Semi-active suspension control method, system and vehicle based on vehicle performance

Abstract

The present invention discloses a semi-active suspension control method, system and vehicle based on vehicle performance, which comprises the following steps: S1, obtaining vehicle state information; S2, analyzing and calculating a first damping force based on the obtained vehicle state information for the purpose of ensuring the smooth driving performance of the vehicle; S3, analyzing and calculating a second damping force based on the obtained vehicle state information for the purpose of ensuring the handling stability performance of the vehicle; S4, performing weighted summation on the first damping force and the second damping force to obtain a suspension target damping force; S5, adjusting the current of the adjustable damping shock absorber drive control unit according to the obtained suspension target damping force. Starting from the vehicle performance, a control method is proposed for the smooth driving performance and the handling stability performance of the vehicle, which can better balance the vertical, longitudinal and lateral multi-dimensional performance requirements, achieve better balance of more performances, and avoid the abrupt feeling caused by the switching of different task states.

Description

Technical Field

[0001] The present invention relates to the technical field of suspension system control, and particularly to a semi-active suspension control method, system and vehicle based on vehicle performance. Background Art

[0002] With the popularization of new energy vehicle models, more and more vehicle models are equipped with semi-active suspensions. Among them, the most commonly used shock absorbers are solenoid valve shock absorbers and magnetorheological shock absorbers. The main purpose of major vehicle manufacturers to equip electronically controlled shock absorbers is to improve the overall vehicle performance and provide an excellent user experience. To obtain higher and better performance, on the one hand, excellent hardware capabilities are required, such as high timeliness, a wide adjustable damping force bandwidth, and high reliability; on the other hand, excellent software capabilities are needed, and among them, the application layer algorithm in the software is the most important, which determines the response quality of the entire system. For example, the current invention patent "Electronic Control Device for Continuously Adjustable Damping Semi-Active Suspension of Automobile" (Application No.: 201921970756.3, Publication Date: 2020.06.26) mainly focuses on the hardware design, briefly describes some electronic control methods, and performs task control according to the vehicle running state, including vehicle body vertical vibration control, vehicle body pitch control, vehicle body roll control, wheel vertical vibration control, and vehicle instability control. However, when grading and arbitrating each task, the roll control level is superior to the pitch control, and the handling and stability control is generally superior to the ride comfort control, resulting in a relatively small matching space for comfort-oriented vehicles in actual vehicle applications.

[0003] CN112339517A discloses a semi-active suspension control method and control system, which mainly uses a switch-type "on-off" skyhook algorithm. Based on an expert database, the minimum damping coefficient C min and the maximum damping coefficient C max that can be achieved by a damping adjustable shock absorber corresponding to different sprung accelerations are obtained to get the basic damping coefficient, and then it is corrected through vehicle attitude determination. The two are fused and jointly output the damping coefficient to adjust and control the damping adjustable shock absorber. However, the basic damping uses a switch-type method, resulting in the damping force switching back and forth, which is prone to chattering; secondly, there is a confusion between vehicle roll control in comfort and vehicle roll control in handling and stability. For chassis electronic control algorithms, it is still recommended to formulate diversified strategies based on rich usage scenarios to better meet user needs.

[0004] A vehicle semi-active suspension control method, device, vehicle and medium disclosed in CN114919365A and a skyhook damping control method, device, computer device and medium disclosed in CN114905908A both conduct detailed algorithm research based on a certain working condition, and do not propose an architecture and method in an all-round manner based on vehicle performance.

[0005] Referring to many past patents, complex algorithm development has mainly been carried out for vertical vibration control. For example, sliding mode control, neural networks, particle swarm method, etc. all require an accurate vehicle model, with complex calculation methods, high computing power requirements, and low applicability. Or, it does not start from the overall vehicle performance, but only studies the ride comfort or only for special protrusion conditions. Summary of the Invention

[0006] The object of the present invention is to provide a semi-active suspension control method, system and vehicle based on the overall vehicle performance. Starting from the overall vehicle performance, a control method is proposed for the ride comfort performance and the handling stability performance of the vehicle during driving, which can better take into account the performance requirements in multiple dimensions of vertical, longitudinal, and lateral directions, and consider special working conditions for the final output of the damping force, so as to better balance more performances, and at the same time avoid the abrupt feeling brought about when switching between different task states.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A semi-active suspension control method based on the overall vehicle performance, which includes the following steps:

