity of the front axle, the braking force allocated to the rear axle of the vehicle is not greater than the maximum braking capacity of the rear axle, the sum of the braking force allocated to the front axle of the vehicle and the braking force allocated to the rear axle of the vehicle is equal to the target braking force, the sum of the braking forces allocated to each front wheel of the vehicle is equal to the braking force allocated to the front axle of the vehicle, and the sum of the braking forces allocated to each rear wheel of the vehicle is equal to the braking force allocated to the rear axle of the vehicle.

[0049] In the embodiment of the present application, target data including the driver's current expected braking force, the vehicle's current actual braking force, the vehicle's current acceleration, the vehicle's current actual front axle recovery braking capacity, the vehicle's current rear axle actual recovery braking capacity, the driver's current expected yaw rate, and the vehicle's current yaw rate are obtained; based on the target data, the longitudinal acceleration and lateral acceleration of the vehicle are predicted; the target braking force currently required for the vehicle is calculated using the longitudinal acceleration and lateral acceleration; the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor are calculated based on the friction braking capacity of each wheel, the current actual friction braking force of each wheel, the vehicle's current front axle actual recovery braking capacity, and the vehicle's current rear axle actual recovery braking capacity; based on the target braking force, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor, the braking force is distributed to each wheel, the front axle of the vehicle, and the rear axle of the vehicle. Compared with the related art, the solution disclosed in the present application allocates different braking forces to each wheel by combining the current actual braking force of the vehicle when the driver's current expected braking force is obtained, thereby avoiding NVH interference while meeting the requirements of vehicle stability.

[0050] In some possible implementations of the embodiment of the present application, before step 103, the braking force distribution method provided by the embodiment of the present application may further include: adjusting the longitudinal acceleration according to the front axle slip rate and the rear axle slip rate.

[0051] In an embodiment of the present application, after adjusting the longitudinal acceleration, the target braking force required for the vehicle can be recalculated based on the adjusted longitudinal acceleration, and the braking force can be distributed to each wheel, the front axle of the vehicle, and the rear axle of the vehicle based on the recalculated target braking force required for the vehicle.

[0052] In some possible implementations of the embodiments of the present application, when the longitudinal acceleration is adjusted according to the front axle slip rate and the rear axle slip rate, the longitudinal acceleration can be reduced when the front axle slip rate is greater than the rear axle slip rate; and the longitudinal acceleration can be increased when the front axle slip rate is less than the rear axle slip rate.

[0053] In the embodiment of the present application, when the front axle slip rate is greater than the rear axle slip rate, the vertical load of the rear axle is increased by reducing the longitudinal acceleration; according to vehicle dynamics theory, on a uniform road surface, the braking force or driving force that each wheel can withstand is in a certain linear relationship with the vertical force of the tire, that is, the greater the vertical force the tire withstands, the greater the driving force, braking force, and lateral force it can withstand. When the vertical load of the rear axle increases, the braking force of the rear axle increases, achieving the purpose of transferring the braking force to the rear axle, which can alleviate the excessive slip rate of the front axle. When the rear axle slip rate is greater than the front axle slip rate, the vertical load of the front axle is increased by increasing the longitudinal acceleration. When the vertical load of the front axle increases, the braking force of the front axle increases, achieving the purpose of transferring the braking force to the front axle, which can alleviate the excessive slip rate of the rear axle.

[0054] In some possible implementations of the embodiments of the present application, before step 103, the braking force distribution method provided by the embodiments of the present application may also include: adjusting the lateral acceleration according to the steering state of the vehicle, wherein the steering state includes an oversteering state or an understeering state.

[0055] In an embodiment of the present application, after adjusting the lateral acceleration, the target braking force required for the vehicle can be recalculated based on the adjusted lateral acceleration, and the braking force can be distributed to each wheel, the front axle of the vehicle, and the rear axle of the vehicle based on the recalculated target braking force required for the vehicle.

[0056] In some possible implementations of the embodiments of the present application, when adjusting the longitudinal acceleration according to the steering state of the vehicle, the lateral acceleration can be increased when the vehicle is in an oversteering state and the lateral acceleration is greater than zero; the lateral acceleration can be decreased when the vehicle is in an oversteering state and the lateral acceleration is less than zero; the lateral acceleration can be decreased when the vehicle is in an understeering state and the lateral acceleration is greater than zero; and the lateral acceleration can be increased when the vehicle is in an understeering state and the lateral acceleration is greater than zero.

