Control of Linear Motors for Machine Tool Feed Drives: Experimental Investigation of Optimal Feedforward Tracking Control

This paper investigates the use of optimal l1 and H∞ model reference optimal feedforward control to enhance the tracking performance of a linear motor drive. Experimental work is presented which studies the effects of signal preview, tracking constraint, and reference model choice on tracking performance. Suboptimal l1 control where the closed-loop system has a zero on the unit circle due to integral action in the feedback controller is given special attention, and is seen to give near optimal performance for the system under study here. For the specific trajectory employed here, the best performing feedforward controllers were experimentally seen to reduce by more than half the maximum and rms tracking errors of the H∞ optimal feedback closed-loop systems.

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Output Feedback Controller Design Based on Fuzzy Singularly Perturbed Model

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.466-467.1402 ◽

2012 ◽

Vol 466-467 ◽

pp. 1402-1406 ◽

Cited By ~ 2

Author(s):

Li Li ◽

Fu Chun Sun

Keyword(s):

Closed Loop ◽

Controller Design ◽

Reference Model ◽

Singularly Perturbed ◽

Singularly Perturbed System ◽

Tracking Errors ◽

Perturbed System ◽

Closed Loop Systems ◽

The Stability ◽

Perturbed Model

We will propose a kind of new controller for the nonlinear singularly perturbed system with immeasurable states on the basis of the Fuzzy Singularly Perturbed Model (FSPM). An observer is designed to approximate the immeasurable tracking errors. Two-step approach and Schur theory are used to solve Bilinear Matrix Inequation(BMI) to achieve the gains of the controller and the observer. It can make the states of the plant to follow those of the stable reference model. Lyapunov constitute techniques can be used to prove the stability of the closed-loop systems. Finally the simulation is offered to illustrate the effectiveness of the proposed approach.

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Control of Linear Motors for Machine Tool Feed Drives: Design and Implementation of H∞ Optimal Feedback Control

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.2802339 ◽

1996 ◽

Vol 118 (4) ◽

pp. 649-656 ◽

Cited By ~ 91

Author(s):

D. M. Alter ◽

Tsu-Chin Tsao

Keyword(s):

Machine Tool ◽

Closed Loop ◽

Force Feedback ◽

Dynamic Stiffness ◽

Tracking Performance ◽

Optimal Feedback Control ◽

Optimal Position ◽

Linear Motors ◽

Feed Drives ◽

Position Feedback

Direct drive linear motors have good potential for use as next generation machine tool feed drives since they can increase machining rates and improve servo accuracy by eliminating gear related mechanical problems. To exploit the high speed and high response direct drives for machining, the servo control must achieve as high as possible tracking performance while at the same time establishing as much as possible the dynamic stiffness in order to maintain machining stability and reduce the effect of machining disturbance forces on the tool position. This paper investigates the use of optimal H∞ control to design for large stiffness and closed-loop tracking performance. Position feedback alone is first considered, with cutting force feedback later added to augment closed loop stiffness. Optimal position feedback is experimentally seen to achieve up to a 46 percent stiffness improvement over that achievable with proportional-derivative control. The addition of force feedback to the servo-loop resulted in a further 70 to 100 percent stiffness improvement over the position feedback alone values.

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Linear Model-based Feedforward Control for Improving Tracking-performance of Linear Motors

Asian Journal of Control ◽

10.1002/asjc.842 ◽

2014 ◽

Vol 16 (6) ◽

pp. 1602-1611 ◽

Cited By ~ 2

Author(s):

Yan-Jang Li ◽

Szu-Chi Tien

Keyword(s):

Linear Model ◽

Feedforward Control ◽

Tracking Performance ◽

Linear Motors ◽

Model Based

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Force ripple compensation of the directly-driven linear motors via iterative tuning feed-forward controller

Proceedings of the Institution of Mechanical Engineers Part I Journal of Systems and Control Engineering ◽

10.1177/0959651819827707 ◽

2019 ◽

Vol 233 (9) ◽

pp. 1239-1247

Author(s):

Jianhua Wu ◽

Chao Liu ◽

YongJiang Liu ◽

Zhenhua Xiong ◽

Han Ding

Keyword(s):

High Performance ◽

Tracking Performance ◽

Harmonic Model ◽

Tracking Errors ◽

Flexible Coupling ◽

Feed Forward ◽

Tuning Method ◽

Linear Motors ◽

Force Ripple ◽

Feed Forward Controller

Linear motors are promising in improving the manufacturing equipments’ performance because of eliminating the flexible coupling component. However, the force ripple produced by the linear motors directly causes the feed fluctuation and thus degrades the motion precision. This article utilizes a feed-forward controller added to the feedback one to compensate its effect for the sake of simplicity and robustness. Considering that the force ripple is periodic to the position, a position-dependent multi-order harmonic model is built and used as the feed-forward controller. In order to obtain the controller parameters for various applications, an iterative tuning method is proposed. This method has the advantage that both the high performance for different trajectories tracking and the robustness to disturbances are guaranteed. Experiments on a linear motor illustrate that the parameters converge rapidly. The results show that the tracking performance is improved greatly and the tracking errors are reduced by 60% at least.

