Automatic Thread Defect Examination System

Abstract

This article addresses a Thread Hole (TH) examination system capable of automatically examining a TH. We introduce a contact-based examination system with simple hardware. Our examination system examines TH defects by observing the torque generated when tightening the Inspection Device (ID) through the TH. A buffer with springs is utilized to overcome instances where the TH is not accurately aligned with the axis of the ID. The examination system observes the TH size utilizing a camera, then automatically performs an examination utilizing the optimal torque threshold associated with the TH size; in this way, our examination system is able to examine a TH regardless of its size. In this paper, the performance of the proposed system utilizing the optimal torque threshold is verified through experiments.