[0057] In some possible implementations of the embodiments of the present application, there are two cases of vehicle steering: left turn and right turn. Let the left direction of the vehicle be positive and the right direction of the vehicle be negative.

[0058] In the embodiments of the present application, when the vehicle is in an oversteering state during a left turn, by increasing the virtual lateral acceleration of the front axle, that is, increasing the absolute value of the virtual lateral acceleration, the oversteering during the left turn of the vehicle can be suppressed; when the vehicle is in an oversteering state during a right turn, by decreasing the virtual lateral acceleration of the front axle, that is, increasing the absolute value of the virtual lateral acceleration, the oversteering during the right turn of the vehicle can be suppressed. When the vehicle is in an understeering state during a left turn, by decreasing the virtual lateral acceleration of the rear axle, that is, decreasing the absolute value of the virtual lateral acceleration, the understeering during the left turn of the vehicle can be suppressed; when the vehicle is in an understeering state during a right turn, by increasing the virtual lateral acceleration of the rear axle, that is, decreasing the absolute value of the virtual lateral acceleration, the understeering during the right turn of the vehicle can be suppressed.

[0059] In some possible implementations of the embodiments of the present application, when the direction of the driver's desired yaw rate DrvYawRtTar is the same as the direction of the actual yaw rate of the vehicle VehYawRtAct, the absolute value of the driver's desired yaw rate DrvYawRtTar is greater than the yaw rate threshold P_StrghtDrvYawRt, the absolute value of the actual yaw rate of the vehicle VehYawRtAct is greater than the absolute value of the driver's desired yaw rate DrvYawRtTar, and the absolute value of the vehicle lateral acceleration VehLatAyAct is greater than the lateral acceleration threshold P_AyUpThd, that is, DrvYawRtTar * VehYawRtAct > 0, abs(DrvYawRtTar) > P_StrghtDrvYawRt, abs(VehYawRtAct) > abs(DrvYawRtTar), abs(VehLatAyAct) > P_AyUpThd, the vehicle is in an oversteering state.

[0060] In some possible implementations of the embodiments of the present application, when the driver's desired yaw rate DrvYawRtTar is in the same direction as the vehicle's actual yaw rate VehYawRtAct, the absolute value of the driver's desired yaw rate DrvYawRtTar is greater than the yaw rate threshold value P_StrghtDrvYawRt, and the absolute value of the driver's desired yaw rate DrvYawRtTar is greater than the absolute value of the vehicle's actual yaw rate VehYawRtAct, the vehicle lateral When the absolute value of the acceleration VehLatAyAct is greater than the lateral acceleration threshold value P_AyUpThd, that is, DrvYawRtTar*VehYawRtAct>0, abs(DrvYawRtTar)>P_StrghtDrvYawRt, abs(DrvYawRtTar)>abs(VehYawRtAct), abs(VehLatAyAct)>P_AyUpThd, the vehicle is in an understeering state.

[0061] In some possible implementations of the embodiments of the present application, before step 105, the braking force distribution method provided by the embodiments of the present application may also include: calculating the incremental braking capacity based on the driver's current expected braking force, the driver's expected braking force in the previous cycle, and the braking force deviation in the previous cycle.

[0062] Accordingly, step 105 may include allocating the incremental braking capacity based on the target braking force, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, the maximum recovery capacity that can be provided by the rear axle motor and the braking force allocated in the previous cycle.

[0063] In some possible implementations of the embodiments of the present application, when calculating the incremental braking capacity based on the driver's current expected braking force, the driver's expected braking force in the previous cycle, and the braking force deviation in the previous cycle, the incremental braking capacity may be calculated according to the following formula (3):

[0064] ΔBrkFxTar=ΔDrvBrkReq+ΔBrkFxAct (3)

[0065] Wherein, in formula (3), ΔBrkFxTar is the incremental braking capacity, ΔDrvBrkReq is the driver's expected braking force increment, ΔBrkFxAct is the braking force deviation existing in the previous cycle, and ΔDrvBrkReq is the difference between the driver's current expected braking force and the driver's expected braking force in the previous cycle.

