Three-Dimensional Geometry of Crimp

Abstract

Geometric torsion and curvature accurately describe three-dimensional forms of crimp. The usual parameters of crimp frequency and indices of amplitude or extensibility for idealized planar or helical crimp forms are expressible by specific relationships of geometric torsion and curvature. The more common, nonideal crimp forms are characterized by distribu tion statistics of these two fundamental parameters along the fiber. Mathematical techniques and analytical expressions were developed for describing crimp this way with data from an automatic crimp-measuring instrument and use of a digital computer. Examples are given from measurements made on several commercial man-made and natural fibers.