[0009] S1, obtaining vehicle state information;

[0010] S2, based on the obtained vehicle state information and aiming at ensuring the ride comfort performance of the vehicle, analyzing and calculating to obtain a first damping force;

[0011] S3, based on the obtained vehicle state information and aiming at ensuring the handling stability performance of the vehicle, analyzing and calculating to obtain a second damping force;

[0012] S4, performing weighted summation on the first damping force and the second damping force to obtain the target damping force of the suspension;

[0013] S5, adjusting the current of the adjustable damping shock absorber drive control unit according to the target damping force of the suspension obtained in S4.

[0014] Furthermore, the first damping force is based on at least one of the vertical vibration control of the unsprung mass, the vertical vibration control of the sprung mass, the body pitch motion control based on body pitch comfort, and the body roll motion control based on body roll comfort;

[0015] The vertical vibration control based on the sprung mass is: multiplying the weighted fusion of the sprung acceleration and the sprung speed in the vehicle state information by the suspension movement speed, and then performing two-dimensional look-up of the product operation result and the vehicle speed to obtain the suspension damping coefficient C spmas ;

[0016] The vertical vibration control based on the unsprung mass is: performing two-dimensional look-up of the unsprung acceleration in the vehicle state information and the vehicle speed to obtain the suspension damping coefficient Cw ;

[0017] The vehicle body pitching motion control based on vehicle body pitching comfort is: performing two-dimensional look-up of the vehicle pitching angular velocity and vehicle speed in the vehicle state information to obtain the suspension damping coefficient C θ ;

[0018] The vehicle body roll motion control based on vehicle body roll comfort is: performing two-dimensional look-up of the vehicle roll angular velocity and vehicle speed in the vehicle state information to obtain the suspension damping coefficient

[0019] The first damping force F Ride The calculation formula is: In the formula, v def is the relative vibration speed of the unsprung mass and sprung mass, R spmas is the weight coefficient based on the vertical vibration control of the sprung mass, R w is the weight coefficient based on the vertical vibration control of the unsprung mass, R θ is the weight coefficient of the vehicle body pitching motion control based on vehicle body pitching comfort, is the weight coefficient of the vehicle body roll motion control based on vehicle body roll comfort.

[0020] Furthermore, the specific weighted fusion of the sprung acceleration and sprung speed is as follows: In the formula, Z rh is the fusion vibration coefficient, k1 is the weight coefficient of the sprung acceleration, is the sprung acceleration, k2 is the weight coefficient of the sprung speed, is the sprung speed, v def is the relative vibration speed of the unsprung mass and sprung mass.

[0021] Furthermore, in S3, the calculation formula of the second damping force F Handing is: F Handing = v def × (C x × R x + C y × R y ), in the formula, v def is the relative vibration speed of the unsprung mass and sprung mass, C x is the longitudinal damping coefficient, R x is the weight coefficient of the longitudinal damping force, C y is the lateral damping coefficient, R y is the weight coefficient of the lateral damping force.

[0022] Further, the longitudinal damping coefficient is obtained as follows: based on the vehicle longitudinal acceleration, brake pedal stroke, accelerator pedal opening, vehicle speed, and considering the front and rear suspensions separately for two-dimensional look-up tables, the damping coefficient required for braking and the damping coefficient required for acceleration are output, and the maximum value of the damping coefficient required for braking and the damping coefficient required for acceleration is used as the longitudinal damping coefficient;

[0023] The lateral damping coefficient is obtained as follows: based on the vehicle lateral acceleration, steering wheel angle, and steering wheel angular velocity, and considering the left and right of the front and rear suspensions separately for two-dimensional look-up tables, the damping coefficient required for lateral cornering, i.e., the lateral damping coefficient, is output.

[0024] Further, in S4, the target damping force F damp of the suspension is calculated by the formula: F damp = F Ride × R R + F Handing × R H , where F Ride is the first damping force, F Handing is the second damping force, R R is the first weight coefficient, and R H is the second weight coefficient;

[0025] The first weight coefficient and the second weight coefficient are pre-calibrated according to different driving modes.

