Magneto-rheological seat control method and system and vehicle

Abstract

The invention relates to the technical field of seat damping, in particular to a magneto-rheological seat control method and system and a vehicle, and the method comprises the steps that a target signal set is obtained, and the target signal set comprises acceleration signals of a magneto-rheological seat; according to the target signal set and a preset target mapping relation, target damping force is obtained, and the target mapping relation refers to the mapping relation between the signal set and the damping force; determining a difference value between the target damping force and an actual damping force of the magnetorheological seat as a target difference value, and determining a target control current according to the target difference value; and based on the target control current, controlling the magneto-rheological seat, according to the method, self-adaptive adjustment of the damping force of the magneto-rheological seat is well achieved, that is, different target control currents can be obtained based on different acceleration signals of the magneto-rheological seat, so that control over the damping force of the magneto-rheological seat is achieved, and the comfort and stability of the magneto-rheological seat are effectively improved.

Description

Technical Field

[0001] The present application relates to the technical field of seat shock absorption, and in particular to a magnetorheological seat control method, system and vehicle. Background Art

[0002] Magnetorheological (MR) seats are a new type of seat system developed based on magnetorheological materials. They are widely used in automobiles, aviation, and other fields where people need to maintain a sitting posture for a long time. Magnetorheological materials are a type of material with controllable rheological properties. By adjusting the external magnetic field, their viscosity and fluidity can be changed, thereby changing the size of their damping force.

[0003] In the related art, the damping force adjustment of magnetorheological seats usually relies on a fixed control mode, such as manual adjustment, or simply setting the corresponding damping force according to the driving mode, etc. However, this method is difficult to adapt to complex external environments. For example, when facing complex road conditions, this method cannot well perform adaptive adjustment of the damping force according to different road conditions, resulting in poor comfort and stability of the magnetorheological seat. Summary of the invention

[0004] The present application provides a magnetorheological seat control method, system and vehicle to solve the problem in the related art that the damping force adjustment method of the magnetorheological seat is difficult to adapt to the complex external environment, resulting in poor comfort and stability of the magnetorheological seat.

[0005] The present application provides a magnetorheological seat control method, the method comprising: acquiring a target signal set, the target signal set comprising an acceleration signal of the magnetorheological seat;

[0006] Obtaining a target damping force according to the target signal set and a preset target mapping relationship, wherein the target mapping relationship refers to a mapping relationship between the signal set and the damping force;

[0007] Determining a difference between the target damping force and an actual damping force of the magnetorheological seat as a target difference, and determining a target control current according to the target difference;

[0008] The magnetorheological seat is controlled based on the target control current.

[0009] In one embodiment of the present application, the actual damping force is the damping force output by the magnetorheological damper in the magnetorheological seat, and the step of obtaining the actual damping force includes:

[0010] Acquiring a first feedback current of the magnetorheological damper;

[0011] The actual damping force is obtained according to the first feedback current and the preset actual mapping relationship, wherein the actual mapping relationship refers to the mapping relationship between the feedback current and the damping force, and the actual mapping relationship is obtained based on a preset data set, wherein the data set includes a plurality of sample points, and each of the sample points includes: a current value sample and a damping force sample of the magnetorheological damper, and the current value sample corresponds to the damping force sample.

[0012] In one embodiment of the present application, the sample point also includes a relative motion speed, and the relative motion speed refers to the motion speed of the piston of the magnetorheological damper relative to the cylinder of the magnetorheological damper. The current value sample, the damping force sample, and the relative motion speed in the sample point correspond to each other. The step of obtaining the actual mapping relationship includes:

[0013] Using the plurality of sample points, calibrating the coefficients to be calibrated in the preset damping function to be calibrated, and determining the calibrated damping function to be calibrated as the actual mapping relationship;

[0014] The dependent variable in the damping function to be calibrated is the damping force, and the independent variable expression in the damping function to be calibrated refers to the sum of the viscous damping term, the Coulomb friction force, and the current damping term, the viscous damping term refers to the product of the viscosity coefficient and the relative motion speed, the current damping term refers to the product of the damping coefficient and the current damping force, the current damping force is obtained by performing a hyperbolic tangent operation on the current proportional value, and the current proportional value refers to the product of the proportional coefficient and the current value, wherein the viscosity coefficient, the Coulomb friction force, the damping coefficient, and the proportional coefficient are all the coefficients to be calibrated.

[0015] In an embodiment of the present application, using the plurality of sample points to calibrate the coefficients to be calibrated in the preset damping function to be calibrated includes:

[0016] Substituting the current value samples and the relative motion speed in the sample points into the damping function to be calibrated to obtain a damping force measurement value;

[0017] determining a difference between the damping force measurement value and a corresponding damping force sample as a first error value;

[0018] The coefficients to be calibrated are iterated based on the multiple first error values ​​to complete the calibration of the coefficients to be calibrated.

[0019] In an embodiment of the present application, using the plurality of sample points to calibrate the coefficients to be calibrated in the preset damping function to be calibrated includes:

[0020] Substituting the damping force sample and the relative motion speed at the sample point into the damping function to be calibrated to obtain a current measurement value;

[0021] determining a difference between the current measurement value and the corresponding current value sample as a second error value;

[0022] The coefficient to be calibrated is iterated based on a plurality of the second error values ​​to complete calibration of the coefficient to be calibrated.

