Analysis of Friction-Induced Self-Excited Vibration of Contact Recording Head Slider

This paper presents a theoretical analysis of the friction-induced self-excited vibration of a contact head slider that is one of the head design candidates for future high density recording disk storage. In order to understand the fundamental destabilizing mechanism of the contact slider, the slider-suspension system is modeled as a two-degree-of-freedom (DOF) system. The instability of this system is caused by the asymmetry of the stiffness matrix due to the friction force. The unstable region of this system is examined in terms of the normal and angular natural frequencies, frictional coefficient, slider mass center position and the contact and suspension stiffnesses. The destabilizing mechanism of friction force is made clear by illustrating the mode shape of the complex number. From this model, it is found that the system always becomes stable if the center of mass of the slider is located ahead of the torsional center of slider suspension.