Snakes are pretty cool. And the coolest thing is that snakes not only can move around, they are really good at moving around. In 3D! How do they do it? No legs, arms, fins, wings. Talk about minimalism!
“Snakes are exceptionally versatile animals and can use their slender, highly articulated, near-continuum bodies to move through almost any environment “ ([1], p. 1)
The Terradynamics Lab at Johns Hopkins is studying how snakes move to inform the design of robots. This fall they report a study of 3D movement, snakes climbing a step [1]. The research observed Kingsnakes (Lampropeltis Mexicana) in a laboratory challenge. The detailed observations reveal the process as the snakes climbed over the step.
The experiments show that these snakes move in a “partitioned gait”, with three different body sections, that travel down the body as the snake gets over the step.
“The snake’s partitioned gait, with three body sections that move in different planes (two horizontal and one vertical) and travel down the body…” ([1], p.8)
It’s more complicated than this, because the details depend on the surface. On a slippery surface, the snake wriggles adjust. And for a higher step up, the “cantilever” adjusts to the situation.
It’s all very elegant and cool, as anyone who has carefully watched a snake will know.
The point, of course, it to try to use this understanding of how snakes do it to create robots with similar capabilities. The current version looks sort of like a railroad train, or long, articulated truck. But with snakey smarts, it can climb steps
To date, the robot is still nowhere near as competent as the snake. But this work shows that careful observation can lead to really cool biomimetic robot designs.
“The animal is still far more superior, but these results are promising for the field of robots that can travel across large obstacles” (Professor Chen Li, quoted in [2])
Nice work, all.
- Sean W. Gart, Thomas W. Mitchel, and Chen Li, Snakes partition their body to traverse large steps stably. The Journal of Experimental Biology, 222 (8):jeb185991, 2019. http://jeb.biologists.org/content/222/8/jeb185991.abstract
- Chanapa Tantibanchachai, By studying snakes, engineers learn how to build better robots in Hub, February 18, 2020. https://hub.jhu.edu/2020/02/18/snake-robots-799-em1-art1-rel-science/
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