[0023] In an embodiment of the present application, iterating the coefficient to be calibrated based on the plurality of first error values ​​to complete the calibration of the coefficient to be calibrated includes:

[0024] Based on the plurality of the first error values, determining a first objective function, wherein a dependent variable expression of the first objective function is a sum of a plurality of target quantities, and the target quantity refers to a square value of the first error value;

[0025] Calculating partial derivatives of each of the coefficients to be calibrated in the first objective function to obtain partial derivatives of each of the coefficients to be calibrated;

[0026] Based on the partial derivatives, an update rule for each of the coefficients to be calibrated is obtained, wherein the update rule includes: determining the product of a preset learning rate and the partial derivative as an update term, and determining the difference between the original value of the coefficient to be calibrated and the corresponding update term as the update value of the current coefficient to be calibrated;

[0027] Based on the update rule, the coefficients to be calibrated are iterated until the value of the first objective function is less than a preset convergence threshold or a preset number of iterations is reached to obtain a final value of each coefficient to be calibrated; and the final value of the coefficient to be calibrated is calibrated to the damping function to be calibrated.

[0028] In one embodiment of the present application, the acceleration signal includes: a vertical acceleration signal and a lateral acceleration signal, and the target signal set also includes: a whole vehicle CAN signal and a vertical velocity signal of a magnetorheological seat, the whole vehicle CAN signal includes the body lateral acceleration, body vertical acceleration, and vehicle speed of the vehicle in which the magnetorheological seat is located, and the vertical velocity signal of the magnetorheological seat is obtained by integrating the vertical acceleration signal of the magnetorheological seat.

[0029] In one embodiment of the present application, the step of acquiring the target mapping relationship includes:

[0030] Acquire preset initial mapping information, the initial mapping information comprising: a signal set and an initial damping value, the signal set and the initial damping value are in one-to-one correspondence, wherein the initial damping value is positively correlated with the vertical velocity of the magnetorheological seat in the signal set;

[0031] According to the vehicle body lateral acceleration, vehicle body vertical acceleration, and vehicle speed in the signal set, the corresponding initial damping value is increased or decreased to obtain the target mapping relationship.

[0032] In one embodiment of the present application, the step of determining the target control current according to the target difference includes:

[0033] Determine a product of the target difference and a preset first proportional gain as a first intermediate value;

[0034] Integrating the target difference to obtain a second intermediate value, and determining a product of the second intermediate value and a preset first integral gain as a third intermediate value;

[0035] Performing a differential operation on the target difference to obtain a fourth intermediate value, and determining a product of the fourth intermediate value and a preset first differential gain as a fifth intermediate value;

[0036] A sum of the first intermediate value, the third intermediate value, and the fifth intermediate value is determined as the target control current.

[0037] In one embodiment of the present application, controlling the magnetorheological seat based on the target control current includes:

[0038] Acquiring a second feedback current of a magnetorheological damper in the magnetorheological seat, and determining a difference between the target control current and the second feedback current as a value to be processed;

[0039] Determine the product of the to-be-processed value and a preset second proportional gain as a sixth intermediate value;

[0040] Integrating the value to be processed to obtain a seventh intermediate value, and determining a product of the seventh intermediate value and a preset second integral gain as an eighth intermediate value;

[0041] Performing a differential operation on the value to be processed to obtain a ninth intermediate value, and determining a product of the ninth intermediate value and a preset second differential gain as a tenth intermediate value;

[0042] determining a sum of the sixth intermediate value, the eighth intermediate value, and the tenth intermediate value as the target duty cycle;

[0043] The magnetorheological damper is controlled based on the target duty cycle.

[0044] In one embodiment of the present application, it further includes:

[0045] Acquiring a height signal of the magnetorheological seat;

[0046] If the height of the magnetorheological seat exceeds a preset height threshold range, the magnetorheological damper in the magnetorheological seat is controlled based on a preset target current to increase the damping force output by the magnetorheological damper.

[0047] The present application also provides a magnetorheological seat control system, comprising:

[0048] A signal acquisition module, used to acquire a target signal set, wherein the target signal set includes an acceleration signal of a magnetorheological seat;

[0049] A target damping force acquisition module, used to obtain a target damping force according to the target signal set and a preset target mapping relationship, wherein the target mapping relationship refers to a mapping relationship between a signal set and a damping force;

[0050] a target control current acquisition module, configured to determine a difference between the target damping force and an actual damping force of the magnetorheological seat as a target difference, and determine a target control current according to the target difference;

[0051] A control module is used to control the magnetorheological seat based on the target control current.

[0052] The present application also provides a vehicle, comprising: a magnetorheological seat control system as described above.

[0053] Beneficial effects of the embodiments of the present application: The magnetorheological seat control method, system and vehicle provided by the embodiments of the present application, the method obtains a target signal set, the target signal set includes the acceleration signal of the magnetorheological seat; obtains the target damping force according to the target signal set and the preset target mapping relationship, the target mapping relationship refers to the mapping relationship between the signal set and the damping force; determines the difference between the target damping force and the actual damping force of the magnetorheological seat as the target difference, determines the target control current according to the target difference; controls the magnetorheological seat based on the target control current; the method better realizes the adaptive adjustment of the damping force of the magnetorheological seat, that is, based on different acceleration signals of the magnetorheological seat, different target control currents can be obtained to realize the control of the damping force of the magnetorheological seat. It can be understood that different acceleration signals of the magnetorheological seat correspond to different road conditions and working conditions (working conditions of the vehicle where the magnetorheological seat is located), for example: if the vertical acceleration signal of the magnetorheological seat is large, and the lateral acceleration is large, it indicates that the vehicle may be in a relatively bumpy section and is turning, etc. Therefore, through this method, adaptive adjustment of the damping force of the magnetorheological seat under different external environments can be achieved, effectively improving the comfort and stability of the magnetorheological seat. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 A schematic flow chart of a magnetorheological seat control method provided in one embodiment of the present application;

[0055] Figure 2 A schematic diagram of a flow chart of obtaining a target control current in a magnetorheological seat control method provided in an embodiment of the present application;

[0056] Figure 3 A schematic diagram of the structure of a magnetorheological seat control system provided in one embodiment of the present application;

[0057] Figure 4 A schematic diagram of a practical application of a magnetorheological seat control system provided by an embodiment of the present application;

[0058] Figure 5 A schematic diagram of the structure of an electronic device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0059] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0060] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application, and thus the drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed at will, and the component layout may also be more complicated.

