Departmental Papers (ESE)


Fig. 1. Control of a hopping behavior expressed as a hierarchical composition of closed-loop templates. Notionally, the grey arrows represent directed template-anchor relations. Center: A model of the tailed monoped physical platform on which we implement tail-energized planar hopping, labeled with configuration variables (black), actuators (red), and model parameters (blue)..

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We have built a 4DOF tailed monoped that hops along a boom permitting free sagittal plane motion. This underactuated platform is powered by a hip motor that adjusts leg touchdown angle in flight and balance in stance, along with a tail motor that adjusts body shape in flight and drives energy into the passive leg shank spring during stance. The motor control signals arise from the application in parallel of four simple, completely decoupled 1DOF feedback laws that provably stabilize in isolation four corresponding 1DOF abstract reference plants. Each of these abstract 1DOF closedloopdynamicsrepresentssomesimplebutcrucialspecific component of the locomotion task at hand. We present a partial proof of correctness for this parallel composition of “template” reference systems along with data from the physical platform suggesting these templates are “anchored” as evidenced by the correspondence of their characteristic motions with a suitably transformed image of traces from the physical platform.

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Sponsor Acknowledgements

This work was supported in part by the ARL/GDRS RCTA project, Coop. Agreement #W911NF-1020016 and in part by NSF grant #1028237

Document Type

Conference Paper

Subject Area

GRASP, Kodlab

Date of this Version


Publication Source

2015 IEEE Intl. Conference on Robotics and Automation



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Bib Tex

@inproceedings{de2015parallel, title={Parallel composition of templates for tail-energized planar hopping}, author={De, Avik and Koditschek, Daniel E}, booktitle={Robotics and Automation (ICRA), 2015 IEEE International Conference on}, pages={4562--4569}, year={2015}, organization={IEEE} }



Date Posted: 26 October 2016

This document has been peer reviewed.