Modeling of hard disk drives for vibration analysis using a flexible multibody dynamics formulation

This paper presents a flexible multibody dynamics formulation to analyze the vibration of hard disk drives. The formulation is applied in analyzing the vibration of the voice coil motor (VCM)-actuators assembly and the disks-spindle system. There are flexible components as well as rigid bodies in the system. Governing equations of motion of the VCM-actuators assembly and disks-spindle system are derived by using a Lagrangian formulation. Elastic deformations of flexible bodies are described by modal coordinates from a finite-element (FE) formulation. After obtaining the formulations, modal analysis and nonoperating shock response are analyzed. The numerical analyses are significantly faster compared to a full FE approach and is potentially useful when the system requires repeated analysis of the model of the entire system when certain design variables are changed.