[0061] In the following description, a large number of details are discussed to provide a more thorough explanation of the embodiments of the present application. However, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present application difficult to understand.

[0062] Combine the following Figures 1 to 5 , the magnetorheological seat control method, system and vehicle provided in this application are explained.

[0063] See also Figure 1 , Figure 1 A schematic diagram of a flow chart of a magnetorheological seat control method provided in an embodiment of the present application, such as Figure 1 As shown, the method includes:

[0064] S110: Acquire a target signal set, where the target signal set includes an acceleration signal of the magnetorheological seat.

[0065] It can be understood that by acquiring the acceleration signal of the magnetorheological seat, it is possible to easily determine the current road condition of the vehicle where the magnetorheological seat is located, as well as the current working condition of the vehicle, and then make corresponding damping force adjustments.

[0066] S120: Obtaining a target damping force according to the target signal set and a preset target mapping relationship, where the target mapping relationship refers to a mapping relationship between a signal set and a damping force.

[0067] It can be understood that different signal sets in the target mapping relationship correspond to different damping forces. By setting the target mapping relationship and obtaining the target damping force based on the target mapping relationship and the target signal set, the subsequent adaptive control of the damping force of the magnetorheological seat can be facilitated.

[0068] S130: Determine the difference between the target damping force and the actual damping force of the magnetorheological seat as a target difference, and determine a target control current according to the target difference.

[0069] It should be noted that a mapping relationship between the target difference and the control current may be preset, and the corresponding target control current may be obtained according to the target difference and the mapping relationship.

[0070] S140: Controlling the magnetorheological seat based on the target control current.

[0071] In some examples of embodiments, a corresponding current signal may be sent to a magnetorheological damper of the magnetorheological seat based on the target control current to control the damping force output by the magnetorheological damper.

[0072] In some embodiments, the actual damping force is the damping force output by the magnetorheological damper in the magnetorheological seat, and the step of obtaining the actual damping force includes:

[0073] 1. Obtaining a first feedback current of the magnetorheological damper.

[0074] 2. The actual damping force is obtained according to the first feedback current and a preset actual mapping relationship. The actual mapping relationship refers to a mapping relationship between the feedback current and the damping force. The actual mapping relationship is obtained based on a preset data set. The data set includes multiple sample points. Each of the sample points includes: a current value sample and a damping force sample of the magnetorheological damper. The current value sample and the damping force sample correspond to each other.

[0075] It is understandable that the above method can facilitate the acquisition of the actual damping force of the magnetorheological damper. Moreover, by acquiring the actual mapping relationship based on a preset data set, the accuracy is relatively high.

[0076] In some examples of embodiments, when the data set is obtained, deep learning or other methods can be used to complete the determination of the actual mapping relationship. For example: the current value samples in the data set are input into a preset neural network model to obtain the damping force prediction value output by the neural network model; based on the gap between the damping force prediction value and the corresponding damping force sample, the neural network model is trained until the model converges, and the neural network model finally obtained represents the actual mapping relationship.

[0077] In some embodiments, the sample point also includes a relative motion speed, and the relative motion speed refers to the motion speed of the piston of the magnetorheological damper relative to the cylinder of the magnetorheological damper. The current value sample, the damping force sample, and the relative motion speed in the sample point correspond to each other. The step of obtaining the actual mapping relationship includes:

[0078] The coefficients to be calibrated in the preset damping function to be calibrated are calibrated by using the plurality of sample points, and the calibrated damping function to be calibrated is determined as the actual mapping relationship.

[0079] The dependent variable in the damping function to be calibrated is the damping force, and the independent variable expression in the damping function to be calibrated refers to the sum of the viscous damping term, the Coulomb friction force, and the current damping term, the viscous damping term refers to the product of the viscosity coefficient and the relative motion speed, the current damping term refers to the product of the damping coefficient and the current damping force, the current damping force is obtained by performing a hyperbolic tangent operation on the current proportional value, and the current proportional value refers to the product of the proportional coefficient and the current value, wherein the viscosity coefficient, the Coulomb friction force, the damping coefficient, and the proportional coefficient are all the coefficients to be calibrated.

[0080] It should be noted that in the above embodiment, the damping function to be calibrated is determined by combining the viscous damping term, Coulomb friction, and current damping term, so that the rationality of the damping function to be calibrated is higher and it is convenient to improve the accuracy of the subsequent actual mapping relationship.

[0081] In some embodiments, the mathematical expression of the damping function to be calibrated is:

[0082] F d =c1V+F c +c2 tanh(kI)

[0083] Among them, F dis the dependent variable of the damping function to be calibrated, that is, the damping force output by the magnetorheological damper, c1v is the viscous damping term, c1 is the viscosity coefficient, which is related to the relative motion speed, v represents the relative motion speed, F c represents the Coulomb friction force, c2tanh(kI) is the current damping term, that is, the damping force generated by the magnetorheological nonlinear effect caused by the current (the current that controls the magnetorheological damper), c2 represents the damping coefficient, tanh(kI) represents the current damping force, tanh(·) represents the hyperbolic tangent function, kI is the current proportional value, k represents the proportional coefficient, and I represents the current value.