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Realization of Prefilter for Virtual Reference Feedback Tuning Using Closed-Loop Step Response Data

Journal of Robotics and Mechatronics ◽

10.20965/jrm.2016.p0707 ◽

2016 ◽

Vol 28 (5) ◽

pp. 707-714 ◽

Cited By ~ 5

Author(s):

Yoshihiro Matsui ◽

◽

Hideki Ayano ◽

Shiro Masuda ◽

Kazushi Nakano ◽

...

Keyword(s):

Closed Loop ◽

Least Squares Method ◽

Reference Model ◽

Step Response ◽

Model Matching ◽

Matching Problem ◽

Virtual Reference ◽

Response Data ◽

Closed Loop Systems ◽

The Time Domain

[abstFig src='/00280005/13.jpg' width='300' text='VRFT model matching problem with prefilter F(z)' ] Prefilters for Virtual Reference Feedback Tuning (VRFT) in the time domain are realized by the least-squares method with step reference response data acquired from the closed-loop system to be tuned and are used to obtain controller parameters for making closed-loop systems as close as possible to the desired reference model. The usefulness of this proposal is shown in numerical examples in which fifth-order and PID controllers for a flexible transmission system are tuned by VRFT with prefilters.

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Observer-Based Mixedℋ2/ℋ∞Tracking Control for Continuous-Time Systems with Integral Action and Pole Placement

Discrete Dynamics in Nature and Society ◽

10.1155/2012/840986 ◽

2012 ◽

Vol 2012 ◽

pp. 1-13

Author(s):

Huxiong Li

Keyword(s):

Continuous Time ◽

Tracking Control ◽

Closed Loop ◽

State Feedback Control ◽

Pole Placement ◽

Linear Matrix ◽

Closed Loop Systems ◽

Integral Action ◽

Continuous Time Systems ◽

Time Systems

The tracking problem for continuous-time systems is investigated. It is assumed that the states of the systems are not available. An observer is firstly designed to estimate the states by using theℋ∞method. The control action is consist of a state-feedback control, an integral component, and a feedforward loop. The linear-matrix-inequality region is used to constrain the eigenvalue location for the closed-loop systems. The control gains can be obtained by solving a sequence of linear matrix inequalities (LMIs) which can guarantee the mixedℋ2/ℋ∞performance for the closed-loop systems.

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Base Algorithms of the Direct Adaptive Position-Path Control for Mobile Objects Positioning

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.763.110 ◽

2015 ◽

Vol 763 ◽

pp. 110-119 ◽

Cited By ~ 1

Author(s):

Viacheslav Pshikhopov ◽

Mikhail Medvedev ◽

Victor Krukhmalev ◽

Victor Shevchenko

Keyword(s):

Closed Loop ◽

Control Method ◽

Reference Model ◽

Block Diagram ◽

Dimensional Space ◽

Three Dimensional ◽

Mobile Object ◽

Mobile Objects ◽

Closed Loop Systems ◽

Path Control

Problem of a mobile object positioning in the presence of determinate disturbances is considered in this paper. A mobile object is described by kinematics and dynamics equations of a solid body in three dimensional space. The control inputs of the mobile object are forces and torques. Design of adaptive control is based on position-path control method for mobile objects. In this article two algorithms of the adaptive position-path control are developed. The first algorithm is adaptive position-path control with integration component and a reference model. The second algorithm is adaptive position-path control with a reference model and an extended mobile robot model. Block diagram of the direct adaptive position-path control system with a reference model is suggested. Design procedures of the adaptive position-path control systems and stability analysis of the closed-loop systems are presented. Computer simulation results of the designed adaptive closed-loop systems with both constant and variable disturbances are presented. On base of the analysis and modeling results conclusions are provided.

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Advancing Motivation Feedforward Control of Permanent Magnetic Linear Oscillating Synchronous Motor for High Tracking Precision

Actuators ◽

10.3390/act10060128 ◽

2021 ◽

Vol 10 (6) ◽

pp. 128

Author(s):

Zongxia Jiao ◽

Yuan Cao ◽

Liang Yan ◽

Xinglu Li ◽

Lu Zhang ◽

...

Keyword(s):

High Frequency ◽

Feedforward Control ◽

High Reliability ◽

Synchronous Motor ◽

Tracking Performance ◽

Pi Control ◽

Phase Lag ◽

Linear Motors ◽

Industrial Manufacture ◽

High Control

Linear motors have promising application to industrial manufacture because of their direct motion and thrust output. A permanent magnetic linear oscillating synchronous motor (PMLOSM) provides reciprocating motion which can drive a piston pump directly having advantages of high frequency, high reliability, and easy commercial manufacture. Hence, researching the tracking performance of PMLOSM is of great importance to realizing its popularization and application. Traditional PI control cannot fulfill the requirement of high tracking precision, and PMLOSM performance has high phase lag because of high control stiffness. In this paper, an advancing motivation feedforward control (AMFC), which is a combination of advancing motivation signal and PI control signal, is proposed to obtain high tracking precision of PMLOSM. The PMLOSM inserted with AMFC can provide accurate trajectory tracking at a high frequency. Compared with single PI control, AMFC can reduce the phase lag from −18 to −2.7 degrees, which shows great promotion of the tracking precision of PMLOSM. In addition, AMFC will promote the application of PMLOSM to other working conditions needing high frequency reciprocating tracking performance and give PMLOSM greater future prospects.

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