Soft Snake Robot Uses Programmable Metamaterials for Improved Slithering

Harvard University researchers introduce a snake-inspired soft robot that is faster and more precise than its predecessor. They made the robot using kirigami, which is a Japanese paper craft that uses specific cuts to alter a material's properties. As the robot stretches, the kirigami surface “pops up” into a 3D-textured surface, which grips the ground like snake skin. The first-generation robot used a flat kirigami sheet wrapped around an elastomer actuator, which transformed uniformly when stretched. In the new version, the kirigami surface is rolled into a cylinder, with an actuator applying force at two ends. If the size of the cuts are chosen carefully, the skin can be programmed to deform at desired sequences. This programmable shell improves the robot's speed and accuracy.