Design and Development of a Multi-rotor Unmanned Aerial Vehicle System for Bridge Inspection

To prevent the occurrence of bridge structural failure, regular bridge inspections are required to find the defects of bridges. Traditional detection methods are mainly carried out manually, which are cumbersome and unsafe. The objective of this study is to develop an unmanned aerial vehicle (UAV) for bridge inspection in a fully autonomous manner. In view of the characteristics of the bridge environment and detection principle, a hexarotor frame with an upward camera gimbal is specially designed. Complete control system, sensor system, and image processing system are integrated into the system on the Robot Operation System (ROS). In addition, position estimation and obstacle detection with multi-sensor fusion technique are proposed for obstacle avoidance, human-friendly control flying under the bridge environment without Global Position System (GPS). Compared with traditional bridge inspection method, UAVs will not be limited to space, which will simplify the inspection process, improve the inspection efficiency, guarantee personnel safety, and reduce the incidence of high-risk job accidents.