[0026] Further, based on different road surface conditions and vehicle speeds, the maximum acceptable damping force and the minimum damping force of the road surface are calibrated, and the target damping force of the suspension obtained in S4 is limited and output.

[0027] Further, according to the height sensor signal, it is judged whether the vehicle is within the limit travel range. When the preset travel threshold is reached, a correction coefficient is calibrated according to the height signal and the vehicle speed, and the correction coefficient is multiplied by the target damping force of the suspension obtained in S4 to obtain the final target damping force of the suspension.

[0028] A semi-active suspension control device based on the vehicle performance, which can execute the steps of the semi-active suspension control method based on the vehicle performance according to the present invention, includes: a vehicle state information acquisition module for acquiring vehicle state information; a vehicle driving ride performance calculation module for analyzing and calculating the first damping force based on the acquired vehicle state information with the aim of ensuring the vehicle driving ride performance; a vehicle driving handling stability performance calculation module for analyzing and calculating the second damping force based on the acquired vehicle state information with the aim of ensuring the vehicle driving handling stability performance; a weighted output module for performing weighted summation on the first damping force and the second damping force to obtain the target damping force of the suspension; and adjusting the current of the adjustable damping shock absorber drive control unit according to the obtained target damping force of the suspension.

[0029] A vehicle comprises the semi-active suspension control device based on whole vehicle performance described in the present invention.

[0030] Beneficial effects of the present invention:

[0031] 1. The present invention is based on the performance of the whole vehicle, taking into account the vehicle's smoothness, handling stability, and extreme special situations, and proposes an architecture and method that takes into account all aspects of performance. The application scenarios are richer, the vehicle application effect is better, and it is closer to user needs.

[0032] 2. The present invention proposes four aspects for ride comfort, involving three directions, including algorithm strategies for vertical, pitch, and roll comfort. The vertical aspect also takes into account the vibration of the sprung and unsprung parts. The weight coefficients of the four aspects will be calibrated according to performance requirements to achieve better results.

[0033] 3. The present invention proposes a strategy algorithm for lateral and longitudinal transient, steady-state and limit performance in view of the vehicle's driving handling stability. The damping force required is not calibrated solely based on acceleration, but also includes brake pedal travel, accelerator pedal opening, steering wheel angle and steering wheel angular velocity for calibration, which is more comprehensive and has better effects.

[0034] 4. The present invention provides arbitration methods within different modules, such as the handling stability module, and also provides arbitration methods between higher-level modules, such as the handling stability and ride comfort modules. Different driving modes are taken into consideration to achieve performance requirements between different modes. The acceptable maximum and minimum damping coefficients are confirmed according to different road surface grades, and the final output coefficient is limited.

[0035] 5. The present invention uses each module to perform calculations simultaneously and arbitrates at the end, avoiding the repeated switching between working conditions caused by sub-task control (when a certain trigger condition is met, only the strategy of the module is executed), which leads to sudden changes in damping force and reduces user experience.

[0036] 6. The present invention avoids iterative calculations of complex algorithms and directly calibrates through multiple parameters and multiple dimensions, which has a fast response and is easier to use in subsequent mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a flow chart of the semi-active suspension control method based on vehicle performance according to the present invention;

[0038] Figure 2 This is a flow chart based on the calculation of vehicle driving smoothness performance according to the present invention;

[0039] Figure 3 It is the calibration reference diagram of the sprung mass vibration control of the present invention;

[0040] Figure 4 The flowchart of the vehicle driving handling stability performance calculation according to the present invention;

[0041] Figure 5 It is a weighted calculation flowchart of the first damping force and the second damping force. Specific embodiments

[0042] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand the other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, rather than for limiting the protection scope of the present invention.

