CN115356932A - Servo control system and feedforward controller parameter setting method - Google Patents

Servo control system and feedforward controller parameter setting method Download PDF

Info

Publication number
CN115356932A
CN115356932A CN202211032538.1A CN202211032538A CN115356932A CN 115356932 A CN115356932 A CN 115356932A CN 202211032538 A CN202211032538 A CN 202211032538A CN 115356932 A CN115356932 A CN 115356932A
Authority
CN
China
Prior art keywords
feedforward controller
parameter
feedforward
rho
iteration
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202211032538.1A
Other languages
Chinese (zh)
Inventor
李敏
陈涛涛
金思芃
孙凡茗
刘恋奇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China University of Geosciences
Original Assignee
China University of Geosciences
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by China University of Geosciences filed Critical China University of Geosciences
Priority to CN202211032538.1A priority Critical patent/CN115356932A/en
Publication of CN115356932A publication Critical patent/CN115356932A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05BCONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B13/00Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion
    • G05B13/02Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric
    • G05B13/04Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators
    • G05B13/042Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators in which a parameter or coefficient is automatically adjusted to optimise the performance

Landscapes

  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Artificial Intelligence (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Evolutionary Computation (AREA)
  • Medical Informatics (AREA)
  • Software Systems (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Feedback Control In General (AREA)

Abstract

The invention relates to a servo control system and a parameter setting method of a feedforward controller, which comprises the following steps: an addition and subtraction arithmetic unit, a feedback controller, a feedforward controller, an addition arithmetic unit and a controlled object; the input end of the addition and subtraction arithmetic unit is connected with the output ends of the reference track and the controlled object so as to determine the track tracking error and output the track tracking error to the feedback controller; the feedback controller generates a feedback control signal based on the trajectory tracking error; the feedforward controller generates a feedforward control signal based on the reference trajectory; the output end of the feedback controller and the output end of the feedforward controller are connected with the input end of the addition arithmetic unit; the output end of the addition arithmetic unit is connected with the input end of the controlled object; and (3) the parameters of the feedforward controller are iteratively optimized according to the reference track and the track tracking error, and the iteration is stopped when the iteration termination condition is met. The servo control system and the feedforward controller parameter setting method do not need to establish a mathematical model of the controlled object, and can avoid the restriction of modeling errors on the servo performance.

