Almost-global tracking of the unactuated joint in a pendubot

Aradhana Nayak; Ravi N. Banavar

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arXiv · 1710.10379

Almost-global tracking of the unactuated joint in a pendubot

Aradhana Nayak·Ravi N. Banavar

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Abstract

Tracking the unactuated configuration variable in an underactuated system, in a global sense, has not received much attention. Here we present a scheme to do so for a pendubot - a two link robot actuated only at the first link. We propose a control law for almost-global asymptotic tracking (AGAT) of a smooth reference trajectory for the unactuated second joint of the pendubot. The control law achieves almost-global tracking for any smooth reference trajectory specified for the unactuated joint. Further, we generalize the proposed scheme to an n-link system with as many (or more) degrees of actuation than unactuation, and show that the result holds.

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Aradhana Nayak, Ravi N. Banavar. 2017-10-28. Almost-global tracking of the unactuated joint in a pendubot. https://arxiv.org/abs/1710.10379

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