Vehicle semi-active suspension damping control method, device, equipment and medium

Abstract

The application discloses a vehicle semi-active suspension damping control method, device, equipment and medium, relates to the technical field of vehicle control, and comprises the following steps: establishing a multi-degree-of-freedom whole vehicle dynamics model based on the motion posture of a vehicle and in combination with the influence of each motion posture on the smoothness of the vehicle; calculating a whole vehicle vibration equation according to the established degree-of-freedom whole vehicle dynamics model, and calculating a variable damping output value according to a semi-active suspension damping force output control logic; adjusting PID parameters based on a preset intelligent algorithm, and realizing variable damping output control through a PID controller after parameter adjustment. The application can effectively solve the full-frequency adaptive correction of the semi-active suspension control strategy and ensure the body posture stability.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, specifically to a method, device, equipment, and medium for semi-active suspension damping control of a vehicle. Background Technology

[0002] The performance of a car's suspension system directly affects its ride comfort and handling safety. Traditional passive suspensions have fixed parameters and therefore less than ideal performance. While active suspensions offer better performance, they consume excessive energy and have not been widely adopted. In recent years, semi-active suspensions have shown promising prospects because they require less energy and their performance is close to that of active suspensions.

[0003] Semi-active suspension refers to a controllable suspension system that uses sensors to sense road conditions and vehicle posture, adjusting damping parameters to improve ride comfort and stability. Semi-active suspension can achieve full-frequency control optimization of both active and passive suspension systems and is currently widely used in various vehicle models.

[0004] Currently, semi-active suspension control strategies often employ classic algorithms, while also specifying the suspension system and controlling a single target. This results in limited applicability to specific operating conditions and an inability to simultaneously address both low-frequency and high-frequency conditions. Therefore, improving the comprehensive applicability of semi-active suspension damping control to ensure vehicle body stability is a pressing issue that needs to be addressed. Summary of the Invention

[0005] This application provides a method, device, equipment, and medium for semi-active suspension damping control of a vehicle, which can effectively solve the full-frequency adaptive correction of the semi-active suspension control strategy and ensure the stability of the vehicle body posture.

[0006] In a first aspect, embodiments of this application provide a semi-active vehicle suspension damping control method, the semi-active vehicle suspension damping control method comprising:

[0007] Based on the vehicle's motion posture and the influence of each motion posture on the vehicle's ride comfort, a multi-degree-of-freedom vehicle dynamics model is established.

[0008] Based on the established vehicle dynamics model with degrees of freedom, the vehicle vibration equation is calculated, and the variable damping output value is calculated based on the semi-active suspension damping force output control logic.

[0009] The PID parameters are adjusted based on a preset intelligent algorithm, and the variable damping output control is achieved through the PID controller after parameter adjustment.

[0010] In conjunction with the first aspect, in one implementation, the establishment of a multi-degree-of-freedom vehicle dynamics model based on the vehicle's motion posture and considering the influence of each motion posture on vehicle ride comfort specifically involves:

[0011] The vehicle body is set as a rigid body with concentrated mass, and only the effects of vertical, roll and pitch motions on vehicle ride comfort are considered.

[0012] Assume the vehicle is symmetrical about the longitudinal centerline and moves at a constant speed in a straight line. Assume the road surface is a stable, normally distributed random process with all states ergodic, and establish a seven-degree-of-freedom vehicle dynamics model.

[0013] In conjunction with the first aspect, in one implementation, the vehicle vibration equation is specifically as follows:

[0014]

[0015] Where M represents the vehicle's mass matrix, C represents the vehicle's damping matrix, K represents the vehicle's stiffness matrix, and Z represents the displacement vectors of each degree of freedom of the vehicle. The first derivative of the displacement vector for each degree of freedom of the vehicle. K represents the second derivative of the displacement vector of each degree of freedom of the vehicle. t Let C represent the tire stiffness matrix, Q represent the road surface input vector (i.e., the road surface roughness), and C represent the road surface roughness matrix. t Let F represent the tire damping matrix and F represent the vehicle stiffness matrix.

[0016] The vehicle's stiffness matrix is ​​as follows:

[0017]

[0018] Where a represents the distance from the front axle to the vehicle's center of gravity, b represents the distance from the rear axle to the vehicle's center of gravity, c represents the distance from the right tire's contact point to the vehicle's center of gravity, d represents the distance from the left tire's contact point to the vehicle's center of gravity, k1 represents the stiffness of the left front tire, k2 represents the stiffness of the left front suspension, k3 represents the stiffness of the right front tire, k4 represents the stiffness of the right front suspension, k5 represents the stiffness of the left rear tire, k6 represents the stiffness of the left rear suspension, k7 represents the stiffness of the right rear tire, k8 represents the stiffness of the right rear suspension, and L represents the track width between the left and right wheels.

[0019] Specifically, the vehicle's damping matrix is ​​as follows:

[0020]

[0021] Wherein, C1 represents the equivalent damping coefficient of the left front tire, C2 represents the equivalent damping coefficient of the left front passive suspension, C3 represents the equivalent damping coefficient of the right front tire, C4 represents the equivalent damping coefficient of the right front passive suspension, C5 represents the equivalent damping coefficient of the left rear tire, C6 represents the equivalent damping coefficient of the left rear passive suspension, C7 represents the equivalent damping coefficient of the right rear tire, and C8 represents the equivalent damping coefficient of the right rear passive suspension.

[0022] In conjunction with the first aspect, in one implementation, the step of calculating the variable damping output value based on the semi-active suspension damping force output control logic specifically involves:

[0023] Based on the vehicle vibration equation, the semi-active suspension damping force output control logic is determined to obtain the adjustable damping output damping force of each shock absorber and the relative motion speed of each shock absorber.

