Improvement of component mode synthesis model for vibration analysis of hard disk drives using attachment modes

Abstract

I improved the component mode synthesis (CMS) model for free and forced-vibration analyses of hard disk drives using attachment modes. The convergence and the accuracy of the proposed CMS model was improved substantially by applying an attachment mode to a FDB shaft and a pivot shaft in the stationary part model. Different formulations were used for the FDBs and the pivot bearings because of their different damping properties. In the proposed formulation, additional general coordinates corresponding to the attachment modes of the FDB shaft are introduced into the system coordinates; on the other hand, the attachment modes of the pivot shaft moderate the stiffness and damping properties of the pivot bearings. To check the improvement of the convergence and the accuracy, I performed the free and forced-vibration analyses using the previous and proposed CMS models and a full finite element (FE) model. The convergence of the natural frequencies and the frequency response function (FRF) of the disk/spindle system were extremely improved. Moreover, the FRF of the head actuator better matched the full FE model than the previous CMS model when the same number of component modes are used.

Modelling and Simulation of the Coupled Rigid-flexible Multibody Systems in MWorks

“…And the values of other modal coordinates are smaller and smaller, indicating less energy contribution. The variation tendency is complied with the modal superposition theorem and energy criterion [11] . The obvious vibration can be found in simulation result of the coupled rigid-flexible dynamics.…”

“…The mode shapes in modal neutral file, which contain the interface constraint modes, are revised effectively after modal truncation. So the Craig-Bampton method is more accurate and has been widely used in engineering [10][11][12][13][14] . But the software, just like ADAMS, mainly focuses on modeling and simulation of the pure mechanical system and lacks support of multi-domain physical systems.…”

“…In order to model and simulate the mechatronic products composed of mechanical, electronic, hydraulic, and control engineering systems, the co-simulation should be performed with other software such as Matlab/Simulink®, LMS.AMESim®, etc. In this paper, the FlexibleBody model is developed based on the component mode synthesis (CMS) and the improved Craig-Bampton method [9,11] . An external C function MNFParser is programmed to get the mode shapes data in the model.…”

Experimental and parametric studies of 0.85-in. hard disk drives spindle motor vibration

“…Such method can also be generalpurpose for arbitrary rotor geometry (Tseng et al 2005) or special-purpose for disk drive applications (Tseng et al 2003;Hasegawa et al 2003;Eguchi and Nakamiya 2006;Eguchi 2007). For example, an in-house spindle model developed at the University of Washington (Tseng et al 2003) is a special-purpose model focusing on disk drive applications.…”