[0084] In some embodiments, calibrating the coefficients to be calibrated in the preset damping function to be calibrated using the plurality of sample points includes:

[0085] 1. Substitute the current value samples and relative motion speed at the sample points into the damping function to be calibrated to obtain the damping force measurement value.

[0086] 2. Determine the difference between the damping force measurement value and the corresponding damping force sample as the first error value.

[0087] For example, it is assumed that the mathematical expression of the sample point is (I j , F d，j , v j ), where I j represents the current value sample at the jth sample point, F d，j represents the damping force sample at the jth sample point, v j represents the relative motion speed of the jth sample point. Then, the mathematical expression of the first error value is:

[0088] e j1 =c1v j +F c +c2 tanh(kI j )-F d，j

[0089] Among them, e j1 Represents the first error value.

[0090] 3. Based on the multiple first error values, iterate the coefficients to be calibrated to complete the calibration of the coefficients to be calibrated.

[0091] It can be understood that an initial value is first assigned to each coefficient to be calibrated, and then the current value sample and the relative motion speed in the sample point are substituted into the damping function to be calibrated to obtain the damping force measurement value. Based on the difference between the damping force measurement value and the corresponding damping force sample, the coefficient to be calibrated is iterated until the difference between the damping force measurement value and the corresponding damping force sample is less than a preset convergence threshold, or the preset number of iterations is reached, so as to determine the final value of each coefficient to be calibrated, and calibrate the final value to the damping function to be calibrated. In the above manner, the calibration of the coefficient to be calibrated can be completed well with high accuracy.

[0092] In some examples of embodiments, the calibration coefficients may be iterated by a method such as a dichotomy method.

[0093] In some embodiments, calibrating the coefficients to be calibrated in the preset damping function to be calibrated using the plurality of sample points includes:

[0094] 1. Substitute the damping force sample and the relative motion speed at the sample point into the damping function to be calibrated to obtain the current measurement value.

[0095] It can be understood that by converting the mathematical expression of the damping function to be calibrated in the above embodiment, the following is obtained:

[0096]

[0097] Wherein, arctanh(·) represents the inverse hyperbolic tangent function. By substituting the damping force sample and the relative motion speed at the sample point into the damping function to be calibrated, the current measurement value can be obtained.

[0098] Then, substituting the damping force sample and relative motion speed at the sample point into the above mathematical expression, the current measurement value is obtained

[0099] 2. Determine the difference between the current measurement value and the corresponding current value sample as the second error value. The mathematical expression of the second error value is:

[0100]

[0101] Among them, e j2 Represents the second error value.

[0102] 3. Based on the plurality of second error values, iterate the coefficients to be calibrated to complete calibration of the coefficients to be calibrated.

[0103] It should be noted that by using the above method to complete the calibration, the accuracy is relatively high.

[0104] In some embodiments, iterating the coefficient to be calibrated based on the plurality of first error values ​​to complete calibration of the coefficient to be calibrated includes:

[0105] 1. Based on the multiple first error values, determine a first objective function, wherein the dependent variable expression of the first objective function is the sum of multiple target quantities, and the target quantity refers to the square value of the first error value.

[0106] The mathematical expression of the first objective function is:

[0107]

[0108] Among them, G(c1,F c ,c2,k)1 represents the first objective function.

[0109] 2. Calculate the partial derivative of each of the coefficients to be calibrated in the first objective function to obtain the partial derivative of each of the coefficients to be calibrated.

[0110] 3. Based on the partial derivatives, an update rule for each of the coefficients to be calibrated is obtained, and the update rule includes: determining the product of a preset learning rate and the partial derivative as an update term, and determining the difference between the original value of the coefficient to be calibrated and the corresponding update term as the update value of the current coefficient to be calibrated.

[0111] 4. Based on the update rule, the coefficients to be calibrated are iterated until the value of the first objective function is less than a preset convergence threshold or a preset number of iterations is reached to obtain a final value of each coefficient to be calibrated; and the final value of the coefficient to be calibrated is calibrated to the damping function to be calibrated.

[0112] It should be noted that, through the above method, the calibration of the calibration coefficient can be better achieved with high accuracy.

[0113] In some embodiments, iterating the coefficient to be calibrated based on the plurality of second error values ​​to complete calibration of the coefficient to be calibrated includes:

[0114] 1. Based on multiple second error values, determine a second objective function, where the dependent variable expression of the second objective function is the sum of multiple error amounts, and the error amount refers to the square value of the second error value.

[0115] The mathematical expression of the second objective function is:

[0116]

[0117] Among them, G(c1,F c ,c2,k)2 represents the second objective function.

[0118] 2. Calculate the partial derivative of each of the coefficients to be calibrated in the second objective function to obtain the partial derivative of each of the coefficients to be calibrated.

[0119] It should be noted that in order to facilitate the subsequent application of the gradient descent method, the partial derivative of each coefficient to be calibrated in the second objective function is calculated separately to obtain:

[0120]

[0121] Where G2 is G(c1,F c ,c2,k)2 abbreviation, It means to find the partial derivative of c1 in the second objective function.

[0122]

[0123] in, Indicates the F in the second objective function c Find the partial derivative.

[0124]

[0125] in, It means to find the partial derivative of c2 in the second objective function.

[0126]

[0127] in, It means to find the partial derivative of k in the second objective function.

[0128] 3. Based on the partial derivative, an update rule for each of the coefficients to be calibrated is obtained, and the update rule includes: determining the product of a preset learning rate and the partial derivative as an update term, and determining the difference between the original value of the coefficient to be calibrated and the corresponding update term as the update value of the current coefficient to be calibrated.

