Multi-stage voltage adjustable electrorheological fluid damping device for vehicle suspension and control method

Abstract

The invention belongs to the technical field of suspension control, and discloses a multistage voltage adjustable electrorheological fluid damping device for a vehicle suspension and a control method. The method comprises the steps of scanning a front pavement to obtain pavement characteristic parameters, and inputting the parameters into a mode analysis model to obtain a pavement mode; at the sound wave emission moment, an ultrasonic induced electrorheological fluid pre-structure is emitted according to sound wave parameters corresponding to the pavement mode, and a corresponding pre-structure form and pre-yield stress are obtained; n-level voltage parameters and target damping force are obtained based on the pavement mode and pre-yield stress division, an N-level power source is controlled to execute the N-level voltage parameters, real-time damping force is obtained through calculation and corrected, and the damping force is corrected in real time to the target damping force through feedback adjustment; the breakthrough from passive response to active pre-judgment is achieved, electrorheological fluid pre-structuring and damping force adjustment can be completed in advance on an extreme continuous bumpy road surface, response delay is avoided, and the vibration transmissibility is remarkably reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of suspension control, and more particularly, to a multi-stage voltage-adjustable electrorheological fluid damping device for vehicle suspension and a control method. BACKGROUND

[0002] With the development of the automobile industry and the increasing demand for vehicle driving comfort and safety, the performance of vehicle suspension systems has attracted more and more attention. Traditional vehicle suspension damping control mostly uses passive suspension, which has fixed damping characteristics and is difficult to adapt to complex and changeable road conditions.

[0003] Chinese patent application No. CN108170870A discloses a design and control strategy of a shock absorber based on electrorheological materials: first step, analysis of electrorheological fluid, a. introduction of electrorheological effect and main influencing factors; b. introduction of the mechanical properties of electrorheological fluid, analysis of the role of various components in electrorheological fluid and their influence on the performance of electrorheological fluid; c. from the perspective of engineering application, the mechanical performance requirements of electrorheological fluid are proposed and analyzed, and an electrorheological fluid is prepared and corresponding mechanical performance test is carried out; second step, design of electrorheological shock absorber, a. application of fluid mechanics theory, according to the constitutive equation, the rheological equation and damping force calculation formula of electrorheological shock absorber are derived by using ring channel model and flat plate model; b. according to the mixed working mode of electrorheological fluid shock absorber, a simple structure of electrorheological fluid shock absorber is designed; c. the main structural parameters affecting the performance of the shock absorber are analyzed, and the acceleration characteristic experiment of the shock absorber is carried out on the vibration table to verify the damping effect of the shock absorber; third step, design and simulation of fuzzy control strategy of electrorheological semi-active suspension, a. the mathematical model of quarter car two-degree-of-freedom suspension and road model are established, and the suspension dynamics equation and state equation are derived; b. the fuzzy controller of automobile electrorheological semi-active suspension is designed, the dynamic model is established by using simulation software, and computer simulation is carried out; the performance indicators such as spring mass acceleration, suspension dynamic deflection and tire dynamic load are compared and analyzed with passive suspension; c. the analysis result proves that the semi-active suspension system has better damping performance than the traditional passive suspension, and also proves that the control strategy is feasible and can obviously improve the ride comfort and handling stability of the automobile. The present application realizes the continuous controllable damping force by controlling the flow characteristics of electrorheological fluid through electric field according to the characteristics of electrorheological materials with electrorheological effect, so as to realize the good ride comfort and handling stability of the vehicle.

[0004] Although the above method can meet most scenarios, research and actual application of the above method and prior art have found that the above method and prior art at least have the following defects:

[0005] The control strategy of the method relies on the real-time detection of vibration signals by vehicle state sensors, and then calculates the target damping force through an algorithm and adjusts the passive response mechanism of the electric field intensity. In extreme continuous bumping road conditions, the response speed is limited, which cannot complete the damping force adjustment within the vibration period, resulting in an increase in vibration transmission rate.