[0066] In some possible implementations of the embodiments of the present application, when allocating the incremental braking capacity, the incremental braking capacity may be allocated to the front axle and the rear axle based on the allocation ratio and the incremental upper and lower limits of the axle ends.

[0067] If the incremental braking capacity ensures that the braking force distributed on the front and rear axles uses up all the energy recovery or the braking force on the front and rear axles reaches the optimal slip ratio, and there is still excess braking force, it will continue to be distributed according to the front and rear axle braking force distribution ratio to ensure that the currently requested braking force is distributed to the front and rear axles;

[0068] If the incremental braking capacity still has excess braking force while ensuring that the braking forces on the front and rear axles use up all the braking capacities on the front and rear axles, it will continue to be distributed according to the front and rear axle braking force distribution ratio to ensure that the currently requested braking force is distributed to the front and rear axles.

[0069] When the driver's braking force demand is increasing or remains unchanged, it is determined whether the current driver's incremental braking force demand exceeds the front axle and rear axle incremental upper limits.

[0070] The first case: If the incremental braking force demands of the front and rear axles do not exceed the corresponding incremental upper limits, the incremental braking force demands of the front and rear axles are directly allocated, that is, the front axle incremental braking force is allocated according to the front axle incremental braking force demand, and the rear axle incremental braking force is allocated according to the rear axle braking force demand.

[0071] The second situation: If the incremental demand for front axle braking force does not exceed the front axle incremental upper limit, the incremental demand for rear axle braking force exceeds the rear axle incremental upper limit, and the excess braking force demand of the rear axle can be met by the remaining braking force of the front axle, then the front axle incremental braking force is distributed according to the sum of the front axle incremental braking force demand and the excess braking force demand of the rear axle; the rear axle incremental braking force is distributed according to the rear axle braking force incremental upper limit.

[0072] The third situation: If the incremental braking force demand of the front axle does not exceed the incremental upper limit of the front axle, the incremental braking force demand of the rear axle exceeds the incremental upper limit of the rear axle, and the excess braking force demand of the rear axle cannot be met by the remaining braking force of the front axle, then the front axle incremental braking force is first allocated according to the front axle incremental braking force demand, and the rear axle incremental braking force is first allocated according to the incremental upper limit of the rear axle braking force, and then, the excess incremental braking force demand of the rear axle is allocated to the front axle and rear axle according to the allocation ratio of the front axle and the rear axle.

[0073] The fourth case: If the incremental demand for the rear axle braking force does not exceed the upper limit of the rear axle incremental value, the incremental demand for the front axle braking force exceeds the upper limit of the front axle incremental value, and the excess braking force demand of the front axle can be met by the remaining braking force of the rear axle, then the front axle incremental braking force is allocated according to the upper limit of the front axle braking force increment; the rear axle incremental braking force is allocated according to the sum of the rear axle incremental braking demand and the excess braking force demand of the front axle.

[0074] The fifth case: If the incremental braking force demand of the rear axle does not exceed the upper limit of the rear axle incremental value, the incremental braking force demand of the front axle exceeds the upper limit of the front axle incremental value, and the excess braking force demand of the front axle cannot be met by the remaining braking force of the rear axle, then the rear axle incremental braking force is first allocated according to the rear axle incremental braking force demand, and the front axle incremental braking force is first allocated according to the upper limit of the rear axle braking force increment, and then, the excess incremental braking force demand of the front axle is allocated to the front axle and rear axle according to their allocation ratio.

[0075] The sixth case: If the incremental braking force demands of both the front and rear axles exceed the corresponding incremental upper limits, the front axle incremental braking force will be first allocated according to the front axle braking force incremental upper limit, and the rear axle incremental braking force will be first allocated according to the rear axle braking force incremental upper limit, and then the excess incremental braking force demands of the front and rear axles will be allocated according to the allocation ratio of the front and rear axles.

[0076] In the embodiment of the present application, by allocating the incremental braking capacity, it is possible to avoid the situation where inaccurate braking force distribution is caused by directly allocating the braking force demand because part of the braking force has been allocated in the previous cycle.

