Metastable Walking Machines
Name
Tedrake_Metastable walking.pdf
Size
1.76 MB
Format
Adobe PDF
Checksum (MD5)
19d319b2f6eb018ac2128d0ad0a4f1e5
Author(s)
Byl, Katie
Tedrake, Russell Louis
Date Issued
June 2009
Journal
International journal of robotics research
Publisher
Sage
Citation
Byl, Katie, and Russ Tedrake. “Metastable Walking Machines.” The International Journal Of Robotics Research 28.8 (2009) : 1040 -1064. Copyright © 2009, SAGE Publications
Version
Author's final manuscript
Abstract
Legged robots that operate in the real world are inherently subject to stochasticity in their dynamics and uncertainty about the terrain. Owing to limited energy budgets and limited control authority, these “disturbances” cannot always be canceled out with high-gain feedback. Minimally actuated walking machines subject to stochastic disturbances no longer satisfy strict conditions for limit-cycle stability; however, they can still demonstrate impressively long-living periods of continuous walking. Here, we employ tools from stochastic processes to examine the “stochastic stability” of idealized rimless-wheel and compass-gait walking on randomly generated uneven terrain. Furthermore, we employ tools from numerical stochastic optimal control to design a controller for an actuated compass gait model which maximizes a measure of stochastic stability—the mean first-passage time—and compare its performance with a deterministic counterpart. Our results demonstrate that walking is well characterized as a metastable process, and that the stochastic dynamics of walking should be accounted for during control design in order to improve the stability of our machines.
MIT Department
Massachusetts Institute of Technology. Computer Science and Artificial Intelligence Laboratory
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike 3.0
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1177/0278364909340446
