System identification and controller design for dual actuated hard disk drive

摘要

This paper describes classical system identification and control design techniques for the dual actuated servomechanism of a hard disk drive. The dual actuated servomechanism consists of a electromechanical coarse actuator and a piezo-electric micro-actuator. The coarse actuator provides the motion required to move the read-write head from one data track to another, while the micro-actuator improves the tracking performance of the servoloop. The micro-actuator also reduces the response time for small seek-length. A simple design approach is adopted in this paper. The coarse actuator loop is first designed for basic performance and stability, using estimated state feedback. The compensator for the micro-actuator is then designed to achieve better performance of the overall system. Simulation and experimental results underscore the effectiveness of the design.