Adaptive observer for state variables of a time-varying nonlinear system with unknown constant parameters and delayed measurements
https://doi.org/10.17586/2226-1494-2023-23-4-850-853
Abstract
Unknown constant parameters estimation problem for a nonlinear time-varying system with delayed measurements is considered. The objective of this work is to design an adaptive observer for a nonlinear time-varying system. The observer must provide asymptotic convergence of the unknown constant parameters estimates to their true values. The main idea behind the method is to perform the parametrization of initial dynamical system based on GPEBO (Generalized Parameter Estimation Based Observer) technology and to build a linear regression model. The identifcation of linear regression model unknown parameters is performed using least square method with forgetting factor. This work develops the previously published approach for the case of nonlinear time-varying systems with delayed measurements. New parameters estimation algorithm can be applied for technical tasks, such as technical condition control and automatic control systems design.
About the Authors
A. A. BobtsovRussian Federation
Alexey A. Bobtsov — D.Sc., Professor, Director of School of Computer Technologies and Control
sc 8046819200
Saint Petersburg, 197101
N. A. Nikolaev
Russian Federation
Nikolay A. Nikolaev — PhD, Associate Professor, Associate Professor
sc 13105019100
Saint Petersburg, 197101
O. A. Kozachek
Russian Federation
Olga A. Kozachek — Engineer
sc 57219308287
Saint Petersburg, 197101
O. V. Oskina
Russian Federation
Olga V. Oskina — Student, Engineer
sc 57353555800
Saint Petersburg, 197101
References
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Review
For citations:
Bobtsov A.A., Nikolaev N.A., Kozachek O.A., Oskina O.V. Adaptive observer for state variables of a time-varying nonlinear system with unknown constant parameters and delayed measurements. Scientific and Technical Journal of Information Technologies, Mechanics and Optics. 2023;23(4):850-853. (In Russ.) https://doi.org/10.17586/2226-1494-2023-23-4-850-853