Patent ID: 8766564

Claim:
A method of activating a shape memory alloy (SMA) actuator, comprising the steps of: a) exposing the SMA actuator to an activation signal wherein the SMA actuator is responsive to the activation signal by a microstructure transformation to activate the SMA actuator; b) sensing an observable property of a portion of the SMA actuator or of a component in a drive-train driven by the SMA actuator wherein the observable property is indicative of an amount of motion delay between a beginning of the exposing of the SMA actuator to the activation signal and an onset of the activation of the SMA actuator; c) autonomously detecting a change in the observable property based on the sensing; d) autonomously determining a reduction in the amount of motion delay based on the detecting of the change in the observable property wherein the reduction in the amount of motion delay is caused by the activation of the SMA actuator; and e) autonomously determining the onset of the activation of the SMA actuator based on the determining of the reduction in the amount of motion delay.