A shape memory alloy system suitable for use in any number of environments, including but not limited to latching and unlatching vehicle seat tracks. The control circuit reads the output from the output device to determine if the output indicates a valid mode. The memory may store a degree of active copresence. By fabricating the coupler from carbon-carbon composite, metallic shaft mating splines are provided with a coupler that has exceptionally high temperature capabilities, high strength, and can be impregnated with graphite or other dry lubricants to reduce frictional heat generation and reduce spline wear.