[0043] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The types, quantities, and proportions of the components in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0044] Embodiment 1, see Figure 1 , the semi-active suspension control method based on vehicle performance shown, which includes the following steps:

[0045] S1. Obtain vehicle state information through the vehicle state information acquisition module, including obtaining CAN signals, processing sensor transmission signals, and estimating vehicle states. The vehicle CAN signals are mainly converted according to the vehicle DBC parameter table (offset, amplification factor, limit value). The processing of sensor transmission signals mainly includes the body acceleration sensor transmitting acceleration signals, or the height sensor transmitting the displacement signal of the body relative to the unsprung mass, or the unsprung acceleration sensor testing the unsprung acceleration, or the 3-axis body acceleration signals and 3-axis body angular velocity signals transmitted by the IMU. They can be freely combined to form sensor architectures such as "4 + 3", "1 + 2", "1 + 3", etc., and vehicle state estimation can be performed through geometric methods or filtering algorithms such as Kalman. Preferably, the "4 + 3" sensor architecture adopted in the present invention, that is, estimating the unsprung acceleration, estimating the sprung speed, etc. through 4 height sensors and 3 sprung acceleration sensors. There will be no excessive elaboration in the present invention, nor is it limited to any of the above combined sensor architectures. The semi-active suspension control method based on vehicle performance proposed by the present invention can be adopted.

[0046] S2. Based on the obtained vehicle state information and aiming to ensure the smooth driving performance of the vehicle, analyze and calculate the first damping force F through the vehicle ride comfort performance calculation module Ride .

[0047] The first damping force is based on at least one of the vertical vibration control of the unsprung mass, the vertical vibration control of the sprung mass, the pitch motion control of the vehicle body based on the pitch comfort of the vehicle body, and the roll motion control of the vehicle body based on the roll comfort of the vehicle body. The four sub-modules simultaneously receive the signals transmitted by the vehicle state information acquisition module and operate simultaneously according to the response module strategy to output the corresponding suspension damping coefficient. Of course, the number of modules can be adjusted according to performance requirements later, and the above four major modules can be freely combined. Preferably, the four major modules perform parallel calculations, but due to factors such as cost, only one, two, or three modules can also be selected.

[0048] The vertical vibration control based on the sprung mass is as follows: The traditional skyhook control strategy or ADD control strategy is of the "on-off" switch type, and there is a chattering phenomenon of repeated damping switching in the actual application process, and the damping force only switches between the maximum and the minimum, which is not suitable for rich user usage scenarios. In the present invention, the skyhook control (shyhook) is used to improve the vehicle body vibration in the low-frequency range, and the ADD control mainly improves the vehicle body vibration in the medium-high frequency range. The two are fused to obtain a fusion vibration coefficient Z rh , that is, the sprung acceleration and the sprung speed in the vehicle state information are weighted and fused and then multiplied by the suspension movement speed. See Figure 3 , and then the result of the multiplication operation is used to perform a two-dimensional look-up table with the vehicle speed V spd to obtain the suspension damping coefficient C at different fusion vibration coefficients and different vehicle speeds spmas ; then the vehicle body vibration in the full frequency range can be controlled. Among them, the specific weighted fusion of the sprung acceleration and the sprung speed is as follows: In the formula, Z rh is the fusion vibration coefficient, k1 is the weight coefficient of the sprung acceleration, is the sprung acceleration, k2 is the weight coefficient of the sprung speed, is the sprung speed, v def is the relative vibration speed of the sprung mass and the unsprung mass.

[0049] The vertical vibration control based on the unsprung mass is as follows: mainly based on the vibration degree of the unsprung mass and its change trend with the vehicle speed, a two-dimensional look-up table is performed, that is, the unsprung acceleration and the vehicle speed in the vehicle state information are used to perform a two-dimensional look-up table to obtain the suspension damping coefficient C w to suppress the vibration of the unsprung mass, that is, the wheel vibration phenomenon. Subsequently, this table can be calibrated according to the actual vehicle performance.

[0050] The pitch motion control of the vehicle body based on the pitch comfort of the vehicle body is as follows: mainly calibrated based on the vehicle pitch angular rate and the vehicle speed. The vehicle pitch angular velocity and the vehicle speed in the vehicle state information are used to perform a two-dimensional look-up table to obtain the suspension damping coefficient C θ, to control the vehicle pitch ride comfort.