Description

Servo control system and feedforward controller parameter setting method
Technical Field
The invention relates to the technical field of servo control, in particular to a servo control system and a parameter setting method of a feedforward controller.
Background
Servo control systems are of great importance in modern industrial applications. In servo control systems, the purpose of using a feedforward controller is to eliminate the tracking error introduced by the reference trajectory. Therefore, the reasonable design of the servo control system has important significance, and particularly, the parameterization method of the feedforward controller and the determination of the optimal parameters of the feedforward controller directly determine the trajectory tracking precision of the servo control system.
The existing design method of the feedforward controller generally adopts a model-based method, namely, the feedforward controller is designed according to an accurate model of a controlled object; although the feedforward controller is designed based on a model method, the feedforward controller is simple and practical, an accurate model of a controlled object needs to be obtained, and the requirement on modeling accuracy is high; particularly, for a controlled object with complex dynamic characteristics, it is expensive to obtain an accurate model, modeling errors are inevitable, implementation based on a model method is difficult, and effects are difficult to guarantee.
Disclosure of Invention
In view of the above, it is necessary to provide a servo control system and a method for tuning parameters of a feedforward controller.
A servo control system comprising: an addition and subtraction arithmetic unit, a feedback controller C, a feedforward controller F, an addition arithmetic unit and a controlled object P;
the input end of the addition and subtraction arithmetic unit is connected with the reference track r and the output end of the controlled object P; the output end of the addition and subtraction arithmetic unit is connected with the input end of the feedback controller C; the input end of the feedforward controller F is connected with a reference track r; the output end of the feedback controller C and the output end of the feedforward controller F are connected with the input end of the addition arithmetic unit; the output end of the addition arithmetic unit is connected with the input end of the controlled object P;
the addition and subtraction arithmetic unit obtains a reference track r and a position signal y output by a controlled object, determines a track tracking error e according to the difference value of the reference track r and the position signal y, and inputs the track tracking error e into the feedback controller C;
the feedback controller C generates a feedback control signal u based on the tracking error e c (ii) a The feedforward controller F generates a feedforward control based on the reference trajectory r and the feedforward controller parameter ρSignal u f (ii) a The parameter rho of the feedforward controller is iteratively optimized according to the reference track r and the track tracking error e, and when the iteration termination condition is met, the iteration is stopped, and the obtained parameter of the feedforward controller is an optimal parameter;
the addition operator acquires a feedback control signal u output by the feedback controller C c And a feedforward control signal u output by the feedforward controller F f Feedback control signal u c And a feedforward control signal u f Adding the signals to obtain a total control signal u, and outputting the total control signal u to a controlled object P;
and after receiving the master control signal u output by the addition arithmetic unit, the controlled object P outputs a position signal y and feeds the position signal y back to the addition and subtraction arithmetic unit.
A method of feedforward controller parameter tuning, the method comprising: a feedforward controller parameter optimization objective function J, a feedforward controller parameterization method, a feedforward controller parameter iteration optimization method and an iteration termination condition;
the feedforward controller parameter optimization objective function J is determined according to the actual control requirement of the servo control system, and the optimal parameter of the feedforward controller is determined by minimizing the feedforward controller parameter optimization objective function J;
the feedforward controller parameterization method expresses the feedforward controller F as a mathematical expression with respect to a finite number of parameters and basis functions;
according to the feedforward controller parameter iterative optimization method, updating a feedforward controller parameter rho by adopting an iterative optimization method according to a reference track r and a track tracking error e until an iteration termination condition is met;
the iteration termination condition is a basis for judging whether the parameter rho of the feedforward controller stops iteration, if the iteration termination condition is met, the iteration is stopped, the parameter optimization objective function J of the feedforward controller can be considered to reach the minimum value, and the obtained parameter of the feedforward controller is the optimal parameter; otherwise, continuing the iteration until the iteration termination condition is met.
The feedforward controller parameter optimization objective function J is the square sum of the track tracking error e, and the expression is as follows:
Figure BDA0003818038220000021
where N is the sample length.
