Analysis of lay characteristics of three-dimensional surface maps – B. Boudreau and J. Raja

Abstract

This paper describes a technique which can characterize the surface lay structure contained within a three-dimensional surface map. The technique is based on a generally known fact, that two, closely spaced, parallel profiles will appear shifted whenever the dominant lay direction is not perpendicular to the profile direction. The cross-correlation function is utilized to evaluate these apparent shifts. It will be shown that the functional relationship of these shifts is a characteristic of the lay pattern. Simple linear models are then applied to the shifts to quantify the lay characteristics. The resulting models can be used to extract lay angles and curvatures which correlate directly to the manufacturing process used to create the surface.