[0129] It should be noted that in the gradient descent method, the parameter update formula of the second objective function is:

[0130]

[0131] Among them, θ represents the coefficient set to be calibrated {c1, F c ,c2,k},θ i+1 represents the updated value of the coefficient to be calibrated, that is, the updated value of the parameter to be calibrated, θ i represents the current value of the coefficient to be calibrated, α represents the preset learning rate, It means that partial derivatives of the coefficients to be calibrated in the second objective function are obtained respectively.

[0132] 4. Based on the update rule, the coefficients to be calibrated are iterated until the value of the first objective function is less than a preset convergence threshold or a preset number of iterations is reached to obtain a final value of each coefficient to be calibrated; and the final value of the coefficient to be calibrated is calibrated to the damping function to be calibrated.

[0133] It can be understood that the mathematical expression for updating c1 is:

[0134]

[0135] in, represents the updated value of c1, Indicates the current value of c1 (the value before updating).

[0136] F c The mathematical expression for the update is:

[0137]

[0138] in, Indicates F c The updated value of Indicates F c The current value of (updates the previous value).

[0139] The mathematical expression for updating c2 is:

[0140]

[0141] in, represents the updated value of c2, Indicates the current value of c2 (the value before updating).

[0142] The mathematical expression for updating k is:

[0143]

[0144] Among them, k new represents the updated value of k, k old Indicates the current value of k (updates the previous value).

[0145] It can be understood that, through the above method, relatively accurate values ​​of each coefficient to be calibrated can be obtained.

[0146] In some embodiments, the acceleration signal includes: a vertical acceleration signal and a lateral acceleration signal, and the target signal set also includes: a whole vehicle CAN signal and a vertical velocity signal of a magnetorheological seat, the whole vehicle CAN signal includes the body lateral acceleration, body vertical acceleration, and vehicle speed of the vehicle in which the magnetorheological seat is located, and the vertical velocity signal of the magnetorheological seat is obtained by integrating the vertical acceleration signal of the magnetorheological seat.

[0147] In some embodiments, in order to avoid the vertical velocity signal from having a zero drift, the vertical velocity signal may be subjected to a high-pass filter to eliminate the interference of low-frequency signals.

[0148] It should be noted that by collecting the above-mentioned vehicle CAN (Controller Area Network) signal and the vertical speed signal of the magnetorheological seat, it is possible to accurately identify the road conditions and vehicle operating conditions in the subsequent control process.

[0149] In some embodiments, the step of acquiring the target mapping relationship includes:

[0150] 1. Obtaining preset initial mapping information, the initial mapping information includes: a signal set and an initial damping value, the signal set and the initial damping value are in one-to-one correspondence, wherein the initial damping value is positively correlated with the vertical velocity of the magnetorheological seat in the signal set.

[0151] It can be understood that each signal set includes a group of signals, namely, the lateral acceleration of the vehicle body, the vertical acceleration of the vehicle body, the vehicle speed, the vertical acceleration signal of the magnetorheological seat, and the lateral acceleration signal, etc. Each signal set corresponds to an initial damping value, so that the corresponding initial damping value can be adjusted based on the lateral acceleration of the vehicle body, the vertical acceleration of the vehicle body, and the vehicle speed, etc. in the signal set. The initial damping value can be set according to actual conditions.

[0152] In some embodiments, the initial damping value can be set according to two situations. One is that when the vertical speed of the magnetorheological seat is less than the preset first speed threshold (usually negative), it means that the magnetorheological seat is currently subjected to a large downward impact. At this time, a larger anti-compression damping force can be set according to actual needs, and the anti-compression damping force is set as the initial damping value in this case. The second is that when the vertical speed of the magnetorheological seat is greater than the preset second speed threshold (usually positive), it means that the magnetorheological seat is currently subjected to a large upward impact, or the magnetorheological seat has just been subjected to a large downward impact and is currently in the stage of releasing compression force, that is, the upward recovery stage. At this time, a larger anti-tensile damping force can be set according to actual needs, and the anti-tensile damping force is set as the initial damping value in this case.

[0153] 2. According to the vehicle body lateral acceleration, vehicle body vertical acceleration, and vehicle speed in the signal set, the corresponding initial damping value is increased or decreased to obtain the target mapping relationship.

[0154] It should be noted that in order to better adapt to different road conditions and working conditions, the above steps increase or decrease the initial damping value in combination with the lateral acceleration of the vehicle body, the vertical acceleration of the vehicle body, and the vehicle speed. The specific increase or decrease rules can be adjusted according to actual needs, or the initial damping value can be manually adjusted. The adjusted damping value is the damping force in the target mapping relationship.

[0155] For example: If the lateral acceleration of the vehicle body is large, it means that the vehicle may be in a sharp turn and the vehicle is in a turning state. Therefore, the corresponding initial damping value can be increased to enhance the stability of the seat and avoid seat shaking. If the vertical acceleration of the vehicle body is large, it means that the vehicle may be in a bumpy road. In this case, the corresponding initial damping value can be reduced to reduce vibration transmission and achieve a better shock absorption effect. If the vehicle speed is high, the corresponding initial damping value can be increased to effectively reduce the vibration amplitude of the vehicle body and absorb the vibration generated at a high speed, thereby improving passenger comfort and increasing stability.

[0156] In some embodiments, the vehicle CAN signal may also include other signals, such as an engine speed signal and an accelerator pedal position signal, which may be used to assist in determining road conditions and vehicle operating conditions.

[0157] The above embodiment adjusts the initial damping value by combining multiple factors, so as to obtain a target mapping relationship with higher accuracy and stronger adaptability.

