Infrared-based point cloud reconstruction for heat loss detection in a virtual reality environment

Structure from Motion (SfM) is a photogrammetry technique with diverse applications, such as surveying, mapping, and inspection. It facilitates remote assessment of large systems by converting visible spectrum images into threedimensional (3D) point clouds. Recent advancements have extended SfM to employ infrared (IR) images, enabling the detection of issues such as water infiltration and sub-surface defects that can cause energy loss in a building. Combining IR-based SfM with unmanned aerial vehicle (UAV) technologies yields high-definition 3D point clouds that can be used in a virtual reality (VR) environment. This study showcases the application of the SfM-IR-UAV method to create 3D virtual models of selected buildings in the University of Massachusetts Lowell's campus to assess energy loss. The 3D virtual models are made accessible via a VR platform to develop a remote inspection and maintenance tool. The VR platform also holds the capabilities to mark abnormalities in the structure, which can later be used for informing renovation or repair. The proposed approach simplifies remote assessment, reducing costs and operational risks. While this research focuses on energy audits, its outcomes extend to diverse domains. Further development holds the potential to expedite nondestructive evaluation and enhance structural health monitoring in civil and mechanical engineering, utilizing the 3D point cloud thermal model within a VR environment.