Method, device and system for adjusting damping coefficient of suspension and storage medium

Abstract

The invention discloses a suspension damping coefficient adjusting method, device and system and a storage medium, and the method comprises the steps that when a vehicle is in a braking state, preset parameters of the vehicle are obtained, and the preset parameters at least comprise the longitudinal acceleration of the vehicle and the wheel speed of each wheel; judging whether the vehicle is braked at a curve or not according to preset parameters of the vehicle; when the vehicle is braked at the curve, calculating a longitudinal load transfer influence factor and a transverse load transfer influence factor of the vehicle; determining a target braking force of each wheel according to the longitudinal load transfer influence factor and the transverse load transfer influence factor of the vehicle; and the target damping coefficient of the corresponding suspension is adjusted according to the target braking force of each wheel. According to the scheme, the probability of sideslip and drifting of the vehicle caused by tire load transfer during curve braking is reduced, and the stability of the vehicle during braking is improved.

Description

Technical Field

[0001] This application relates to the field of emergency braking coordination control technology, and in particular to a method, device, system and storage medium for adjusting the suspension damping coefficient. Background Technology

[0002] The suspension system is an elastic device in a car that connects the chassis and wheels. It consists of elastic elements, guiding mechanisms, shock absorbers, and other components, and is mainly used to buffer road impacts and improve ride comfort. Variable damping suspension adjustment collects data such as vehicle acceleration, wheel displacement, and steering angle in real time, calculates the acceleration distributed to each wheel based on a set algorithm, and adjusts the damping coefficient of the suspension in real time by adjusting the flow resistance of the oil inside the shock absorber.

[0003] Under emergency braking conditions, the vehicle's braking force increases abruptly, easily causing the vehicle body to pitch. Current technology does not consider the tire load transfer caused by vehicle pitch, especially during cornering, where the vehicle's lateral traction decreases, making it prone to skidding and fishtailing due to the inability to maintain stability. Furthermore, the suspension system reduces front suspension damping for comfort, further resulting in insufficient tire contact with the ground and preventing the vehicle from fully utilizing its deceleration.

[0004] Therefore, how to provide a method for adjusting the suspension damping coefficient to improve vehicle stability during braking has become an urgent technical problem to be solved. Summary of the Invention

[0005] This application provides a method, device, system, and storage medium for adjusting the suspension damping coefficient to improve vehicle stability during braking.

[0006] This application provides a method for adjusting the suspension damping coefficient, including: When the vehicle is braking, preset parameters of the vehicle are acquired, wherein the preset parameters include at least the longitudinal acceleration of the vehicle and the wheel speed of each wheel; Determine whether the vehicle is braking while cornering based on its preset parameters; When the vehicle is braking on a curve, calculate the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle. The target braking force for each wheel is determined based on the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle. Adjust the target damping coefficient of the suspension according to the target braking force of each wheel.

[0007] The beneficial effects of this application are as follows: When the vehicle is in a braking state, preset parameters of the vehicle are obtained, and it is determined whether the vehicle is braking in a curve based on these preset parameters. When the vehicle is braking in a curve, the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle are calculated, and the target braking force of each wheel is determined based on these factors. The target damping coefficient of the corresponding suspension is then adjusted according to the target braking force of each wheel. By considering the transfer of longitudinal and lateral loads, the target braking force of each vehicle is obtained, and the target damping coefficient of the corresponding suspension is determined based on the target braking force. This reduces the probability of vehicle skidding and fishtailing caused by tire load transfer due to vehicle pitch during curve braking, and improves vehicle stability during braking.

[0008] In one embodiment, determining whether the vehicle is braking while cornering based on preset vehicle parameters includes: Obtain the vehicle's steering wheel angle, vehicle steering tendency coefficient, and vehicle turning radius of curvature; When the steering wheel angle is greater than the first preset value, the vehicle steering trend coefficient is greater than the second preset value, and the vehicle's turning radius is less than the third preset value, the vehicle is determined to be in a cornering braking state.

[0009] In one embodiment, the calculation process of the vehicle steering trend coefficient includes: Obtain the inner and outer wheel speeds of the vehicle; Substituting the inner and outer wheel speeds of the vehicle into the following formula, the vehicle steering tendency coefficient is obtained:

[0010] Among them, K w w is the vehicle steering trend coefficient. outer w represents the speed of the outer wheel of the vehicle. inner This refers to the speed of the inner wheel of the vehicle.

[0011] In one embodiment, calculating the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle when the vehicle is braking in a curve includes: The dynamic loads on the front and rear axles of the vehicle are determined based on the vehicle's longitudinal acceleration, and the dynamic loads on the inner and outer wheels of the vehicle are determined based on the vehicle's lateral acceleration. The ratio of the dynamic load on the front axle to the dynamic load on the rear axle of the vehicle is determined as the longitudinal load transfer influence factor of the vehicle, and the ratio of the dynamic load on the inner wheel to the dynamic load on the outer wheel of the vehicle is determined as the lateral load transfer influence factor of the vehicle.