[0077] Corresponding to the above method embodiment, the present application embodiment also provides a braking force distribution device. Figure 2 As shown, Figure 2 200 is a schematic diagram of the structure of the braking force distribution device provided in an embodiment of the present application. The braking force distribution device 200 may include:

[0078] An acquisition module 201 is used to acquire target data, wherein the target data includes the driver's current expected braking force, the vehicle's current actual braking force, the vehicle's current acceleration, the vehicle's current front axle actual recovery braking capacity, the vehicle's current rear axle actual recovery braking capacity, the driver's current expected yaw rate, and the vehicle's current yaw rate;

[0079] A prediction module 202, for predicting the longitudinal acceleration and lateral acceleration of the vehicle based on the target data;

[0080] A first calculation module 203 is used to calculate the target braking force currently required by the vehicle using the longitudinal acceleration and the lateral acceleration;

[0081] The second calculation module 204 is used to calculate the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor according to the friction braking capacity of each wheel, the current actual friction braking force of each wheel, the current actual recovery braking capacity of the front axle of the vehicle, and the current actual recovery braking capacity of the rear axle of the vehicle;

[0082] The allocation module 205 is used to allocate braking force to each wheel, the front axle of the vehicle and the rear axle of the vehicle based on the target braking force, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor and the maximum recovery capacity that can be provided by the rear axle motor.

[0083] In the embodiment of the present application, target data including the driver's current expected braking force, the vehicle's current actual braking force, the vehicle's current acceleration, the vehicle's current actual front axle recovery braking capacity, the vehicle's current rear axle actual recovery braking capacity, the driver's current expected yaw rate, and the vehicle's current yaw rate are obtained; based on the target data, the longitudinal acceleration and lateral acceleration of the vehicle are predicted; the target braking force currently required for the vehicle is calculated using the longitudinal acceleration and lateral acceleration; the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor are calculated based on the friction braking capacity of each wheel, the current actual friction braking force of each wheel, the vehicle's current front axle actual recovery braking capacity, and the vehicle's current rear axle actual recovery braking capacity; based on the target braking force, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor, the braking force is distributed to each wheel, the front axle of the vehicle, and the rear axle of the vehicle. Compared with the related art, the solution disclosed in the present application allocates different braking forces to each wheel by combining the current actual braking force of the vehicle when the driver's current expected braking force is obtained, thereby avoiding NVH interference while meeting the requirements of vehicle stability.

[0084] In some possible implementations of the embodiments of the present application, the prediction module 202 may be specifically used for:

[0085] The longitudinal acceleration and lateral acceleration of the vehicle are calculated according to the above formulas (1) and (2).

[0086] In some possible implementations of the embodiments of the present application, the braking force distribution device provided in the embodiments of the present application may further include:

[0087] The first adjustment module is used to adjust the longitudinal acceleration according to the front axle slip rate and the rear axle slip rate.

[0088] In some possible implementations of the embodiments of the present application, the first adjustment module may be specifically used to:

[0089] When the front axle slip rate is greater than the rear axle slip rate, the longitudinal acceleration is reduced;

[0090] When the front axle slip rate is less than the rear axle slip rate, the longitudinal acceleration is increased.

[0091] In some possible implementations of the embodiments of the present application, the braking force distribution device provided in the embodiments of the present application may further include:

[0092] The second adjustment module is used to adjust the lateral acceleration according to the steering state of the vehicle, wherein the steering state includes an oversteering state or an understeering state.

[0093] In some possible implementations of the embodiments of the present application, the second adjustment module may be specifically used to:

[0094] When the vehicle is in an oversteering state and the lateral acceleration is greater than zero, the lateral acceleration is increased;

[0095] When the vehicle is in an oversteering state and the lateral acceleration is less than zero, reducing the lateral acceleration;

[0096] When the vehicle is in an understeering state and the lateral acceleration is greater than zero, reducing the lateral acceleration;

[0097] When the vehicle is in an understeer state and the lateral acceleration is greater than zero, the lateral acceleration is increased.

[0098] In some possible implementations of the embodiments of the present application, the braking force distribution device provided in the embodiments of the present application may further include:

[0099] A third calculation module, for calculating the incremental braking capacity based on the driver's current expected braking force, the driver's expected braking force in the previous cycle, and the braking force deviation existing in the previous cycle;

[0100] Accordingly, the allocation module 205 may be specifically used for:

[0101] The incremental braking capacity is allocated based on the target braking force, the maximum braking capacity that the actuator corresponding to each wheel can provide, the maximum recovery capacity that the front axle motor can provide, the maximum recovery capacity that the rear axle motor can provide, and the braking force allocated in the previous cycle.