[0006] In view of this, the present application proposes a multi-stage voltage adjustable electrorheological fluid damping device for vehicle suspension and a control method to solve the above problems. SUMMARY

[0007] In order to overcome the above-mentioned defects of the prior art, in order to achieve the above-mentioned purpose, the present application provides the following technical scheme: a multi-stage voltage adjustable electrorheological fluid damping control method for vehicle suspension, comprising the following steps:

[0008] Scanning the road in front of the vehicle to obtain road characteristic parameters, including obstacle characteristics, road type and vehicle working condition;

[0009] Taking the road characteristic parameters as the input of the pattern analysis model, the road pattern is obtained;

[0010] According to the analysis of the road characteristic parameters, the sound wave emission time t is obtained, and the sound wave parameters corresponding to the road pattern are called. The ultrasonic wave corresponding to the sound wave parameters is emitted by the annular piezoelectric ultrasonic array at time t, and the electrorheological fluid is induced to form a pre-structure, and the corresponding pre-structure morphology and pre-yield stress are obtained;

[0011] Based on the road pattern and the pre-yield stress, N-stage voltage parameters and target damping force are obtained, N-stage power supply is controlled to execute N-stage voltage parameters, real-time damping force is calculated and corrected, and the real-time corrected damping force is adjusted to the target damping force through feedback.

[0012] Further, the obstacle characteristics include the height, transverse width and longitudinal distance of the obstacle; the road type includes the road type label and texture parameters; and the vehicle working condition includes the speed and vertical acceleration of the vehicle.

[0013] Further, the method for obtaining the road characteristic parameters comprises:

[0014] By emitting continuous frequency modulation waves, receiving obstacle reflection signals, and based on the difference frequency method, the longitudinal distance is calculated according to the speed of light, the difference frequency signal frequency, the frequency modulation bandwidth and the center frequency;

[0015] Collecting the obstacle image, taking the obstacle image as the input of the edge detection model, and obtaining the coordinates of the farthest vertical profile farthest point and the horizontal profile farthest point of the obstacle;

[0016] The vertical pixel difference is calculated based on the coordinates of the farthest points of the vertical profile, and the horizontal pixel difference is calculated based on the coordinates of the farthest points of the horizontal profile; the height and the lateral width of the obstacle are calculated by using a perspective projection model in combination with the longitudinal distance output by the radar, the focal length of the camera, and the pixel size;

[0017] The road surface is scanned to receive reflected light to generate road section profile data; the arithmetic average roughness is obtained by integrating and averaging the road section profile data based on the sampling length, and the arithmetic average roughness is used as the texture parameter;

[0018] The road surface type is obtained based on the texture parameter in combination with the pre-divided road surface type standard;

[0019] The driving speed is calculated in combination with the tire rolling radius based on the monitored wheel rotation speed;

[0020] The longitudinal acceleration is collected by using an acceleration sensor.

[0021] Further, the road surface modes include first single convex, second single convex, continuous gravel road, speed bump, pothole, flat asphalt road, emergency braking, and muddy road which are sequentially coded as M1-M8.

[0022] Further, the method for obtaining the corresponding pre-structure includes:

[0023] The theoretical time for the wheel to travel from the current position to the obstacle is calculated based on the longitudinal distance and the speed; the correction coefficient is calculated based on the longitudinal acceleration, the theoretical time, and the speed; the actual time is calculated based on the theoretical time and the correction coefficient, and the vehicle predicted contact time is calculated based on the current time and the actual time;

[0024] The action lead time is calculated based on the longitudinal distance and the driving speed, the sound wave emission time t is calculated based on the vehicle predicted contact time and the action lead time, the ultrasonic wave corresponding to the sound wave parameters is emitted by the ring piezoelectric ultrasonic array at the time t, the sound wave parameters include frequency, waveform, and amplitude, and the electrorheological fluid is induced to form a pre-structure;

[0025] The method for obtaining the pre-yield stress includes:

[0026] The pre-structure yield stress is calculated based on the material coefficient, the frequency, and the amplitude.

[0027] Further, the voltage parameters include center voltage, edge voltage, and voltage timing; the method for obtaining the voltage parameters includes:

[0028] The center area and the edge area are divided;

[0029] N-level graded voltages are obtained according to a geometric progression based on the critical yield voltage of the electrorheological fluid;

[0030] According to the preset mapping rule of the hierarchical voltage and the road mode, a basic voltage and a target voltage of a matching road mode are obtained;

[0031] The time window is divided by the voltage action time and the sound wave advance time, the difference between the sound wave advance arrival time and the voltage action time and the action threshold is divided into a sound field pre-structuring stage, the center area locking pre-structuring voltage is taken as the center area voltage, and the basic voltage is applied to the edge area; the difference between the voltage action time and the action threshold to the sum of the voltage action time and the second action threshold is divided into an impact response stage, and the edge area is switched to the target voltage, that is, the basic voltage is taken as the edge area voltage in the sound field pre-structuring stage, and the target voltage is taken as the edge area voltage in the impact response stage, respectively. The voltage in the sound field pre-structuring stage and the impact response stage is obtained as the voltage timing.