[0158] In some embodiments, according to the target difference, the step of determining the target control current includes:

[0159] 1. Determine the product of the target difference and a preset first proportional gain as a first intermediate value.

[0160] 2. Integrate the target difference to obtain a second intermediate value, and determine the product of the second intermediate value and a preset first integral gain as a third intermediate value.

[0161] 3. Perform a differential operation on the target difference to obtain a fourth intermediate value, and determine the product of the fourth intermediate value and a preset first differential gain as the fifth intermediate value.

[0162] Fourth, the sum of the first intermediate value, the third intermediate value, and the fifth intermediate value is determined as the target control current.

[0163] It should be noted that by performing the above-mentioned PID (Proportional-Integral-Derivative Control) control, the accuracy and timeliness of the control process can be effectively improved.

[0164] In some embodiments, controlling the magnetorheological seat based on the target control current includes:

[0165] 1. Obtaining a second feedback current of the magnetorheological damper in the magnetorheological seat, and determining a difference between the target control current and the second feedback current as a value to be processed.

[0166] 2. Determine the product of the to-be-processed value and the preset second proportional gain as the sixth intermediate value.

[0167] 3. Integrate the value to be processed to obtain a seventh intermediate value, and determine the product of the seventh intermediate value and a preset second integral gain as the eighth intermediate value.

[0168] 4. Perform a differential operation on the value to be processed to obtain a ninth intermediate value, and determine the product of the ninth intermediate value and a preset second differential gain as the tenth intermediate value.

[0169] 5. Determine the sum of the sixth intermediate value, the eighth intermediate value, and the tenth intermediate value as the target duty cycle.

[0170] 6. Based on the target duty cycle, the magnetorheological damper is controlled.

[0171] It should be noted that by using PID to obtain the target duty cycle, the damping force output by the magnetorheological damper can be better controlled, the accuracy of the control process can be effectively improved, and the response speed is faster.

[0172] In order to avoid the magnetorheological damper overtravel during the control process, in some embodiments, a height threshold range is set to provide real-time protection for the magnetorheological seat.

[0173] In some embodiments, the method further comprises:

[0174] 1. Obtaining a height signal of the magnetorheological seat.

[0175] The height signal can be obtained by a preset seat height sensor.

[0176] 2. If the height of the magnetorheological seat exceeds a preset height threshold range, the magnetorheological damper in the magnetorheological seat is controlled based on a preset target current to increase the damping force output by the magnetorheological damper.

[0177] It can be understood that the target current is a relatively large current, thereby effectively increasing the damping force output by the magnetorheological damper to achieve real-time protection of the magnetorheological seat.

[0178] Figure 2 This is a flow chart of obtaining the target control current in the magnetorheological seat control method provided in one embodiment of the present application. Please refer to Figure 2 First, according to the first feedback current of the magnetorheological damper and the actual mapping relationship, the actual damping force is obtained. Secondly, the target signal set is preprocessed, such as filtering. Then, according to the preprocessed target signal set and the preset target mapping relationship, the target damping force is obtained. Finally, according to the difference between the actual damping force and the target damping force, PID operation is performed to obtain the target control current. In addition, during the entire control process, the height signal of the magnetorheological seat is obtained in real time. If the height of the magnetorheological seat exceeds the preset height threshold range, the preset EOT (End of Travel, travel limit controller) controller intervenes in the control, that is, the preset target current is determined as the target control current to increase the damping force output by the magnetorheological damper.

[0179] The magnetorheological seat control system provided by the present application is described below. The magnetorheological seat control system described below and the magnetorheological seat control method described above can be referenced to each other.

[0180] Figure 3 For a schematic diagram of the structure of a magnetorheological seat control system provided in one embodiment of the present application, please refer to Figure 3 The system comprises:

[0181] A signal acquisition module 310, configured to acquire a target signal set, wherein the target signal set includes an acceleration signal of a magnetorheological seat;

[0182] A target damping force acquisition module 320, configured to obtain a target damping force according to the target signal set and a preset target mapping relationship, wherein the target mapping relationship refers to a mapping relationship between a signal set and a damping force;

[0183] A target control current acquisition module 330 is used to determine the difference between the target damping force and the actual damping force of the magnetorheological seat as a target difference, and determine a target control current according to the target difference;

[0184] The control module 340 is used to control the magnetorheological seat based on the target control current. It should be noted that the magnetorheological seat control method provided in the above embodiment belongs to the same concept as the magnetorheological seat control system, and the specific manner in which each module performs the operation has been described in detail in the method embodiment and will not be repeated here. In actual applications, the magnetorheological seat control system provided in the above embodiment can assign the above functions to different functional modules as needed, that is, divide the internal structure of the system into different functional modules to complete all or part of the functions described above, and this is not limited here.

[0185] Figure 4 This is a schematic diagram of a practical application of a magnetorheological seat control system provided in an embodiment of the present application. Please refer to Figure 4 , in the actual application process, illustratively, it can be divided into three layers, namely, the perception layer, the decision layer, and the execution layer. The perception layer includes the vehicle CAN signal collector and multiple sensors, such as a seat height sensor and a seat speed sensor. The decision layer includes a signal acquisition module 310, a target damping force acquisition module 320, a target control current acquisition module 330, and a control module 340. The execution layer includes current execution modules of each magnetorheological damper (such as a left current execution module, a right current execution module, etc.), that is, a module for controlling the magnetorheological damper with a corresponding target control current. During the execution process, it is also used to feedback current, that is, to feed back the target control current to the decision layer for the next PID control to achieve PID closed-loop control.