[0012] In one embodiment, determining the target braking force for each wheel based on the vehicle's longitudinal load transfer influence factor and lateral load transfer influence factor includes: The slip ratio of each wheel is calculated based on the vehicle's angular velocity and longitudinal acceleration. Calculate the maximum adhesion coefficient for each wheel based on the slip ratio of each wheel; Calculate the maximum braking force of each wheel based on the maximum adhesion coefficient of each wheel; The braking force of each wheel is corrected by the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle to obtain the target braking force of each wheel.

[0013] In one embodiment, the step of correcting the braking force of each wheel using the vehicle's longitudinal load transfer influence factor and lateral load transfer influence factor to obtain the target braking force of each wheel includes: Calculate the vehicle's maximum braking force based on the maximum braking force of each wheel; Substituting the vehicle's maximum braking force, longitudinal load transfer influence factor, and lateral load transfer influence factor into the following formula, the target braking force for each wheel is obtained:

[0014]

[0015]

[0016]

[0017] Among them, F fl The target braking force for the left front wheel; F fr The target braking force for the right front wheel; F rl The target braking force for the left rear wheel; F rr P1 represents the target braking force of the right rear wheel; F represents the maximum braking force of the vehicle; P1 represents the longitudinal load transfer influence factor of the vehicle; and P2 represents the lateral load transfer influence factor of the vehicle.

[0018] In one embodiment, adjusting the target damping coefficient of the suspension according to the target braking force of each wheel includes: Calculate the braking intensity of each wheel based on the target braking force of each vehicle; The target damping coefficient of the suspension is determined based on the braking intensity of each wheel.

[0019] This application also provides a suspension damping coefficient adjustment device, comprising: The acquisition module is used to acquire preset parameters of the vehicle when the vehicle is in a braking state, wherein the preset parameters include at least the longitudinal acceleration of the vehicle and the wheel speed of each wheel; The judgment module is used to determine whether the vehicle is braking while cornering based on preset vehicle parameters; The calculation module is used to calculate the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle when the vehicle is braking in a curve. The determination module is used to determine the target braking force of each wheel based on the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle. The adjustment module is used to adjust the target damping coefficient of the suspension according to the target braking force of each wheel.

[0020] In one embodiment, the determining module includes: The acquisition submodule is used to acquire the vehicle's steering wheel angle, vehicle steering trend coefficient, and vehicle turning radius of curvature. The first determination submodule is used to determine that the vehicle is in a cornering braking state when the steering wheel angle is greater than a first preset value, the vehicle steering trend coefficient is greater than a second preset value, and the vehicle's turning radius of curvature is less than a third preset value.

[0021] In one embodiment, the calculation process of the vehicle steering trend coefficient includes: Obtain the inner and outer wheel speeds of the vehicle; Substituting the inner and outer wheel speeds of the vehicle into the following formula, the vehicle steering tendency coefficient is obtained:

[0022] Among them, K w w is the vehicle steering trend coefficient. outer w represents the speed of the outer wheel of the vehicle. inner This refers to the speed of the inner wheel of the vehicle.

[0023] In one embodiment, the computing module includes: The second determining submodule is used to determine the dynamic load on the front axle and the dynamic load on the rear axle of the vehicle based on the vehicle's longitudinal acceleration, and to determine the dynamic load on the inner wheel and the dynamic load on the outer wheel of the vehicle based on the vehicle's lateral acceleration. The third determining submodule is used to determine the ratio of the dynamic load on the front axle to the dynamic load on the rear axle of the vehicle as the longitudinal load transfer influence factor of the vehicle, and to determine the ratio of the dynamic load on the inner wheel to the dynamic load on the outer wheel of the vehicle as the lateral load transfer influence factor of the vehicle.

[0024] In one embodiment, the determining module includes: The first calculation submodule is used to calculate the slip ratio of each wheel based on the vehicle's angular velocity and longitudinal acceleration; The second calculation submodule is used to calculate the maximum adhesion coefficient of each wheel based on the slip ratio of each wheel; The third calculation submodule is used to calculate the maximum braking force of each wheel based on the maximum adhesion coefficient of each wheel. The correction submodule is used to correct the braking force of each wheel by using the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle, so as to obtain the target braking force of each wheel.

[0025] In one embodiment, the correction submodule is further configured to: Calculate the vehicle's maximum braking force based on the maximum braking force of each wheel; Substituting the vehicle's maximum braking force, longitudinal load transfer influence factor, and lateral load transfer influence factor into the following formula, the target braking force for each wheel is obtained:

[0026]

[0027]

[0028]

[0029] Among them, F fl The target braking force for the left front wheel; F fr The target braking force for the right front wheel; F rl The target braking force for the left rear wheel; F rr P1 represents the target braking force of the right rear wheel; F represents the maximum braking force of the vehicle; P1 represents the longitudinal load transfer influence factor of the vehicle; and P2 represents the lateral load transfer influence factor of the vehicle.

