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ORDER EXTENSION OF NONLINEAR SYSTEMS FOR OBSERVER DESIGN UNDER REDUCED OBSERVABILITY PROPERTIES
Alejandro Vargas*, Jaime Moreno* and Michael Zeitz**
* Instituto de Ingeniería, UNAM, Ap. Postal 70-472,
México D.F., 04510 Mexico
e-mail: moreno@pumas.iingen.unam.mx
** Institut für Systemdynamik und Regelungstechnik (ISR),
Universität Stuttgart, PB 801140, D-70511 Stuttgart/Germany
e-mail: {vargas, zeitz}@isr.uni-stuttgart.de
Nonlinear unforced systems of order n with reduced observability properties are considered, such that their r-observability map is injective only for r > n. An immersion into a higher order system containing the original system coordinates is proposed, such that estimation of the original states of the system is simplified. Approximate or event-based observers are proposed when some properties are lost for the extension. Observer design is illustrated by examples and a simplified aerobic bioreactor model.
Keywords: observers, observability, nonlinear systems, singular points, immersion
Session slot T-Fr-M08: Nonlinear observers/Area code 2c : Non-linear Systems
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