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A bipedal walking robot that can fly, slackline, and skateboard

Kim, Kyunam and Spieler, Patrick and Lupu, Elena Sorina and Ramezani, Alireza and Chung, Soon-Jo (2021) A bipedal walking robot that can fly, slackline, and skateboard. Science Robotics, 6 (59). Art. No. eabf8136. ISSN 2470-9476. doi:10.1126/scirobotics.abf8136.

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Numerous mobile robots in various forms specialize in either ground or aerial locomotion, whereas very few robots can perform complex locomotion tasks beyond simple walking and flying. We present the design and control of a multimodal locomotion robotic platform called LEONARDO, which bridges the gap between two different locomotion regimes of flying and walking using synchronized control of distributed electric thrusters and a pair of multijoint legs. By combining two distinct locomotion mechanisms, LEONARDO achieves complex maneuvers that require delicate balancing, such as walking on a slackline and skateboarding, which are challenging for existing bipedal robots. LEONARDO also demonstrates agile walking motions, interlaced with flying maneuvers to overcome obstacles using synchronized control of propellers and leg joints. The mechanical design and synchronized control strategy achieve a unique multimodal locomotion capability that could potentially enable robotic missions and operations that would be difficult for single-modal locomotion robots.

Item Type:Article
Related URLs:
URLURL TypeDescription
Kim, Kyunam0000-0002-7803-1582
Lupu, Elena Sorina0000-0002-3968-2630
Ramezani, Alireza0000-0002-3391-5288
Chung, Soon-Jo0000-0002-6657-3907
Additional Information:© 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Submitted 16 December 2020; Accepted 8 September 2021; Published 6 October 2021. We thank Y. Veys, S. van Nieuwstadt, and B. Cruz for contributing to an early phase of design and control work, as well as N. Esparza-Duran for heel manufacturing. This work was in part funded by the Caltech Gary Clinard Innovation Fund. We thank M. Gharib and the Center for Autonomous Systems and Technologies for the funding support. Author contributions: A.R. and S.-J.C. conceived and envisioned a first prototype of LEO, which was developed by A.R. with critical feedback and input from S.-J.C. S.-J.C. directed the research activities that enabled demonstration of the new LEO robot concept reported in the article. K.K. and P.S. designed the robot, and P.S. selected the main components, built the robot hardware, and implemented the software. K.K., P.S., and E.-S.L. contributed to modeling, controller design and stability proof, and performance analysis of LEO with critical feedback and input from S.-J.C. K.K., P.S., E.-S.L., and S.-J.C. designed experiment plans. P.S. and E.-S.L. performed experiments, and K.K., P.S., and E.-S.L. evaluated experimental results. K.K., P.S., E.-S.L., and S.-J.C. prepared and edited the manuscript, and all authors reviewed the manuscript. Competing interests: California Institute of Technology filed a U.S. nonprovisional patent application on this work on 23 December 2020. Data and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper or the Supplementary Materials.
Group:Center for Autonomous Systems and Technologies (CAST), GALCIT
Funding AgencyGrant Number
Caltech Gary Clinard Innovation FundUNSPECIFIED
Center for Autonomous Systems and TechnologiesUNSPECIFIED
Issue or Number:59
Record Number:CaltechAUTHORS:20211007-153559085
Persistent URL:
Official Citation:K. Kim, P. Spieler, E.-S. Lupu, A. Ramezani, S.-J. Chung, A bipedal walking robot that can fly, slackline, and skateboard. Sci. Robot. 6, eabf8136 (2021); DOI: 10.1126/scirobotics.abf8136
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:111265
Deposited By: Tony Diaz
Deposited On:07 Oct 2021 15:51
Last Modified:21 Oct 2021 16:08

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