Cost-Effective Bridge Safety Inspection Using Unmanned Aerial Vehicles (UAVs)

Abstract

This report presents the results of a study on the use of unmanned aircraft systems (UAS) in bridge inspections. A detailed literature review was conducted to assess and document the current state of knowledge on the use of UAS in structural inspections and related engineering applications. A particular focus was on related work done by various state DOTs. Given the technical specifications and findings documented in the literature review, an item-by -item review of bridge inspection manuals was then performed to assess which elements of a bridge inspection could potentially benefit from use of UAS. Additionally, various categories of UAS and payloads were evaluated for bridge inspection. A small multicopter UAS was acquired and used to collect ultra-high-definition video and still imagery of a large bridge in Independence, Oregon. The imagery was reviewed by project team members and ODOT bridge inspectors. The results of the Independence Bridge inspection are presented, along with recommendations for further work. The study identified several challenges on the use of UAS for bridge inspection, including the need to capture very high resolution imagery, and problems due to strong wind and poor lighting conditions.