Micro shape memory alloy wire actuator applied for limited space

In order to output the necessary displacement in a micro/miniature mechanism, the length of a shape memory alloy (SMA) wire usually exceeds the limited space available. The cause of such a phenomenon was studied, and a new SMA wire actuator was developed. By means of this new actuator, the SMA wire can be distributed in three dimensional space . Theoretical analysis and experimental results indicate that, the new actuator not only overcomes both the drawbacks of SMA linear actuator and the ones of SMA spring actuator, but also owns better mechanical performance than the skeletal muscle. When it is used in the micro/miniature bio-robot, it can output the demanded force, displacement and actuating velocity at the same time.