Machines 2013, 1(1), 33-49; doi:10.3390/machines1010033

Multiple Estimation Architecture in Discrete-Time Adaptive Mixing Control

Received: 11 March 2013; in revised form: 29 April 2013 / Accepted: 20 May 2013 / Published: 29 May 2013
(This article belongs to the Special Issue Advances in Control Engineering)
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract: Adaptive mixing control (AMC) is a recently developed control scheme for uncertain plants, where the control action coming from a bank of precomputed controller is mixed based on the parameter estimates generated by an on-line parameter estimator. Even if the stability of the control scheme, also in the presence of modeling errors and disturbances, has been shown analytically, its transient performance might be sensitive to the initial conditions of the parameter estimator. In particular, for some initial conditions, transient oscillations may not be acceptable in practical applications. In order to account for such a possible phenomenon and to improve the learning capability of the adaptive scheme, in this paper a new mixing architecture is developed, involving the use of parallel parameter estimators, or multi-estimators, each one working on a small subset of the uncertainty set. A supervisory logic, using performance signals based on the past and present estimation error, selects the parameter estimate to determine the mixing of the controllers. The stability and robustness properties of the resulting approach, referred to as multi-estimator adaptive mixing control (Multi-AMC), are analytically established. Besides, extensive simulations demonstrate that the scheme improves the transient performance of the original AMC with a single estimator. The control scheme and the analysis are carried out in a discrete-time framework, for easier implementation of the method in digital control.
Keywords: robust adaptive control; multiple-model mixing control; hysteresis switching logic
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MDPI and ACS Style

Baldi, S. Multiple Estimation Architecture in Discrete-Time Adaptive Mixing Control. Machines 2013, 1, 33-49.

AMA Style

Baldi S. Multiple Estimation Architecture in Discrete-Time Adaptive Mixing Control. Machines. 2013; 1(1):33-49.

Chicago/Turabian Style

Baldi, Simone. 2013. "Multiple Estimation Architecture in Discrete-Time Adaptive Mixing Control." Machines 1, no. 1: 33-49.

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