Disclosure of Invention
The application provides a control method and system for a magnetorheological seat and a vehicle, and aims to solve the problem that the damping force adjusting mode of the magnetorheological seat in the related art is difficult to adapt to a complex external environment, so that the comfort and stability of the magnetorheological seat are poor.
The application provides a control method of a magnetorheological seat, which comprises the steps of obtaining a target signal set, wherein the target signal set comprises acceleration signals of the magnetorheological seat;
Obtaining a target damping force according to the target signal set and a preset target mapping relation, wherein the target mapping relation refers to a mapping relation between the signal set and the damping force;
determining a difference value between the target damping force and the 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 controlling the magnetorheological seat based on the target control current.
In an embodiment of the present application, the actual damping force is a damping force output by a magnetorheological damper in the magnetorheological seat, and the step of obtaining the actual damping force includes:
Acquiring a first feedback current of the magneto-rheological damper;
The actual damping force is obtained according to the first feedback current and a preset actual mapping relation, wherein the actual mapping relation refers to a mapping relation between the feedback current and the damping force, the actual mapping relation is obtained based on a preset data set, the data set comprises a plurality of sample points, each sample point comprises a current value sample and a damping force sample of the magnetorheological damper, and the current value sample corresponds to the damping force sample.
In an embodiment of the present application, the sample point further includes a relative movement speed, where the relative movement speed refers to a movement speed of a piston of the magnetorheological damper relative to a cylinder of the magnetorheological damper, and the current value sample, the damping force sample, and the relative movement speed in the sample point correspond to each other, and the step of obtaining the actual mapping relationship includes:
Calibrating coefficients to be calibrated in a preset damping function to be calibrated by utilizing a plurality of sample points, and determining the calibrated damping function to be calibrated as the actual mapping relation;
The independent variable expression in the damping function to be calibrated refers to summation of a viscous damping term, coulomb friction force and a current damping term, the viscous damping term refers to the product between a viscous coefficient and a relative motion speed, the current damping term refers to the product between a damping coefficient and a current damping force, the current damping force is obtained by carrying out hyperbolic tangent operation on a current proportional value, and the current proportional value refers to the product between a proportional coefficient and a current value, wherein the viscous coefficient, the coulomb friction force, the damping coefficient and the proportional coefficient are all the coefficients to be calibrated.
In an embodiment of the present application, calibrating the coefficient to be calibrated in the preset damping function to be calibrated by using the plurality of sample points includes:
Substituting the current value sample and the relative movement speed in the sample point 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;
and iterating the coefficient to be calibrated based on the first error values to finish the calibration of the coefficient to be calibrated.
In an embodiment of the present application, calibrating the coefficient to be calibrated in the preset damping function to be calibrated by using the plurality of sample points includes:
Substituting the damping force sample and the relative movement speed in 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;
and iterating the coefficient to be calibrated based on the second error values to finish the calibration of the coefficient to be calibrated.
In an embodiment of the present application, iterating the coefficient to be calibrated based on the plurality of first error values to complete calibration of the coefficient to be calibrated includes:
Determining a first objective function based on a plurality of the first error values, the dependent variable expression of the first objective function being summing a plurality of target amounts, the target amounts being the square values of the first error values;
respectively calculating partial derivatives of each coefficient to be calibrated in the first objective function to obtain partial derivatives of each coefficient to be calibrated;
based on the partial derivatives, obtaining an updating rule of each coefficient to be calibrated, wherein the updating rule comprises the steps of determining a product between a preset learning rate and the partial derivatives as an updating item, and determining a difference value between an original value of the coefficient to be calibrated and the corresponding updating item as an updating value of the current coefficient to be calibrated;
and iterating the coefficients to be calibrated based on the updating rule until the value of the first objective function is smaller than a preset convergence threshold or the preset iteration times are reached to obtain the final value of each coefficient to be calibrated, and calibrating the final value of the coefficient to be calibrated to the damping function to be calibrated.
