Departmental Papers (ESE)


We report on the design and analysis of a controller that can achieve dynamical self-righting of our hexapedal robot, RHex. Motivated by the initial success of an empirically tuned controller, we present a feedback controller based on a saggital plane model of the robot. We also extend this controller to develop a hybrid pumping strategy that overcomes actuator torque limitations, resulting in robust flipping behavior over a wide range of surfaces. We present simulations and experiments to validate the model and characterize the performance of the new controller.

Document Type

Journal Article

Subject Area

GRASP, Kodlab

Date of this Version

September 2004


Reprinted from The International Journal of Robotics Research, Volume 23, Issue 9, September 2004, pages 903-918.
DOI: 10.1177/0278364904045594

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


legged robot, model-based control, contact modeling, dynamic manipulation, experimentation



Date Posted: 30 June 2008

This document has been peer reviewed.