The parameterization method of the feedforward controller comprises the following steps:
Figure BDA0003818038220000022
wherein z is a complex variable of the discrete transfer function; n and m are denominator polynomial order and numerator polynomial order respectively, and natural numbers are taken; feedforward controller parameter ρ = [ a = 1 ,…,a n ,b 0 ,…,b m ] T Containing denominator polynomial parameters a 1 ,…,a n And the numerator polynomial parameter b 0 ,…,b m
If there is an output delay in the controlled object P, the method for parameterizing the feedforward controller may be:
Figure BDA0003818038220000023
wherein d is the known output delay number of the controlled object P; feedforward controller parameter ρ = [ a = 1 ,…,a n ,b 0 ,…,b m ] T Containing a parameter a of a denominator polynomial 1 ,…,a n And the numerator polynomial parameter b 0 ,…,b m
If the controlled object P has a rigid body mode, the parameterization method of the feedforward controller can be as follows:
Figure BDA0003818038220000024
wherein, T s Sampling time of a servo control system; feedforward controller parameter ρ = [ a = 1 ,…,a n ,b 0 ,…,b m ] T Containing denominator polynomial parameters a 1 ,…,a n And the numerator polynomial parameter b 0 ,…,b m
The parameter iterative optimization method of the feedforward controller comprises the following steps:
Figure BDA0003818038220000025
wherein j is the number of iterations; λ is learning rate, and is between 0 and 1;
Figure BDA0003818038220000026
optimizing the first derivative of the objective function J on the feedforward controller parameter p at p for the feedforward controller parameter j Taking the value of (A);
Figure BDA0003818038220000027
optimizing the Hessian matrix of the objective function J to the feedforward controller parameter rho at rho for the feedforward controller parameter j The value of (c) is as follows.
The method for setting the parameters of the feedforward controller comprises the following specific steps:
initializing, enabling the iteration times j =0, and setting an initial parameter rho of a feedforward controller F 0
Step two, in the feed forward controller F = F (rho) j Z) performing the j-th track following task, and recording the track following error e j
Step three, estimating a first derivative of a feedforward controller parameter optimization objective function J to a feedforward controller parameter rho to be in rho j Value of (a)
Figure BDA0003818038220000028
Step four, estimating the Hessian matrix of the feedforward controller parameter optimization objective function J to the feedforward controller parameter rho at rho j Inverse of the value of
Figure BDA0003818038220000029
Step five, according to the parameter iteration optimization method of the feedforward controllerUpdating feedforward controller parameters to obtain rho j+1
Step six, in the feed forward controller F = F (rho) j+1 Z) performing the j +1 th track following task, and recording the track following error e j+1
Step seven, judging whether the result of the J +1 th track tracking task meets the iteration termination condition, if so, stopping the iteration, considering that the parameter optimization objective function J of the feedforward controller reaches the minimum value, and obtaining the parameter rho of the feedforward controller j+1 Is an optimal parameter; otherwise, let j = j +1, jump to step three.
Initial parameter ρ of the feedforward controller F 0 May be set to zero.
If the controlled object P has rigid body mode and the nominal quality is known, adopting the parameterization method of the feedforward controller in claim 6, and setting the initial parameter P of the feedforward controller F 0 When b is greater than b 0 Is set as the reciprocal of the nominal mass of the controlled object, and the initial values of other parameters are set as zero.
The first derivative of the feedforward controller parameter optimization objective function J to the feedforward controller parameter rho is in rho j Value of (A)
Figure BDA0003818038220000031
The estimation method comprises the following steps:
first derivative of the feedforward controller F on the feedforward controller parameter p
Figure BDA0003818038220000032
The product of the reference trajectory r is denoted as gamma; setting the reference track r of the servo control system to be zero, and setting the track tracking error e j Adding the processed signal to the input end of the controlled object after the inverse sequence processing, recording the position signal y of the output end of the controlled object, and recording the result of the inverse sequence processing of the position signal y as Λ j ;-2Γ T Λ j Is that
Figure BDA0003818038220000033
The feedforward controller parameterOptimizing Hessian matrix of an objective function J to a feedforward controller parameter rho at rho j Inverse of the value of
Figure BDA0003818038220000034
The estimation method comprises the following steps:
note B j Optimizing an objective function J for the feedforward controller parameter and a Hessian matrix of the feedforward controller parameter rho at rho j Inverse of the value of
Figure BDA0003818038220000035
When j =0, B 0 Is a unit matrix; when j is not equal to 0, calculating the parameter rho of the j iteration feedforward controller j With the (j-1) th iteration feedforward controller parameter p j-1 Is recorded as Δ j (ii) a Calculating the first derivative of the jth iteration feedforward controller parameter optimization objective function J to the feedforward controller parameter rho at rho j Value of (A)
Figure BDA0003818038220000036
The first derivative of the parameter optimization objective function J of the feedforward controller on the parameter rho of the feedforward controller in the J-1 th iteration feedforward controller is in the rho j-1 Value of (a)
