Remote-controlled Rust Assessment System for Weathering Steel

Weathering steels possess excellent corrosion resistance due to the precise protective rust layer formed on the surface, which suppresses further corrosion. Due to its superior weatherability, weathering steels are used for bridges, external walls of buildings, and outer surfaces of railroad vehicles. However, weatherability cannot fully inhibit corrosion due mainly to a high salt level in the atmosphere. Therefore, the rust condition of weathering steels must be regularly inspected and evaluated. Currently, the rust conditions of weathering steels are assessed by visual inspections. The drawbacks of this method are that it requires inspectors with expertise and lacks accuracy and repeatability as it is a subjective assessment. We have developed a system capable of quantitatively assessing rust conditions of steels. Previously we proposed a method to evaluate rust conditions of weathering steels by capturing images of rust with multiple lighting devices and cameras, and subsequently processing the captured images. In that study, we fabricated an image capturing device and confirmed that rust conditions of weathering steels could be evaluated accurately. Herein we report a modified image capturing device, which is smaller, lighter, and can be operated remotely. Our modified image capturing device can travel upwards, downwards, and horizontally. Additionally, it can be operated by a remote control from 80-m away.