[0051] The body roll motion control based on body roll comfort is mainly calibrated based on the vehicle roll angle rate and vehicle speed, that is, the vehicle roll angle speed and vehicle speed in the vehicle state information are used for two-dimensional look-up to obtain the suspension damping coefficient , to control the vehicle roll ride comfort.

[0052] Each control is calibrated according to the corresponding characteristic road surface. For example, the body pitch motion control based on body pitch comfort is calibrated using a long-wave road surface, and the body roll motion control based on body roll comfort is calibrated using a damaged road surface with left-right inconsistency; the vertical vibration control of the unsprung mass and the vertical vibration control of the sprung mass are mainly calibrated according to various characteristic road surfaces with different road grades. First, various z of vibration degrees are calibrated according to different road surfaces rh and the unsprung vibration acceleration, and then the optimal damping coefficient for different road surfaces is calibrated according to the vehicle speed.

[0053] Calibrate the weight coefficients of the vertical vibration control of the sprung mass, the vertical vibration control of the unsprung mass, the body pitch motion control based on body pitch comfort, and the body roll motion control based on body roll comfort according to the actual performance requirements, and then obtain the first damping force F Ride The calculation formula is:

[0054] In the formula, v def is the relative vibration speed of the sprung mass and the unsprung mass, R spmas is the weight coefficient of the vertical vibration control of the sprung mass, R w is the weight coefficient of the vertical vibration control of the unsprung mass, R θ is the weight coefficient of the body pitch motion control based on body pitch comfort, is the weight coefficient of the body roll motion control based on body roll comfort.

[0055] S3, based on the obtained vehicle state information and aiming to ensure the vehicle driving handling stability performance, calculate and obtain the second damping force through the vehicle driving handling stability calculation module.

[0056] The calculation formula of the second damping force F Handing is: F Handing =v def ×(C x ×R x +C y ×R y ), in the formula, v def is the relative vibration speed of the sprung mass and the unsprung mass, C x is the longitudinal damping coefficient, Rx is the weight coefficient of the longitudinal damping force, C y is the lateral damping coefficient, R y is the weight coefficient of the lateral damping force.

[0057] See Figure 4 , the longitudinal damping coefficient is obtained as follows: According to the vehicle longitudinal acceleration, brake pedal stroke, accelerator pedal opening, vehicle speed, and considering the front and rear suspensions separately, a two-dimensional look-up table is performed to output the damping coefficient required for braking and the damping coefficient required for acceleration, and the maximum value of the damping coefficient required for braking and the damping coefficient required for acceleration is used as the longitudinal damping coefficient. The longitudinal damping force output control is mainly divided into acceleration damping force output control and deceleration damping force output control according to the longitudinal acceleration direction (forward is positive, backward is negative). The acceleration damping force output control is mainly based on the longitudinal acceleration a x and the throttle opening T tr and the vehicle speed V spd to calibrate the damping coefficient. As the acceleration increases, the damping coefficient increases accordingly. The deceleration damping force output control considers the output of conventional braking damping force control and emergency braking damping force control. When the vehicle is under conventional braking, according to the relationship between the longitudinal deceleration a x and the damping coefficient, the brake pedal stroke D brkpdl , the vehicle speed V spd and the relationship with the damping coefficient are calibrated so that both the front axle compression damping force and the rear suspension rebound damping force are calibrated to increase, in order to improve the vehicle body nodding movement during braking. When the vehicle longitudinal acceleration or the brake pedal stroke reaches a certain threshold and it is determined as an emergency braking, by calibrating the above parameter table, the front suspension compression damping force is further increased and the rear suspension rebound damping force is slightly reduced, in order to improve the possibility of the rear suspension tire leaving the ground and ensure the vehicle's grip.

