In this paper, we speculate on a possible application of Liquid Crystal Elastomers to the field of soft robotics. In particular, we study a concept for limbless locomotion that is amenable to miniaturisation. For this purpose, we formulate and solve the evolution equations for a strip of nematic elastomer, subject to directional frictional interactions with a flat solid substrate, and cyclically actuated by a spatially uniform, time-periodic stimulus (e.g., temperature change). The presence of frictional forces that are sensitive to the direction of sliding transforms reciprocal, 'breathing-like' deformations into directed forward motion. We derive formulas quantifying this motion in the case of distributed friction, by solving a differential inclusion for the displacement field. The simpler case of concentrated frictional interactions at the two ends of the strip is also solved, in order to provide a benchmark to compare the continuously distributed case with a finite-dimensional benchmark. We also provide explicit formulas for the axial force along the crawler body.
|Titolo:||Liquid crystal elastomer strips as soft crawlers|
|Autori:||Desimone, A.; Gidoni, P.; Noselli, G.|
|Rivista:||JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS|
|Data di pubblicazione:||2015|
|Digital Object Identifier (DOI):||10.1016/j.jmps.2015.07.017|
|Appare nelle tipologie:||1.1 Journal article|