Figure BDA0003818038220000037
Is marked as ζ j ;B j The estimation method comprises the following steps:
Figure BDA0003818038220000038
the iteration termination condition may be:
Figure BDA0003818038220000039
wherein epsilon is more than or equal to 0 and is determined according to the actual control requirement of the servo control system.
The iteration termination condition may also be:
Figure BDA00038180382200000310
wherein tau is more than or equal to 0 and is determined according to the actual control requirement of the servo control system.
The servo control system comprises an addition and subtraction arithmetic unit, a feedback controller, a feedforward controller, an addition arithmetic unit and a controlled object, wherein parameters of the feedforward controller are iteratively optimized according to a reference track and a track tracking error, and iteration is stopped when an iteration termination condition is met. The servo control system is designed and a track tracking task is carried out, parameters of the feedforward controller are iteratively optimized according to a reference track and a track tracking error, so that the optimal parameters of the feedforward controller are obtained, and the constraint of a modeling error on the servo performance can be avoided because the servo control system and the parameter setting method of the feedforward controller do not need to establish a mathematical model of a controlled object.
Drawings
FIG. 1 is a schematic diagram of a servo control system according to an embodiment of the present invention;
FIG. 2 is a schematic flow chart of a method for tuning parameters of a feedforward controller according to an embodiment of the present invention;
FIG. 3 is a bode diagram of a controlled object in accordance with an embodiment of the present invention;
FIG. 4 is a diagram illustrating a fourth-order reference trajectory used in performing a trajectory tracking task in accordance with an embodiment of the present invention;
FIG. 5 is a diagram illustrating the convergence of the feedforward controller parameter optimization objective function J according to an embodiment of the present invention;
FIG. 6 is a graph showing a comparison of trajectory tracking errors for the same trajectory tracking task using the method of the present invention and a feedforward controller designed based on a model method in accordance with an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
As shown in fig. 1, the servo control system in this embodiment includes: an addition and subtraction arithmetic unit, a feedback controller C, a feedforward controller F, an addition arithmetic unit and a controlled object P;
the input end of the addition and subtraction arithmetic unit is connected with the reference track r and the output end of the controlled object P; the output end of the addition and subtraction arithmetic unit is connected with the input end of the feedback controller C; the input end of the feedforward controller F is connected with a reference track r; the output end of the feedback controller C and the output end of the feedforward controller F are connected with the input end of the addition arithmetic unit; the output end of the addition arithmetic unit is connected with the input end of the controlled object P;
the addition and subtraction arithmetic unit obtains a reference track r and a position signal y output by a controlled object, determines a track tracking error e according to the difference value of the reference track r and the position signal y, and inputs the track tracking error e into the feedback controller C;
the feedback controller C generates a feedback control signal u based on the tracking error e c (ii) a The feedforward controller F generates a feedforward control signal u based on the reference trajectory r and the feedforward controller parameter ρ f
The addition operator obtains a feedback control signal u output by the feedback controller C c And a feedforward control signal u output by the feedforward controller F f Feeding back the control signal u c And a feedforward control signal u f Adding the signals to obtain a master control signal u, and outputting the master control signal u to a controlled object P;
and after receiving the total control signal u output by the addition arithmetic unit, the controlled object P outputs a position signal y, and the position signal y is fed back to the addition and subtraction arithmetic unit.
In this embodiment, the feedforward controller parameter optimization objective function J is the sum of squares of the trajectory tracking error e, and the expression is:
Figure BDA0003818038220000041
where N is the sample length.
In this embodiment, as shown in fig. 3, the bode diagram of the controlled object P is, since the controlled object P has a rigid body mode, the parameterization method of the feedforward controller is selected as follows:
Figure BDA0003818038220000042
wherein z is a complex variable of the discrete transfer function; t is s In this embodiment, 0.0002s is taken as the sampling time of the servo control system; n and m are denominator polynomial order and numerator polynomial order, respectively, 0 and 4 being taken in this embodiment; feedforward controller parameter ρ = [ b ] 0 ,…,b 4 ] T
The parameter iteration optimization method of the feedforward controller in the embodiment comprises the following steps:
Figure BDA0003818038220000043
wherein j is the number of iterations; λ is learning rate, which is 0.8 in this example;
Figure BDA0003818038220000044
