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arXiv · 1805.09914

Finite Time Robust Control of the Sit-to-Stand Movement for Powered Lower Limb Orthoses

Octavio Narvaez-Aroche·Andrew Packard·Murat Arcak
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Abstract

This study presents a technique to safely control the Sit-to-Stand movement of powered lower limb orthoses in the presence of parameter uncertainty. The weight matrices used to calculate the finite time horizon linear-quadratic regulator (LQR) gain in the feedback loop are chosen from a pool of candidates as to minimize a robust performance metric involving induced gains that measure the deviation of variables of interest in a linear time-varying (LTV) system, at specific times within a finite horizon, caused by a perturbation signal modeling the variation of the parameters. Two relevant Sit-to-Stand movements are simulated for drawing comparisons with the results documented in a previous work.

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Octavio Narvaez-Aroche, Andrew Packard, Murat Arcak. 2018-05-24. Finite Time Robust Control of the Sit-to-Stand Movement for Powered Lower Limb Orthoses. https://doi.org/10.23919/acc.2018.8431465

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