High-resolution UAV cameras let inspectors find 0.2 mm cracks from safer distances
Kyuden Droneservice has upgraded its drone inspections to detect tiny structural cracks from safer standoff distances. The Fukuoka-based surveying and inspection company now uses Phase One P3 iXM-100 and iXM-GS120 cameras to improve image detail, reduce flight risk and expand the infrastructure work it can perform across Japan.
The company had previously used a standard 4K camera. To meet customers’ 1 cm ground sampling distance requirement, it had to fly at about 37 meters above ground level, which did not match the safe altitude needed for some jobs. The requirement was tougher for building inspections. Japan’s Building Standards Act requires cracks larger than 0.2 mm in structures to be repaired, and clients often ask inspectors to identify cracks above that threshold. Safety limits kept the UAV farther from structures, preventing the company from achieving the required resolution and leaving it with only rough inspection capability.
The iXM-100, a 100-megapixel camera with a back-illuminated medium-format sensor, changed that operating envelope. Kyuden Droneservice can now achieve a GSD of 0.46 cm at an altitude of 100 meters, giving pilots more tolerance for flight-path deviation and improving safety. The company flies missions with in-house automatic navigation software. During inspections, cracks are easier for pilots to see. During surveying, the UAV can capture wider areas from farther away while preserving detail through GNSS-supported workflows. Cracks larger than 0.2 mm can now be detected from 18 meters away, and the sharper imagery also makes AI-based crack detection easier in post-processing.
The higher-resolution system has also improved productivity. Using the iXM-100 for photogrammetry reduces flight time and the number of images required because each frame captures more usable detail. In some cases, total work time has been cut by about one-third. The company has used the system on road tunnel construction inspections in Osaka about twice a month, processing roughly 1,500 120-megapixel 3D images each time to compare terrain models and assess whether the road above the tunnel is sinking. It has also inspected a 150-meter chimney in just over half a day, taking images from 18 meters away at about 0.8 mm resolution. The result is a broader UAV inspection business with safer operations, faster data capture and a clearer path toward fully autonomous work, including future offshore wind turbine inspections from land rather than by boat.