Keisuke Shida

A Study on the Effect of Inspection Time on Defect Detection in Visual Inspection

In order to consider the visual inspection utilizing the peripheral vision, this paper examines the inspection times that affect defect detection. The fixation duration and the distance between defect and the fixation point are experimental factors in determining the inspection time. As the result, in case of a large sized defect, the detection rate is high regardless of the fixation duration and the distance between the defect and the fixation point. In case of a small sized defect, when the fixation duration is longer and the distance between the defect and the fixation point is closer, the defect detection rate is higher. Moreover, as the result of conducting multiple linear regression analysis about the experiment factors, it is obtained that judging from standardized partial regression coefficient of factors, higher defect size, less the distance between defect and the fixation point, the higher fixation duration, is proved to improve the defect detection.

A Study on Effective Methods of Visual Inspection for Reused-Parts by Inspectors

In order to promote recycling in the recycling industry, it is essential that suppliers perform a strict inspection before shipping the products using reused or recycled parts. The industry is facing pressures to further improve and standardize inspection quality and efficiency on recycled parts or products. This study thus developed an effective visual inspection method for products using reused parts by inspectors at Recycling Plant N, for assuring product quality. First, a survey was conducted to investigate the current situation at the subject plant. Secondly, another set of surveys was conducted for the 13 inspectors. The survey included a video analysis, a questionnaire survey analysis, and an analysis of eye movements using an eye-tracker, and after the analyses, the differences were specified. Thirdly, by considering the inspection method and inspection orders used by the experienced inspectors, appropriate inspection items, inspection order, and inspection method could be devised.