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arXiv · 2003.01868

Robust Instability Analysis with Application to Neuronal Dynamics

Shinji Hara·Tetsuya Iwasaki·Yutaka Hori
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Abstract

This paper is concerned with robust instability analysis of linear feedback systems subject to a dynamic uncertainty. The work is motivated by, and provides a basic foundation for, a more challenging problem of analyzing persistence of oscillations in nonlinear dynamical systems. We first formalize the problem for SISO LTI systems by introducing a notion of the robust instability radius (RIR). We provide a method for calculating the RIR exactly for a certain class of systems and show that it works well for a class of second order systems. This result is applied to the FitzHugh-Nagumo model for neuronal dynamics, and the effectiveness is confirmed by numerical simulations, where we properly care for the change of the equilibrium point.

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BibTeXRIS

Shinji Hara, Tetsuya Iwasaki, Yutaka Hori. 2020-03-04. Robust Instability Analysis with Application to Neuronal Dynamics. https://doi.org/10.1109/cdc42340.2020.9304320

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