Research on Screw Thread Vision Measurement

Abstract

Screw thread, as the most basic and widely used mechanic element, has many traditional methods to verify its dimension consistency. Machine vision technology is gradually applied to inspect screw thread in fastener industry because of its fast, precise and repeatable features. Based on analysis of the features and problems of previous vision measurement methods, this paper provides calculation, analysis and simulation of screw thread’s 3D mathematic model, and finally provides corresponding algorithm to correct calculation error resulting from shading effect of backlight projecting.