In an embodiment of the application, the acceleration signal comprises a vertical acceleration signal and a lateral acceleration signal, the target signal set further comprises a complete vehicle CAN signal and a vertical speed signal of the magnetorheological seat, the complete vehicle CAN signal comprises the lateral acceleration and the vertical acceleration of a vehicle body of the vehicle where the magnetorheological seat is located, and the vehicle speed, and the vertical speed signal of the magnetorheological seat is obtained by integrating the vertical acceleration signal of the magnetorheological seat.
In an embodiment of the present application, the step of obtaining the target mapping relationship includes:
Acquiring preset initial mapping information, wherein the initial mapping information comprises a signal set and a damping initial value, the signal set corresponds to the damping initial value one by one, and the damping initial value and the vertical speed of the magnetorheological seat in the signal set are in positive correlation;
And increasing or decreasing the corresponding damping initial value according to the lateral acceleration, the vertical acceleration and the vehicle speed of the vehicle body in the signal set so as to obtain the target mapping relation.
In an embodiment of the present application, the step of determining the target control current according to the target difference value includes:
Determining a product between the target difference value and a preset first proportional gain as a first intermediate value;
integrating the target difference value to obtain a second intermediate value, and determining the product between the second intermediate value and a preset first integral gain as a third intermediate value;
performing differential operation on the target difference value to obtain a fourth intermediate value, and determining the product between the fourth intermediate value and a preset first differential gain as a fifth intermediate value;
And determining a sum value among the first intermediate value, the third intermediate value, and the fifth intermediate value as the target control current.
In one embodiment of the present application, controlling the magnetorheological seat based on the target control current includes:
Acquiring a second feedback current of a magneto-rheological damper in the magneto-rheological seat, and determining a difference value between the target control current and the second feedback current as a value to be processed;
Determining the product between the value to be processed 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 between the seventh intermediate value and a preset second integral gain as an eighth intermediate value;
Performing differential operation on the value to be processed to obtain a ninth intermediate value, and determining the product between the ninth intermediate value and a preset second differential gain as a tenth intermediate value;
Determining a sum value between the sixth intermediate value, the eighth intermediate value, and the tenth intermediate value as the target duty cycle;
And controlling the magneto-rheological damper based on the target duty cycle.
In an embodiment of the present application, the method further includes:
acquiring a height signal of the magnetorheological seat;
And if the height of the magnetorheological seat exceeds a preset height threshold range, controlling the magnetorheological damper in the magnetorheological seat based on a preset target current so as to improve the damping force output by the magnetorheological damper.
The application also provides a magnetorheological seat control system, comprising:
the signal acquisition module is used for acquiring a target signal set, wherein the target signal set comprises acceleration signals of the magnetorheological seat;
The target damping force acquisition module is used for acquiring a target damping force according to the target signal set and a preset target mapping relation, wherein the target mapping relation refers to a mapping relation between the signal set and the damping force;
The target control current acquisition module is used for determining a difference value between the target damping force and the 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 the control module is used for controlling the magnetorheological seat based on the target control current.
The application also provides a vehicle comprising the magnetorheological seat control system.
The magnetorheological seat control method, the magnetorheological seat control system and the vehicle have the beneficial effects that the target signal set is obtained, the target signal set comprises acceleration signals of the magnetorheological seat, the target damping force is obtained according to the target signal set and the preset target mapping relation, the target mapping relation refers to the mapping relation between the signal set and the damping force, the difference between the target damping force and the actual damping force of the magnetorheological seat is determined as the target difference, the target control current is determined according to the target difference, the magnetorheological seat is controlled based on the target control current, and the method better realizes the self-adaptive adjustment of the damping force of the magnetorheological seat, namely, different target control currents can be obtained based on different acceleration signals of the magnetorheological seat, so that the damping force of the magnetorheological seat is controlled. 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 in which the magnetorheological seat is located), for example, if the vertical acceleration signal of the magnetorheological seat is larger and the lateral acceleration is larger, the vehicle may be on a bumpy road section and turn, etc. Therefore, by the method, the self-adaptive adjustment of the damping force of the magnetorheological seat in different external environments can be realized, and the comfort and stability of the magnetorheological seat are effectively improved.
