On non-linear response of head-disk interface to wavy excitation

The manufacture of rigid disk magnetic media requires information about the permissible out-of-flatness of disk surface. The scale of wavelengths of deviations range from once-around runout to surface roughness wavelengths. The purpose of this paper is to describe the results of numerical simulations designed to shed light on this issue and of related experiments using an improved laser Doppler measurement technique.