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arXiv · 1707.00661

Control Synthesis for an Underactuated Cable Suspended System Using Dynamic Decoupling

Siddharth H. Nair·Ravi N. Banavar·D. H. S. Maithripala
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Abstract

This article studies the dynamics and control of a novel underactuated system, wherein a plate suspended by cables and with a freely moving mass on top, whose other ends are attached to three quadrotors, is sought to be horizontally stabilized at a certain height, with the ball positioned at the center of mass of the plate. The freely moving mass introduces a 2-degree of underactuation into the system. The design proceeds through a decoupling of the quadrotors and the plate dynamics. Through a partial feedback linearization approach, the attitude of the plate and the translational height of the plate is initially controlled, while maintaining a bounded velocity along the $y$ and $x$ directions. These inputs are then synthesized through the quadrotors with a backstepping and timescale separation argument based on Tikhonov's theorem.

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Siddharth H. Nair, Ravi N. Banavar, D. H. S. Maithripala. 2017-07-03. Control Synthesis for an Underactuated Cable Suspended System Using Dynamic Decoupling. https://arxiv.org/abs/1707.00661

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