[0030] In one embodiment, the adjustment module includes: The fourth calculation submodule is used to calculate the braking intensity of each wheel based on the target braking force of each vehicle. The adjustment submodule is used to adjust the target damping coefficient of the suspension based on the braking intensity of each wheel.

[0031] This application also provides a suspension damping coefficient adjustment system, comprising: At least one processor; and, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to implement the suspension damping coefficient adjustment method described in any of the above embodiments.

[0032] This application also provides a computer-readable storage medium, which, when the instructions in the storage medium are executed by a processor corresponding to a suspension damping coefficient adjustment system, enables the suspension damping coefficient adjustment system to implement the suspension damping coefficient adjustment method described in any of the above embodiments.

[0033] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings.

[0034] The technical solution of this application will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0035] The accompanying drawings are provided to further illustrate the present application and form part of the specification. They are used together with the embodiments of the present application to explain the application and do not constitute a limitation thereof. In the drawings: Figure 1 This is a flowchart of a method for adjusting the suspension damping coefficient in one embodiment of this application; Figure 2 This illustrates the relationship between the adhesion coefficient and slip ratio on a dry, hard road surface in one embodiment of this application. Figure 3 This is a schematic diagram of the structure of a suspension damping coefficient adjustment device according to an embodiment of this application; Figure 4 This is a schematic diagram of the hardware structure of a suspension damping coefficient adjustment system according to an embodiment of this application. Detailed Implementation

[0036] The preferred embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0037] Figure 1 This is a flowchart of a method for adjusting the suspension damping coefficient according to an embodiment of this application, as shown below. Figure 1 As shown, the method can be implemented as follows: S101-S105: In step S101, when the vehicle is in a braking state, preset parameters of the vehicle are acquired, wherein the preset parameters include at least the longitudinal acceleration of the vehicle and the wheel speed of each wheel; In step S102, it is determined whether the vehicle is braking while cornering based on the vehicle's preset parameters; In step S103, when the vehicle is braking on a curve, the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle are calculated. In step S104, the target braking force of each wheel is determined based on the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle. In step S105, the target damping coefficient of the suspension is adjusted according to the target braking force of each wheel.

[0038] In this application, when the vehicle is in a braking state, preset parameters of the vehicle are acquired, wherein the preset parameters include at least the longitudinal acceleration of the vehicle and the wheel speed of each wheel.

[0039] The vehicle's braking status is determined based on preset parameters. In this application, to more effectively control vehicle stability, the braking state is divided into straight-line braking and cornering braking; specifically, wheel speed difference analysis, vehicle posture sensors, and steering wheel angle signals are used to determine whether the vehicle is in a cornering braking condition. First, wheel speed difference analysis is performed to obtain the inner and outer wheel speeds. These inner and outer wheel speeds are then substituted into the following formula to obtain the vehicle steering trend coefficient:

[0040] Among them, K w w is the vehicle steering trend coefficient. outer The speed of the outer wheel, w inner This refers to the speed of the inner wheel.

[0041] It should be noted that when calculating the vehicle steering tendency coefficient, the inner and outer wheel speeds can be taken as the average of the wheel speeds on the same side, or the vehicle steering tendency coefficients corresponding to different axles can be calculated separately, and the maximum value can be taken as the judgment criterion. This application does not limit this. Because the difference in wheel speed between the inner and outer wheels increases significantly when the vehicle is braking in a curve, K... w When it is greater than the first preset value (calibration value).

[0042] Secondly, a lateral acceleration analysis is performed to examine its impact on the longitudinal velocity. Since the lateral acceleration and longitudinal velocity, along with the radius of curvature, satisfy the following relationship when the vehicle is cornering:

[0043] Among them, R curve Let be the radius of curvature, and v be the reference vehicle speed. This is lateral acceleration.

[0044] When a vehicle brakes while turning, the following will occur: (Lateral acceleration) increases significantly. Significantly reduced.

[0045] Next, the steering wheel angle signal is analyzed to reflect the driver's steering intention. Combining changes in lateral acceleration and longitudinal velocity with the steering wheel angle signal allows for a more accurate determination of whether the vehicle is braking in a curve.

[0046] Based on the foregoing analysis, when the steering wheel angle is greater than the first preset value, and Kw is greater than the second preset value, and R... curve When the value is less than the third preset value, the vehicle is determined to be in a cornering braking state.

[0047] When a vehicle is braking while cornering, the longitudinal load transfer influence factors and lateral load transfer influence factors are calculated. During braking, inertial forces cause axle load redistribution, increasing the front axle load and decreasing the rear axle load. Therefore, this application determines the dynamic loads of the front and rear axles based on the vehicle's longitudinal acceleration, and determines the dynamic loads of the inner and outer wheels based on the vehicle's lateral acceleration. Specifically, the dynamic load of the front axle is calculated using the following formula:

[0048] The dynamic load on the rear axle of the vehicle is calculated using the following formula:

[0049] Among them, F f For the dynamic load on the front axle of the vehicle; F r G represents the dynamic load on the rear axle of the vehicle; L represents the total vehicle weight; L represents the wheelbase; L1 and L2 represent the distances from the center of gravity to the front and rear axles, indicating the height of the center of gravity; a x ρ represents longitudinal braking deceleration; g represents gravitational acceleration.