optimizing the first derivative of the objective function J on the feedforward controller parameter p at p for the feedforward controller parameter j Taking the value of (A);
Figure BDA0003818038220000045
optimizing the Hessian matrix of the objective function J to the feedforward controller parameter rho at rho for the feedforward controller parameter j The value of (c).
Fig. 4 shows a fourth-order reference trajectory used for the trajectory tracking task in this embodiment.
In this embodiment, since the controlled object P has a rigid body mode and the nominal mass is known, the initial parameter ρ of the feedforward controller F is set 0 When b is greater than b 0 Is set as the reciprocal of the nominal mass of the controlled object, and the initial values of other parameters are set as zero.
In the embodiment, the first derivative of the feedforward controller parameter optimization objective function J to the feedforward controller parameter rho is in rho j Value of (a)
Figure BDA0003818038220000051
The estimation method comprises the following steps:
first derivative of feedforward controller F on feedforward controller parameter p
Figure BDA0003818038220000052
The product of the reference trajectory r is denoted as gamma; setting the reference track r of the servo control system to be zero, and setting the track tracking error e j Adding the processed signal to the input end of the controlled object after the inverse sequence processing, recording the position signal y of the output end of the controlled object, and recording the result of the inverse sequence processing of the position signal y as Λ j ;-2Γ T Λ j Is that
Figure BDA0003818038220000053
In the embodiment, the Hessian matrix of the parameter optimization objective function J of the feedforward controller to the parameter rho of the feedforward controller is in rho j Inverse of the value of
Figure BDA0003818038220000054
The estimation method comprises the following steps:
note B j Optimizing an objective function J for the feedforward controller parameter and a Hessian matrix of the feedforward controller parameter rho at rho j Inverse of the value of
Figure BDA0003818038220000055
When j =0, B 0 Is an identity matrix; when j is not equal to 0, calculating the parameter rho of the j iteration feedforward controller j With the (j-1) th iteration feedforward controller parameter p j-1 Is recorded as Δ j (ii) a Calculating the first derivative of the jth iteration feedforward controller parameter optimization objective function J to the feedforward controller parameter rho at rho j Value of (A)
Figure BDA0003818038220000056
The first derivative of the parameter optimization objective function J of the feedforward controller on the parameter rho of the feedforward controller in the J-1 th iteration feedforward controller is in the rho j-1 Value of (A)
Figure BDA0003818038220000057
Is marked as ζ j ;B j The calculating method comprises the following steps:
Figure BDA0003818038220000058
the iteration termination condition in this embodiment is:
Figure BDA0003818038220000059
wherein ε is not less than 0, in this example 1X 10 -5
The method for setting the parameters of the feedforward controller in the embodiment specifically comprises the following steps:
initializing, enabling the iteration number j =0, and setting an initial parameter rho of a feedforward controller 0
Step two, in the feedforward controller F = F (rho) j Z) performing the j-th track following task, and recording the track following error e j
Estimating the first derivative of the feedforward controller parameter optimization objective function J to the feedforward controller parameter rho at rho j Value of (A)
Figure BDA00038180382200000510
Step four, estimating the Hessian matrix of the feedforward controller parameter optimization objective function J to the feedforward controller parameter rho at rho j Inverse of the value of
Figure BDA00038180382200000511
Step five, updating the parameters of the feedforward controller according to the parameter iterative optimization method of the feedforward controller to obtain rho j+1
Step six, in the feed forward controller F = F (rho) j+1 Z) performing the j +1 st track following task, and recording the track following error e j+1
Step seven, judging whether the result of the J +1 th track tracking task meets the iteration termination condition, if so, stopping the iteration, considering that the parameter optimization objective function J of the feedforward controller reaches the minimum value, and obtaining the parameter rho of the feedforward controller j+1 Is an optimal parameter; otherwise, let j = j +1, jump to step three.
In this embodiment, with the tuning of the feedforward controller parameter, the convergence condition of the feedforward controller parameter optimization objective function J is as shown in fig. 5, the feedforward controller parameter optimization objective function J gradually converges, and the iteration termination condition is already satisfied during the 6 th iteration, and the iteration can be stopped.
The application result of the method of the present invention in this embodiment is shown in fig. 6, and compared with the existing feedforward controller designed based on the model method, when the same trajectory tracking task is performed, the method of the present invention has the advantages of small trajectory tracking error, high trajectory tracking precision, and can effectively realize the high-performance motion control of the servo control system.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that several changes and modifications may be made without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A servo control system comprising: an addition and subtraction arithmetic unit, a feedback controller C, a feedforward controller F, an addition arithmetic unit and a controlled object P;