[0102] Figure 3 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

[0103] The electronic device may include a processor 301 and a memory 302 storing computer program instructions.

[0104] Specifically, the processor 301 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0105] The memory 302 may include a large capacity memory for data or instructions. By way of example and not limitation, the memory 302 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. Where appropriate, the memory 302 may include a removable or non-removable (or fixed) medium. Where appropriate, the memory 302 may be inside or outside the electronic device. In some specific embodiments, the memory 302 is a non-volatile solid-state memory.

[0106] In some specific embodiments, the memory may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk storage medium device, an optical storage medium device, a flash memory device, an electrical, optical or other physical / tangible memory storage device. Therefore, generally, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., a memory device) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the braking force distribution method according to the present application.

[0107] The processor 301 implements the braking force distribution method provided in the embodiment of the present application by reading and executing the computer program instructions stored in the memory 302 .

[0108] In some examples, the electronic device may further include a communication interface 303 and a bus 310. Figure 3 As shown, the processor 301, the memory 302, and the communication interface 303 are connected via a bus 310 and communicate with each other.

[0109] The communication interface 303 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0110] The bus 310 includes hardware, software or both, coupling the components of the electronic device to each other. For example, but not limitation, the bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Extended Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a Hyper Transport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an InfiniBand interconnect, a Low Pin Count (LPC) bus, a memory bus, a Micro channel architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local Bus (VLB) bus or other suitable buses or a combination of two or more of these. Where appropriate, the bus 310 may include one or more buses. Although embodiments of the present application describe and illustrate a particular bus, the present application contemplates any suitable bus or interconnect.

[0111] The electronic device can execute the braking force distribution method provided in the embodiment of the present application, thereby achieving the corresponding technical effects of the braking force distribution method provided in the embodiment of the present application.

[0112] In addition, in combination with the braking force distribution method in the above embodiment, the embodiment of the present application also provides a computer-readable storage medium for implementation. The computer-readable storage medium stores computer program instructions; when the computer program instructions are executed by the processor, the braking force distribution method provided in the embodiment of the present application is implemented. Examples of computer-readable storage media include non-transitory computer-readable media, such as ROM, RAM, magnetic disk or optical disk, etc.

[0113] An embodiment of the present application also provides a computer program product. When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes the braking force distribution method provided in the embodiment of the present application and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0114] The present application also provides a vehicle, comprising at least one of the following items:

[0115] The braking force distribution device provided in the embodiment of the present application;

[0116] The electronic device provided by the embodiment of the present application;

[0117] The computer-readable storage medium provided in the embodiment of the present application

[0118] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

Claims

1. A braking force distribution method, It is characterized in that The method comprises: Acquiring target data, wherein the target data includes a driver's current desired braking force, a vehicle's current actual braking force, a vehicle's current acceleration, a vehicle's current front axle actual regenerative braking capability, a vehicle's current rear axle actual regenerative braking capability, a driver's current desired yaw rate, and a vehicle's current yaw rate; predicting the longitudinal acceleration and the lateral acceleration of the vehicle based on the target data; Calculating a target braking force currently required for the vehicle using the longitudinal acceleration and the lateral acceleration; Calculate the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor according to the friction braking capacity of each wheel, the current actual friction braking force of each wheel, the current actual recovery braking capacity of the front axle of the vehicle, and the current actual recovery braking capacity of the rear axle of the vehicle; Based on the target braking force, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor and the maximum recovery capacity that can be provided by the rear axle motor, the braking force is distributed to each wheel, the front axle of the vehicle and the rear axle of the vehicle.

2. The method according to claim 1, It is characterized in that Predicting the longitudinal acceleration of the vehicle based on the target data includes: The longitudinal acceleration of the vehicle is calculated according to the following formula: Among them, Veh_AxEst is the longitudinal acceleration of the vehicle, IMU_Ax is the longitudinal component of the current acceleration of the vehicle, Drv_BrkFxTar is the driver's current desired braking force, Veh_BrkFxAct is the vehicle's current actual braking force, BFD_FaRegenFxAct is the vehicle's current actual front axle recovery braking capability, BFD_RaRegenFxAct is the vehicle's current actual rear axle recovery braking capability, and m is the vehicle's mass.

