EXPERIMENTAL INVESTIGATION OF THE PROPERTIES OF A NOVEL COMPLIANT AIR BEARING MATERIAL HANDLING SYSTEM

Abstract

An air bearing materials handling system supports its load on two compliant runners having the form of oval cylinders moving along shallow concave rails. Air is supplied by manifolds integral with the rails through nozzles spaced at intervals in the rail surface. Loads up to 3 tonnes can be moved with an effective coefficient of sliding friction of about 1%. Developed by trial-and-error, the system has incompletely understood features. Two are: the role of the system geometry in providing load support; and the construction of the runners, which consist of layers of cellulose fibre tissue wound onto a core, and enclosed in a plastic cover. Exploratory research aimed at establishing the effect of these features on the load fraction supported by air pressure is reviewed. Flat surface equivalents instrumented for pressure surveys are developed to assess the role of the tissue, and to suggest alternatives. The load fraction is determined, and the response to asymmetric loading is investigated. The minimum number of tissue layers necessary for bearing action is identified, and the performance of compliant alternatives is explored. The review concludes with a discussion of the elements required of a mathematical model suitable for guiding design improvement.