Multiple model adaptive control. part 2: switching. International journal of robust and nonlinear control (0)

by J P Hespanha, D Liberzon, A S Morse, B D O Anderson, T S Brinsmead, F De Bruyne
Results 1 - 10 of 35

Stability of switched systems with average dwell-time

by João P. Hespanha - In Proc. 38th IEEE Conf. on Decision and Control , 1999
"... It is shown that switching among stable linear systems results in a stable system provided that switching is “slow-on-the-average. ” In particular, it is proved that exponential stability is achieved when the number of switches in any finite interval grows linearly with the length of the interval, a ..."
Abstract - Cited by 219 (26 self) - Add to MetaCart
It is shown that switching among stable linear systems results in a stable system provided that switching is “slow-on-the-average. ” In particular, it is proved that exponential stability is achieved when the number of switches in any finite interval grows linearly with the length of the interval, and the growth rate is sufficiently small. Moreover, the exponential stability is uniform over all switchings with the above property. For switched systems with inputs this guarantees that several input-to-state induced norms are bounded uniformly over all slow-on-the-average switchings. These results extend to classes of nonlinear switched systems that satisfy suitable uniformity assumptions. In this paper it is also shown that, in a supervisory control context, scale-independent hysteresis can produce switching that is slow-on-the-average and therefore the results mentioned above can be used to study the stability of hysteresis-based adaptive control systems. 1

Switching between stabilizing controllers

by João P. Hespanha , A. Stephen Morse
"... www.elsevier.com/locate/automatica ..."
Abstract - Cited by 44 (3 self) - Add to MetaCart
www.elsevier.com/locate/automatica

Overcoming the Limitations of Adaptive Control By Means of Logic-Based Switching

by Joao P. Hespanha, Daniel Liberzon, A. Stephen Morse , 2002
"... In this paper we describe a framework for deterministic adaptive control which involves logic-based switching among a family of candidate controllers. We compare it with more conventional adaptive control techniques that rely on continuous tuning, emphasizing how switching and logic can be used to o ..."
Abstract - Cited by 34 (8 self) - Add to MetaCart
In this paper we describe a framework for deterministic adaptive control which involves logic-based switching among a family of candidate controllers. We compare it with more conventional adaptive control techniques that rely on continuous tuning, emphasizing how switching and logic can be used to overcome some of the limitations of traditional adaptive control. The issues are discussed in a tutorial, non-technical manner and illustrated with specific examples.

Issues on robust adaptive feedback control

by Michael Athans, Sajjad Fekri, Antonio Pascoal - In: Preprints of the 16th IFAC World Congress. Prague, Czech Rep , 2005
"... Abstract: We discuss recent progress in the field of robust adaptive control with special emphasis on methodologies that use multiple-model architectures. We emphasize that the selection of the number of models, estimators and compensators in such architectures must be based on precise definition of ..."
Abstract - Cited by 16 (4 self) - Add to MetaCart
Abstract: We discuss recent progress in the field of robust adaptive control with special emphasis on methodologies that use multiple-model architectures. We emphasize that the selection of the number of models, estimators and compensators in such architectures must be based on precise definition of the robust performance requirements. We illustrate some of the concepts and outstanding issues for a new methodology that blends robust nonadaptive mixed µ-synthesis and stochastic hypothesis-testing concepts leading to the so-called RMMAC architecture. A numerical example is used to illustrate the RMMAC design methodology. Copyright c © 2005 IFAC

Liberzon D. ISS of switched systems and applications to switching adaptive control

by L. Vu, D. Chatterjee, D. Liberzon - IEEE Int. Conf. on Decision and Control , 2005
"... Abstract — In this paper we prove that a switched nonlinear system has several useful ISS-type properties under average dwell-time switching signals if each constituent dynamical system is ISS. This extends available results for switched linear systems. We apply our result to stabilization of uncert ..."
Abstract - Cited by 11 (0 self) - Add to MetaCart
Abstract — In this paper we prove that a switched nonlinear system has several useful ISS-type properties under average dwell-time switching signals if each constituent dynamical system is ISS. This extends available results for switched linear systems. We apply our result to stabilization of uncertain nonlinear systems via switching supervisory control, and show that the plant states can be kept bounded in the presence of bounded disturbances when the candidate controllers provide ISS properties with respect to the estimation errors. Detailed illustrative examples are included. I.