[0032] Further, the method for dividing the center area and the edge area comprises:

[0033] The damper piston head diameter and the reserved non-electrode area are obtained to obtain the effective electrode diameter;

[0034] The electrode area is calculated based on the effective electrode diameter, the corresponding center diameter and edge width are calculated according to the pre-division area ratio, and the center area and the edge area are divided based on the center diameter and the edge width.

[0035] Further, the method for obtaining the real-time damping force comprises:

[0036] The real-time damping force is calculated based on the pre-yield stress, the total piston area, the voltage-damping coefficient, the center area voltage, the center area, the edge area voltage and the edge area.

[0037] Further, the method for correcting the real-time damping force to the target damping force by feedback comprises:

[0038] The real-time acceleration and the target acceleration are obtained, and the acceleration difference is calculated, the edge area voltage is corrected by the PID algorithm combined with the proportional coefficient and the acceleration difference, the real-time acceleration is adjusted until the real-time correction damping force calculated based on the corrected edge area voltage is equal to the target damping force.

[0039] The multi-level voltage adjustable electrorheological fluid damping device for vehicle suspension is implemented by the multi-level voltage adjustable electrorheological fluid damping control method for vehicle suspension, comprising:

[0040] The scanning analysis module scans the road in front of the vehicle to obtain road characteristic parameters, including obstacle characteristics, road types and vehicle working conditions;

[0041] The mode analysis module takes the road characteristic parameters as the input of the mode analysis model to obtain the road mode;

[0042] Electrorheological fluid module: obtain the sound wave emission time t according to the road feature parameter analysis, call the sound wave parameters corresponding to the road mode; emit the ultrasonic wave corresponding to the sound wave parameters at time t through the ring piezoelectric ultrasonic array, induce the electrorheological fluid to form a pre-structure, and obtain the corresponding pre-structure morphology and pre-yield stress;

[0043] Damping control module: obtain N-level voltage parameters and target damping force based on the road mode and pre-yield stress division, control N-level power supply to execute N-level voltage parameters, calculate and correct real-time damping force, and adjust the real-time correction damping force to the target damping force through feedback.

[0044] The technical effects and advantages of the multi-level voltage adjustable electrorheological fluid damping device for vehicle suspension and the control method of the present application are as follows:

[0045] The present application obtains the obstacle characteristics, road type and vehicle working condition through active scanning, inputs the mode analysis model to obtain 8 kinds of road modes M1-M8 and calls the corresponding sound wave parameters, calculates the wheel expected contact time and sound wave emission time through the longitudinal distance and speed, emits the ultrasonic wave in advance through the ring piezoelectric ultrasonic array to induce the electrorheological fluid to form a pre-structure, and obtains the pre-yield stress based on the material coefficient and sound wave parameters; at the same time, the damper piston head is divided into a central region and an edge region, divided into multiple voltage levels according to the geometric progression, combined with the road mode and the pre-yield stress to match the basic voltage and the target voltage, the fixed pre-structure voltage is applied to the central region in stages, the graded voltage is dynamically applied to the edge region, and the edge region voltage is corrected based on the acceleration difference through the PID feedback algorithm, the real-time damping force is adjusted to the target value, and finally the breakthrough from passive response to active prediction is realized. The electrorheological fluid pre-structuring and damping force adjustment can be completed in advance on the extreme continuous bumping road, the response delay is avoided, the vibration transmission rate is significantly reduced, and the adaptability of the suspension in complex road conditions and the smoothness and stability of the vehicle driving are improved. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 It is a flowchart of the multi-level voltage adjustable electrorheological fluid damping control method for vehicle suspension of the present application.

[0047] Figure 2 It is a data flow diagram of embodiment 1 of the present application.

[0048] Figure 3 It is a data flow diagram of embodiment 2 of the present application.

[0049] Figure 4 It is a structural diagram of the multi-level voltage adjustable electrorheological fluid damping device for vehicle suspension of the present application. DETAILED DESCRIPTION

[0050] With reference to the accompanying drawings: the technical solutions in the embodiments of the present application will be apparently and completely described, obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor belong to the scope of protection of the present application.