the input end of the addition and subtraction arithmetic unit is connected with the reference track r and the output end of the controlled object P; the output end of the addition and subtraction arithmetic unit is connected with the input end of the feedback controller C; the input end of the feedforward controller F is connected with a reference track r; the output end of the feedback controller C and the output end of the feedforward controller F are connected with the input end of the addition arithmetic unit; the output end of the addition arithmetic unit is connected with the input end of the controlled object P;
the addition and subtraction arithmetic unit obtains a reference track r and a position signal y output by a controlled object, determines a track tracking error e according to the difference value of the reference track r and the position signal y, and inputs the track tracking error e into the feedback controller C;
the feedback controller C generates a feedback control signal u based on the tracking error e c (ii) a The feedforward controller F generates a feedforward control signal u based on the reference trajectory r and the feedforward controller parameter ρ f (ii) a The parameter rho of the feedforward controller is iteratively optimized according to the reference track r and the track tracking error e, iteration is stopped when an iteration termination condition is met, and the obtained parameter of the feedforward controller is an optimal parameter;
the addition operator acquires a feedback control signal u output by the feedback controller C c And a feedforward control signal u output by the feedforward controller F f Feeding back the control signal u c And a feedforward control signal u f Adding the signals to obtain a master control signal u, and outputting the master control signal u to a controlled object P;
and after receiving the master control signal u output by the addition arithmetic unit, the controlled object P outputs a position signal y and feeds the position signal y back to the addition and subtraction arithmetic unit.
2. A method of feedforward controller parameter tuning, the method comprising: a feedforward controller parameter optimization objective function J, a feedforward controller parameterization method, a feedforward controller parameter iteration optimization method and an iteration termination condition;
the feedforward controller parameter optimization objective function J is determined according to the actual control requirement of the servo control system, and the optimal parameter of the feedforward controller is determined by minimizing the feedforward controller parameter optimization objective function J;
the feedforward controller parameterization method represents the feedforward controller F as a mathematical expression on a finite number of parameters and basis functions;
according to the feedforward controller parameter iterative optimization method, updating a feedforward controller parameter rho by adopting an iterative optimization method according to a reference track r and a track tracking error e until an iteration termination condition is met;
the iteration termination condition is a basis for judging whether the parameter rho of the feedforward controller stops iteration, if the iteration termination condition is met, the iteration is stopped, the parameter optimization objective function J of the feedforward controller can be considered to reach the minimum value, and the obtained parameter of the feedforward controller is the optimal parameter; otherwise, continuing the iteration until the iteration termination condition is met.
3. A feedforward controller parameter setting method according to claim 2, characterized in that the feedforward controller parameter optimization objective function J is a sum of squares of a trajectory tracking error e, and the expression is:
Figure FDA0003818038210000011
where N is the sample length.
4. A feedforward controller parameter setting method according to claim 2, wherein the feedforward controller parameterization method is:
Figure FDA0003818038210000012
wherein z is a complex variable of the discrete transfer function; n and m are denominator polynomial order and numerator polynomial order respectively, and natural numbers are taken; feedforward controller parameter ρ = [ a = 1 ,…,a n ,b 0 ,…,b m ] T Containing denominator polynomial parameters a 1 ,…,a n And the numerator polynomial parameter b 0 ,…,b m
If there is an output delay in the controlled object P, the method for parameterizing the feedforward controller may be:
Figure FDA0003818038210000021
wherein d is the known output delay number of the controlled object P; feedforward controller parameter ρ = [ a = 1 ,…,a n ,b 0 ,…,b m ] T Containing denominator polynomial parameters a 1 ,…,a n And the numerator polynomial parameter b 0 ,…,b m
If the controlled object P has a rigid body mode, the feedforward controller parameterization method may be:
Figure FDA0003818038210000022
wherein, T s Sampling time of a servo control system; feedforward controller parameter ρ = [ a = 1 ,…,a n ,b 0 ,…,b m ] T Containing denominator polynomial parameters a 1 ,…,a n And the numerator polynomial parameter b 0 ,…,b m
5. A feedforward controller parameter setting method according to claim 2, characterized in that the feedforward controller parameter iterative optimization method is:
Figure FDA0003818038210000023
wherein j is the number of iterations; λ is learning rate, and is between 0 and 1;
Figure FDA0003818038210000024
optimizing the first derivative of the objective function J on the feedforward controller parameter p at p for the feedforward controller parameter j Taking the value of (A);
