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arXiv · 2309.16830

Robust Safe Control with Multi-Modal Uncertainty

Tianhao Wei·Liqian Ma·Ravi Pandya·Changliu Liu
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Abstract

Safety in dynamic systems with prevalent uncertainties is crucial. Current robust safe controllers, designed primarily for uni-modal uncertainties, may be either overly conservative or unsafe when handling multi-modal uncertainties. To address the problem, we introduce a novel framework for robust safe control, tailored to accommodate multi-modal Gaussian dynamics uncertainties and control limits. We first present an innovative method for deriving the least conservative robust safe control under additive multi-modal uncertainties. Next, we propose a strategy to identify a locally least-conservative robust safe control under multiplicative uncertainties. Following these, we introduce a unique safety index synthesis method. This provides the foundation for a robust safe controller that ensures a high probability of realizability under control limits and multi-modal uncertainties. Experiments on a simulated Segway validate our approach, showing consistent realizability and less conservatism than controllers designed using uni-modal uncertainty methods. The framework offers significant potential for enhancing safety and performance in robotic applications.

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Tianhao Wei, Liqian Ma, Ravi Pandya, Changliu Liu. 2023-09-28. Robust Safe Control with Multi-Modal Uncertainty. https://arxiv.org/abs/2309.16830

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