Piezoelectric actuator and shock sensor

The present invention relates to shock sensing in a dual-actuator servo system for hard disk drives. More particularly, the present invention is directed to use of a piezoelectric element for both positioning of the actuator and for sensing shocks imparted to the hard disk drive assembly. A dual purpose piezoelectric element utilized in a disk drive for fine positioning of the head assembly relative to the surface of a disk and for sensing shocks and other vibrations. When a shock is sensed by the piezoelectric element that exceeds a predetermined threshold value, write operations are halted to prevent a write operation occurring at an incorrect location on the disk.