LQG/LTR control of a dual stage actuator hard disk drive with piezoelectric secondary actuator

High capacity of new magnetic material can be exploited only with a fine servo-positioning of the hard disk heads. This can be achieved by means of dual stage actuation, where the secondary actuator can be realized with different technologies. In this paper, the use of the LQG/LTR approach for the design of the controller for Hard Disk Drive with a piezoelectric secondary actuator is investigated. In particular, the case of absence of secondary actuator position sensing is addressed. An experimental platform for testing the developed control algorithms is presently under construction, and it has been employed to tune an accurate non-linear model of the hard disk drive with dual stage actuator. The controller performance is then evaluated by means of simulations on such model.