Issue 51

K. Li et alii, Frattura ed Integrità Strutturale, 51 (2020) 386-397; DOI: 10.3221/IGF-ESIS.51.28 394 R ESULTS AND DISCUSSION Defect detection he structure contains depressions, holes, and crack defects caused by fatigue loading. The Region of Interest (ROI) of each defect point cloud image is extracted, and the defect detection is performed according to the formula (4) and the formula (5), as shown in Figure 11. Figure 11 : Defect detection result. The specific detection results of each defect are marked in Figure.11, including the size and elevation data information. Analysis of results The measurement results are obtained based on Digital Image Correlation (DIC ） technology and the yernier caliper detection method based on traditional detection technology respectively. The test results and analyze test performance is compared. The detection method based on DIC technology needs sufficient illumination. Moreover, structural damage information needs to be obtained in conjunction with digital image correlation techniques. And the conventional measurement method needs a professional inspector. The scanning device designed in this study is consistent with the defect detection results obtained by each detection means. The rationality and reliability of the system are fully proved. At the same time, the scanning device designed in this study is superior to other detection technologies in performance. The comparison of performance as shown in Table 1. The data in Table 1 shows that the traditional measurement method and the flaw detection instrument combined with DIC have higher requirements on the light source, lower objectivity and efficiency, and it is difficult to capture the elevation information of the defect. The 3D laser scanning system developed in this paper realizes the modeling of the measurement structure. It can achieve more accurate detection results under any condition. And it has the advantages of wide measurement range and high accurate of detection. It has no blind spot area and high detection efficiency. In this comparative analysis experiment, the 3D laser scanning system showed stronger environmental adaptability and higher detection efficiency. The developed scanning system has high scanning accuracy and fast scanning speed. It can T