[0058] The lateral damping coefficient is obtained as follows: According to the vehicle lateral acceleration, steering wheel angle, steering wheel angular velocity, and considering the left and right of the front and rear suspensions separately, a two-dimensional look-up table is performed to output the damping coefficient required for lateral cornering, that is, the lateral damping coefficient. It is mainly considered that the shock absorber has a greater effect on the vehicle roll angular velocity when it changes, that is, in the transient working condition, while the damping force is small in the steady state working condition, but it cannot be ignored. In these two cases, the damping force is mainly increased to improve the vehicle roll angular velocity and roll angle; but at the same time, it is necessary to consider the vehicle in the extreme state. It is recommended to reduce the damping force to reduce the left and right transfer of the axle load and improve the vehicle's extreme grip. Therefore, the lateral damping force output control is divided into lateral steady-state damping force output control, lateral transient damping force output control, and lateral extreme-state damping force output control, and the lateral damping coefficient output arbitration is performed according to the actual user scenario. The lateral steady-state damping force output control calibrates the damping coefficient according to the lateral acceleration a y ; the lateral transient damping force output control is based on the steering wheel angle Swa, the steering wheel angular velocity SwaRate and the vehicle speed Vspd Perform two-dimensional calibration of the damping coefficient; the damping force output control in the lateral limit state calibrates the damping coefficient according to the lateral acceleration.

[0059] S4. Determine the weight coefficients of the first damping force and the second damping force, and perform weighted summation on the first damping force and the second damping force to obtain the target damping force of the suspension. The target damping force F damp is calculated by the formula: F damp = F Ride ×R R + F Handing ×R H , where F Ride is the first damping force, F Handing is the second damping force, R R is the first weight coefficient, and R H is the second weight coefficient; the first weight coefficient and the second weight coefficient are pre-calibrated according to different driving modes.

[0060] See Figure 5 , according to the vehicle driving mode input, when the mode input is 1, it is the comfort mode; when the mode input is 2, it is the sport mode, when the mode input is 3, 4 is the energy-saving mode; for other mode input signals, they all enter the other mode. The above definitions of mode inputs "1, 2, 3, 4" are not fixed. In this example, only an enumeration display is made and no mandatory regulations are made. The modes can not only cover the above-listed mode types, but also develop mode types according to user needs. The present invention mainly provides a method for outputting the handling stability and ride comfort weight coefficients in different modes: according to different mode requirements, calibrate the handling stability and weight coefficients according to the vehicle speed. For example, in the comfort mode, when the vehicle speed is low, slightly degrade the damping force output for ride comfort, that is, the first damping force F Ride , and significantly degrade the damping force output for handling stability, that is, the second damping force F Handing ; when the vehicle speed is medium, maintain the output of the damping force for ride comfort, that is, the first damping force F Ride , and slightly degrade the damping force output for handling stability, that is, the second damping force F Handing ; when the vehicle speed is high, maintain the output of the damping force for ride comfort, that is, the first damping force F Ride , and maintain the output of the damping force for handling stability, that is, the second damping force F Handing , thereby forming two change curves of the weight coefficients of the first damping force F Ride and the second damping force F Handing with the vehicle speed. In the above method, the change curves of the weight coefficients of the first damping force F Ride and the second damping force F Handing with the vehicle speed can be calibrated according to the actual vehicle requirements. The present invention only enumerates and displays the calibration idea.

[0061] S5. Adjust the current of the adjustable damping shock absorber drive control unit according to the suspension target damping force obtained in S4.

[0062] In this embodiment, the maximum and minimum damping limits are output based on different road surfaces. Considering different road surfaces such as rough cement roads, smooth asphalt roads, long-wave roads, and damaged roads, the actual maximum and minimum damping forces acceptable under these road surfaces are inconsistent. Because considering the handling stability condition, it is actually insufficient to calibrate an ideal damping force corresponding to different road surfaces. Therefore, it is recommended to calibrate the acceptable maximum and minimum damping forces for different road surfaces. And limit the suspension target damping force F damp through limiting processing.

[0063] The above output suspension target damping force F damp is already available for users. However, considering safety, the damping force is amplified and output or output with a fixed current based on special conditions. It mainly involves that when the vehicle passes over a large pit or a large protrusion, the suspension may reach the compression dead point or the extreme stretching position, causing the vehicle to make a "metal-to-metal" abnormal noise, which causes discomfort to the user. Therefore, it is judged whether the vehicle is within the limit stroke range according to the height sensor signal. When a certain stroke threshold, that is, the preset stroke threshold, is reached, the correction coefficient is calibrated according to the height signal and the vehicle speed, and the correction coefficient is multiplied by the suspension target damping force obtained in S4 to obtain the final suspension target damping force. And according to the relationship between the shock absorber speed, the shock absorber damping force and the target current, the final target current, that is, the current of the adjustable damping shock absorber drive control unit, can be obtained by looking up the table.

