Electromechanical modeling of actuator dynamics in a load/unload disk drive

A modeling technique is presented that provides a convenient and effective means to simulate the behavior of a load/unload disk drive actuator during loading and unloading. The technique uses the PSPICE electric circuit simulator, with the mechanical properties of the actuator and ramp system described by equivalent electronic circuit elements. The model uses a piece-wise continuous approach to incorporate the changing friction forces acting on the actuator. Simulation of the drive circuits, and bidirectional coupling between the mechanical and electronic domains is provided by the model. Modeling results are presented and compared to measurements taken on a prototype disk drive.