A new approach for detecting and grading blistering defect of coatings using a machine vision system. (15th November 2022)

• Record Type: Journal Article
• Authors: Moradi, Nadia; Gorji Kandi, Saeideh; Yahyaei, Hossein
• Is Part Of: Measurement. Volume 203(2022)
• Publication Date: 2022-11-15
• Subjects: Degree of blistering -- Machine vision -- Surface coating -- Quality control -- Image processing -- ISO 4628-2; Weights and measures -- Periodicals; Measurement -- Periodicals; Measurement; Weights and measures; Periodicals; 530.8
• DOI: 10.1016/j.measurement.2022.111954
• Languages: English
• ISSNs: 0263-2241

Abstract

Highlights: Blistering is a frequent surface coating defect and is mostly assessed visually. A new system including an image acquisition setup in ambient lighting was designed for instrumentally detection of blisters. A new algorithm for detecting blisters was proposed based on image analysis. A grading algorithm of blisters based on features extracted from ISO 4628-2 calibration images was presented. The proposed algorithm can accurately detect the degree of blistering of coatings compared to visual evaluation. Abstract: Blistering is a frequent coating defect and is mostly assessed visually. In this research, a new system including an image acquisition setup in ambient lighting, a new algorithm for detecting blisters visible to normal corrected vision as well as those with a diameter of 5 mm and more, and a grading algorithm of blisters based on features extracted from ISO 4628-2 calibration images is presented. This system has efficient performance in the detection and extraction of blisters in images of achromatic colored gloss paints with both artificially and naturally made blisters. It can detect high-frequency blisters in a single shot and assess the degree of blistering of coatings with a 95 % precision compared to industrial inspectors' visual evaluation. These findings show its capability as an alternative to manual inspection for inspecting the blistering defect of coatings during production and service.