SMA actuated compliant bistable mechanisms

This article introduces the concept, analysis, as well as the design of shape memory alloy (SMA) actuated compliant bistable mechanisms. Compliant bistable mechanisms and SMA linear actuators have noteworthy advantages. When they are combined, not only their advantageous characteristics are preserved, but also some disadvantages can be eliminated. Thus, comparing to a stand-alone SMA actuator, SMA actuated compliant mechanisms have the advantages of requiring no input to stay at the stable positions, high repeatability in positioning, lightweight and simple control. Complexity in analysis, design, and control of SMA actuators and other shortcomings of SMA actuators, such as short output stroke and small output force, are either eliminated or improved.