Engineers at California Institute of Technology and ETH Zurich have come up with robots that are capable of self-propulsion without making use of any power supply, servos, or motors. Instead, these first-of-their-kind gadgets paddle through water as the material they are constructed from deforms with the change in temperature.
Newly Developed Robot Depends on Flexible Polymer
This work blurs the boundary between robots and materials. In these self-propelled devices, the material itself makes the machine function. Daraio, professor of mechanical engineering and applied physics in Caltech’s Division of Engineering and Applied Science states that our examples exhibit that we can make use of structured materials that cause deformation in response to various environmental cues so to control and propel robots. Daraio is the corresponding author of a paper that unveils the robots. The research has been published on the Proceedings of the National Academy of Sciences.
This new system of propulsion depends upon the strips of a flexible polymer that is curled when cold and stretches out when it is warm. The polymer is positioned in such a way that it activates a switch inside the body of the robot, which is, in turn, attached to a paddle that rows it forward like a rowboat.
The switch is being made from a bistable element, which refers to a component that can remain stable in two distinct different geometries. In this case, it is being built from strips of an elastic material that, when pushed on by the polymer, snaps from one position to another position.