[0050] Furthermore, during cornering braking, the centrifugal force and braking force cause uneven load distribution on the inner and outer wheels, leading to a tendency for the vehicle to tilt inwards. This results in load transfer between the left and right sides, with the inner load increasing and the outer load decreasing. Therefore, when determining that the vehicle is in a cornering braking state, the dynamic loads on the inner and outer wheels must be calculated. Specifically, the dynamic load on the inner wheel is calculated using the following formula:

[0051] The dynamic load on the outer wheel of the vehicle is calculated using the following formula:

[0052] Among them, F L For the dynamic load of the inner vehicle; F R G represents the dynamic load on the outgoing wheels; B represents the total vehicle weight; and B represents the vehicle wheelbase. denoted as lateral acceleration; m is the vehicle mass; hg is the height of the vehicle's center of gravity.

[0053] Then, the ratio of the dynamic load on the front axle to the dynamic load on the rear axle of the vehicle is determined as the longitudinal load transfer influence factor of the vehicle, and the ratio of the dynamic load on the inner wheel to the dynamic load on the outer wheel of the vehicle is determined as the lateral load transfer influence factor of the vehicle.

[0054] When a vehicle brakes in a straight line, the longitudinal load transfer and the front and rear forces are strongly correlated.

[0055]

[0056] Where P1 is the influencing factor of vehicle longitudinal load transfer; F f For the dynamic load on the front axle of the vehicle; F r This refers to the dynamic load on the rear axle of the vehicle.

[0057] The vehicle is currently in a steering condition, so the lateral load transfer during cornering braking needs to be considered. During cornering braking, the lateral load transfer and lateral force of the vehicle are strongly correlated.

[0058]

[0059] Where P2 is the influencing factor of lateral load transfer of the vehicle; F L For the dynamic load of the inner vehicle; F R For the dynamic load of the outgoing wheels.

[0060] The target braking force for each wheel is determined based on the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle. In this application, in order to determine the target braking force for each vehicle, the slip ratio of each wheel is first calculated based on the vehicle's angular velocity and longitudinal acceleration; specifically, the reference vehicle speed and the wheel speed of each wheel can be calculated based on the vehicle's angular velocity and longitudinal acceleration; then, the slip ratio of each wheel is calculated separately based on the reference vehicle speed and the wheel speed of each wheel.

[0061] The wheel speed of each wheel can be calculated using the following formula:

[0062] Where V is the current reference speed of the vehicle, ω is the angular velocity of the wheel, and R is the radius of the wheel.

[0063] For the vehicle's reference speed, a longitudinal acceleration factor can be introduced during braking to dynamically correct the reference speed. Specifically, this can be calculated using the following formula:

[0064] Where Vref is the current reference speed of the vehicle. P is the longitudinal acceleration of the vehicle, P is the gain coefficient (calibrated value), and Δ is the gain coefficient. This represents the maximum angular velocity change of each wheel at the current moment.

[0065] Calculate the slip ratio of each wheel based on the vehicle's reference speed and the wheel speed of each wheel:

[0066] Where λ is the wheel slip ratio, Vref is the current vehicle reference speed, and V is the current vehicle reference speed.

[0067] When λ=0, the wheels do not slip and roll completely with the ground. When 0<λ<1, the wheels partially slip, there is adhesion to the ground, and the vehicle is under control. When λ=1, the vehicle locks up completely and stops rolling.

[0068] Then, the maximum coefficient of adhesion for each wheel is calculated based on the slip ratio of each wheel. Accurate estimation of the coefficient of adhesion is crucial during emergency braking of the vehicle, as it directly determines the maximum braking force available. Figure 2 This embodiment illustrates the relationship between the coefficient of adhesion and the slip ratio on a dry, hard road surface. The coefficient of adhesion represents the ratio of the maximum friction force provided by the tire to the vertical load; a higher value indicates stronger braking force. The slip ratio reflects the relative degree of wheel rolling and sliding. Figure 2 As shown, the coefficient of friction reaches its peak when the slip ratio is approximately 15%-20%. At this point, the tire can provide the maximum longitudinal braking force, while the lateral coefficient of friction also remains at a high level. This means that the vehicle can effectively decelerate during emergency braking and also has good steering control. In this application, after calculating the slip ratio in real time, the maximum available coefficient of friction for the current road surface is estimated using the following model, thereby dynamically adjusting the braking force to prevent wheel lock-up and maintain steering capability.

[0069] μ=D sin(C arctan(B λ)) Where μ is the current maximum adhesion coefficient of the tire, λ is the wheel slip ratio, B is the stiffness factor, C is the shape factor, and D is the peak factor.

