A lizard-inspired active tail enables rapid maneuvers and dynamic stabilization in a terrestrial robot

We present a novel approach to stabilizing rapid locomotion in mobile terrestrial robots inspired by the tail function of lizards.We built a 177 (g) robot with inertial sensors and a single degree-of-freedom active tail. By utilizing both contact forces and zero net angular momentum maneuvering, our tailed robot can rapidly right itself in a fall, avoid flipping over after a large perturbation, and smoothly transition between surfaces of different slopes. We also use a modeling approach to show that a tail-like design offers significant advantages to other alternatives, including reaction wheels, when the speed of response is important.