Identifying building leakage with unmanned aerial vehicle assisted background oriented schlieren imaging

In 2024, air leakage from structures accounted for approximately 4% of the United States' energy budget. Repairing air leakage points in a building can lead to increased energy efficiency, improved indoor air quality, and overall occupant comfort. The background-oriented schlieren (BOS) technique has been used previously to identify leak points, but these measurements have been primarily constrained to the ground. By attaching a high-resolution camera to an unmanned aerial vehicle (UAV) and utilizing improved optical flow algorithms, UAV assisted BOS imaging provides three-dimensional freedom when locating air leakage points around a building.