Disk Drive Pivot Nonlinearity Modeling Part II: Time Domain

This paper describes studies done at HP Labs on the actuator pivot bearing nonlinearity of a small disk drive. Part I of this paper presents a frequency-domain approach, using the swept-sine /describing function method, to obtain a model for this nonlinearity. Part II presents several additional models and discusses a time-domain approach, comparing simulated and lab measured torque versus displacement hysteresis curves. Using the measured and simulated time and frequency responses as a guide, the designer can iteratively improve the model of the system and verify the correctness of the measurements