Figure FDA0003818038210000025
optimizing the Hessian matrix of the objective function J to the feedforward controller parameter rho at rho for the feedforward controller parameter j The value of (c) is as follows.
6. A method for tuning parameters of a feedforward controller according to claim 2, characterized by comprising the following steps:
initializing, enabling the iteration number j =0, and setting an initial parameter rho of a feedforward controller F 0
Step two, in the feedforward controller F = F (rho) j Z) performing the j-th track following task, and recording the track following error e j
Estimating the first derivative of the feedforward controller parameter optimization objective function J to the feedforward controller parameter rho at rho j Value of (A)
Figure FDA0003818038210000026
Step four, estimating the Hessian matrix of the feedforward controller parameter optimization objective function J to the feedforward controller parameter rho at rho j Inverse of the value of
Figure FDA0003818038210000027
Fifthly, updating the parameters of the feedforward controller according to the parameter iterative optimization method of the feedforward controller to obtain rho j+1
Step six, in the feed forward controller F = F (rho) j+1 Z) performing the j +1 st track following task, and recording the track following error e j +1
Step seven, judging whether the result of the J +1 th track tracking task meets the iteration termination condition, if so, stopping the iteration, considering that the parameter optimization objective function J of the feedforward controller reaches the minimum value, and obtaining the parameter rho of the feedforward controller j+1 Is the optimal parameter; otherwise, let j = j +1, jump to step three.
7. A feedforward controller parameter setting method according to claim 8, characterized in that the initial parameter ρ of the feedforward controller F 0 May be set to zero. If the object P has rigid body mode and the nominal quality is known, the feedforward controller parameterization method of claim 6 is adopted, and the method is used for the step of determining the feedforward controller parameterizationSetting an initial parameter ρ of a feedforward controller F 0 When b is greater than 0 Is set as the reciprocal of the nominal mass of the controlled object, and the initial values of other parameters are set as zero.
8. A feedforward controller parameter tuning method according to claim 8, wherein the first derivative of the feedforward controller parameter optimization objective function J on the feedforward controller parameter ρ is at ρ j Value of (A)
Figure FDA0003818038210000028
The estimation method comprises the following steps:
first derivative of the feedforward controller F on the feedforward controller parameter p
Figure FDA0003818038210000029
The product of the reference trajectory r is denoted as gamma; setting the reference track r of the servo control system to be zero, and setting the track tracking error e j Adding the processed signal to the input end of the controlled object after the inverse sequence processing, recording the position signal y of the output end of the controlled object, and recording the result of the inverse sequence processing of the position signal y as Λ j ;-2Γ T Λ j Is that
Figure FDA00038180382100000210
9. A feedforward controller parameter setting method according to claim 8, characterized in that the Hessian matrix of the feedforward controller parameter optimization objective function J to the feedforward controller parameter p is at p j Inverse of the value of
Figure FDA00038180382100000211
The estimation method comprises the following steps:
note B j Optimizing the Hessian matrix of the objective function J to the feedforward controller parameter rho at rho for the feedforward controller parameter j Inverse of the value of
Figure FDA00038180382100000212
When j =0, B 0 Is an identity matrix; when j is not equal to 0, calculating the parameter rho of the j iteration feedforward controller j With the (j-1) th iteration feedforward controller parameter p j-1 Is recorded as Δ j (ii) a Calculating the first derivative of the jth iteration feedforward controller parameter optimization objective function J to the feedforward controller parameter rho at rho j Value of (A)
Figure FDA0003818038210000031
The first derivative of the parameter optimization objective function J of the feedforward controller on the parameter rho of the feedforward controller in the J-1 th iteration feedforward controller is in the rho j-1 Value of (A)
Figure FDA0003818038210000032
Is marked as ζ j ;B j The estimation method comprises the following steps:
Figure FDA0003818038210000033
10. a feedforward controller parameter tuning method according to claim 2 and claim 8, wherein the iteration end condition may be:
Figure FDA0003818038210000034
wherein epsilon is more than or equal to 0 and is determined according to the actual control requirement of the servo control system.
The iteration termination condition may also be:
Figure FDA0003818038210000035
wherein tau is more than or equal to 0 and is determined according to the actual control requirement of the servo control system.
CN202211032538.1A 2022-08-26 2022-08-26 Servo control system and feedforward controller parameter setting method Pending CN115356932A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202211032538.1A CN115356932A (en) 2022-08-26 2022-08-26 Servo control system and feedforward controller parameter setting method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202211032538.1A CN115356932A (en) 2022-08-26 2022-08-26 Servo control system and feedforward controller parameter setting method

