- Piotr Wasylczyk
- Mikołaj Rogóż
Have you ever observed a caterpillar crawling on a leaf? A 15 mm long soft robot, that is capable of mimicking movements of a caterpillar was recently built using a new class of smart materials. The monolithic robot, made of soft polymer, capable of reversible, elastic deformation is powered and controlled by light. The robot’s body is made of liquid crystalline elastomer (LCE) which forms the soft body, and at the same time acts as a monolithic muscle. Using the technology developed in collaboration with the European Institute of Nonlinear Spectroscopy (LENS) in Florence, we can pattern this material at the single millimeter scale and thus control the molecular order in the elastomer film to induce a curling deformation under illumination. A laser beam is used to activate different segments on the robot, driving it in the stepping gait. Scanning the laser beam along the robot’s body activates the muscle sequentially and allows it to crawl, as the deformation propagates from “tail” to “head”. Apart from walking on flat surfaces and climbing a slope, the soft micro-robot can push loads as heavy as ten times its own mass. Thanks to its soft, adaptable body, it is also capable of squeezing through narrow slits. The micro-robot’s walking strategy is directly inspired by the sequential body deformation found in living caterpillars. This may one day help us understand different locomotion mechanisms in the micro-world and perhaps implement them in efficient robotic systems. We hope that the new generation of elastomer materials will soon allow us to build tunable optical and photonic structures, as well as light driven micro-robots that can swim, dive, and maybe even fly. The soft, light powered elastomers are also promising candidates for actuators in other nano- and micro-scale applications – they can be 3D printed with sub-micrometer resolution with direct laser writing.