[0024] Based on the relative motion velocities of each shock absorber, the variable damping output value is determined by optimizing the target method.

[0025] In conjunction with the first aspect, in one implementation method,

[0026] The semi-active suspension damping force output control logic is determined to obtain the adjustable damping output damping force of each shock absorber and the relative motion velocity of each shock absorber. Specifically, the calculation method for the adjustable damping output damping force of each shock absorber is as follows:

[0027]

[0028]

[0029]

[0030]

[0031] Where F1 represents the adjustable damping output force of the left front shock absorber, F2 represents the adjustable damping output force of the right front shock absorber, F3 represents the adjustable damping output force of the left rear shock absorber, F4 represents the adjustable damping output force of the right rear shock absorber, and c1 max c2 indicates the maximum adjustable damping of the left front suspension. max This indicates the maximum adjustable damping of the right front suspension, c3. max This indicates the maximum adjustable damping of the left rear suspension, c4 max c1 represents the maximum adjustable damping of the right rear suspension. mex c2 represents the actual output damping of the variable damping system on the left front suspension. mex This indicates the actual output damping of the right front suspension variable damping, c3. mex c4 indicates the actual output damping of the left rear suspension variable damping. mexThis indicates the actual output damping of the right rear suspension variable damping. This indicates the relative speed of the left front shock absorber. This indicates the relative speed of the right front shock absorber. This indicates the relative velocity of the left rear shock absorber. This indicates the relative velocity of the right rear shock absorber. This represents the first derivative of the vertical displacement at the connection point between the suspension and the front left side of the vehicle body. This represents the first derivative of the vertical displacement at the connection point between the suspension and the front right side of the vehicle body. This represents the first derivative of the vertical displacement at the connection point between the suspension and the left rear of the vehicle body. This represents the first derivative of the vertical displacement at the connection point between the suspension and the right rear of the vehicle body. This represents the first derivative of the vertical displacement of the left front wheel. This represents the first derivative of the vertical displacement of the right front wheel. This represents the first derivative of the vertical displacement of the left rear wheel. This represents the first derivative of the vertical displacement of the right rear wheel.

[0032] The semi-active suspension damping force output control logic is determined to obtain the adjustable damping output damping force of each shock absorber and the relative motion speed of each shock absorber. The specific calculation method for the relative motion speed of each shock absorber is as follows:

[0033] z bw1 =z1-z 5lf

[0034] z bw2 =z2-z 5rf

[0035] z bw3 =z3-z 5lr

[0036] z bw4 =z4-z 5lr

[0037] Among them, z bw1 The z represents the relative displacement of the left front shock absorber. bw2 The z-axis represents the relative displacement of the right front shock absorber. bw3 The z-axis represents the relative displacement of the left rear shock absorber. bw4 The values ​​represent the relative displacement of the right rear shock absorber, z1 represents the vertical displacement of the left front wheel, z2 represents the vertical displacement of the right front wheel, z3 represents the vertical displacement of the left rear wheel, and z4 represents the vertical displacement of the right rear wheel. 5lf This indicates the vertical displacement at the connection point between the suspension and the front left side of the vehicle body, z. 5rfThis indicates the vertical displacement at the connection point between the suspension and the front right side of the vehicle body, z. 5lr This indicates the vertical displacement at the connection point between the suspension and the left rear of the vehicle body, z. 5lr This indicates the vertical displacement at the connection point between the suspension and the right rear of the vehicle body;

[0038] Specifically, the calculation method for the vertical displacement at the connection point between the suspension and the vehicle body is as follows:

[0039] z 5lf =z5+a·z7-d·z6

[0040] z 5rf = z5 + a·z7 + c·z6

[0041] z 5lr =z5-b·z7-d·z6

[0042] z 5rr =z5-b·z7+c·z6

[0043] Where z5 represents the vertical displacement of the vehicle's center of gravity, z6 represents the roll angle displacement of the vehicle, z7 represents the pitch angle displacement of the vehicle, a represents the distance from the front axle to the vehicle's center of gravity, b represents the distance from the rear axle to the vehicle's center of gravity, c represents the distance from the right tire contact point to the vehicle's center of gravity, and d represents the distance from the left tire contact point to the vehicle's center of gravity.

[0044] In conjunction with the first aspect, in one implementation, determining the variable damping output value based on the obtained relative motion velocities of each shock absorber through an optimized target method specifically involves:

[0045] When any of the relative motion speeds of the left front shock absorber, right front shock absorber, left rear shock absorber, and right rear shock absorber are less than 0, the optimization target mode is executed to determine the variable damping output value.

[0046] Based on the changes in vehicle pitch and roll, as well as the relative movement of the vehicle's suspension connection points, the damping output can be continuously and steplessly adjusted.

[0047] The optimization objective method is specifically as follows:

[0048]

[0049] Where J represents the variable damping output value, and sqr represents the square root. The second derivative of the vertical displacement of the vehicle's center of mass is given. The second derivative of the roll angle displacement of the vehicle body is given. The second derivative of the pitch angle displacement of the vehicle body is given.

[0050] In conjunction with the first aspect, in one implementation, adjusting the PID parameters based on a preset intelligent algorithm specifically involves:

[0051] Perform parameter initialization and randomly generate an initial population. Specifically:

[0052] X = {x1, x2, ..., x} n} T

[0053] Where X represents the initial population, x n Let T represent a sparrow, and let T represent the matrix transpose.

