The growing number of older bridges has resulted in an increase in structural flaws, demanding frequent inspections and maintenance. Structural degradation accelerates post-damage recovery, emphasizing the necessity of preventive interventions. The use of Uncrewed Aerial Vehicle Systems (UASs) for bridge inspections represents a significant development in structural health monitoring (SHM). Traditional inspection methods are labor-intensive, time-consuming, expensive, and require access to high or difficult-to-reach areas, posing safety risks to inspectors. This study focuses on identifying drones that can efficiently support bridge inspection activities. Key factors influencing UAS selection include flight performance, flying modes, cost, sensor capabilities, payload capacity, and controller communication. The primary objective of this paper is to provide guidance to inspectors and transportation agencies regarding the capabilities and limitations of commercially available drones. It also outlines potential cost considerations associated with drone selection, including pilot skill level, platform cost, and sensor integration. These factors may vary depending on the type and complexity of the bridge being inspected. By addressing these aspects, this paper aims to assist decision-makers in making informed choices regarding the use of UASs for bridge inspection applications.
Energy harvesting is an emerging approach that supports the generation of renewable and clean energy, while also augmenting the durability and stability of infrastructure. The paper aims to review applicable energy harvesting systems deployed in various types of infrastructure, including roads and bridges, for applications such as photovoltaic noise barriers, photovoltaic cells, piezoelectric devices, and thermoelectric units. The harvested energy can be utilized to generate electricity, power wireless sensors, melt ice, and provide heating or cooling, while also assisting in monitoring structural conditions. Each energy harvesting technology is described in detail, covering operational principles, application scenarios, prototype development, and key findings from the literature. Economic feasibility studies are also examined to allow for a comparative assessment of energy output, production costs, and cost-effectiveness. This review provides a comparative feasibility framework integrating energy performance, levelized cost of electricity, payback period, and technology readiness levels for infrastructure-based energy harvesting systems.