Multiple model adaptive control with safe switching

Abstract

The purpose of this paper is to marry the two concepts of multiple model adaptive control and safe adaptive control. In its simplest form, multiple model adaptive control involves a supervisor switching among one of a "nite number of controllers as more is learnt about the plant, until one of the controllers is "nally selected and remains unchanged. Safe adaptive control is concerned with ensuring that when the controller is changed in an adaptive control algorithm, the frozen plant}controller combination is never (closed-loop) unstable. This is a non-trivial task since by de"nition of an adaptive control problem, the plant is not fully known. The proposed solution method involves a frequency-dependent performance measure and employs the Vinnicombe metric. The resulting safe switching guarantees depend on the extent to which a closed-loop transfer function can be accurately identi"ed.

Issues on Robust Adaptive Feedback Control

“…In one of the multiple-model approaches, the identification of the most likely model is carried out by a "supervisor" which switches different controllers, based primarily on deterministic concepts (Morse, 1996(Morse, , 1997(Morse, , 1998(Morse, , 2004Narendra and Balakrishnan, 1997;Anderson et al, 2000Anderson et al, , 2001Hespanha et al, 2001). These proofs and results were presented for the case of SISO systems.…”

“…During the past decade a different, more deterministic, approach to adaptive control using multiple models has been initiated (Morse, 1996(Morse, , 1997(Morse, , 1998(Morse, , 2004Anderson et al, 2000Anderson et al, , 2001Hespanha et al, 2001) and research along these lines is still in progress. The methodology is called Supervisory Switching Multiple-Model Adaptive Control (SMMAC).…”

Optimal model distributions in supervisory adaptive control

“…Therefore, an existing open problem in the domain of multi-model adaptive control is the lack of insight regarding the placement locations of model/controller pairs within a given uncertainty set [8]. The best possible placement locations should be sought so that such performance is optimal with respect to a certain criterion.…”

Transient performance, estimator resetting and filtering in nonlinear multiple model adaptive backstepping control

“…To cope with this problem, multiple model adaptive control (MMAC) approaches have been proposed originally for linear systems [1], [2], [3], [4], [5], and [6]. Recently, MMAC ideas have been extended to nonlinear systems in [7], [8], [9], [10], [11] and [12].…”