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arXiv · 1603.06627

Safety Verification of Output Feedback Controllers for Nonlinear Systems

Abstract

A high-gain observer is used for a class of feedback linearisable nonlinear systems to synthesize safety-preserving controllers over the observer output. A bound on the distance between trajectories under state and output feedback is derived, and shown to converge to zero as a function of the gain parameter of an observer. We can therefore recover safety properties under output feedback and control saturation constraints by synthesizing a controller as if the full state were available. We specifically design feedback linearising controllers that satisfy certain properties, such as stability, and then construct the associated maximal safety-invariant set, namely the largest set of all initial states that are guaranteed to produce safe trajectories over a given (possibly infinite) time horizon.

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BibTeXRIS

Kendra Lesser, Alessandro Abate. 2016-03-21. Safety Verification of Output Feedback Controllers for Nonlinear Systems. https://arxiv.org/abs/1603.06627

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