  This paper presents a soft-robotic platform for exploring the ecological
relevance of non-locomotory movements via animal-robot interactions. Coral
snakes (genus Micrurus) and their mimics use vigorous, non-locomotory, and
arrhythmic thrashing to deter predation. There is variation across snake
species in the duration and curvature of anti-predator thrashes, and it is
unclear how these aspects of motion interact to contribute to snake survival.
In this work, soft robots composed of fiber-reinforced elastomeric enclosures
(FREEs) are developed to emulate the anti-predator behaviors of three genera of
snake. Curvature and duration of motion are estimated for both live snakes and
robots, providing a quantitative assessment of the robots' ability to emulate
snake poses. The curvature values of the fabricated soft-robotic head,
midsection, and tail segments are found to overlap with those exhibited by live
snakes. Soft robot motion durations were less than or equal to those of snakes
for all three genera. Additionally, combinations of segments were selected to
emulate three specific snake genera with distinct anti-predatory behavior,
producing curvature values that aligned well with live snake observations.
