Departmental Papers (ESE)


We report on the design and analysis of a controller which can achieve dynamical self-righting of our hexapedal robot, RHex. We present an empirically developed control procedure which works reasonably well on indoor surfaces, using a hybrid energy pumping strategy to overcome torque limitations of its actuators. Subsequent modeling and analysis yields a new controller with a much wider domain of success as well as a preliminary understanding of the necessary hybrid control strategy. Simulation results demonstrate the superiority of the improved control strategy to the first generation empirically designed controller.

Document Type

Conference Paper

Subject Area

GRASP, Kodlab

Date of this Version

May 2002


Copyright 2003 IEEE. Reprinted from Proceedings of the IEEE International Conference on Robotics and Automation, Volume 3, 2003, pages 2209-2215.

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NOTE: At the time of publication, author Daniel Koditschek was affiliated with the University of Michigan. Currently, he is a faculty member in the Department of Electrical and Systems Engineering at the University of Pennsylvania.



Date Posted: 02 June 2008

This document has been peer reviewed.