SGER: Exploratory Research on Wet SMA Array Actuators

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

In this project we are investigating a scalable architecture for building hundreds and thousands of Shape Memory Alloy (SMA) actuators housed in a compact body. SMA filaments submerged in special fluids are arranged in matrix form, so that heat can be removed from and delivered to each of the SMA filaments rapidly and efficiently. With this matrix architecture, only 2N valves are needed for delivering fluids to each of N2 SMA array actuators. The architecture is therefore scalable for building a vast number of actuators: 20 valves for 100 array actuators, and 30 valves for 225 array actuators. In this exploratory project a test bed for testing 4 by 4 (16 axes) array actuators is being built in order to study the dynamics and control of the vast array SMA actuators as well as to investigate scalability of the design. The proposed method can be integrated with other energy sources, such as fuel cells, micro gas turbines, and internal combustion engines, for energy saving. These energy sources eventually produce heat as waste energy, which can be collected with fluids and used for activating the SMA actuators. This co-energy generation system has the potential to revolutionize the design of mobile robots, automobiles, and other mobile platforms. The vast number of SMA array actuators powered by a co-generation system would allow a mobile platform to perform highly complex, multifunctional tasks. Like biological creatures, robots will one day be able to run, leap, and fly, if the vast DOF actuator technology becomes available.