[0054] Execute the search algorithm:

[0055]

[0056] in, Let α represent the j-th dimension position information of the i-th sparrow in the t-th iteration, exp represent the exponential function with base e, and α represent the position of the i-th sparrow in the t-th iteration. t T represents a random number, with values ​​ranging from [0,1]. max R2 represents the maximum number of iterations, R2 represents the warning value, which is a random number between [0,1], ST represents the safety threshold, which is a constant between [0.5,1], q represents a random number that follows a normal distribution, L represents a 1×d dimensional matrix of all 1s, and d represents a positive integer;

[0057] Update joiner positions:

[0058]

[0059] in, Let represent the worst individual in the t-th iteration, and n represent the total number of sparrows. This indicates the position of the optimal discoverer in the (t+1)th iteration;

[0060] Update: Aware of the danger:

[0061]

[0062] in, Let f represent the optimal individual in the t-th iteration, β represent a random number that follows a normal distribution with a mean of 0 and a variance of 1, and f i f represents the current fitness value of an individual. g This represents the current maximum fitness value, k represents a random number with a value of [-1, 1], the sign indicates the direction of the sparrow's movement, the size represents the step size control parameter, ε represents a constant, and f w This represents the current minimum fitness value;

[0063] Based on the calculation method of updating the awareness of danger, it is determined whether the stopping condition is met. If so, the optimal sparrow position is output. If not, the search algorithm is executed again, and the position of the joiner and the awareness of danger are updated. This process is repeated until the stopping condition is met.

[0064] Secondly, embodiments of this application provide a vehicle semi-active suspension damping control device, the vehicle semi-active suspension damping control device comprising:

[0065] Create a module that is used to establish a multi-degree-of-freedom vehicle dynamics model based on the vehicle's motion posture and the influence of each motion posture on the vehicle's ride comfort.

[0066] The calculation module is used to calculate the vehicle vibration equation based on the established vehicle dynamics model with degrees of freedom, and to calculate the variable damping output value based on the semi-active suspension damping force output control logic.

[0067] The control module is used to adjust the PID parameters based on a preset intelligent algorithm, and to achieve variable damping output control through the PID controller after parameter adjustment.

[0068] Thirdly, embodiments of this application provide a vehicle semi-active suspension damping control device, the vehicle semi-active suspension damping control device including a processor, a memory, and a vehicle semi-active suspension damping control program stored in the memory and executable by the processor, wherein when the vehicle semi-active suspension damping control program is executed by the processor, the steps of the vehicle semi-active suspension damping control method described above are implemented.

[0069] Fourthly, embodiments of this application provide a computer-readable storage medium, characterized in that the computer-readable storage medium stores a vehicle semi-active suspension damping control program, wherein when the vehicle semi-active suspension damping control program is executed by a processor, it implements the steps of the vehicle semi-active suspension damping control method described above.

[0070] The beneficial effects of the technical solutions provided in this application include:

[0071] (1) By establishing a multi-degree-of-freedom vehicle dynamics model based on the vehicle's motion posture and the influence of each motion posture on the vehicle's ride comfort, the vehicle vibration equation is calculated based on the established multi-degree-of-freedom vehicle dynamics model. The variable damping output value is calculated based on the semi-active suspension damping force output control logic. The PID parameters are then adjusted based on a preset intelligent algorithm, and the variable damping output control is achieved through the PID controller after parameter adjustment. This effectively solves the full-band adaptive correction of the semi-active suspension control strategy and ensures the stability of the vehicle body posture.

[0072] (2) By establishing a seven-degree-of-freedom vehicle dynamics model, including a semi-active suspension output damping force control strategy, an improved control algorithm is adopted, and intelligent algorithms are integrated to adjust PID parameters, avoiding human interference and achieving a significant improvement in algorithm efficiency and robustness. Attached Figure Description

[0073] Figure 1 This is a flowchart illustrating the semi-active suspension damping control method for vehicles described in this application.

[0074] Figure 2 A schematic diagram of the established seven-degree-of-freedom vehicle dynamics model;

[0075] Figure 3 This is a schematic diagram of the functional modules of the semi-active suspension damping control device for the vehicle in this application.

[0076] Figure 4 This is a schematic diagram of the hardware structure of the semi-active suspension damping control device for the vehicle in this application. Detailed Implementation

[0077] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0078] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0079] In a first aspect, embodiments of this application provide a method for controlling the damping of a vehicle's semi-active suspension.

[0080] In one embodiment, reference is made to Figure 1 , Figure 1 This is a flowchart illustrating the semi-active suspension damping control method for the vehicle described in this application. Figure 1 As shown, the semi-active suspension damping control method for vehicles includes:

[0081] S1: Based on the vehicle's motion posture and the influence of each motion posture on the vehicle's ride comfort, establish a multi-degree-of-freedom vehicle dynamics model;

[0082] Furthermore, in one embodiment, based on the vehicle's motion posture and considering the impact of each motion posture on vehicle ride comfort, a multi-degree-of-freedom vehicle dynamics model is established, specifically as follows:

[0083] S101: The vehicle body is set as a rigid body with concentrated mass, and only the effects of vertical, roll and pitch motion on vehicle ride comfort are considered.

[0084] S102: Assume the vehicle is symmetrical about the longitudinal centerline and moves in uniform linear motion. Assume the road surface is a stable, normally random process with all states ergodic. Establish a seven-degree-of-freedom vehicle dynamics model.

[0085] Typically, there are three approaches to studying suspension systems: a seven-DOF vehicle model, a four-DOF suspension model, and a two-DOF suspension model. When the suspension mass distribution coefficient is close to 1, the vertical vibrations of the front and rear suspension systems are almost independent, thus simplifying the suspension system model to a two-DOF vibration system. This system, in addition to reflecting the dynamic characteristics of the vehicle body, also reflects the dynamic characteristics of the wheels when they resonate at high frequencies in the 10–15 Hz range. It has a significant impact on ride comfort and wheel contact with the ground, and more closely approximates the actual situation of a car suspension system.

[0086] To take vehicle roll into account, this application establishes a seven-degree-of-freedom vehicle dynamics model, such as... Figure 2 As shown, the three motions of the vehicle body—vertical, tilt, and pitch—are taken into account.

