A tunable mixed feedback oscillator

Weiming Che; Fulvio Forni

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arXiv · 2011.08564

A tunable mixed feedback oscillator

Weiming Che·Fulvio Forni

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Abstract

The interplay of positive and negative feedback loops on different time scales appears to be a fundamental mechanisms for robust and tunable oscillations in both biological systems and electro-mechanical systems. We develop a detailed analysis of a basic three dimensional Lure model to show how controlled oscillations arise from the tuning of positive and negative feedback strengths. Our analysis is based on dominance theory and confirms, from a system-theoretic perspective, that the mixed feedback is a fundamental enabler of robust oscillations. Our results are not limited to three dimensional systems and extend to larger systems via passivity theory, and to uncertain systems via small gain arguments.

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Weiming Che, Fulvio Forni. 2020-11-17. A tunable mixed feedback oscillator. https://arxiv.org/abs/2011.08564

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