The design and experimental validation of an ultrafast shape memory alloy ResetTable (SMART) latch

Latches are essential machine elements utilized by all sectors (military, automotive, consumer, manufacturing, etc.) with a growing need for active capabilities such as automatic release and reset, which require actuation. Shape memory alloy (SMA) actuation is an attractive alternative technology to conventional actuation (electrical, hydraulic, etc.) because SMA, particularly in the wire form, is simple, inexpensive, lightweight, and compact. This paper introduces a fundamental latch technology, referred to as the T-latch, which is driven by an ultrafast SMA wire actuator, that employs, a novel spool-packaged architecture to produce the necessary rotary release motion within a compact footprint. The T-latch technology can engage passively, maintain a strong structural connection in multiple degrees of freedom with zero power consumption, actively release within a very short timeframe ( Keywords: shape memory alloy, T-latch, active latch, rotary actuator, high-speed latch, SMA spooling, SMA packaging