Volume 23 Issue 9- Publication Date: 1 September 2004
Model-Based Dynamic Self-Righting Maneuvers for a Hexapedal Robot
U. Saranli, A.A. Rizzi, Robotics Institute, Carnegie Mellon University, Pittsburgh, PA 15223, USA and D.E. Koditschek Department of Electrical Engineering and Computer Science, The University of Michigan, Ann Arbor, MI 48109-2110, USA

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.

Multimedia Key
= Video = Data = Code = Image
Example One: RHex 0.5 flipping on linoleum with the original open-loop controller. (1.4MB)
Example Two: RHex 0.5 flipping on carpet with the original open-loop controller. Multiple thrusts are required for a successful flip. (0.9MB)
Example Three: High-speed video (150fps) of RHex 1.5 flipping on linoleum with the model based controller. (1.5MB)
Example Four: Data files and visualization scripts for all the experiments and simulations. Please see README.txt in this archive for details on the format of data files and the usage of associated scripts. (108.9MB in total)
Example Five: RHex 1.5 flipping on carpet with the model-based controller. (1.4MB)
Example Six : RHex 1.5 flipping on packed dirt with the model-based controller. (0.8MB)
Example Seven: RHex 1.5 flipping on asphalt with the model-based controller. (1.1MB)
Example Eight : RHex 1.5 failing to flip on thick grass with the model-based controller. (1.1MB)
Example Nine : RHex 1.5 flipping on thin grass with the model-based controller. (0.9MB)
Return to Contents