Development of an exterior wall inspection system using pulsed water jets

In this study, we have developed a non-destructive inspection system for detecting external wall tile delamination by incorporating a pulse water jet impingement force into a suspended apparatus. The delamination inspection using a pulse water jet offers flexibility in adapting to variations in the distance between the inspection device and the inspection surface, a challenge inherent to the suspended apparatus. Furthermore, the delamination inspection using a pulse water jet exhibits exceptional safety and cost-effectiveness. Using this inspection system, we conducted a delamination detection test on tiles with delaminated mortar and were able to detect it. The inspection speed of this apparatus is approximately 10 centimeters per second in horizontal movement, allowing for an inspection rate of roughly 18 square meters per hour for tiles with a 50-millimeter spacing. This inspection speed is comparable to that achievable by human operators. Moreover, the system can perform inspections at heights of up to 30 meters above ground level. This inspection system has the potential to address the issue of labor shortage by facilitating automation.