Fiber-Crawling Microrobots

Microrobots that crawl along fibers can work as linear actuators and as active components in assembling 3D structures from microscale parts. They are also a potential topic for microrobotics demonstrations and competitions, analogous to contests in the macroscale rope-climbing robot domain. In this work, we briefly review cable-traveling robots, then demonstrate a magnetically driven wire crawler where the wire provides the driving power, causing the robot to vibrate. Stick-and-slip friction creates motion along the wire. We discuss scaling down both the magnetic actuator and the flexible contacts that produce stick-and-slip motion. Two types of compliant frictional contacts are demonstrated: a thin plastic film, and at a smaller scale, anisotropic microbristles made from natural materials. Lastly, we discuss a path to further miniaturization.