[0087] The seven-degree-of-freedom vehicle dynamics model in this application is based on the following premises: the vehicle body is considered as a rigid body with concentrated mass; only the vertical, roll, and pitch vibrations of the vehicle body are considered to affect the ride comfort, while the torsion of the vehicle body is ignored; the vehicle is symmetrical about the longitudinal centerline and moves in uniform linear motion; the road surface is a stable, ergodic, normally random process with isotropy; and other vibration sources other than the road surface are ignored.

[0088] for Figure 2 The meanings of the labels in this document are explained using the left front wheel as an example. The meanings and types of the labels on other wheels are as follows: m1 represents the mass of the left front wheel; C1 represents the equivalent damping coefficient of the left front tire; C2 represents the equivalent damping coefficient of the left front passive suspension; k1 represents the stiffness of the left front tire; k2 represents the stiffness of the left front suspension; F1 represents the adjustable damping output damping force of the left front shock absorber; z1 represents the vertical displacement of the left front wheel; z... 01 This represents the vertical displacement excitation of the road surface on the left front wheel. Others, I x I represents the moment of inertia of the vehicle body about its longitudinal axis around its center of mass. y I represents the moment of inertia of the vehicle body about its lateral axis of mass. z This represents the moment of inertia of the vehicle body about its vertical axis around its center of mass.

[0089] S2: Based on the established vehicle dynamics model with degrees of freedom, the vehicle vibration equation is calculated, and the variable damping output value is calculated based on the semi-active suspension damping force output control logic.

[0090] Specifically, the vehicle vibration equation is as follows:

[0091]

[0092] Where M represents the vehicle's mass matrix, C represents the vehicle's damping matrix, K represents the vehicle's stiffness matrix, and Z represents the displacement vectors of each degree of freedom of the vehicle. The first derivative of the displacement vector for each degree of freedom of the vehicle. K represents the second derivative of the displacement vector of each degree of freedom of the vehicle. t Let C represent the tire stiffness matrix, Q represent the road surface input vector (i.e., the road surface roughness), and C represent the road surface roughness matrix. t Let F represent the tire damping matrix and F represent the vehicle stiffness matrix.

[0093] The vehicle's stiffness matrix is ​​as follows:

[0094]

[0095] Where a represents the distance from the front axle to the vehicle's center of gravity, b represents the distance from the rear axle to the vehicle's center of gravity, c represents the distance from the right tire's contact point to the vehicle's center of gravity, d represents the distance from the left tire's contact point to the vehicle's center of gravity, k1 represents the stiffness of the left front tire, k2 represents the stiffness of the left front suspension, k3 represents the stiffness of the right front tire, k4 represents the stiffness of the right front suspension, k5 represents the stiffness of the left rear tire, k6 represents the stiffness of the left rear suspension, k7 represents the stiffness of the right rear tire, k8 represents the stiffness of the right rear suspension, and L represents the track width between the left and right wheels.

[0096] Specifically, the vehicle's damping matrix is ​​as follows:

[0097]

[0098] Wherein, C1 represents the equivalent damping coefficient of the left front tire, C2 represents the equivalent damping coefficient of the left front passive suspension, C3 represents the equivalent damping coefficient of the right front tire, C4 represents the equivalent damping coefficient of the right front passive suspension, C5 represents the equivalent damping coefficient of the left rear tire, C6 represents the equivalent damping coefficient of the left rear passive suspension, C7 represents the equivalent damping coefficient of the right rear tire, and C8 represents the equivalent damping coefficient of the right rear passive suspension.

[0099] Furthermore, the variable damping output value is calculated based on the semi-active suspension damping force output control logic, specifically as follows:

[0100] S201: Based on the vehicle vibration equation, determine the semi-active suspension damping force output control logic to obtain the adjustable damping output damping force of each shock absorber and the relative motion speed of each shock absorber.

[0101] The specific calculation method for the adjustable damping output damping force of each shock absorber is as follows:

[0102]

[0103]

[0104]

[0105]

[0106] Where F1 represents the adjustable damping output force of the left front shock absorber, F2 represents the adjustable damping output force of the right front shock absorber, F3 represents the adjustable damping output force of the left rear shock absorber, F4 represents the adjustable damping output force of the right rear shock absorber, and c1 max c2 indicates the maximum adjustable damping of the left front suspension. max This indicates the maximum adjustable damping of the right front suspension, c3. max This indicates the maximum adjustable damping of the left rear suspension, c4 max c1 represents the maximum adjustable damping of the right rear suspension. mex c2 represents the actual output damping of the variable damping system on the left front suspension. mex This indicates the actual output damping of the right front suspension variable damping, c3. mex c4 indicates the actual output damping of the left rear suspension variable damping. mex This indicates the actual output damping of the right rear suspension variable damping. This indicates the relative speed of the left front shock absorber. This indicates the relative speed of the right front shock absorber. This indicates the relative velocity of the left rear shock absorber. This indicates the relative velocity of the right rear shock absorber. This represents the first derivative of the vertical displacement at the connection point between the suspension and the front left side of the vehicle body. This represents the first derivative of the vertical displacement at the connection point between the suspension and the front right side of the vehicle body. This represents the first derivative of the vertical displacement at the connection point between the suspension and the left rear of the vehicle body. This represents the first derivative of the vertical displacement at the connection point between the suspension and the right rear of the vehicle body. This represents the first derivative of the vertical displacement of the left front wheel. This represents the first derivative of the vertical displacement of the right front wheel. This represents the first derivative of the vertical displacement of the left rear wheel. This represents the first derivative of the vertical displacement of the right rear wheel.

