Control of a micro-actuator for hard disk drives using self-sensing

This paper describes control of a micro-actuator for hard disk drives using self-sensing actuation. The self-sensing actuator using electrical bridge circuit can measure either strain or time rate of strain in the actuator. These sensing signals correspond to the tip slope of the actuator and the time rate of tip slope of the actuator. The usefulness of the self-sensing actuation technique is experimentally verified by actively damping the vibration in a micro-actuator.