[0064] When the vehicle receives signals such as ABS / ESC or there is a signal failure, the vehicle runs with a certain fixed current, and this current can be calibrated later. This part will not be elaborated too much. Different safety response strategies can be designed according to different requirements. Only an example is shown in the present invention and there is no mandatory requirement.

[0065] Embodiment 2. A semi-active suspension control device based on vehicle performance, which can execute the steps of the semi-active suspension control method based on vehicle performance described in the present invention, including: a vehicle state information acquisition module for acquiring vehicle state information; a vehicle driving smoothness performance calculation module for analyzing and calculating a first damping force based on the acquired vehicle state information with the aim of ensuring vehicle driving smoothness performance; a vehicle driving handling stability performance calculation module for analyzing and calculating a second damping force based on the acquired vehicle state information with the aim of ensuring vehicle driving handling stability performance; a weighted output module for performing weighted summation on the first damping force and the second damping force to obtain a suspension target damping force; and adjusting the current of the adjustable damping shock absorber drive control unit according to the obtained suspension target damping force.

[0066] This application transmits the signal after processing to the vehicle ride comfort performance calculation module and the vehicle handling stability performance calculation module. The two modules calculate the first damping force and the second damping force in parallel at the same time. The weighted output module determines the weight coefficients of handling stability and ride comfort based on the different performance requirements of different driving modes, multiplies the weight coefficients by the corresponding first damping force and second damping force, and considering that the acceptable maximum and minimum damping forces are different under different road conditions, performs damping force limiting processing. Finally, the special working condition output module outputs the final damping force based on safety considerations, whether the extreme stroke protection is triggered, and whether signals such as ABS, TCS, and ESC are received; based on the relationship diagram of suspension movement speed, damping force and current, look up the table to obtain the target current, send it to the bottom layer, control the solenoid valve drive, and realize the required damping force response to improve the vehicle driving performance.

[0067] Embodiment 3, a vehicle, including the semi-active suspension control device based on the vehicle performance of the present invention.

[0068] The above embodiments are only preferred embodiments given to fully illustrate the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or transformations made by those skilled in the art on the basis of the present invention are all within the protection scope of the present invention.

Claims

1. A semi-active suspension control method based on vehicle performance, characterized in that It includes the following steps: S1. Obtain vehicle state information; S2. Analyze and calculate the first damping force based on the obtained vehicle state information with the aim of ensuring smooth vehicle driving performance; S3. Analyze and calculate the second damping force based on the obtained vehicle state information with the aim of ensuring stable vehicle driving and handling performance; S4. Perform weighted summation on the first damping force and the second damping force to obtain the target damping force of the suspension; Suspension target damping force F damp The calculation formula is: F damp = F Ride × R R + F Handing × R H , where F Ride is the first damping force, F Handing is the second damping force, R R is the first weight coefficient, R H is the second weight coefficient; the first weight coefficient and the second weight coefficient are pre-calibrated according to different driving modes; S5. Adjust the current of the adjustable damping shock absorber drive control unit according to the target damping force of the suspension obtained in S4.

2. The semi-active suspension control method based on vehicle performance according to claim 1, wherein: The first damping force is based on at least one of the vertical vibration control of the sprung mass, the vertical vibration control of the unsprung mass, the body pitch motion control based on body pitch comfort, and the body roll motion control based on body roll comfort; The vertical vibration control based on the sprung mass is as follows: the sprung acceleration and the sprung speed in the vehicle state information are weighted and fused, then multiplied by the suspension movement speed, and finally the suspension damping coefficient C is obtained through two-dimensional look-up based on the product result and the vehicle speed. spmas ; The vertical vibration control based on the unsprung mass is as follows: the suspension damping coefficient C is obtained by performing two-dimensional look-up on the unsprung acceleration and vehicle speed in the vehicle state information w ; The vehicle body pitch motion control based on vehicle body pitch comfort is as follows: the suspension damping coefficient C is obtained by two-dimensional look-up of the vehicle pitch angular velocity and vehicle speed in the vehicle state information θ ; The body roll motion control based on body roll comfort is: obtaining the suspension damping coefficient through two-dimensional look-up of the vehicle roll angular velocity and vehicle speed in the vehicle state information The first damping force F Ride is calculated by the formula: where v def is the relative vibration speed of the unsprung mass and the sprung mass, R spmas is the weighting coefficient based on the vertical vibration control of the sprung mass, R w is the weighting coefficient based on the vertical vibration control of the unsprung mass, R θ is the weighting coefficient for the body pitch motion control based on the body pitch comfort, and is the weighting coefficient for the body roll motion control based on the body roll comfort.