[0107] The specific calculation method for the relative motion velocity of each shock absorber is as follows:

[0108] z bw1 =z1-z 5lf

[0109] z bw2 =z2-z 5rf

[0110] z bw3 =z3-z 5lr

[0111] z bw4 =z4-z 5lr

[0112] Among them, z bw1 The z represents the relative displacement of the left front shock absorber. bw2 The z-axis represents the relative displacement of the right front shock absorber. bw3 The z-axis represents the relative displacement of the left rear shock absorber. bw4 The values ​​represent the relative displacement of the right rear shock absorber, z1 represents the vertical displacement of the left front wheel, z2 represents the vertical displacement of the right front wheel, z3 represents the vertical displacement of the left rear wheel, and z4 represents the vertical displacement of the right rear wheel. 5lf This indicates the vertical displacement at the connection point between the suspension and the front left side of the vehicle body, z. 5rf This indicates the vertical displacement at the connection point between the suspension and the front right side of the vehicle body, z. 5lr This indicates the vertical displacement at the connection point between the suspension and the left rear of the vehicle body, z. 5lr This indicates the vertical displacement at the connection point between the suspension and the right rear of the vehicle body;

[0113] Specifically, the calculation method for the vertical displacement at the connection point between the suspension and the vehicle body is as follows:

[0114] z 5lf =z5+a·z7-d·z6

[0115] z 5rf = z5 + a·z7 + c·z6

[0116] z 5lr =z5-b·z7-d·z6

[0117] z 5rr =z5-b·z7+c·z6

[0118] Where z5 represents the vertical displacement of the vehicle's center of gravity, z6 represents the roll angle displacement of the vehicle, z7 represents the pitch angle displacement of the vehicle, a represents the distance from the front axle to the vehicle's center of gravity, b represents the distance from the rear axle to the vehicle's center of gravity, c represents the distance from the right tire contact point to the vehicle's center of gravity, and d represents the distance from the left tire contact point to the vehicle's center of gravity.

[0119] S202: Based on the relative motion velocities of each shock absorber, determine the variable damping output value by optimizing the target method.

[0120] Furthermore, in one embodiment, based on the obtained relative motion velocities of each damper, the variable damping output value is determined by optimizing the target method, specifically as follows:

[0121] S2021: When any of the relative motion speeds of the left front shock absorber, right front shock absorber, left rear shock absorber, and right rear shock absorber are less than 0, the optimization target mode is executed to determine the variable damping output value.

[0122] S2022: Based on the changes in vehicle pitch and roll, as well as the relative movement of the vehicle's suspension connection points, continuous stepless adjustment of damping output is achieved;

[0123] The optimization objective method is specifically as follows:

[0124]

[0125] Where J represents the variable damping output value, and sqr represents the square root. The second derivative of the vertical displacement of the vehicle's center of mass is given. The second derivative of the roll angle displacement of the vehicle body is given. The second derivative of the pitch angle displacement of the vehicle body is given.

[0126] The variable damping adjustment strategy of this application is as follows: when any of the relative motion speeds of the left front shock absorber, the right front shock absorber, the left rear shock absorber, and the right rear shock absorber are less than 0, the optimization target method is executed to determine the variable damping output value to ensure the stability of the vehicle body posture. At the same time, based on the changes in vehicle pitch and roll, as well as the relative motion of the vehicle suspension connection points, the damping output is continuously and steplessly adjusted to achieve the purpose of real-time control across the entire frequency band.

[0127] S3: Adjusts PID parameters based on a preset intelligent algorithm, and achieves variable damping output control through the PID controller after parameter adjustment.

[0128] In this application, damping output control is specifically achieved through a PID controller. Due to its simple principle and mature technology, the PID controller is relatively easy to tune in practical applications and is widely used in industrial control. Its greatest advantage is that it does not require knowledge of the precise mathematical model of the controlled object; satisfactory results can be obtained simply by online tuning of the controller parameters based on simple parameters such as system error and the rate of change of error, demonstrating great adaptability and flexibility.

[0129] The integral action in PID control can reduce steady-state error, but it can also easily lead to integral saturation, increasing the system's overshoot. The derivative action can improve the system's response speed, but it is particularly sensitive to high-frequency disturbances and can even cause system instability. Therefore, correctly calculating the parameters of the PID controller and effectively and rationally designing it are of significant theoretical and practical importance for the widespread application of PID controllers in process control.

[0130] In practical applications, designing a PID controller involves determining its proportional, integral, and derivative coefficients. Different values ​​of these coefficients determine the strength of the proportional, integral, and derivative actions. Control system tuning, given a fixed control system structure and with the control instruments and controlled object in normal operating conditions, involves appropriately selecting the controller parameters to match the characteristics of the control instruments and the controlled object, thereby achieving optimal control performance.

[0131] In this application, the PID parameters are adjusted by a preset intelligent algorithm to obtain a PID controller with adjusted parameters. Then, based on the calculation process of the optimized target method of the PID controller with adjusted parameters, the variable damping output value is obtained, and the output control of damping is realized.

[0132] Specifically, in this application, the PID parameters are adjusted based on a preset intelligent algorithm, as follows:

[0133] S301: Perform parameter initialization and randomly generate an initial population. Specifically:

[0134] X = {x1, x2, ..., x} n} T

[0135] Where X represents the initial population, x n Let T represent a sparrow, and let T represent the matrix transpose.

