Micro-robot Using Reversible SMA Actuator

Abstract

Reversible SMA (-RSMA), the so-called two way and all round SMA, is very convenient in fabricating a micronsized SMA actuator, because only one SMA material is needed for an SMA actuator. An active bending frame (-ABF) for a robot using a larger-sized RSMA sheet whose original shape was memorized round, was made and its shapes were analyzed experimentally and theoretically. Based on the theory, a homogeneous transformation matrix for the ABF was derived. A SCARA Type robot using 2 larger sized ABFs was made and was controlled by electrical current. Finally, it is shown that a thin film of reversible TiNi ally for a micron sized robot could be made by a magnetron sputtering method and by heat treatment methods, and that the frequency response of 7μm thick thin film of reversible TiNi alloy is about 5Hz.