Method and apparatus for predicting a head crash in a disc drive

摘要

A head crash in a hard disc drive is predicted by periodically measuring a head-disc contact energy level on an actuator arm supporting the head and identifying a predetermined change in the energy level between at least two energy level measurements. The head-disc contact energy level is measured by a positioning microactuator on the actuator arm, and comparing that energy level to a threshold established during an earlier or selected contact start-stop cycle. A circuit is coupled to the microactuator and is periodically operable to identify a magnitude of contact energy. An indicator is coupled to the circuit and responsive to the representations to indicate presence of symptoms of an impending crash.