Review and Assessment of Technical and Legal Challenges in Application of Unmanned Aerial Vehicles (UAVs) in Monitoring and Inspection of Bridges

Abstract Intelligent Transportation Systems (ITS) initiated a paradigm shift in the operation and management of transportation infrastructure by automating data collection, processing, and management. The drive towards using robotics to automate operational tasks in infrastructure management has gained significant momentum in recent years, with the introduction of Unmanned Aerial Vehicles (UAVs), widely known as drones, being a notable milestone in this endeavor. UAVs reduced cost, time, and labor for tasks such as bridge monitoring while accelerating speed and precision such as structural scanning. Although not explicitly classified within the existing ITS categories, UAVs are becoming widely acknowledged as a valuable tool for improving the intelligent operation and management of transportation systems. Their potential to gather and transmit data in real-time offers new opportunities for more accurate and timely decision-making, as well as improved safety and efficiency within transportation infrastructure. Nevertheless, significant concerns remain regarding the use of UAVs, particularly in busy highways or densely populated metropolitan areas. Engineering and technical challenges, privacy and safety concerns, potential liabilities, and audio-visual disturbance for the public are among the issues that have impeded the widespread adoption and full integration of UAVs as complementary tools for ITS. This paper conducts a comprehensive review of the potential applications of UAVs for infrastructure and bridge structural Health Monitoring (SHM), while also evaluating the challenges associated with their utilization in this context. Furthermore, the paper discusses the ramifications of these challenges and emphasizes the areas that necessitate further attention and investigation by future research.