Detailed Description
Other advantages and effects of the present application will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present application with reference to specific examples. The application may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present application. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict.
It should be noted that the illustrations provided in the following embodiments merely illustrate the basic concept of the present application by way of illustration, and only the components related to the present application are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complicated.
In the following description, numerous details are set forth in order to provide a more thorough explanation of embodiments of the present application, it will be apparent, however, to one skilled in the art that embodiments of the present application may be practiced without these specific details, in other embodiments, well-known structures and devices are shown in block diagram form, rather than in detail, in order to avoid obscuring the embodiments of the present application.
The magnetorheological seat control method, system and vehicle provided by the application are explained below with reference to fig. 1 to 5.
Referring to fig. 1, fig. 1 is a flow chart of a magnetorheological seat control method according to an embodiment of the application, as shown in fig. 1, the method includes:
s110, acquiring a target signal set, wherein the target signal set comprises acceleration signals of the magnetorheological seat.
It can be understood that by acquiring the acceleration signal of the magnetorheological seat, the road condition of the vehicle in which the magnetorheological seat is positioned and the current working condition of the vehicle can be conveniently determined, and then the corresponding damping force adjustment is performed.
S120, obtaining a target damping force according to the target signal set and a preset target mapping relation, wherein the target mapping relation refers to a mapping relation between the signal set and the damping force.
It can be understood that different signal sets in the target mapping relation correspond to different damping forces, and the target damping force is obtained based on the target mapping relation and the target signal set by setting the target mapping relation, so that the follow-up self-adaptive control of the damping force of the magnetorheological seat can be facilitated.
S130, determining a difference value between the target damping force and the actual damping force of the magnetorheological seat as a target difference value, and determining a target control current according to the target difference value.
It should be noted that, a mapping relationship between the target difference value and the control current may be preset, and a corresponding target control current may be obtained according to the target difference value and the mapping relationship.
And S140, controlling the magneto-rheological seat based on the target control current.
In examples of some embodiments, a corresponding current signal may be sent to a magnetorheological damper of the magnetorheological seat based on the target control current to complete control of the damping force output by the magnetorheological damper.
In some embodiments, the actual damping force is a damping force output by a magnetorheological damper in the magnetorheological seat, and the obtaining of the actual damping force includes:
1. And obtaining a first feedback current of the magneto-rheological damper.
2. The actual damping force is obtained according to the first feedback current and a preset actual mapping relation, wherein the actual mapping relation refers to a mapping relation between the feedback current and the damping force, the actual mapping relation is obtained based on a preset data set, the data set comprises a plurality of sample points, each sample point comprises a current value sample and a damping force sample of the magnetorheological damper, and the current value sample corresponds to the damping force sample.
It will be appreciated that by the above means, it is possible to facilitate the acquisition of the actual damping force of the magnetorheological damper. And, the actual mapping relation is obtained based on the preset data set, so that the accuracy is high.
In some examples of embodiments, when the data set is obtained, the determination of the actual mapping relationship may be completed by deep learning or other manners, for example, a current value sample in the data set is input into a preset neural network model to obtain a predicted damping force value output by the neural network model, and the neural network model is trained based on a difference between the predicted damping force value and a corresponding damping force sample until the model converges, where the obtained neural network model represents the actual mapping relationship.
In some embodiments, the sample point further includes a relative movement speed, where the relative movement speed refers to a movement speed of a piston of the magnetorheological damper relative to a cylinder of the magnetorheological damper, the current value sample, the damping force sample, and the relative movement speed in the sample point correspond to each other, and the step of obtaining the actual mapping relationship includes:
and calibrating coefficients to be calibrated in a preset damping function to be calibrated by utilizing a plurality of sample points, and determining the calibrated damping function to be calibrated as the actual mapping relation.
