Development of a Wire-Guided Imaging Device for Inspection in Confined Spaces of Municipally Managed Bridges

Abstract

 In recent years, the use of advanced technologies in road bridge inspections has been promoted, and even in municipal bridge management, image analysis technologies and digital inspection records have begun to be introduced. However, for bridges with narrow under-girder spaces, human access is difficult, and image acquisition methods remain a challenge. To address this issue, technologies such as radio-controlled boats have been developed, but their adoption has been limited due to problems such as susceptibility to water flow and high costs. Therefore, this study aims to improve the efficiency of bridge inspections in confined spaces by developing a guide-wire-based imaging system that enables low-cost and stable image capture. Field trials of the prototype revealed issues related to operability and platform inclination. To address these, an improved model was produced, and subsequent field tests confirmed enhanced operability and stable imaging performance. These results demonstrate the applicability of the proposed system to inspections of confined spaces in municipally managed bridges.