Multi-Point Contact Models for Dynamic Self-Righting of a Hexapod Robot

Uluc Saranli, Alfred Rizzi, and Daniel E. Koditschek
Proceedings of the Sixth International Workshop on the Algorithmic Foundations of Robotics (WAFR '04), July, 2004, pp. 75-90.


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Abstract
In this paper, we report on the design of a model-based controller that can achieve dynamical self-righting of a hexapod robot. Extending on our earlier work in this domain, we introduce a tractable multi-point contact model with Coulomb friction. We contrast the singularities inherent to the new model with other available methods and show that for our specific application, it yields dynamics which are well-defined. We then present a feedback controller that achieves "maximal" performance under morphological and actuation constraints, while ensuring the validity of the model by staying away from singularities. Finally, through systematic experiments, we demonstrate that our controller is capable of robust flipping behavior.

Keywords
legged robot, model-based control, contact modeling, flipping, RHex

Notes
Sponsor: DARPA/SPAWAR
Grant ID: N66001-00-C-8026
Associated Lab(s) / Group(s): Microdynamic Systems Laboratory
Associated Project(s): RHex Robot
Number of pages: 16

Text Reference
Uluc Saranli, Alfred Rizzi, and Daniel E. Koditschek, "Multi-Point Contact Models for Dynamic Self-Righting of a Hexapod Robot," Proceedings of the Sixth International Workshop on the Algorithmic Foundations of Robotics (WAFR '04), July, 2004, pp. 75-90.

BibTeX Reference
@inproceedings{Saranli_2004_4837,
   author = "Uluc Saranli and Alfred Rizzi and Daniel E. Koditschek",
   title = "Multi-Point Contact Models for Dynamic Self-Righting of a Hexapod Robot",
   booktitle = "Proceedings of the Sixth International Workshop on the Algorithmic Foundations of Robotics (WAFR '04)",
   pages = "75-90",
   month = "July",
   year = "2004",
}