The Aerodynamic Stabilization of Video Discs_

This paper describes the general principles behind the aerodynamic stabilization of flexible video discs as demonstrated by the Thomson-CSF stabilizer, and a modified version investigated by Zenith. It is shown that aerodynamic stabilization is a very nonlinear process and is governed by the stiffness of the air film between the disc and the stabilizer. For the stabilizers under discussion this stiffness is inversely proportional to the cube of the gap between the disc and stabilizer, which necessitates the use of a small gap. Depending on disc thickness and hence on disc stiffness, this gap may be 2-8 mils in excess of the disc thickness. In the modified version the lower CSF stabilizer is replaced by a flight deck. It is shown that the flight deck acts as a prestabilizer which produces a two-to-three fold improvement in stability for the same air gap. Experimental data and computer calculations are organized in a form which provides definite design criteria for the selection of an optimum system.