The independent variable expression in the damping function to be calibrated refers to summation of a viscous damping term, coulomb friction force and a current damping term, the viscous damping term refers to the product between a viscous coefficient and a relative motion speed, the current damping term refers to the product between a damping coefficient and a current damping force, the current damping force is obtained by carrying out hyperbolic tangent operation on a current proportional value, and the current proportional value refers to the product between a proportional coefficient and a current value, wherein the viscous coefficient, the coulomb friction force, the damping coefficient and the proportional coefficient are all the coefficients to be calibrated.
In the above embodiment, the damping function to be calibrated is determined by combining the viscous damping term, the coulomb friction and the current damping term, so that the damping function to be calibrated is higher in rationality, and the accuracy of the actual mapping relationship obtained later is improved conveniently.
In some embodiments, the mathematical expression of the damping function to be calibrated is:
Fd＝c1V+Fc+c2 tanh(kI)
Wherein Fd is a dependent variable of a damping function to be calibrated, namely damping force output by the magnetorheological damper, c1 v is a viscous damping term, c1 is a viscous coefficient which is related to a relative motion speed, v represents the relative motion speed, Fc represents coulomb friction force, c2 tanh (kI) is a current damping term, namely damping force generated by a magnetorheological nonlinear effect caused by current (controlling current of the magnetorheological damper), c2 represents the damping coefficient, tanh (kI) represents the current damping force, tanh (·) represents a hyperbolic tangent function, kI is a current proportional value, k represents a proportional coefficient, and I represents a current value.
In some embodiments, calibrating the coefficient to be calibrated in the preset damping function to be calibrated by using the plurality of sample points includes:
1. Substituting the current value sample and the relative movement speed in the sample point into the damping function to be calibrated to obtain a damping force measurement value.
2. A difference between the damping force measurement and the corresponding damping force sample is determined as a first error value.
Illustratively, assume that the mathematical expression of the sample point is (Ij,Fd,j,vj), where Ij represents the current value sample of the jth sample point, Fd,j represents the damping force sample of the jth sample point, and vj represents the relative movement speed of the jth sample point. Then, the mathematical expression of the first error value is:
ej1＝c1vj+Fc+c2 tanh(kIj)-Fd,j
wherein ej1 denotes the first error value.
3. And iterating the coefficient to be calibrated based on the first error values to finish the calibration of the coefficient to be calibrated.
It can be understood that an initial value is given to each coefficient to be calibrated, and then a current value sample and a relative movement speed in a sample point are substituted into the damping function to be calibrated, so as to obtain a damping force measurement value. And iterating the coefficients to be calibrated based on the difference between the damping force measured value and the corresponding damping force sample until the difference between the damping force measured value and the corresponding damping force sample is smaller than a preset convergence threshold or reaches the preset iteration times, thereby determining the final value of each coefficient to be calibrated, and calibrating the final value to the damping function to be calibrated. Through the mode, the calibration of the coefficient to be calibrated can be well completed, and the accuracy is high.
In some examples of embodiments, the coefficients to be calibrated may be iterated by way of dichotomy or the like.
In some embodiments, calibrating the coefficient to be calibrated in the preset damping function to be calibrated by using the plurality of sample points includes:
1. Substituting the damping force sample and the relative movement speed in the sample point into the damping function to be calibrated to obtain a current measurement value.
It can be understood that, by converting the mathematical expression of the damping function to be calibrated in the above embodiment, it is obtained that:
Wherein arctanh (. Cndot.) represents the inverse hyperbolic tangent function. And substituting the damping force sample and the relative movement speed in the sample point into the damping function to be calibrated, so that a current measurement value can be obtained.
Then substituting the damping force sample and the relative movement speed in the sample point into the mathematical expression to obtain a current measurement value
2. And determining a difference between the current measurement value and the corresponding current value sample as a second error value. The mathematical expression of the second error value is:
Wherein ej2 denotes the second error value.
3. And iterating the coefficient to be calibrated based on the second error values to finish the calibration of the coefficient to be calibrated.
It should be noted that, through adopting above-mentioned mode to accomplish the demarcation, the precision is higher.
