Sampled-data observers with generalized holds for unstable plants

Author

Haddad, Wassim M. ; Huang, Hsing-Hsin ; Bernstein, Dennis S.

Author_Institution

Dept. of Mech. & Aerosp. Eng., Florida Inst. of Technol., Melbourne, FL, USA

Volume

39

Issue

1

fYear

1994

fDate

1/1/1994 12:00:00 AM

Firstpage

229

Lastpage

234

Abstract

Optimality conditions are derived for reduced-order sampled-data estimation satisfying an observation constraint that involves a prespecified, possibly unstable, subspace of the system dynamics. It is shown that a generalized hold device possessing a time-varying exponential intersample profile is essential in order to account for the unstable dynamics. In particular, it is shown that with a continuous-time quadratic performance measure a zero-order-hold device may result in an unbounded (infinite) cost. An additional feature of the problem is the utilization of an averaging A/D device within the continuous-time/discrete-time conversion which results in averaged measurements depending upon delayed samples of the state

Keywords

dynamics; large-scale systems; sampled data systems; state estimation; averaged measurements; averaging A/D device; continuous-time quadratic performance measure; continuous-time/discrete-time conversion; generalized hold device; generalized holds; observation constraint; optimality conditions; reduced-order sampled-data estimation; sampled-data observers; system dynamics; time-varying exponential intersample profile; unbounded infinite cost; unstable dynamics; unstable plants; zero-order-hold device; Aerodynamics; Costs; Delay; Estimation theory; Measurement standards; Particle measurements; Sampling methods; State estimation; Subspace constraints; White noise;

fLanguage

English

Journal_Title

Automatic Control, IEEE Transactions on

Publisher

ieee

ISSN

0018-9286

Type

jour

DOI

10.1109/9.273375

Filename

273375