3. The semi-active suspension control method based on vehicle performance according to claim 2, characterized in that The weighted fusion of the above-spring acceleration and the above-spring velocity is specifically as follows: In the formula, Z rh is the fusion vibration coefficient, k1 is the weight coefficient of the above-spring acceleration, is the above-spring acceleration, k2 is the weight coefficient of the above-spring velocity, is the above-spring velocity, v def is the relative vibration velocity of the above-spring mass and the below-spring mass.

4. The semi-active suspension control method based on vehicle performance according to claim 1 or 2, characterized in that, The second damping force F in S3 Handing has the following calculation formula: F Handing = v def × (C x × R x + C y × R y ), where v def is the relative vibration speed of the sprung mass and the unsprung mass, C x is the longitudinal damping coefficient, R x is the weight coefficient of the longitudinal damping force, C y is the lateral damping coefficient, and R y is the weight coefficient of the lateral damping force.

5. The semi-active suspension control method based on vehicle performance according to claim 4, wherein The longitudinal damping coefficient is obtained as follows: According to the vehicle longitudinal acceleration, brake pedal stroke, accelerator pedal opening, vehicle speed, and considering two-dimensional look-up tables for the front and rear suspensions separately, output the damping coefficient required for braking and the damping coefficient required for acceleration, and use the maximum value of the damping coefficient required for braking and the damping coefficient required for acceleration as the longitudinal damping coefficient; The lateral damping coefficient is obtained as follows: According to the vehicle lateral acceleration, steering wheel angle, and steering wheel angular velocity, and considering two-dimensional look-up tables for the left and right of the front and rear suspensions separately, output the damping coefficient required for lateral cornering, i.e., the lateral damping coefficient.

6. The semi-active suspension control method based on vehicle performance according to claim 1 or 2, characterized in that: Calibrate the maximum and minimum damping forces acceptable for the road surface based on different road surface conditions and vehicle speeds, and perform limiting processing on the target damping force of the suspension obtained in S4 and output it.

7. The semi-active suspension control method based on vehicle performance according to claim 1 or 2, characterized in that: Judge whether the vehicle is within the limit stroke range according to the height sensor signal. When the preset stroke threshold is reached, calibrate the correction coefficient according to the height signal and vehicle speed, and multiply the correction coefficient by the target damping force of the suspension obtained in S4 to obtain the final target damping force of the suspension.

8. A semi-active suspension control device based on vehicle performance, characterized in that, It includes: A vehicle state information acquisition module for acquiring vehicle state information; A calculation module based on vehicle driving smooth performance for analyzing and calculating the first damping force based on the obtained vehicle state information with the aim of ensuring smooth vehicle driving performance; A calculation module based on vehicle driving and handling stability performance for analyzing and calculating the second damping force based on the obtained vehicle state information with the aim of ensuring stable vehicle driving and handling performance; A weighted output module, which is used to perform weighted summation on the first damping force and the second damping force to obtain the target damping force of the suspension; the target damping force F of the suspension damp The calculation formula is: F damp = F Ride × R R + F Handing × R H , where F Ride is the first damping force, F Handing is the second damping force, R R is the first weight coefficient, R H is the second weight coefficient; the first weight coefficient and the second weight coefficient are pre-calibrated according to different driving modes; the current of the adjustable damping shock absorber drive control unit is adjusted according to the obtained target damping force of the suspension.

9. A vehicle, characterized in that: It includes the semi-active suspension control device based on the overall vehicle performance described in claim 8.

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