In some embodiments, 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:
1. A first objective function is determined based on a plurality of the first error values, the dependent variable expression of the first objective function being summing a plurality of objective amounts, the objective amounts referring to square values of the first error values.
The mathematical expression of the first objective function is:
wherein G (c1,Fc,c2,k)1) represents the first objective function.
2. And respectively calculating partial derivatives of each coefficient to be calibrated in the first objective function to obtain the partial derivative of each coefficient to be calibrated.
3. And obtaining an updating rule of each coefficient to be calibrated based on the partial derivative, wherein the updating rule comprises the steps of determining a product between a preset learning rate and the partial derivative as an updating item, and determining a difference value between an original value of the coefficient to be calibrated and the corresponding updating item as an updating value of the current coefficient to be calibrated.
4. And iterating the coefficients to be calibrated based on the updating rule until the value of the first objective function is smaller than a preset convergence threshold or the preset iteration times are reached to obtain the final value of each coefficient to be calibrated, and calibrating the final value of the coefficient to be calibrated to the damping function to be calibrated.
By the method, the calibration of the coefficient to be calibrated can be well achieved, and the accuracy is high.
In some embodiments, iterating the coefficient to be calibrated based on the plurality of second error values to complete the calibration of the coefficient to be calibrated includes:
1. A second objective function is determined based on a plurality of the second error values, the dependent variable expression of the second objective function being summing a plurality of error values, the error values being the square of the second error values.
The mathematical expression of the second objective function is:
Wherein G (c1,Fc,c2,k)2) represents the second objective function.
2. And respectively calculating partial derivatives of each coefficient to be calibrated in the second objective function to obtain the partial derivative of each coefficient to be calibrated.
It should be noted that, in order to facilitate the subsequent application of the gradient descent method, the bias derivative is calculated for each coefficient to be calibrated in the second objective function, so as to obtain:
wherein G2 is G (c1,Fc,c2,k)2 is abbreviated,Representing a biasing of c1 in the second objective function.
Wherein,Representing a biasing of Fc in the second objective function.
Wherein,Representing a biasing of c2 in the second objective function.
Wherein,Representing a biasing of k in the second objective function.
3. And obtaining an updating rule of each coefficient to be calibrated based on the partial derivative, wherein the updating rule comprises the steps of determining a product between a preset learning rate and the partial derivative as an updating item, and determining a difference value between an original value of the coefficient to be calibrated and the corresponding updating item as an updating value of the current coefficient to be calibrated.
It should be noted that, in the gradient descent method, the parameter update formula of the second objective function is:
wherein θ represents the coefficient set { c1、Fc、c2、k},θi+1 to be calibrated for updating the coefficient to be calibrated, namely the updated value of the parameter to be calibrated, θi represents the current value of the coefficient to be calibrated, α represents the preset learning rate,And respectively carrying out deviation derivation on coefficients to be calibrated in the second objective function.
4. And iterating the coefficients to be calibrated based on the updating rule until the value of the first objective function is smaller than a preset convergence threshold or the preset iteration times are reached to obtain the final value of each coefficient to be calibrated, and calibrating the final value of the coefficient to be calibrated to the damping function to be calibrated.
It will be appreciated that the mathematical expression for updating c1 is:
Wherein,The updated value of c1 is represented,Representing the current value of c1 (the value before updating).
The mathematical expression for updating Fc is:
Wherein,The updated value of Fc is represented,Representing the current value of Fc (the value before updating).
The mathematical expression for updating c2 is:
Wherein,The updated value of c2 is represented,Representing the current value of c2 (the value before updating).
The mathematical expression for updating k is:
Where knew represents the updated value of k, and kold represents the current value of k (the value before update).
It can be appreciated that by the mode, the accurate value of each coefficient to be calibrated can be obtained.
In some embodiments, the acceleration signal comprises a vertical acceleration signal and a lateral acceleration signal, the target signal set further comprises a complete vehicle CAN signal and a vertical speed signal of the magnetorheological seat, the complete vehicle CAN signal comprises the lateral acceleration and the vertical acceleration of the vehicle body of the vehicle where the magnetorheological seat is located, and the vehicle speed, and the vertical speed signal of the magnetorheological seat is obtained by integrating the vertical acceleration signal of the magnetorheological seat.