[0051] Embodiment 1:

[0052] Please refer to Figure 1 、 Figure 2 , the present embodiment provides a multi-stage voltage adjustable current variable fluid damping control method for vehicle suspension, comprising:

[0053] Scanning the road surface in front of the vehicle to obtain road feature parameters, the road feature parameters including obstacle features, road types and vehicle working conditions; the obstacle features including the height, lateral width and longitudinal distance of the obstacle; the road types including road type labels and texture parameters; the vehicle working conditions including the speed and vertical acceleration of the vehicle;

[0054] The method for obtaining the road feature parameters comprises:

[0055] By emitting continuous frequency modulation waves, receiving obstacle reflection signals, and based on the light speed c, the difference frequency signal frequency f b , the frequency modulation bandwidth B and the center frequency f0, the longitudinal distance is calculated based on the difference frequency method; such as the longitudinal distance

[0056] Collecting obstacle images, taking the obstacle images as the input of the edge detection model, and obtaining the coordinates of the farthest vertical profile farthest point and the horizontal profile farthest point of the obstacle;

[0057] The training method of the edge detection model comprises:

[0058] Pre-collecting Q sets of detection training data, the detection training data including obstacle images, and the coordinates of the farthest vertical profile farthest point and the horizontal profile farthest point of the obstacle.

[0059] Taking the detection training data as the input of the edge detection model, taking the coordinates of the farthest vertical profile farthest point and the horizontal profile farthest point of the obstacle as the output of the edge detection model, taking the error minimization between the output coordinates of the farthest vertical profile farthest point and the horizontal profile farthest point of the obstacle and the actual coordinates of the farthest vertical profile farthest point and the horizontal profile farthest point of the obstacle as the target, optimizing the network parameters of the edge detection model through the natural heuristic optimization algorithm, obtaining the network parameters corresponding to the minimum loss function of the double error directional optimization of the edge detection model, and constructing the edge detection model corresponding to the network parameters as the trained edge detection model.

[0060] Based on the vertical profile farthest point coordinate calculation, the vertical pixel difference Δy is obtained, and based on the horizontal profile farthest point coordinate calculation, the horizontal pixel difference Δx is obtained; combined with the longitudinal distance d output by the radar, the camera focal length f and the pixel size k, the height and transverse width of the obstacle are calculated by using the perspective projection model; such as the height and the transverse width

[0061] Scan the road surface, receive reflected light to generate road section profile data; based on the sampling length, the road section profile data is integrated and averaged to obtain the arithmetic average roughness, and the arithmetic average roughness is taken as the texture parameter;

[0062] Based on the texture parameter combined with the pre-divided road type standard, the road type is obtained; such as the road type including the road surface with texture parameter lower than 20 μm is divided into flat road surface, such as asphalt road surface, the road surface with texture parameter not lower than 20 μm and lower than 50 μm is divided into medium rough road surface, such as cement road surface, and the road surface with texture parameter not lower than 50 μm is divided into high rough road surface, such as gravel road and pothole road;

[0063] Monitor the wheel speed, and combined with the tire rolling radius, the driving speed is calculated and obtained;

[0064] The longitudinal acceleration is collected and obtained by the acceleration sensor.

[0065] The above method can obtain the size and distance of the obstacle, the roughness of the road surface and the running state of the vehicle itself and other key information in advance before the vehicle contacts the road obstacle or enters the specific road condition, breaking the passive response mechanism of the existing control strategy which relies on the real-time detection of vibration signals by vehicle state sensors, so that the system can predict the road impact based on the parameters obtained in advance, and in the extreme continuous bumpy road scene, the damping force adjustment can be planned according to the obstacle characteristics, road type and vehicle working condition before the vibration occurs, avoiding the problem that the adjustment cannot be completed within the vibration period due to the limitation of response speed, thereby effectively reducing the vibration transmission rate.

[0066] The road feature parameters are taken as the input of the pattern analysis model to obtain the road pattern; the road pattern includes first single convex, second single convex, continuous gravel road, speed bump, pothole, flat asphalt road, emergency braking and muddy road, which are encoded as M1-M8 in turn;

[0067] The training method of the pattern analysis model includes:

[0068] Pre-collect Q groups of pattern training data, and the training data includes road feature parameters and road pattern.

[0069] The mode training data is taken as the input of the mode analysis model, and the road surface mode is taken as the output of the mode analysis model, so as to minimize the error between the output road surface mode and the actual road surface mode, and the network parameters of the mode analysis model are optimized through the natural heuristic optimization algorithm, so as to obtain the network parameters corresponding to the minimum loss function of the double-error directional optimization of the mode analysis model, and the mode analysis model constructed by the corresponding network parameters is taken as the trained mode analysis model.

[0070] The above method can realize accurate identification and classification of different road conditions based on the road surface information obtained in advance, and then match the targeted sound wave action scheme, changing the passive response mode of the existing control strategy which relies on real-time vibration signal detection; by determining the road surface mode in advance and calling the adaptive sound wave parameters, the system can start the sound wave to pre-structure the electrorheological fluid before the vibration occurs when the vehicle encounters extreme continuous bumping road surface, avoiding the problem that the damping force adjustment cannot be completed within the vibration period due to the response speed limitation, thereby effectively reducing the vibration transmission rate.

