Departmental Papers (ESE)


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This paper develops a comparative framework for the design of an actuated inertial appendage for planar reorientation. We define the Inertial Reorientation template, the simplest model of this behavior, and leverage its linear dynamics to reveal the design constraints linking a task with the body designs capable of completing it. As practicable inertial appendage designs lead to physical bodies that are generally more complex, we advance a notion of “anchoring” whereby a judicious choice of physical design in concert with an appropriate control policy yields a system whose closed loop dynamics are sufficiently captured by the template as to permit all further design to take place in its far simpler parameter space. This approach is effective and accurate over the diverse design spaces afforded by existing platforms, enabling performance comparison through the shared task space. We analyze examples from the literature and find advantages to each body type, but conclude that tails provide the highest potential performance for reasonable designs. Thus motivated, we build a physical example by retrofitting a tail to a RHex robot and present empirical evidence of its efficacy.

For more information: Kod*lab

Sponsor Acknowledgements

This work was supported in part by the ARL/GDRS RCTA and in part by the NSF under the CiBER-IGERT Award DGE-0903711 and the CABiR Award CDI-II 1028237.

Document Type

Journal Article

Subject Area

GRASP, Kodlab

Date of this Version


Publication Source

IEEE Transactions on Robotics





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Copyright/Permission Statement

© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

Bib Tex

@article{paper:libby_tails_2016, title = {Comparative Design, Scaling, and Control of Appendages for Inertial Reorientation}, author = {Thomas Libby and Aaron M. Johnson and Evan Chang-Siu and Robert J. Full and D. E. Koditschek}, year = {2016}, journal = {IEEE Transactions on Robotics}, volume = {32}, number = {6}, pages = {1380--1398}, _note = {Available as an arXiv Preprint arXiv:1511.05958 [cs.RO]} }



Date Posted: 03 April 2017

This document has been peer reviewed.