In some embodiments, to avoid null shift of the vertical velocity signal, the vertical velocity signal may be high-pass filtered to eliminate interference of the low frequency signal.
It should be noted that, through gathering above-mentioned whole car CAN (Controller Area Network ) signal and magnetorheological seat's vertical speed signal, CAN be convenient for follow-up control in-process, accurate discernment road conditions and the operating mode etc. of vehicle.
In some embodiments, the obtaining the target mapping relationship includes:
1. The method comprises the steps of obtaining preset initial mapping information, wherein the initial mapping information comprises a signal set and a damping initial value, the signal set corresponds to the damping initial value one by one, and the damping initial value and the vertical speed of the magnetorheological seat in the signal set are in positive correlation.
It can be understood that each signal set includes a set of signals, that is, a vehicle body lateral acceleration, a vehicle body vertical acceleration, a vehicle speed, a vertical acceleration signal of the magnetorheological seat, a lateral acceleration signal, and the like, and each signal set corresponds to a damping initial value, so that the corresponding damping initial value can be adjusted based on the vehicle body lateral acceleration, the vehicle body vertical acceleration, the vehicle speed, and the like in the signal set. The damping initial value can be set according to actual conditions.
In some embodiments, the damping initial value may be set in two cases, one of which is to indicate that the magnetorheological seat is currently subjected to a larger downward impact when the vertical speed of the magnetorheological seat is smaller than the preset first speed threshold (usually negative), and at this time, a larger compressive damping force may be set according to the actual requirement, and the compressive damping force is set as the damping initial value in this case. Secondly, when the vertical speed of the magnetorheological seat is larger than a preset second speed threshold (usually positive), the magnetorheological seat is subjected to larger upward impact, or the magnetorheological seat is just subjected to larger downward impact, and the magnetorheological seat is currently in a compression force releasing, namely an upward recovery stage, so that larger tensile damping force can be set according to actual requirements at the moment, and the tensile damping force is set to be a damping initial value under the condition.
2. And increasing or decreasing the corresponding damping initial value according to the lateral acceleration, the vertical acceleration and the vehicle speed of the vehicle body in the signal set so as to obtain the target mapping relation.
It should be noted that, in order to better adapt to different road conditions and working conditions, the steps combine the lateral acceleration of the vehicle body, the vertical acceleration of the vehicle body, the vehicle speed and the like, increase or decrease the damping initial value, the specific rule of increasing or decreasing can be adjusted according to the actual requirement, and the damping initial value can also be manually adjusted, and the adjusted damping value is the damping force in the target mapping relation.
For example, if the lateral acceleration of the vehicle body is large, the vehicle is likely to be in a sharp turning road section and the vehicle is in a turning state at present, so that the corresponding damping initial value can be increased to enhance the stability of the seat, avoid the seat from shaking and the like. If the vertical acceleration of the vehicle body is larger, the fact that the vehicle is possibly positioned on a bumpy road section at present is indicated, corresponding damping initial values can be reduced, vibration transmission is reduced, and a better damping effect is achieved. If the vehicle speed is higher, the corresponding damping initial value can be increased, so that the vibration amplitude of the vehicle body is effectively reduced, the vibration generated when the vehicle speed is higher is absorbed, the comfort of passengers is improved, the stability is improved, and the like.
In some embodiments, the whole vehicle CAN signal may further include other signals, such as an engine speed signal, an accelerator pedal position signal, and the like, which may be used to assist in determining road conditions and vehicle conditions.
According to the embodiment, the damping initial value is adjusted by combining a plurality of factors, so that the target mapping relation with high accuracy and high adaptability can be obtained.
In some embodiments, the step of determining a target control current based on the target difference value comprises:
1. And determining the product of the target difference value and a preset first proportional gain as a first intermediate value.