[0070] The model expresses the adhesion coefficient μ as a function of the wheel slip ratio λ. B, C, and D are empirical parameters that can be obtained by fitting experimental data and are used to adjust the shape and peak position of the curve.

[0071] Furthermore, the maximum braking force of each wheel can be calculated based on its maximum coefficient of adhesion. Since vehicles generate different longitudinal forces (friction forces) on different road surfaces, the magnitude of these forces is strongly correlated with the tire's slip ratio, tire lateral stiffness, vehicle slip angle, and coefficient of adhesion. The following mathematical model of a tire can describe the magnitude of the longitudinal force that a tire can generate on different road surfaces:

[0072] in, This refers to the longitudinal force of the vehicle, specifically the braking force generated between the tires and the ground. For the vehicle's slip ratio, Let denoted as the tire's lateral stiffness, α as the vehicle's slip angle, μ as the vehicle's road adhesion coefficient, and f as a correction function used to describe the tire saturation phenomenon that occurs when the tire force approaches the road adhesion limit. This function can be pre-determined through fitting multiple sets of experiments.

[0073] When f < 1, f = (2 - f)f, and the longitudinal force of the tire is in the nonlinear saturation region. f < 1 means that the force situation of the tire is complex, and it may have approached or reached the adhesion limit. The force will slow down with the increase of the slip ratio until it reaches a peak and then begins to decrease (entering the unstable region). When f ≥ 1, the longitudinal force of the tire is in the linear growth region, which usually corresponds to a small slip ratio. The tire force is far from reaching the limit, and the force and slip ratio can be considered to have a simple linear relationship.

[0074] The braking force of each wheel is then corrected by the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle to obtain the target braking force of each wheel.

[0075] The maximum braking force of the vehicle can be determined based on the maximum braking force of each wheel:

[0076] Where F is the vehicle's maximum braking force, F x_fl F x_fr F x_rl F x_rl These are the maximum braking forces for the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0077] Substituting the vehicle's maximum braking force, longitudinal load transfer influence factor, and lateral load transfer influence factor into the following formula, the target braking force for each wheel is obtained:

[0078]

[0079]

[0080]

[0081] Among them, F fl The target braking force for the left front wheel; F fr The target braking force for the right front wheel; F rl The target braking force for the left rear wheel; F rr P1 represents the target braking force of the right rear wheel; F represents the maximum braking force of the vehicle; P1 represents the longitudinal load transfer influence factor of the vehicle; and P2 represents the lateral load transfer influence factor of the vehicle.

[0082] Finally, the target damping coefficient of the suspension is adjusted according to the target braking force of each wheel.

[0083] The braking intensity of each wheel is calculated based on the target braking force of each vehicle, and the damping coefficient of the suspension is adjusted according to the braking intensity of each wheel.

[0084] First, the braking intensity B of each wheel is calculated through the chassis cooperative control system. brake : B brake = F * Q; Where F represents the target braking force of the current wheel, and Q is the proportional coefficient (calibration value).

[0085] Then, the suspension system calculates the target damping coefficient corresponding to the suspension based on the braking intensity sent by the braking system: C brake =C normal +K*B brake ; Among them, C brake C is the target suspension damping coefficient. normal Where K is the reference damping value, and B is the calibration proportional coefficient. brake This is the braking intensity factor for the current wheel.

[0086] Therefore, for a four-wheeled vehicle, each wheel specifically has: C brakefl =C normalfl + K*B brakefl ; C brakefr =C normalfr + K*B brakefr ; C brakerl =C normalrl + K*B brakerl ; C brakerr =C normalrr + K*B brakerr .

[0087] Among them, C brakefl C brakefr C brakerl C brakerr Let K be the target suspension damping coefficient for the four wheels, and K be the proportional coefficient.

[0088] The beneficial effects of this application are as follows: When the vehicle is in a braking state, preset parameters of the vehicle are obtained, and it is determined whether the vehicle is braking in a curve based on these preset parameters. When the vehicle is braking in a curve, the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle are calculated, and the target braking force of each wheel is determined based on these factors. The target damping coefficient of the corresponding suspension is then adjusted according to the target braking force of each wheel. By considering the transfer of longitudinal and lateral loads, the target braking force of each vehicle is obtained, and the target damping coefficient of the corresponding suspension is determined based on the target braking force. This reduces the probability of vehicle skidding and fishtailing caused by tire load transfer due to vehicle pitch, and improves vehicle stability during braking.

[0089] In one embodiment, step S102 above can be implemented as steps A1-A2 as follows: In step A1, the vehicle's steering wheel angle, vehicle steering trend coefficient, and vehicle turning radius of curvature are obtained; In step A2, when the steering wheel angle is greater than the first preset value, the vehicle steering trend coefficient is greater than the second preset value, and the radius of curvature of the vehicle turning is less than the third preset value, the vehicle is determined to be in a cornering braking state.