[0071] According to the analysis of the road feature parameters, the sound wave emission time t is obtained, and the sound wave parameters corresponding to the road surface mode are called; the annular piezoelectric ultrasonic array emits ultrasonic waves corresponding to the sound wave parameters at time t, and the sound wave parameters include frequency, waveform and amplitude; the electrorheological fluid is induced to form a pre-structure, and the corresponding pre-structure morphology and pre-yield stress are obtained;

[0072] The method for obtaining the corresponding pre-structure includes:

[0073] The theoretical time t that the wheel travels from the current position to the obstacle is obtained based on the longitudinal distance and the speed ll ; the correction coefficient is obtained based on the longitudinal acceleration a, the theoretical time t ll and the speed v; for example, the correction coefficient k The actual time is obtained based on the theoretical time t ll and the correction coefficient, for example, the actual time t sj =t ll ×k a , the vehicle predicted contact time is obtained based on the current time and the actual time;

[0074] The action advance amount is obtained based on the longitudinal distance and the driving speed, the sound wave emission time t is obtained based on the vehicle predicted contact time and the action advance amount, and the annular piezoelectric ultrasonic array emits ultrasonic waves at time t, and the electrorheological fluid is induced to form a pre-structure.

[0075] The method realizes the advanced pretreatment of the electrorheological fluid, changes the passive response mode of the existing control strategy which relies on real-time detection of the vibration signal, and makes the system complete the structural preparation required for damping force adjustment before the vibration occurs on the extreme continuous jounce road surface, thereby avoiding the problem that the adjustment cannot be completed within the vibration period due to the response speed limitation, and effectively reducing the vibration transmission rate.

[0076] The method for obtaining the pre-yield stress comprises:

[0077] The pre-yield stress is calculated and obtained according to the material coefficient, the frequency and the amplitude.

[0078] The method can quantify the initial strength of the electrorheological fluid after the sound wave pretreatment, and provide accurate basic parameters for subsequent damping force adjustment; by determining the pre-yield stress in advance, the system can plan a voltage adjustment strategy based on the stress before the vehicle contacts the road obstacle, thereby avoiding the adjustment delay caused by real-time detection and calculation time in the existing passive response mechanism, so that the damping force can quickly reach the target value within the vibration period on the extreme continuous jounce road surface, thereby effectively reducing the vibration transmission rate.

[0079] The N-level voltage parameters and the target damping force are obtained based on the road mode and the pre-yield stress, the N-level power supply is controlled to execute the N-level voltage parameters, the real-time damping force is calculated and obtained, and the real-time damping force is corrected to the target damping force through feedback adjustment.

[0080] The voltage parameters include a center region voltage, an edge region voltage and a voltage timing; and the method for obtaining the voltage parameters comprises:

[0081] The center region and the edge region are divided.

[0082] The method for dividing the center region and the edge region comprises:

[0083] The diameter D of the damper piston head is obtained h , and the non-electrode area D yl is reserved to obtain the effective electrode diameter; for example, the effective electrode diameter D = D h -2×D yl .

[0084] The electrode area is calculated and obtained based on the effective electrode diameter, for example, the electrode area A = πD

[0085] The corresponding center diameter and edge width are calculated and obtained according to the pre-divided area ratio, and the center region and the edge region are divided based on the center diameter and the edge width.

[0086] The critical yield voltage U of the electrorheological fluid is obtained 临界, according to the geometric progression division to obtain N level grading voltage; such as the k level voltage U k = U 临界 × r k-1 , k = 1, 2,..., N-1, wherein, r is the common ratio, generally take 1.2-1.5; the no-load voltage U0=0; N is the voltage grading number, generally take 3≤N<6;

[0087] According to the preset mapping rule of the grading voltage and the road surface mode, the basic voltage and the target voltage of the matching road surface mode are obtained; wherein, the basic voltage is the voltage of the edge area in the sound field pre-structuring stage, and the target voltage is the voltage of the edge area in the impact response stage; such as each road surface mode corresponds to a unique basic voltage and target voltage, and is positively correlated with the impact intensity of the mode;

[0088] The voltage action time and the sound wave advance time are used to divide the time window, the difference between the sound wave advance arrival time and the voltage action time and the action threshold value is divided into the sound field pre-structuring stage, the center area locks the pre-structure voltage as the center area voltage, and the basic voltage is applied to the edge area; the difference between the voltage action time and the action threshold value and the sum of the voltage action time and the second action threshold value are divided into the impact response stage, and the edge area is switched to the target voltage, that is, the basic voltage is used as the edge area voltage in the sound field pre-structuring stage, and the target voltage is used as the edge area voltage in the impact response stage, and the voltage in the sound field pre-structuring stage and the impact response stage is obtained respectively as the voltage time sequence.