The Power Dissipation Method and Kinematic Reducibility of Multiple Model Robotic Systems

by T. D. Murphey , J. W. Burdick - ACCEPTED FOR PUBLICATION IN IEEE TRANSACTIONS ON ROBOTICS
"... This paper develops a formal connection between ..."
Abstract - Cited by 6 (5 self) - Add to MetaCart
This paper develops a formal connection between

Multiple-model adaptive estimation of a hydraulic wind power system

by Masoud Vaezi, Afshin Izadian, Senior Member - in Proc. 39th Annu. Conf. IEEE Ind. Electron. Soc. (IECON , 2013
"... Abstract—Nonlinear model of hydraulic wind power system operates on a wide spectrum of operating points such as random wind speed disturbances and applied control commands. Thus, one way to linearize this model is to use multiple linear models representing the whole range of operating points. This p ..."
Abstract - Cited by 6 (6 self) - Add to MetaCart
Abstract—Nonlinear model of hydraulic wind power system operates on a wide spectrum of operating points such as random wind speed disturbances and applied control commands. Thus, one way to linearize this model is to use multiple linear models representing the whole range of operating points. This paper introduces a minimal number of fixed linear models in a multiple model adaptive estimation (MMAE) framework to reduce the state estimation error. System parameters such as pressures of the pump and motors can be estimated while the overall error in entire operating points is reduced. The algorithm is composed of a bank of Kalman filters, each of which is modeled to match particular real world operating condition. Simulation results demonstrate that the adaptive approach can optimally estimate the state variables in a wide range of operating points. I.
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Multiple-Model Adaptive Control With Set-Valued Observers

by Paulo Rosa, Carlos Silvestre, Jeff S. Shamma, Michael Athans , 909
"... Abstract — This paper proposes a multiple-model adaptive control methodology, using set-valued observers (MMAC-SVO) for the identification subsystem, that is able to provide robust stability and performance guarantees for the closed-loop, when the plant, which can be open-loop stable or unstable, ha ..."
Abstract - Cited by 5 (4 self) - Add to MetaCart
Abstract — This paper proposes a multiple-model adaptive control methodology, using set-valued observers (MMAC-SVO) for the identification subsystem, that is able to provide robust stability and performance guarantees for the closed-loop, when the plant, which can be open-loop stable or unstable, has significant parametric uncertainty. We illustrate, with an example, how set-valued observers (SVOs) can be used to select regions of uncertainty for the parameters of the plant. We also discuss some of the most problematic computational shortcomings and numerical issues that arise from the use of this kind of robust estimation methods. The behavior of the proposed control algorithm is demonstrated in simulation. I.
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Tutorial on supervisory control

by João P. Hespanha , 2001
"... This paper provides an overview of the results available on supervisory control in an adaptive context, with special emphasis on estimator-based supervisory architectures. We cover both the linear and nonlinear cases in a unified manner, highlighting the common properties and analysis techniques. Th ..."
Abstract - Cited by 3 (0 self) - Add to MetaCart
This paper provides an overview of the results available on supervisory control in an adaptive context, with special emphasis on estimator-based supervisory architectures. We cover both the linear and nonlinear cases in a unified manner, highlighting the common properties and analysis techniques. The style of the paper is tutorial and provides the reader with enough detail to apply these techniques to general classes of linear and nonlinear systems. Contents
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Stability overlay for adaptive control laws applied to linear time-invariant systems (accepted

by Paulo Rosa, Jeff S. Shamma, Carlos Silvestre, Michael Athans - In Proceedings of the 2009 American Control Conference , 2009
"... Abstract — Two broad classes of adaptive control algorithms can be found in the literature: i) stability based, with minimal assumptions on the plant; ii) performance based, with relatively more stringent assumptions on the plant. This paper proposes a solution, referred to as Stability Overlay (SO) ..."
Abstract - Cited by 3 (3 self) - Add to MetaCart
Abstract — Two broad classes of adaptive control algorithms can be found in the literature: i) stability based, with minimal assumptions on the plant; ii) performance based, with relatively more stringent assumptions on the plant. This paper proposes a solution, referred to as Stability Overlay (SO), to enable stability guarantees in performance based algorithms. In our methodology, the performance based adaptive control laws are only responsible for designating the controller that should be selected; the SO decides whether this controller should or not be used, based upon its most recent history of utilization. We argue that using two algorithms in parallel – the SO for stability purposes and any other suitable for the performance requirements – leads to higher levels of performance while guaranteeing stability of the adaptive closed-loop for bounded (but unknown) disturbances. The SO methodology is applicable to both time-invariant and time-varying, nonlinear and linear systems. However, due to space limitations, we only consider linear time-invariant (LTI) plants in this paper. The theory is illustrated with an example. I.
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