[0090] In one embodiment, the calculation process of the vehicle steering trend coefficient in step A1 above can be implemented as follows: steps A11-A12: In step A11, the inner wheel speed and outer wheel speed of the vehicle are obtained; In step A12, the inner and outer wheel speeds of the vehicle are substituted into the following formula to obtain the vehicle steering tendency coefficient:

[0091] Among them, K w w is the vehicle steering trend coefficient. outer w represents the speed of the outer wheel of the vehicle. inner This refers to the speed of the inner wheel of the vehicle.

[0092] In one embodiment, step S103 above can be implemented as steps B1-B2 as follows: In step B1, the dynamic loads of the front axle and rear axle of the vehicle are determined based on the vehicle's longitudinal acceleration, and the dynamic loads of the inner and outer wheels of the vehicle are determined based on the vehicle's lateral acceleration. In step B2, the ratio of the dynamic load on the front axle to the dynamic load on the rear axle of the vehicle is determined as the longitudinal load transfer influence factor of the vehicle, and the ratio of the dynamic load on the inner wheel to the dynamic load on the outer wheel of the vehicle is determined as the lateral load transfer influence factor of the vehicle.

[0093] In one embodiment, step S104 above can be implemented as steps C1-C4 as follows: In step C1, the slip ratio of each wheel is calculated based on the vehicle's angular velocity and longitudinal acceleration; In step C2, the maximum coefficient of adhesion for each wheel is calculated based on the slip ratio of each wheel; In step C3, the maximum braking force of each wheel is calculated based on the maximum adhesion coefficient of each wheel; In step C4, the braking force of each wheel is corrected by the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle to obtain the target braking force of each wheel.

[0094] In one embodiment, step S104 above can be implemented as steps C41-C42: In step C41, the maximum braking force of the vehicle is calculated based on the maximum braking force of each wheel; In step C42, the maximum braking force of the vehicle and the longitudinal load transfer influence factor and lateral load transfer influence factor of the vehicle are substituted into the following formula to obtain the target braking force of each wheel:

[0095]

[0096]

[0097]

[0098] Among them, F fl The target braking force for the left front wheel; F fr The target braking force for the right front wheel; F rl The target braking force for the left rear wheel; F rr P1 represents the target braking force of the right rear wheel; F represents the maximum braking force of the vehicle; P1 represents the longitudinal load transfer influence factor of the vehicle; and P2 represents the lateral load transfer influence factor of the vehicle.

[0099] In one embodiment, step S105 above can be implemented as steps D1-D2 as follows: In step D1, the braking intensity of each wheel is calculated based on the target braking force of each vehicle; In step D2, the target damping coefficient of the suspension is determined based on the braking intensity of each wheel.

[0100] Figure 3 This is a schematic diagram of the structure of a suspension damping coefficient adjustment device according to an embodiment of this application, as shown below. Figure 3 As shown, the device includes: The acquisition module 301 is used to acquire preset parameters of the vehicle when the vehicle is in a braking state, wherein the preset parameters include at least the longitudinal acceleration of the vehicle and the wheel speed of each wheel; The judgment module 302 is used to determine whether the vehicle is braking while cornering based on preset parameters of the vehicle; The calculation module 303 is used to calculate the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle when the vehicle is braking in a curve. The determination module 304 is used to determine the target braking force of each wheel based on the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle. The adjustment module 305 is used to adjust the target damping coefficient of the suspension according to the target braking force of each wheel.

[0101] In one embodiment, the determining module includes: The acquisition submodule is used to acquire the vehicle's steering wheel angle, vehicle steering trend coefficient, and vehicle turning radius of curvature. The first determination submodule is used to determine that the vehicle is in a cornering braking state when the steering wheel angle is greater than a first preset value, the vehicle steering trend coefficient is greater than a second preset value, and the vehicle's turning radius of curvature is less than a third preset value.

[0102] In one embodiment, the calculation process of the vehicle steering trend coefficient includes: Obtain the inner and outer wheel speeds of the vehicle; Substituting the inner and outer wheel speeds of the vehicle into the following formula, the vehicle steering tendency coefficient is obtained:

[0103] Among them, K w w is the vehicle steering trend coefficient. outer w represents the speed of the outer wheel of the vehicle. inner This refers to the speed of the inner wheel of the vehicle.

[0104] In one embodiment, the computing module includes: The second determining submodule is used to determine the dynamic load on the front axle and the dynamic load on the rear axle of the vehicle based on the vehicle's longitudinal acceleration, and to determine the dynamic load on the inner wheel and the dynamic load on the outer wheel of the vehicle based on the vehicle's lateral acceleration. The third determining submodule is used to determine the ratio of the dynamic load on the front axle to the dynamic load on the rear axle of the vehicle as the longitudinal load transfer influence factor of the vehicle, and to determine the ratio of the dynamic load on the inner wheel to the dynamic load on the outer wheel of the vehicle as the lateral load transfer influence factor of the vehicle.

