Integrated on-site inspection and repair wall-climbing robot of concrete cracks

Concrete infrastructure maintenance for vertical structures remains constrained by the separation between crack inspection and manual repair, which is labor-intensive, hazardous, and inefficient. This paper presents an integrated on-site inspection and repair wall-climbing robot (IOIR) for concrete cracks, combining crack detection, quantification, task generation, and robotic sealing within a unified workflow. The robot integrates negative-pressure adhesion, a modular climbing mechanism, an onboard lightweight HrSegNet-B32-AD segmentation network, and a compact 3-DOF repair module. Pixel-wise crack masks generated onboard support accurate geometric measurement and automated repair trajectory planning for sealing. Full-scale wall experiments demonstrate stable adhesion, reliable locomotion, precise trajectory tracking, crack-width relative errors of 0.53% and 1.49%, mean coverage of 98.6%, underfill of 1.4%, and coverage uniformity of 96.8%. These findings show that IOIR can effectively connect inspection with field repair, providing a practical automated solution for high-access concrete infrastructure maintenance and future robotic maintenance applications.