3. The method according to claim 1, It is characterized in that Predicting the lateral acceleration of the vehicle based on the target data includes: The lateral acceleration of the vehicle is calculated according to the following formula: Veh_AyEst=IMU_Ay+(Drv_TarYawRate-IMU_YawRate)*Veh_Vx Among them, Veh_AyEst is the lateral acceleration of the vehicle, IMU_Ay is the lateral component of the current acceleration of the vehicle, Drv_TarYawRate is the driver's current expected yaw rate, IMU_YawRate is the current yaw rate of the vehicle, and Veh_Vx is the longitudinal component of the vehicle speed.

4. The method according to claim 1, It is characterized in that Before calculating the target braking force currently required for the vehicle by using the longitudinal acceleration and the lateral acceleration, the method further includes: The longitudinal acceleration is adjusted according to the front axle slip rate and the rear axle slip rate.

5. The method according to claim 4, It is characterized in that The adjusting the longitudinal acceleration according to the front axle slip rate and the rear axle slip rate includes: When the front axle slip rate is greater than the rear axle slip rate, reducing the longitudinal acceleration; When the front axle slip ratio is smaller than the rear axle slip ratio, the longitudinal acceleration is increased.

6. The method according to claim 1, It is characterized in that Before calculating the target braking force currently required for the vehicle by using the longitudinal acceleration and the lateral acceleration, the method further includes: The lateral acceleration is adjusted according to a steering state of the vehicle, wherein the steering state includes an oversteering state or an understeering state.

7. The method according to claim 6, It is characterized in that The adjusting the lateral acceleration according to the steering state of the vehicle includes: When the vehicle is in the oversteering state and the lateral acceleration is greater than zero, increasing the lateral acceleration; When the vehicle is in the oversteering state and the lateral acceleration is less than zero, reducing the lateral acceleration; When the vehicle is in the understeering state and the lateral acceleration is greater than zero, reducing the lateral acceleration; When the vehicle is in the understeering state and the lateral acceleration is greater than zero, the lateral acceleration is increased.

8. The method according to claim 1, It is characterized in that Before distributing the braking force to each wheel, the front axle of the vehicle, and the rear axle of the vehicle based on the target braking force, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor, the method further includes: Calculating incremental braking capacity based on the driver's current expected braking force, the driver's expected braking force in the previous cycle, and the braking force deviation in the previous cycle; The method of distributing the braking force to each wheel, the front axle of the vehicle, and the rear axle of the vehicle based on the target braking force, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor includes: The incremental braking capacity is allocated based on the target braking force, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, the maximum recovery capacity that can be provided by the rear axle motor and the braking force allocated in the previous cycle.

9. A braking force distribution device, It is characterized in that The device comprises: an acquisition module, used for acquiring target data, wherein the target data includes a driver's current desired braking force, a vehicle's current actual braking force, a vehicle's current acceleration, a vehicle's current actual front axle recovery braking capability, a vehicle's current actual rear axle recovery braking capability, a driver's current desired yaw rate, and a vehicle's current yaw rate; A prediction module, configured to predict the longitudinal acceleration and the lateral acceleration of the vehicle based on the target data; A first calculation module, configured to calculate a target braking force currently required by the vehicle using the longitudinal acceleration and the lateral acceleration; a second calculation module, for calculating the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor, and the maximum recovery capacity that can be provided by the rear axle motor according to the friction braking capacity of each wheel, the current actual friction braking force of each wheel, the current actual recovery braking capacity of the front axle of the vehicle, and the current actual recovery braking capacity of the rear axle of the vehicle; A distribution module is used to distribute the braking force to each wheel, the front axle of the vehicle and the rear axle of the vehicle based on the target braking force, the maximum braking capacity that can be provided by the actuator corresponding to each wheel, the maximum recovery capacity that can be provided by the front axle motor and the maximum recovery capacity that can be provided by the rear axle motor.

10. An electronic device, It is characterized in that The electronic device comprises: a processor and a memory storing computer program instructions; The processor reads and executes the computer program instructions to implement the braking force distribution method as described in any one of claims 1-8.

11. A computer-readable storage medium, It is characterized in that The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by a processor, the braking force distribution method according to any one of claims 1 to 8 is implemented.

12. A vehicle, It is characterized in that The vehicle includes at least one of the following: The braking force distribution device according to claim 9; The electronic device according to claim 10; The computer readable storage medium of claim 11.

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