[0186] This embodiment also provides a vehicle, comprising: the magnetorheological seat control system as described above. The vehicle can achieve the beneficial effects as described above.

[0187] It should be mentioned that the magnetorheological seat control method, system and vehicle in the above-mentioned embodiment can significantly improve the vibration isolation effect of the magnetorheological seat, that is, by performing dual PID control, it can respond quickly when the road conditions change, so as to quickly adjust the damping force of the magnetorheological seat, so that the seat responds to the road vibration more smoothly, significantly improves the riding comfort, and reduces the impact of vibration on the driver and passengers. In addition, the magnetorheological seat control method, system and vehicle can effectively improve the control accuracy and system stability, effectively maintain the appropriate damping force of the seat under extreme working conditions (such as high-speed driving, emergency braking, and bad road conditions, etc.), ensure the stability and control accuracy of the system in complex working conditions, and enable the magnetorheological seat to achieve the expected shock absorption effect more accurately.

[0188] Furthermore, the magnetorheological seat control method, system and vehicle can also reduce energy consumption and improve system efficiency. That is, by precisely controlling the current of the magnetorheological damper, unnecessary energy losses are reduced, so that the system can operate efficiently while meeting the comfort and stability requirements, thereby extending the service life of the equipment and further optimizing the overall energy efficiency of the vehicle.

[0189] In addition, the magnetorheological seat control method, system and vehicle can also improve user experience and health protection. It is understandable that long-term use of comfortable and stable magnetorheological seats can effectively reduce fatigue and health problems caused by vibration, improve the overall riding experience of passengers, and improve the driver's attention and driving safety, thereby bringing users a better user experience and body protection effect.

[0190] In some embodiments, an electronic device is also provided, which may be a server, and its internal structure is shown in FIG. Figure 5 As shown. The electronic device includes a processor, a memory, a network interface and a database connected via a system bus. The processor of the electronic device is used to provide computing and control capabilities. The memory of the electronic device includes a non-volatile and / or volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the electronic device is used to communicate with an external client via a network connection. When the computer program is executed by the processor, the functions or steps on the server side of the above method are implemented.

[0191] In some embodiments, an electronic device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the following steps when executing the computer program: obtaining a target signal set, the target signal set including an acceleration signal of a magnetorheological seat; obtaining a target damping force according to the target signal set and a preset target mapping relationship, the target mapping relationship referring to a mapping relationship between the signal set and the damping force; determining a difference between the target damping force and an actual damping force of the magnetorheological seat as a target difference, and determining a target control current according to the target difference; and controlling the magnetorheological seat based on the target control current.

[0192] In some embodiments, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented: obtaining a target signal set, the target signal set including an acceleration signal of a magnetorheological seat; obtaining a target damping force based on the target signal set and a preset target mapping relationship, the target mapping relationship referring to a mapping relationship between a signal set and the damping force; determining a difference between the target damping force and an actual damping force of the magnetorheological seat as a target difference, and determining a target control current based on the target difference; and controlling the magnetorheological seat based on the target control current.

[0193] It should be noted that the above functions or steps that can be implemented by the computer-readable storage medium or electronic device can refer to the relevant descriptions on the server side and the client side in the aforementioned method embodiment. To avoid repetition, they will not be described one by one here.

[0194] The flow chart and block diagram in the accompanying drawings illustrate the possible implementation architecture, function and operation of the method and computer program product according to various embodiments of the present disclosure. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment, or a part of a code, and the module, program segment, or a part of a code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some implementations as replacements, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0195] The above embodiments are merely illustrative of the principles and effects of the present application and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.

Claims

1. A magnetorheological seat control method, characterized in that: include: Acquire a target signal set, wherein the target signal set includes an acceleration signal of a magnetorheological seat; Obtaining a target damping force according to the target signal set and a preset target mapping relationship, wherein the target mapping relationship refers to a mapping relationship between the signal set and the damping force; Determining a difference between the target damping force and an actual damping force of the magnetorheological seat as a target difference, and determining a target control current according to the target difference; The magnetorheological seat is controlled based on the target control current.

2. The magnetorheological seat control method according to claim 1, characterized in that: The actual damping force is the damping force output by the magnetorheological damper in the magnetorheological seat, and the step of obtaining the actual damping force includes: Acquiring a first feedback current of the magnetorheological damper; The actual damping force is obtained according to the first feedback current and the preset actual mapping relationship, wherein the actual mapping relationship refers to the mapping relationship between the feedback current and the damping force, and the actual mapping relationship is obtained based on a preset data set, wherein the data set includes a plurality of sample points, and each of the sample points includes: a current value sample and a damping force sample of the magnetorheological damper, and the current value sample corresponds to the damping force sample.

3. The magnetorheological seat control method according to claim 2, characterized in that: The sample point also includes a relative motion speed, which refers to the motion speed of the piston of the magnetorheological damper relative to the cylinder of the magnetorheological damper. The current value sample, the damping force sample, and the relative motion speed in the sample point correspond to each other. The actual mapping relationship acquisition step includes: Using the plurality of sample points, calibrating the coefficients to be calibrated in the preset damping function to be calibrated, and determining the calibrated damping function to be calibrated as the actual mapping relationship; The dependent variable in the damping function to be calibrated is the damping force, and the independent variable expression in the damping function to be calibrated refers to the sum of the viscous damping term, the Coulomb friction force, and the current damping term, the viscous damping term refers to the product of the viscosity coefficient and the relative motion speed, the current damping term refers to the product of the damping coefficient and the current damping force, the current damping force is obtained by performing a hyperbolic tangent operation on the current proportional value, and the current proportional value refers to the product of the proportional coefficient and the current value, wherein the viscosity coefficient, the Coulomb friction force, the damping coefficient, and the proportional coefficient are all the coefficients to be calibrated.