[0136] S302: Execute the search algorithm:

[0137]

[0138] in, Let α represent the j-th dimension position information of the i-th sparrow in the t-th iteration, exp represent the exponential function with base e, and α represent the position of the i-th sparrow in the t-th iteration. t T represents a random number, with a value range of [0,1], that is, the random number obtained in the t-th iteration. max R2 represents the maximum number of iterations, R2 represents the warning value, which is a random number between [0,1], ST represents the safety threshold, which is a constant between [0.5,1], q represents a random number that follows a normal distribution, L represents a 1×d dimensional matrix of all 1s, and d represents a positive integer;

[0139] For α t The value of is calculated as follows:

[0140]

[0141] Where, α t-1 Let λ represent the random number taken in the (t-1)th iteration, where λ represents a random number with a value range of [0,1], and it needs to be randomly generated in each iteration;

[0142] S303: Update joiner positions:

[0143]

[0144] in, Let represent the worst individual in the t-th iteration, and n represent the total number of sparrows. This indicates the position of the optimal discoverer in the (t+1)th iteration;

[0145] S304: Updated awareness of danger:

[0146]

[0147] in, Let f represent the optimal individual in the t-th iteration, β represent a random number that follows a normal distribution with a mean of 0 and a variance of 1, and f i f represents the current fitness value of an individual. g This represents the current maximum fitness value, k represents a random number with a value of [-1, 1], the sign indicates the direction of the sparrow's movement, the size represents the step size control parameter, ε represents a constant, and f w This represents the current minimum fitness value;

[0148] S305: Based on the calculation method of updating awareness of danger, determine whether the stopping condition is met. If yes, output the optimal sparrow position. If not, execute the search algorithm again, update the position of the joiner and update the awareness of danger, and repeat this cycle until the stopping condition is met.

[0149] The vehicle semi-active suspension damping control method of this application establishes a multi-degree-of-freedom vehicle dynamics model based on the vehicle's motion posture and the influence of each motion posture on the vehicle's ride comfort. Then, based on the established multi-degree-of-freedom vehicle dynamics model, the vehicle vibration equation is calculated, and the variable damping output value is calculated according to the semi-active suspension damping force output control logic. Then, the PID parameters are adjusted based on a preset intelligent algorithm, and the variable damping output control is realized through the PID controller with adjusted parameters. This effectively solves the full-frequency adaptive correction of the semi-active suspension control strategy, ensuring the stability of the vehicle body posture. Furthermore, by establishing a seven-degree-of-freedom vehicle dynamics model that includes the semi-active suspension output damping force control strategy, and by adopting an improved control algorithm and integrating intelligent algorithms for PID parameter adjustment, human interference is avoided, resulting in a significant improvement in algorithm efficiency and robustness.

[0150] Secondly, embodiments of this application also provide a vehicle semi-active suspension damping control device.

[0151] In one embodiment, reference is made to Figure 3 , Figure 3 This is a schematic diagram of the functional modules of the semi-active suspension damping control device for the vehicle in this application. Figure 3 As shown, the vehicle semi-active suspension damping control device includes a creation module, a calculation module, and a control module.

[0152] The creation module is used to establish a multi-degree-of-freedom vehicle dynamics model based on the vehicle's motion posture and the influence of each motion posture on the vehicle's ride comfort; the calculation module is used to calculate the vehicle vibration equation based on the established multi-degree-of-freedom vehicle dynamics model, and to calculate the variable damping output value based on the semi-active suspension damping force output control logic; the control module is used to adjust the PID parameters based on a preset intelligent algorithm, and to realize variable damping output control through the PID controller after parameter adjustment.

[0153] The functions of each module in the above-mentioned vehicle semi-active suspension damping control device correspond to the steps in the above-mentioned vehicle semi-active suspension damping control method embodiment, and their functions and implementation processes will not be described in detail here.

[0154] Thirdly, embodiments of this application provide a vehicle semi-active suspension damping control device, which can be a personal computer (PC), laptop computer, server, or other device with data processing capabilities.

[0155] Reference Figure 4 , Figure 4This is a schematic diagram of the hardware structure of the semi-active suspension damping control device for vehicles involved in the embodiments of this application. In the embodiments of this application, the semi-active suspension damping control device for vehicles may include a processor, a memory, a communication interface, and a communication bus.

[0156] The communication bus can be of any type and is used to interconnect the processor, memory, and communication interface.

[0157] The communication interface includes input / output (I / O) interfaces, physical interfaces, and logical interfaces used for interconnecting components within the vehicle's semi-active suspension damping control equipment, as well as interfaces used for interconnecting the vehicle's semi-active suspension damping control equipment with other devices (such as other computing devices or user equipment). Physical interfaces can be Ethernet interfaces, fiber optic interfaces, ATM interfaces, etc.; user equipment can be displays, keyboards, etc.

[0158] Memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0159] The processor can be a general-purpose processor, which can call the vehicle semi-active suspension damping control program stored in the memory and execute the vehicle semi-active suspension damping control method provided in the embodiments of this application. For example, the general-purpose processor can be a central processing unit (CPU). The method executed when the vehicle semi-active suspension damping control program is called can be referred to in the various embodiments of the vehicle semi-active suspension damping control method of this application, and will not be repeated here.

[0160] Those skilled in the art will understand that Figure 4 The hardware structure shown does not constitute a limitation of this application and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0161] Fourthly, embodiments of this application also provide a computer-readable storage medium.

[0162] The present application has a computer-readable storage medium storing a vehicle semi-active suspension damping control program, wherein when the vehicle semi-active suspension damping control program is executed by a processor, it implements the steps of the vehicle semi-active suspension damping control method as described above.

[0163] The method implemented when the vehicle semi-active suspension damping control program is executed can be referred to in various embodiments of the vehicle semi-active suspension damping control method of this application, and will not be repeated here.

[0164] It should be noted that the sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0165] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. The terms "first," "second," and "third," etc., are used to distinguish different objects, etc., and do not indicate a sequence, nor do they limit "first," "second," and "third" to different types.

[0166] In the description of the embodiments of this application, terms such as "exemplary," "for example," or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplary," "for example," or "for instance" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary," "for example," or "for instance" is intended to present the relevant concepts in a concrete manner.

