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As dynamic robot behaviors become more capable and well understood, the need arises for a wide variety of equally capable and systematically applicable transitions between them. We use a hybrid systems framework to characterize the dynamic transitions of a planar “legged” rigid body from rest on level ground to a fully aerial state. The various contact conditions fit together to form a topologically regular structure, the “ground reaction complex”. The body’s actuated dynamics excite multifarious transitions between the cells of this complex, whose regular adjacency relations index naturally the resulting “leaps” (path sequences through the cells from rest to free flight). We exhibit on a RHex robot some of the most interesting “words” formed by these achievable path sequences, documenting unprecedented levels of performance and new application possibilities that illustrate the value of understanding and expressing this vocabulary systematically.

For more information: Kod*Lab

Sponsor Acknowledgements

This work was supported by the ARL/GDRS RCTA project under Cooperative Agreement Number W911NF-10–2−0016.

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Conference Paper

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BibTeX entry

@inproceedings{paper:johnson-icra-2013, author = {Aaron M. Johnson and D E Koditschek}, title = {Toward a Vocabulary of Legged Leaping}, booktitle = {Proceedings of the 2013 IEEE Intl. Conference on Robotics and Automation}, month = {May}, year = {2013}, pages = {2553--2560} }

Copyright 2013 IEEE. Reprinted from Proceedings of the 2013 IEEE International Conference on Robotics and Automation .

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Date Posted: 19 February 2014

This document has been peer reviewed.