Publications (1)

Publication Number Publication Date
CN115356932A true CN115356932A (en) 2022-11-18

Family

ID=84005573

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202211032538.1A Pending CN115356932A (en) 2022-08-26 2022-08-26 Servo control system and feedforward controller parameter setting method

Country Status (1)

Country Link
CN (1) CN115356932A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116678605A (en) * 2023-06-09 2023-09-01 哈尔滨工业大学 Soft measurement system and method for quality-damping-rigidity characteristics of precision motion platform

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110221541A (en) * 2019-05-31 2019-09-10 固高科技(深圳)有限公司 The feed-forward coefficients acquisition device of feedforward controller, method in servo-system
US20200278686A1 (en) * 2019-02-28 2020-09-03 University Of South Carolina Iterative Feedback Motion Planning
CN112612211A (en) * 2020-12-24 2021-04-06 浙江理工大学 Servo system residual vibration suppression method based on parametric feedforward
WO2022012156A1 (en) * 2020-07-14 2022-01-20 江南大学 Iterative feedback tuning control for rotating inverted pendulum and robust optimisation method therefor
CN115599044A (en) * 2022-10-28 2023-01-13 中国地质大学(武汉)(Cn) Double-loop iterative learning feedforward control system and method for servo motion system

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200278686A1 (en) * 2019-02-28 2020-09-03 University Of South Carolina Iterative Feedback Motion Planning
CN110221541A (en) * 2019-05-31 2019-09-10 固高科技(深圳)有限公司 The feed-forward coefficients acquisition device of feedforward controller, method in servo-system
WO2022012156A1 (en) * 2020-07-14 2022-01-20 江南大学 Iterative feedback tuning control for rotating inverted pendulum and robust optimisation method therefor
CN112612211A (en) * 2020-12-24 2021-04-06 浙江理工大学 Servo system residual vibration suppression method based on parametric feedforward
CN115599044A (en) * 2022-10-28 2023-01-13 中国地质大学(武汉)(Cn) Double-loop iterative learning feedforward control system and method for servo motion system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
MIN LI , JIAXI XIONG, RONG CHENG, YU ZHU , KAIMING YANG , AND FANMING SUN: "Rational Feedforward Tuning Using Variance-Optimal Instrumental Variables Method Based on Dual-Loop Iterative Learning Control", IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS, vol. 19, no. 3, 12 April 2022 (2022-04-12), pages 1 - 14 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116678605A (en) * 2023-06-09 2023-09-01 哈尔滨工业大学 Soft measurement system and method for quality-damping-rigidity characteristics of precision motion platform
CN116678605B (en) * 2023-06-09 2023-11-07 哈尔滨工业大学 Soft measurement system and method for quality-damping-rigidity characteristics of precision motion platform

Similar Documents

Publication Publication Date Title
Shen et al. Survey on stochastic iterative learning control
WO2018151215A1 (en) Control device and control method
CN110221541B (en) Feedforward coefficient acquisition device and method of feedforward controller in servo system
CN115356932A (en) Servo control system and feedforward controller parameter setting method
Janot et al. An instrumental variable approach for rigid industrial robots identification
Chen et al. Augmented Taylor's expansion method for B-spline curve interpolation for CNC machine tools
KR20120098203A (en) Pid control method of changing parameters adaptively and apparatus thereof
Teng et al. Lie algebraic cost function design for control on Lie groups
Hillenbrand et al. An iterative learning controller with reduced sampling rate for plants with variations of initial states
Dong et al. Interpolating gain-scheduled H∞ loop shaping design for high speed ball screw feed drives
CN115599044A (en) Double-loop iterative learning feedforward control system and method for servo motion system
Vasu et al. Internal model control design based on approximation of linear discrete dynamical systems
CN113641193B (en) Accurate tracking control method for non-minimum phase system
CN115238454A (en) Method and device for correcting data
CN108107722B (en) Decoupling control method for MIMO based on SISO bias format model-less controller and system error
Mooren et al. Feedforward motion control: From batch-to-batch learning to online parameter estimation
CN114153148A (en) Gradient iteration feedforward setting method with variable learning step length
CN113985887A (en) Method for generating motion trail of differential mobile robot and motion control device
CN115248554A (en) Optimal iteration feedforward parameter adjusting method and system for motion control system
CN115867870A (en) Using generalized homogeneity to improve PID control commands
CN117484499B (en) SCARA robot for tracking robust track of mechanical arm
Short A simplified approach to multivariable model predictive control
CN108107721B (en) Decoupling control method for MIMO based on SISO bias format model-free controller and bias information
TWI679507B (en) Learning system and method for controlling dual-axis machine tool with equivalent contour error
CN116774585B (en) Nano-precision motion table learning control system and method

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination