PI-type iterative learning control revisited
- 1 January 2002
- conference paper
- conference paper
- Published by Institute of Electrical and Electronics Engineers (IEEE) in Proceedings of the 2002 American Control Conference (IEEE Cat. No.CH37301)
- Vol. 3, 2138-2143 vol.3
- https://doi.org/10.1109/acc.2002.1023953
Abstract
Iterative learning control (ILC) is a value-added block to enhance the feedback control performance by utilizing the fact that the system is operated repeatedly for the same task. In terms of how to use the tracking error signal of previous iteration to form the control signal of current iteration, ILC updating schemes can be classified as P-type, D-type, PI-type and PID type etc. So far, no one answered this question: what's the use of the error integral in ILC updating law? In this paper, for discrete-time linear time invariant systems, we show that the error integral in ILC updating scheme is helpful in achieving a monotonic convergence in a suitable norm topology other than the exponentially weighted sup-norm. Optimal design of PI-type ILC scheme is presented. Two extreme cases are considered to show that PI-type ILC can be better than P-type ILC in terms of convergence speed. Simulation results are presented to illustrate how to optimal design the PI-type ILC. We also show that when the number of time instants in an iteration is large, I-component in ILC updating law is of little use.Keywords
This publication has 14 references indexed in Scilit:
- Exponential convergence of an iterative learning controller for time-varying nonlinear systemsPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2003
- Iterative learning control-Convergence using high gain feedbackPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2003
- On the role of high gain feedback in P-type learning control of robotsPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2002
- Discrete frequency based learning control for precision motion controlPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2002
- An observation about monotonic convergence in discrete-time, P-type iterative learning controlPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2002
- An iterative learning controller with reduced sampling rate for plants with variations of initial statesInternational Journal of Control, 2000
- Iterative Learning Control for Deterministic SystemsPublished by Springer Science and Business Media LLC ,1993
- A discrete-time design of robust iterative learning controllersIEEE Transactions on Systems, Man, and Cybernetics, 1992
- Bettering operation of Robots by learningJournal of Robotic Systems, 1984
- Formation of High-Speed Motion Pattern of a Mechanical Arm by TrialTransactions of the Society of Instrument and Control Engineers, 1978