[0089] The above method obtains the electrode effective diameter by obtaining the damper piston head diameter and reserving the non-electrode area, calculates the electrode area based on the electrode effective diameter, determines the center diameter and the edge width according to the pre-division area proportion to divide the center area and the edge area, obtains the critical yield voltage of the electrorheological fluid, divides N level grading voltage according to the geometric progression, and according to the preset mapping rule of the grading voltage and the road surface mode, the voltage action time and the sound wave advance time are used to divide the sound field pre-structuring stage and the impact response stage, and then N level voltage parameters and target damping force are obtained based on the road surface mode and the pre-yield stress, the N level power supply is controlled to execute the voltage parameters, and the real-time damping force is corrected to the target damping force through feedback adjustment, which builds an active adjustment system from structure partitioning to voltage grading, from mode matching to time sequence control, breaks the passive response mechanism relying on real-time vibration signal detection; through the advance division of the area and the grading voltage, the voltage parameters are matched and applied in stages, and the real-time feedback correction is matched, so that the system can quickly complete the damping force adjustment in the vibration cycle on the extreme continuous jolt road surface, and the adjustment lag caused by the response speed limitation is avoided, thereby effectively reducing the vibration transmission rate.

[0090] The method for obtaining the real-time damping force comprises:

[0091] Based on the pre-yield stress τ0, the total area of the piston S, the voltage-damping coefficient k F , the center area voltage U 中心 , the center area S c , the edge area voltage U 边缘 , and the edge area S e The real-time damping force is calculated as F = τ0·S + k F ·(U 中心 ·S c + U 边缘 ·S e ).

[0092] The above method can integrate the basic strength of the electrorheological fluid pre-structure and the additional strength of the partition voltage effect, and accurately quantify the current damping force. By calculating and mastering the damping force in real time, the system can quickly trigger feedback adjustment based on the deviation of the real-time value and the target damping force when the vehicle encounters extreme continuous bumping road, avoiding the adjustment delay caused by relying on the lag of the vibration signal detection in the existing passive response mechanism, ensuring that the damping force can be corrected to the target value in the vibration period, thereby effectively reducing the vibration transmission rate.

[0093] The method of feedback correction of real-time damping force to target damping force includes:

[0094] The real-time acceleration and target acceleration are obtained, and the acceleration difference is calculated. The edge area voltage is corrected by the PID algorithm combined with the proportional coefficient and the acceleration difference to adjust the real-time acceleration until the real-time correction damping force calculated based on the corrected edge area voltage is equal to the target damping force.

[0095] The above method obtains the real-time acceleration and target acceleration and calculates the acceleration difference. The edge area voltage is corrected by the PID algorithm combined with the proportional coefficient to adjust the real-time acceleration until the real-time correction damping force calculated based on the corrected edge area voltage is equal to the target damping force. This method establishes a closed-loop feedback adjustment mechanism that can track the damping force deviation in real time and respond quickly. Compared with the existing passive response that relies on vibration signal detection, this mechanism can complete damping force correction within the vibration period of extreme continuous bumping road through the immediate calculation of the acceleration difference and the rapid adjustment of the PID algorithm, avoiding the adjustment lag caused by the limited response speed, thereby effectively reducing the vibration transmission rate.

[0096] Embodiment 2:

[0097] Please refer to Figure 3 , the present embodiment provides a predictive damping force feedforward-feedback composite control method applied to embodiment 1, including the following steps:

[0098] Obtain the road feature parameters and acceleration in the past T0 period as the input of the prediction model, and obtain the target damping force f in the future T1 period 预 , combined with the target damping force F 预 in the future T1 period 实 Calculate the total control voltage, such as total control voltage U 总 =k1·(F 预 -F 实 )+k2·∫(F 预 -F 实 )dt, wherein k1 is the feedforward control gain, which determines the immediate adjustment strength of the predicted damping force deviation; k2 is the feedback integral gain, which eliminates long-term cumulative deviation; k1 and k2 can be obtained by testing according to the control variable method on the standard bump road at a fixed speed; adjust the edge area voltage according to the total control voltage, wherein the center area voltage is the pre-structure voltage, and the edge area voltage is the difference between the total control voltage and the pre-structure voltage.