[0167] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more.

[0168] In some processes described in the embodiments of this application, multiple operations or steps are included in a specific order. However, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of this application, or they may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.

[0169] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of this application.

[0170] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method for controlling the damping of a vehicle's semi-active suspension, characterized in that, The semi-active vehicle suspension damping control method includes: Based on the vehicle's motion posture and the influence of each motion posture on the vehicle's ride comfort, a multi-degree-of-freedom vehicle dynamics model is established. Based on the established vehicle dynamics model with degrees of freedom, the vehicle vibration equation is calculated, and the variable damping output value is calculated based on the semi-active suspension damping force output control logic. The PID parameters are adjusted based on a preset intelligent algorithm, and the variable damping output control is achieved through the PID controller after parameter adjustment. Specifically, the variable damping output value calculated based on the semi-active suspension damping force output control logic is as follows: Based on the vehicle vibration equation, the semi-active suspension damping force output control logic is determined to obtain the adjustable damping output damping force of each shock absorber and the relative motion speed of each shock absorber. Based on the relative motion velocities of each shock absorber, the variable damping output value is determined by optimizing the target method. Specifically, determining the variable damping output value based on the obtained relative motion velocities of each shock absorber through an optimization target method involves: When any of the relative motion speeds of the left front shock absorber, right front shock absorber, left rear shock absorber, and right rear shock absorber are less than 0, the optimization target mode is executed to determine the variable damping output value. Based on the changes in vehicle pitch and roll, as well as the relative movement of the vehicle's suspension connection points, the damping output can be continuously and steplessly adjusted. The optimization objective method is specifically as follows: in, Indicates the variable damping output value. To represent square, The second derivative of the vertical displacement of the vehicle's center of mass is given. The second derivative of the roll angle displacement of the vehicle body is given. The second derivative of the pitch angle displacement of the vehicle body is given.

2. The semi-active suspension damping control method for a vehicle as described in claim 1, characterized in that, The multi-degree-of-freedom vehicle dynamics model is established based on the vehicle's motion posture and the impact of each motion posture on vehicle ride comfort. Specifically: The vehicle body is set as a rigid body with concentrated mass, and only the effects of vertical, roll and pitch motions on vehicle ride comfort are considered. Assume the vehicle is symmetrical about the longitudinal centerline and moves at a constant speed in a straight line. Assume the road surface is a stable, normally distributed random process with all states ergodic, and establish a seven-degree-of-freedom vehicle dynamics model.

3. The semi-active suspension damping control method for a vehicle as described in claim 2, characterized in that, The specific vehicle vibration equation is as follows: in, Represents the mass matrix of the vehicle. This represents the vehicle's damping matrix. This represents the stiffness matrix of the vehicle. This represents the displacement vector for each degree of freedom of the vehicle. The first derivative of the displacement vector for each degree of freedom of the vehicle. The second derivative of the displacement vector for each degree of freedom of the vehicle. Represents the tire stiffness matrix. This represents the road surface input vector, i.e., the road surface roughness. This represents the tire damping matrix. Represents the vehicle's stiffness matrix; The vehicle's stiffness matrix is ​​as follows: in, Indicates the distance from the front axle to the vehicle's center of gravity. Indicates the distance from the rear axle to the vehicle's center of gravity. This indicates the distance from the contact point of the right tire to the vehicle's center of gravity. This indicates the distance from the contact point of the left tire to the vehicle's center of gravity. Indicates the stiffness of the left front tire. This indicates the stiffness of the left front suspension. This indicates the stiffness of the right front tire. This indicates the stiffness of the right front suspension. Indicates the stiffness of the left rear tire. Indicates the stiffness of the left rear suspension. Indicates the stiffness of the right rear tire. Indicates the stiffness of the right rear suspension. Indicates the wheelbase between the left and right wheels; Specifically, the vehicle's damping matrix is ​​as follows: in, This indicates the equivalent damping coefficient of the left front tire. This indicates the equivalent damping coefficient of the left front passive suspension. This indicates the equivalent damping coefficient of the right front tire. This indicates the equivalent damping coefficient of the right front passive suspension. This indicates the equivalent damping coefficient of the left rear tire. This indicates the equivalent damping coefficient of the left rear passive suspension. This indicates the equivalent damping coefficient of the right rear tire. This indicates the equivalent damping coefficient of the right rear passive suspension.