2. And integrating the target difference value to obtain a second intermediate value, and determining the product between the second intermediate value and a preset first integral gain as a third intermediate value.
3. And performing differential operation on the target difference value to obtain a fourth intermediate value, and determining the product between the fourth intermediate value and a preset first differential gain as a fifth intermediate value.
4. And determining a sum value among the first intermediate value, the third intermediate value, and the fifth intermediate value as the target control current.
The accuracy and timeliness of the control process are effectively improved by performing the PID (Proportional-Integral-derivative) control.
In some embodiments, controlling the magnetorheological seat based on the target control current comprises:
1. And obtaining a second feedback current of the magnetorheological damper in the magnetorheological seat, and determining a difference value between the target control current and the second feedback current as a value to be processed.
2. And determining the product between the value to be processed and a preset second proportional gain as a sixth intermediate value.
3. And integrating the value to be processed to obtain a seventh intermediate value, and determining the product between the seventh intermediate value and a preset second integral gain as an eighth intermediate value.
4. And performing differential operation on the value to be processed to obtain a ninth intermediate value, and determining the product between the ninth intermediate value and a preset second differential gain as a tenth intermediate value.
5. And determining a sum value among the sixth intermediate value, the eighth intermediate value, and the tenth intermediate value as the target duty ratio.
6. And controlling the magneto-rheological damper based on the target duty cycle.
The target duty ratio is obtained through PID, so that the control of the damping force of the output of the magnetorheological damper can be well realized, the accuracy of the control process is effectively improved, and the response speed is high.
In order to avoid the situation that the magnetorheological damper overtravels in the control process, in some embodiments, the magnetorheological seat is protected in real time by setting a height threshold range.
In some embodiments, the method further comprises:
1. and acquiring a height signal of the magnetorheological seat.
The height signal may be obtained by a predetermined seat height sensor.
2. And if the height of the magnetorheological seat exceeds a preset height threshold range, controlling the magnetorheological damper in the magnetorheological seat based on a preset target current so as to improve the damping force output by the magnetorheological damper.
It can be understood that the target current is larger current, so that the damping force output by the magnetorheological damper is effectively improved, and the real-time protection of the magnetorheological seat is realized.
Fig. 2 is a schematic flow chart of obtaining a target control current in the magnetorheological seat control method according to an embodiment of the application, please refer to fig. 2, firstly, obtaining an actual damping force according to a first feedback current and an actual mapping relationship of the magnetorheological damper. Second, the target signal set is preprocessed, e.g., filtered, etc. And then, obtaining a target damping force according to the preprocessed target signal set and a preset target mapping relation. And finally, PID operation is carried out according to the difference value between the actual damping force and the target damping force, so as to obtain the target control current. And in the whole control process, a height signal of the magnetorheological seat is obtained in real time, if the height of the magnetorheological seat exceeds a preset height threshold range, a preset EOT (End of Travel) controller intervenes in control, namely, a preset target current is determined as a target control current, so that the damping force output by the magnetorheological damper is improved.
The magnetorheological seat control system provided by the application is described below, and the magnetorheological seat control system described below and the magnetorheological seat control method described above can be correspondingly referred to each other.
Fig. 3 is a schematic structural diagram of a magnetorheological seat control system according to an embodiment of the present application, please refer to fig. 3, wherein the system includes:
a signal acquisition module 310 for acquiring a set of target signals, the set of target signals including acceleration signals of the magnetorheological seat;
the target damping force obtaining module 320 is configured to obtain 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 the signal set and the damping force;
A target control current obtaining module 330, 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;
the control module 340 is configured to control the magnetorheological seat based on the target control current. It should be noted that, the magnetorheological seat control method and the magnetorheological seat control system provided in the above embodiments belong to the same concept, and the specific manner in which each module performs the operation has been described in detail in the method embodiment, which is not repeated herein. In practical application, the magnetorheological seat control system provided in the above embodiment may distribute the above functions to different functional modules according to needs, that is, the internal structure of the system is divided into different functional modules to complete all or part of the functions described above, which is not limited herein.
Fig. 4 is a schematic structural diagram of an actual application of the magnetorheological seat control system according to an embodiment of the present application, please refer to fig. 4, in which the actual application process is exemplarily divided into three layers, namely a sensing layer, a decision layer, and an executing layer. The sensing layer comprises a whole car CAN signal collector and a plurality of sensors, such as a seat height sensor, a seat speed sensor and the like. 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 comprises current execution modules (such as a left current execution module, a right current execution module and the like) of each magnetorheological damper, namely a module for controlling the magnetorheological damper by corresponding target control current, and is also used for feeding back the current in the execution process, namely feeding back the target control current to the decision layer for the next PID control, thereby realizing PID closed-loop control.
The embodiment also provides a vehicle, which comprises the magneto-rheological seat control system. The vehicle can achieve the advantageous effects as described above.
It should be noted that, the magnetorheological seat control method, the magnetorheological seat control system and the vehicle in the above embodiment can remarkably improve the vibration isolation effect of the magnetorheological seat, namely, through performing double PID control, the damping force of the magnetorheological seat can be quickly adjusted when the road condition changes, so that the response of the seat to the road vibration is more stable, the riding comfort is remarkably improved, and the influence of the vibration on a driver and passengers is reduced. In addition, the control method, the system and the vehicle of the magnetorheological seat can effectively improve the control precision and the system stability, effectively maintain the proper damping force of the seat under extreme working conditions (such as high-speed running, emergency braking, severe road conditions and the like), ensure the stability and the control precision of the system under complex working conditions, and enable the magnetorheological seat to achieve the expected damping effect more accurately.
Furthermore, the magnetorheological seat control method, the magnetorheological seat control system and the magnetorheological seat control vehicle can also reduce energy consumption, improve system efficiency, namely reduce unnecessary energy consumption loss by precisely controlling the current of the magnetorheological damper, ensure that the magnetorheological seat control system can efficiently operate on the premise of meeting comfort and stability requirements, prolong the service life of equipment and further optimize the overall energy efficiency of the vehicle.
In addition, the magnetorheological seat control method, the magnetorheological seat control system and the vehicle can also improve user experience and health protection, and it can be understood that the magnetorheological seat which is comfortable and stable for long-term use can effectively reduce fatigue and health problems caused by vibration, improve the overall riding experience of passengers and improve the attention and driving safety of drivers, thereby bringing better use experience and body protection effect for users.
In some embodiments, an electronic device is also provided, and the electronic device may be a service end, and an internal structure diagram of the electronic device is shown in fig. 5. The electronic device includes a processor, a memory, a network interface, and a database connected by a system bus. Wherein the processor of the electronic device is configured to provide computing and control capabilities. The memory of the electronic device includes non-volatile and/or volatile storage media and internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The network interface of the electronic device is used for communicating with an external client through a network connection. The computer program, when executed by a processor, performs the functions or steps of the method on the server side.
In some embodiments, an electronic device is provided, including a memory, a processor, and a computer program stored on the memory and operable on the processor, the processor executing the computer program to perform the steps of 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, determining a target control current according to the target difference, and controlling the magnetorheological seat based on the target control current.
In some embodiments, a computer readable storage medium is provided, on which a computer program is stored, which when executed by a processor performs the steps of obtaining a set of target signals, the set of target signals comprising acceleration signals of a magnetorheological seat, obtaining a target damping force according to the set of target signals and a preset target mapping relationship, the target mapping relationship referring to a mapping relationship between the set of signals 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, determining a target control current according to the target difference, and controlling the magnetorheological seat based on the target control current.
It should be noted that, the functions or steps that can be implemented by the computer readable storage medium or the electronic device may correspond to the descriptions of the server side and the client side in the foregoing method embodiments, and are not described herein one by one for avoiding repetition.
The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of methods and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
The above embodiments are merely illustrative of the principles of the present application and its effectiveness, and are not intended to limit the application. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the application. Accordingly, it is intended that all equivalent modifications and variations of the application be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.