Volume 21 Issue 05/06 - Publication Date: 1 May 2002
Nonholonomy on Purpose
Rolling Manipulation with a Single Control
Prasun Choudhury and Kevin M. Lynch Laboratory for Intelligent Mechanical Systems Department of Mechanical Engineering Northwestern University Evanston, IL 60208, USA
Underactuated manipulation is the process of controlling several object degrees-of-freedom with fewer robot actuators. Underactuated manipulation allows us to build dexterous robots with only a few actuators. In this paper we explore the possibility of useful dynamic manipulation with only a single actuator. Our case study is a ball rolling in an asymmetrical bowl which can be accelerated along one linear degree-of-freedom. We show that the state of the ball relative to the bowl is controllable by this single controlled acceleration. In particular, it is possible to control the equilibrium orientation of the ball on the three-dimensional manifold SO3 using this single input. We have built an experimental demonstration of this system and we have constructed a motion planner to find a sequence of motions of the bowl to accomplish a desired reorientation.
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