4. The semi-active suspension damping control method for a vehicle as described in claim 3, characterized in that: The semi-active suspension damping force output control logic is determined to obtain the adjustable damping output damping force of each shock absorber and the relative motion velocity of each shock absorber. Specifically, the calculation method for the adjustable damping output damping force of each shock absorber is as follows: in, This indicates the adjustable damping output damping force of the left front shock absorber. This indicates the adjustable damping output damping force of the right front shock absorber. This indicates the adjustable damping output damping force of the left rear shock absorber. This indicates the adjustable damping output damping force of the right rear shock absorber. This indicates the maximum damping of the left front suspension variable energy adjustable. This indicates the maximum damping of the right front suspension variable energy adjustable system. This indicates the maximum damping of the left rear suspension variable energy adjustment mechanism. This indicates the maximum damping of the right rear suspension, which is adjustable via variable energy. This indicates the actual output damping of the left front suspension variable damping. This indicates the actual output damping of the right front suspension variable damping. This indicates the actual output damping of the left rear suspension variable damping. This indicates the actual output damping of the right rear suspension variable damping. This indicates the relative speed of the left front shock absorber. This indicates the relative speed of the right front shock absorber. This indicates the relative velocity of the left rear shock absorber. This indicates the relative velocity of the right rear shock absorber. This represents the first derivative of the vertical displacement at the connection point between the suspension and the front left side of the vehicle body. This represents the first derivative of the vertical displacement at the connection point between the suspension and the front right side of the vehicle body. This represents the first derivative of the vertical displacement at the connection point between the suspension and the left rear of the vehicle body. This represents the first derivative of the vertical displacement at the connection point between the suspension and the right rear of the vehicle body. This represents the first derivative of the vertical displacement of the left front wheel. This represents the first derivative of the vertical displacement of the right front wheel. This represents the first derivative of the vertical displacement of the left rear wheel. This represents the first derivative of the vertical displacement of the right rear wheel. The semi-active suspension damping force output control logic is determined to obtain the adjustable damping output damping force of each shock absorber and the relative motion speed of each shock absorber. The specific calculation method for the relative motion speed of each shock absorber is as follows: in, This indicates the relative displacement of the left front shock absorber. This indicates the relative displacement of the right front shock absorber. This indicates the relative displacement of the left rear shock absorber. This indicates the relative displacement of the right rear shock absorber. This indicates the vertical displacement of the left front wheel. This indicates the vertical displacement of the right front wheel. This indicates the vertical displacement of the left rear wheel. This indicates the vertical displacement of the right rear wheel. This indicates the vertical displacement at the connection point between the suspension and the front left side of the vehicle body. This indicates the vertical displacement at the connection point between the suspension and the front right side of the vehicle body. This indicates the vertical displacement at the connection point between the suspension and the left rear of the vehicle body. This indicates the vertical displacement at the connection point between the suspension and the right rear of the vehicle body; Specifically, the calculation method for the vertical displacement at the connection point between the suspension and the vehicle body is as follows: in, This represents the vertical displacement of the vehicle's center of gravity. This indicates the roll angle displacement of the vehicle body. This indicates the pitch angle displacement of the vehicle body. Indicates the distance from the front axle to the vehicle's center of gravity. Indicates the distance from the rear axle to the vehicle's center of gravity. This indicates the distance from the contact point of the right tire to the vehicle's center of gravity. This indicates the distance from the contact point of the left tire to the vehicle's center of gravity.

5. The semi-active suspension damping control method for a vehicle as described in claim 1, characterized in that, The adjustment of PID parameters based on a preset intelligent algorithm specifically includes: Perform parameter initialization and randomly generate an initial population. Specifically: in, Indicates the initial population. It represents sparrow. Indicates matrix transpose; Execute the search algorithm: in, Indicates the first Only sparrows in the first The th iteration Dimensional location information, This represents an exponential function with base e. Represents a random number, with a value range of 1000. , Indicates the maximum number of iterations. This represents the warning value, which has a value of [value]. Random numbers between, This represents the safety threshold, with a value of [value missing]. The constants between, Represents a random number that follows a normal distribution. Let represent a 1×d dimensional matrix consisting entirely of 1s, where d represents a positive integer; Update joiner positions: in, Indicates the first The worst individual in the next iteration, This represents the total number of sparrows. Indicates the first The position of the optimal discoverer in the next iteration; Update: Aware of the danger: in, Indicates the first The best individual in the next iteration. This represents a random number that follows a normal distribution with a mean of 0 and a variance of 1. This represents the current fitness value of an individual. This represents the current maximum fitness value. Indicates the value to be The random number is represented by a sign indicating the sparrow's movement direction, and its magnitude represents the step size control parameter. Represents a constant. This represents the current minimum fitness value; Based on the calculation method of updating the awareness of danger, it is determined whether the stopping condition is met. If so, the optimal sparrow position is output. If not, the search algorithm is executed again, and the position of the joiner and the awareness of danger are updated. This process is repeated until the stopping condition is met.

6. A semi-active suspension damping control device for vehicles, characterized in that, The vehicle semi-active suspension damping control device includes: Create a module that is used to establish a multi-degree-of-freedom vehicle dynamics model based on the vehicle's motion posture and the influence of each motion posture on the vehicle's ride comfort. The calculation module is used to calculate the vehicle vibration equation based on the established vehicle dynamics model with degrees of freedom, and to calculate the variable damping output value based on the semi-active suspension damping force output control logic. The control module is used to adjust the PID parameters based on a preset intelligent algorithm, and to achieve variable damping output control through the PID controller after parameter adjustment. Specifically, the variable damping output value calculated based on the semi-active suspension damping force output control logic is as follows: Based on the vehicle vibration equation, the semi-active suspension damping force output control logic is determined to obtain the adjustable damping output damping force of each shock absorber and the relative motion speed of each shock absorber. Based on the relative motion velocities of each shock absorber, the variable damping output value is determined by optimizing the target method. Specifically, determining the variable damping output value based on the obtained relative motion velocities of each shock absorber through an optimization target method involves: When any of the relative motion speeds of the left front shock absorber, right front shock absorber, left rear shock absorber, and right rear shock absorber are less than 0, the optimization target mode is executed to determine the variable damping output value. Based on the changes in vehicle pitch and roll, as well as the relative movement of the vehicle's suspension connection points, the damping output can be continuously and steplessly adjusted. The optimization objective method is specifically as follows: in, Indicates the variable damping output value. To represent square, The second derivative of the vertical displacement of the vehicle's center of mass is given. The second derivative of the roll angle displacement of the vehicle body is given. The second derivative of the pitch angle displacement of the vehicle body is given.

7. A semi-active suspension damping control device for vehicles, characterized in that, The vehicle semi-active suspension damping control device includes a processor, a memory, and a vehicle semi-active suspension damping control program stored in the memory and executable by the processor, wherein when the vehicle semi-active suspension damping control program is executed by the processor, it implements the steps of the vehicle semi-active suspension damping control method as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a vehicle semi-active suspension damping control program, wherein when the vehicle semi-active suspension damping control program is executed by a processor, it implements the steps of the vehicle semi-active suspension damping control method as described in any one of claims 1 to 5.

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