[0099] The above method predicts the target damping force in the future T1 period through the LSTM network, upgrades the control logic from the current state correction to the future state planning, and fundamentally shortens the time difference between damping force adjustment and vibration impact. This "prediction-execution" mode is not a parameter optimization of the existing feedback algorithm, but introduces a new feedforward control dimension, so that the system has completed the adjustment preparation before the vibration occurs, and the adaptability to the continuous bump road is improved in quality.

[0100] Embodiment 3:

[0101] Please refer to Figure 4 , the embodiment provides a multi-stage voltage adjustable electrorheological fluid damping device for vehicle suspension, which comprises:

[0102] Scan analysis module: scan the road ahead of the vehicle to obtain road feature parameters, including obstacle features, road types and vehicle working conditions;

[0103] Mode analysis module: input the road feature parameters into the mode analysis model to obtain the road mode;

[0104] Electrorheological fluid module: obtain the sound wave emission time t according to the road feature parameter analysis, call the sound wave parameters corresponding to the road mode; emit the ultrasonic wave corresponding to the sound wave parameters at time t through the ring piezoelectric ultrasonic array, induce the electrorheological fluid to form a pre-structure, and obtain the corresponding pre-structure morphology and pre-yield stress;

[0105] The damping control module: based on the road mode and the pre-yield stress division obtains N-stage voltage parameters and target damping force, controls N-stage power supply to execute N-stage voltage parameters, calculates to obtain real-time damping force, and carries out correction, and adjusts the real-time correction damping force to the target damping force through feedback.

[0106] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

[0107] Finally: the above is only a preferred embodiment of the present application and is not used to limit the present application, any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included within the protection scope of the present application.

Claims

1. A multi-level voltage adjustable electrorheological fluid damping control method for vehicle suspension, characterized in that: The steps include: Scan the road ahead of the vehicle to obtain road characteristic parameters, which include obstacle characteristics, road type, and vehicle operating conditions; The pavement characteristic parameters are used as inputs of the pattern analysis model to obtain the pavement pattern; The acoustic wave emission time t is obtained based on the analysis of road surface characteristic parameters, and the acoustic wave parameters corresponding to the road surface pattern are called. The ultrasonic wave corresponding to the acoustic wave parameters is emitted at time t through the annular piezoelectric ultrasonic array to induce the electrorheological fluid to form a pre-structure, and the corresponding pre-structure morphology and pre-yield stress are obtained. Based on the road surface pattern and pre-yield stress division, N-level voltage parameters and target damping force are obtained, the N-level power supply is controlled to execute the N-level voltage parameters, the real-time damping force is calculated and corrected, and the real-time corrected damping force is adjusted to the target damping force through feedback.

2. The multi-level voltage adjustable electrorheological fluid damping control method for vehicle suspension according to claim 1, characterized in that: Obstacle features include obstacle height, lateral width, and longitudinal distance; road surface type includes road surface type label and texture parameters; vehicle operating conditions include vehicle speed and vertical acceleration.

3. The multi-level voltage adjustable electrorheological fluid damping control method for vehicle suspension according to claim 2, characterized in that: Methods for obtaining road surface characteristic parameters include: By transmitting continuous frequency modulation waves and receiving the reflected signals from obstacles, the longitudinal distance is calculated based on the difference frequency method according to the speed of light, the frequency of the difference frequency signal, the frequency modulation bandwidth and the center frequency. Collect obstacle images and use them as input to the edge detection model to obtain the coordinates of the farthest point of the obstacle's vertical contour and the farthest point of the horizontal contour; The vertical pixel difference is calculated based on the coordinates of the farthest point of the vertical profile, and the horizontal pixel difference is calculated based on the coordinates of the farthest point of the horizontal profile. The height and horizontal width of the obstacle are calculated using the perspective projection model, combining the longitudinal distance output by the radar, the camera focal length and pixel size. Scan the road surface, receive reflected light and generate road surface cross-sectional profile data; integrate and average the road surface cross-sectional profile data based on the sampling length to obtain the arithmetic mean roughness, and use the arithmetic mean roughness as a texture parameter; Obtaining the road surface type based on texture parameters combined with pre-divided road surface type standards; Monitor wheel speed and calculate driving speed based on tire rolling radius; The longitudinal acceleration is acquired by the acceleration sensor.

4. The multi-level voltage adjustable electrorheological fluid damping control method for vehicle suspension according to claim 1, characterized in that: The road surface patterns include a first single bump, a second single bump, a continuous gravel road, a speed bump, a pothole, a smooth asphalt road, an emergency brake, and a muddy road, which are sequentially coded as M1-M8.

