Drosophila uses a tripod gait across all walking speeds, and the geometry of the tripod is important for speed control
Changes in walking speed are characterized by changes in both the animal's gait and the mechanics of its interaction with the ground. Here we study these changes in walking Drosophila. We measured the fly's center of mass (CoM) movement with high spatial resolution and the position of its footprints. Flies predominantly employ a modified tripod gait that only changes marginally with speed. The mechanics of a tripod gait can be approximated with a simple model – angular and radial spring-loaded inverted pendulum (ARSLIP) – which is characterized by two springs of an effective leg that become stiffer as the speed increases. Surprisingly, the change in the stiffness of the spring is mediated by the change in tripod shape rather than a change in stiffness of the individual leg. The effect of tripod shape on mechanics can also explain the large variation in kinematics among insects, and ARSLIP can model these variations.
Data is available on Dryad under doi:10.5061/dryad.m63xsj41g and Github https://github.com/vbhandawat/FlyTripod_eLife_2021/
Data from: Drosophila uses a tripod gait across all walking speeds, and the geometry of the tripod is important for speed controlDryad Digital Repository, 10.5061/dryad.m63xsj41g.
Article and author information
National Science Foundation (IOS-1652647)
- Vikas Bhandawat
National Institute on Deafness and Other Communication Disorders (RO1DC015827)
- Vikas Bhandawat
National Institute of Neurological Disorders and Stroke (RO1NS097881)
- Vikas Bhandawat
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Gordon J Berman, Emory University, United States
- Received: December 17, 2020
- Accepted: January 22, 2021
- Accepted Manuscript published: February 3, 2021 (version 1)
- Version of Record published: March 4, 2021 (version 2)
© 2021, Chun et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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