Input-delay compensation in a robust adaptive control framework

Kim Doang Nguyen, Harry Dankowicz

Research output: Contribution to journalArticle

Abstract

A modification to the ℒ1 control framework for uncertain systems with actuator delays is presented. Specifically, a time delay is introduced in the control input of the state predictor to compensate for the destabilising effect of an input delay in the plant. For this modified framework, the analysis shows that the output of the adaptive system closely follows the behaviour of a suitably defined, non-adaptive, stable reference system provided that a delay-dependent stability condition is satisfied and the adaptive gain is chosen sufficiently large. The set of combinations of input delay and compensation delay for which the stability condition is satisfied contains an open set of pairs of positive values provided that a filter bandwidth is chosen sufficiently large. The efficacy of the delay compensation is illustrated by a simple example. A numerical continuation is also performed to explore the stability region for a case where this can be approximated a priori.

Original languageEnglish (US)
Pages (from-to)1718-1727
Number of pages10
JournalIET Control Theory and Applications
Volume13
Issue number11
DOIs
StatePublished - Jul 23 2019

Fingerprint

Robust Adaptive Control
Input Delay
Stability Condition
Numerical Continuation
Delay-dependent Stability
Uncertain systems
Stability Region
Adaptive systems
Adaptive Systems
Uncertain Systems
Open set
Efficacy
Actuator
Predictors
Time Delay
Time delay
Actuators
Bandwidth
Filter
Output

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Human-Computer Interaction
  • Computer Science Applications
  • Control and Optimization
  • Electrical and Electronic Engineering

Cite this

Input-delay compensation in a robust adaptive control framework. / Nguyen, Kim Doang; Dankowicz, Harry.

In: IET Control Theory and Applications, Vol. 13, No. 11, 23.07.2019, p. 1718-1727.

Research output: Contribution to journalArticle

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