Crack Inspection Support System for Concrete Structures Using Head Mounted Display in Mixed Reality Space

Abstract

The number of concrete structures that are more than 50 years old is increasing. Since these concrete structures must be inspected periodically, automatic crack inspection methods are utilized, such as image processing to find shapes of cracks on the concrete surface. The crack inspection result needs to be corrected and confirmed off-line by an operator to verify that there are no missed defects or false positives. In this paper, we developed a crack inspection support system using a head-mounted display (HMD). The proposed system consists of building 3D models by spatial sensing, detecting and matching features of cracks from captured images, and finally superimposing and projecting detected cracks onto the real structure surface in a mixed reality (MR) space. Through experiments, we confirmed that the proposed system could acquire 3D data of concrete structures that can be measured easily in real time and onsite. In addition, it is possible for the operator to confirm the crack measurement analysis by comparing measured results with the actual structure in the MR environment. Thus, the proposed system unifies the previously separated processes of 3D data creation and analysis used in concrete structure inspection.