5. The multi-level voltage adjustable electrorheological fluid damping control method for vehicle suspension according to claim 1, characterized in that: Methods for obtaining the corresponding pre-structure include: The theoretical time it takes for the wheel to travel from its current position to the obstacle is calculated based on the longitudinal distance and speed. A correction factor is calculated based on the longitudinal acceleration, theoretical time, and speed. The actual time is calculated based on the theoretical time and correction factor, and the estimated contact time of the vehicle is calculated based on the current time and actual time. The action lead is calculated based on the longitudinal distance and the driving speed. The acoustic wave emission time t is calculated based on the estimated vehicle contact time and the action lead. The annular piezoelectric ultrasonic array emits an ultrasonic wave corresponding to the acoustic wave parameters at time t. The acoustic wave parameters include frequency, waveform, and amplitude, inducing the electrorheological fluid to form a pre-structure. Methods for obtaining pre-yield stress include: The pre-structure yield stress is calculated based on the material coefficient, frequency and amplitude.

6. The multi-level voltage adjustable electrorheological fluid damping control method for vehicle suspension according to claim 1, characterized in that: The voltage parameters include center voltage, edge voltage and voltage timing; Methods for obtaining voltage parameters include: Divide the central area into peripheral areas; Based on the critical yield voltage of the electrorheological fluid, N-level voltage grading is obtained according to geometric progression. Obtaining a base voltage and a target voltage matching the road surface pattern according to a preset mapping rule between the graded voltage and the road surface pattern; The voltage action time and the sound wave advance time are obtained to divide the time window, and the difference from the sound wave advance arrival time to the voltage action time and the action threshold is divided into the sound field pre-structuring stage, the central area locks the pre-structuring voltage as the central area voltage, and the basic voltage is applied to the edge area; the difference from the voltage action time and the action threshold to the sum of the voltage action time and the second action threshold is divided into the impulse response stage, and the edge area is switched to the target voltage, that is, the basic voltage is used as the edge area voltage in the sound field pre-structuring stage, and the target voltage is used as the edge area voltage in the impulse response stage, and the voltages in the sound field pre-structuring stage and the impulse response stage are respectively obtained as voltage time series.

7. The multi-level voltage adjustable electrorheological fluid damping control method for vehicle suspension according to claim 6, characterized in that: Methods for dividing the central area and the peripheral area include: Obtain the damper piston head diameter and the reserved non-electrode area to obtain the effective electrode diameter; The electrode area is calculated based on the effective diameter of the electrode, the corresponding center diameter and edge width are calculated according to the pre-divided area ratio, and the center area and edge area are obtained based on the center diameter and edge width.

8. The multi-level voltage adjustable electrorheological fluid damping control method for vehicle suspension according to claim 1, characterized in that: Methods for obtaining real-time damping force include: The real-time damping force is calculated based on the pre-yield stress, the total piston area, the voltage-damping coefficient, the center area voltage, the center area, the edge area voltage, and the edge area.

9. The multi-level voltage adjustable electrorheological fluid damping control method for vehicle suspension according to claim 1, characterized in that: Methods for correcting the real-time damping force to the target damping force through feedback include: The real-time acceleration and target acceleration are obtained, and the acceleration difference is calculated. The edge area voltage is corrected using the PID algorithm, combining the proportional coefficient and the acceleration difference, and the real-time acceleration is adjusted until the real-time corrected damping force calculated based on the corrected edge area voltage is equal to the target damping force.

10. A multi-level voltage adjustable electrorheological fluid damping device for a vehicle suspension, implementing the multi-level voltage adjustable electrorheological fluid damping control method for a vehicle suspension according to any one of claims 1 to 9, characterized in that: include: Scanning and analysis module: scans the road ahead of the vehicle to obtain road characteristic parameters, which include obstacle characteristics, road type, and vehicle operating conditions; Pattern analysis module: takes the pavement characteristic parameters as input to the pattern analysis model to obtain the pavement pattern; The electrorheological fluid module obtains the acoustic wave emission time t based on the road surface characteristic parameter analysis and calls the acoustic wave parameters corresponding to the road surface pattern. The annular piezoelectric ultrasonic array emits ultrasonic waves corresponding to the acoustic wave parameters at time t, inducing the electrorheological fluid to form a pre-structure and obtain the corresponding pre-structure morphology and pre-yield stress. Damping control module: Based on the road surface pattern and pre-yield stress division, N-level voltage parameters and target damping force are obtained, N-level power supplies are controlled to execute N-level voltage parameters, real-time damping force is calculated and corrected, and the real-time correction damping force is adjusted to the target damping force through feedback.

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