[0105] In one embodiment, the determining module includes: The first calculation submodule is used to calculate the slip ratio of each wheel based on the vehicle's angular velocity and longitudinal acceleration; The second calculation submodule is used to calculate the maximum adhesion coefficient of each wheel based on the slip ratio of each wheel; The third calculation submodule is used to calculate the maximum braking force of each wheel based on the maximum adhesion coefficient of each wheel. The correction submodule is used to correct the braking force of each wheel by using the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle, so as to obtain the target braking force of each wheel.

[0106] In one embodiment, the correction submodule is further configured to: Calculate the vehicle's maximum braking force based on the maximum braking force of each wheel; Substituting the vehicle's maximum braking force, longitudinal load transfer influence factor, and lateral load transfer influence factor into the following formula, the target braking force for each wheel is obtained:

[0107]

[0108]

[0109]

[0110] Among them, F fl The target braking force for the left front wheel; F fr The target braking force for the right front wheel; F rl The target braking force for the left rear wheel; F rr P1 represents the target braking force of the right rear wheel; F represents the maximum braking force of the vehicle; P1 represents the longitudinal load transfer influence factor of the vehicle; and P2 represents the lateral load transfer influence factor of the vehicle.

[0111] In one embodiment, the adjustment module includes: The fourth calculation submodule is used to calculate the braking intensity of each wheel based on the target braking force of each vehicle. The adjustment submodule is used to adjust the target damping coefficient of the suspension based on the braking intensity of each wheel.

[0112] Figure 4 This is a schematic diagram of the hardware structure of a suspension damping coefficient adjustment system according to an embodiment of this application, as shown below. Figure 4 As shown, the suspension damping coefficient adjustment system includes: At least one processor 420; and, Memory 404 communicatively connected to the at least one processor 420; wherein, The memory 404 stores instructions that can be executed by the at least one processor 420 to implement the suspension damping coefficient adjustment method described in any of the above embodiments.

[0113] Reference Figure 4 The suspension damping coefficient adjustment system 400 may include one or more of the following components: processing component 402, memory 404, power supply component 406, input / output (I / O) interface 408, sensor component 410, and communication component 412.

[0114] Processing component 402 typically controls the overall operation of the suspension damping coefficient adjustment system 400. Processing component 402 may include one or more processors 420 to execute instructions to complete all or part of the steps of the method described above. Furthermore, processing component 402 may include one or more modules to facilitate interaction between processing component 402 and other components. The processor 420 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0115] Memory 404 is configured to store various types of data to support the operation of the suspension damping coefficient adjustment system 400. Examples of this data include instructions for any application or method operating on the suspension damping coefficient adjustment system 400. Memory 404 may be an internal storage unit of the terminal device, such as a hard disk or memory of the terminal device. Memory 404 may also be an external storage device of the terminal device, such as a plug-in hard disk equipped on the terminal device. Memory 404 may be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. Memory 404 is used to store programs and data required by this application. Memory 404 may also be used to temporarily store data that has been output or will be output.

[0116] The power supply assembly 406 provides power to the various components of the suspension damping coefficient adjustment system 400. The power supply assembly 406 may include a power management system, one or more power sources, and other components associated with generating, managing, and distributing power to the suspension damping coefficient adjustment system 400.

[0117] I / O interface 408 provides an interface between processing component 402 and peripheral interface modules, such as keyboards, click wheels, buttons, etc.

[0118] Sensor assembly 410 includes one or more sensors for providing a status assessment of various aspects of the suspension damping coefficient adjustment system 400. Additionally, sensor assembly 410 can detect the on / off state of the suspension damping coefficient adjustment system 400, the relative positioning of components, and the operating status of the suspension damping coefficient adjustment system 400 or a component of the suspension damping coefficient adjustment system 400. In some embodiments, sensor assembly 410 may include an accelerometer, gyroscope, magnetometer, pressure sensor, or temperature sensor, etc.

[0119] Communication component 412 is configured to enable the suspension damping coefficient adjustment system 400 to communicate with other devices and cloud platforms via wired or wireless means. The suspension damping coefficient adjustment system 400 can access wireless networks based on communication standards, such as WiFi, 2G, or 3G, or combinations thereof. In one exemplary embodiment, communication component 416 receives broadcast signals or broadcast-related information from an external broadcast management system via a broadcast channel. In one exemplary embodiment, communication component 416 also includes a near-field communication (NFC) module to facilitate short-range communication. For example, the NFC module may be implemented based on radio frequency identification (RFID) technology, Infrared Data Association (IrDA) technology, ultra-wideband (UWB) technology, Bluetooth (BT) technology, and other technologies.

[0120] In an exemplary embodiment, the suspension damping coefficient adjustment system 400 may be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to perform the suspension damping coefficient adjustment method described in any of the above embodiments.

[0121] This application also provides a computer-readable storage medium, which, when the instructions in the storage medium are executed by a processor corresponding to a suspension damping coefficient adjustment system, enables the suspension damping coefficient adjustment system to implement the suspension damping coefficient adjustment method described in any of the above embodiments.

[0122] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application 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 and optical storage) containing computer-usable program code.