4. The magnetorheological seat control method according to claim 3, characterized in that: Using the plurality of sample points to calibrate the coefficients to be calibrated in the preset damping function to be calibrated includes: Substituting the current value samples and the relative motion speed in the sample points into the damping function to be calibrated to obtain a damping force measurement value; determining a difference between the damping force measurement value and a corresponding damping force sample as a first error value; The coefficients to be calibrated are iterated based on the multiple first error values ​​to complete the calibration of the coefficients to be calibrated.

5. The magnetorheological seat control method according to claim 3, characterized in that: Using the plurality of sample points to calibrate the coefficients to be calibrated in the preset damping function to be calibrated includes: Substituting the damping force sample and the relative motion speed at the sample point into the damping function to be calibrated to obtain a current measurement value; determining a difference between the current measurement value and the corresponding current value sample as a second error value; The coefficient to be calibrated is iterated based on a plurality of the second error values ​​to complete calibration of the coefficient to be calibrated.

6. The magnetorheological seat control method according to claim 4, characterized in that: Iterating the coefficient to be calibrated based on the plurality of first error values ​​to complete calibration of the coefficient to be calibrated includes: Based on the plurality of the first error values, determining a first objective function, wherein a dependent variable expression of the first objective function is a sum of a plurality of target quantities, and the target quantity refers to a square value of the first error value; Calculating partial derivatives of each of the coefficients to be calibrated in the first objective function to obtain partial derivatives of each of the coefficients to be calibrated; Based on the partial derivatives, an update rule for each of the coefficients to be calibrated is obtained, wherein the update rule includes: determining the product of a preset learning rate and the partial derivative as an update term, and determining the difference between the original value of the coefficient to be calibrated and the corresponding update term as the update value of the current coefficient to be calibrated; Based on the update rule, the coefficients to be calibrated are iterated until the value of the first objective function is less than a preset convergence threshold or a preset number of iterations is reached to obtain a final value of each coefficient to be calibrated; and the final value of the coefficient to be calibrated is calibrated to the damping function to be calibrated.

7. The magnetorheological seat control method according to claim 1, characterized in that: The acceleration signal includes: a vertical acceleration signal and a lateral acceleration signal. The target signal set also includes: a whole vehicle CAN signal and a vertical velocity signal of a magnetorheological seat. The whole vehicle CAN signal includes the body lateral acceleration, body vertical acceleration, and vehicle speed of the vehicle in which the magnetorheological seat is located. The vertical velocity signal of the magnetorheological seat is obtained by integrating the vertical acceleration signal of the magnetorheological seat.

8. The magnetorheological seat control method according to claim 7, characterized in that: The step of obtaining the target mapping relationship includes: Acquire preset initial mapping information, the initial mapping information comprising: a signal set and an initial damping value, the signal set and the initial damping value are in one-to-one correspondence, wherein the initial damping value is positively correlated with the vertical velocity of the magnetorheological seat in the signal set; According to the vehicle body lateral acceleration, vehicle body vertical acceleration, and vehicle speed in the signal set, the corresponding initial damping value is increased or decreased to obtain the target mapping relationship.

9. The magnetorheological seat control method according to claim 1, characterized in that: According to the target difference, the step of determining the target control current includes: Determine a product of the target difference and a preset first proportional gain as a first intermediate value; Integrating the target difference to obtain a second intermediate value, and determining a product of the second intermediate value and a preset first integral gain as a third intermediate value; Performing a differential operation on the target difference to obtain a fourth intermediate value, and determining a product of the fourth intermediate value and a preset first differential gain as a fifth intermediate value; A sum of the first intermediate value, the third intermediate value, and the fifth intermediate value is determined as the target control current.

10. The magnetorheological seat control method according to claim 1 or 9, characterized in that: Based on the target control current, controlling the magnetorheological seat includes: Acquiring a second feedback current of a magnetorheological damper in the magnetorheological seat, and determining a difference between the target control current and the second feedback current as a value to be processed; Determine the product of the to-be-processed value and a preset second proportional gain as a sixth intermediate value; Integrating the value to be processed to obtain a seventh intermediate value, and determining the product of the seventh intermediate value and a preset second integral gain as an eighth intermediate value; Performing a differential operation on the value to be processed to obtain a ninth intermediate value, and determining a product of the ninth intermediate value and a preset second differential gain as a tenth intermediate value; determining a sum of the sixth intermediate value, the eighth intermediate value, and the tenth intermediate value as the target duty cycle; The magnetorheological damper is controlled based on the target duty cycle.

11. The magnetorheological seat control method according to claim 1, characterized in that: Also includes: Acquiring a height signal of the magnetorheological seat; If the height of the magnetorheological seat exceeds a preset height threshold range, the magnetorheological damper in the magnetorheological seat is controlled based on a preset target current to increase the damping force output by the magnetorheological damper.

12. A magnetorheological seat control system, characterized in that: include: A signal acquisition module, used to acquire a target signal set, wherein the target signal set includes an acceleration signal of a magnetorheological seat; A target damping force acquisition module, used to obtain a target damping force according to the target signal set and a preset target mapping relationship, wherein the target mapping relationship refers to a mapping relationship between a signal set and a damping force; a target control current acquisition module, configured to determine a difference between the target damping force and an actual damping force of the magnetorheological seat as a target difference, and determine a target control current according to the target difference; A control module is used to control the magnetorheological seat based on the target control current.

13. A vehicle, characterized in that: include: The magnetorheological seat control system as claimed in claim 12.

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