[0123] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1A device that provides the functions specified in one or more boxes.

[0124] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0125] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0126] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method of adjusting a suspension damping coefficient, characterized by, The method comprises the following steps: When the vehicle is in a braking state, preset parameters of the vehicle are acquired, wherein the preset parameters at least include longitudinal acceleration of the vehicle and wheel speed of each wheel; It is judged whether the vehicle is in a curve braking state according to the preset parameters of the vehicle; When the vehicle is in the curve braking state, a longitudinal load transfer influence factor and a lateral load transfer influence factor of the vehicle are calculated; Target braking forces of each wheel are determined according to the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle; Target damping coefficients of corresponding suspensions are adjusted according to the target braking forces of each wheel.

2. The method of claim 1, wherein, The step of judging whether the vehicle is in the curve braking state according to the preset parameters of the vehicle comprises the following steps: A steering wheel angle of the vehicle, a vehicle turning tendency coefficient and a curvature radius of the vehicle turning are acquired; When the steering wheel angle is greater than a first preset value, the vehicle turning tendency coefficient is greater than a second preset value and the curvature radius of the vehicle turning is less than a third preset value, it is determined that the vehicle is in the curve braking state.

3. The method of claim 2, wherein, The calculation process of the vehicle turning tendency coefficient comprises the following steps: Wheel speeds of an inner side and an outer side of the vehicle are acquired; The wheel speeds of the inner side and the outer side of the vehicle are substituted into the following formula to obtain the vehicle turning tendency coefficient: wherein K w is a vehicle turning tendency coefficient; w outer is an outer wheel speed of the vehicle, w inner is an inner wheel speed of the vehicle.

4. The method of claim 1, wherein, The step of calculating the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle when the vehicle is in the curve braking state comprises the following steps: The front axle dynamic load and the rear axle dynamic load of the vehicle are determined according to the longitudinal acceleration of the vehicle, and the inner side wheel dynamic load and the outer side wheel dynamic load of the vehicle are determined according to the lateral acceleration of the vehicle; The ratio of the front axle dynamic load and the rear axle dynamic load of the vehicle is determined as the longitudinal load transfer influence factor of the vehicle, and the ratio of the inner side wheel dynamic load and the outer side wheel dynamic load of the vehicle is determined as the lateral load transfer influence factor of the vehicle.

5. The method of claim 1, wherein, The step of determining the target braking forces of each wheel according to the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle comprises the following steps: The slip rate of each wheel is calculated according to the vehicle angular velocity and the longitudinal acceleration; The maximum adhesion coefficient of each wheel is calculated according to the slip rate of each wheel; The maximum braking force of each wheel is calculated according to the maximum adhesion coefficient of each wheel; The braking force of each wheel is corrected through the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle to obtain the target braking force of each wheel.

6. The method of claim 5, wherein, The step of correcting the braking force of each wheel through the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle to obtain the target braking force of each wheel comprises the following steps: The maximum braking force of the vehicle is calculated according to the maximum braking force of each wheel; The maximum braking force of the vehicle, the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle are substituted into the following formula to obtain the target braking force of each wheel: F fl is a target braking force of the left front wheel; F fr is a target braking force of the right front wheel; F rl is a target braking force of the left rear wheel; F rr is a target braking force of the right rear wheel; F is a maximum braking force of the vehicle; P1 is a longitudinal load transfer influence factor of the vehicle; and P2 is a lateral load transfer influence factor of the vehicle.

7. The method of claim 1, wherein, The step of adjusting the target damping coefficient of the corresponding suspension according to the target braking force of each wheel comprises the following steps: The braking intensity of each wheel is calculated according to the target braking force of each vehicle; The target damping coefficient of the suspension is determined according to the braking intensity of each wheel.

8. A device for adjusting the damping coefficient of a suspension, characterized in that, The method comprises the following steps: An acquisition module is configured to acquire preset parameters of the vehicle when the vehicle is in a braking state, wherein the preset parameters at least include a longitudinal acceleration of the vehicle and wheel speeds of each wheel; A judgment module is configured to judge whether the vehicle is in a curve braking according to the preset parameters of the vehicle; A calculation module is configured to calculate a longitudinal load transfer influence factor and a lateral load transfer influence factor of the vehicle when the vehicle is in the curve braking; A determination module is configured to determine target braking forces of each wheel according to the longitudinal load transfer influence factor and the lateral load transfer influence factor of the vehicle; An adjustment module is configured to adjust target damping coefficients of corresponding suspensions according to the target braking forces of each wheel.

9. A suspension damping coefficient adjustment system characterized by, comprise: at least one processor; and a memory connected with the at least one processor in communication; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to implement the adjustment method of the suspension damping coefficient as claimed in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, When the instructions in the storage medium are executed by the processor corresponding to the adjustment system of the suspension damping coefficient, the adjustment system of the suspension damping coefficient can implement the adjustment method of the suspension damping coefficient as claimed in any one of claims 1-7.

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