Underwater Robots for Cleaning and Inspection of Underwater Structures

Abstract

Maintaining underwater structures, e.g., bridge pylons, wharf piles, and underwater pipes, is challenging because of strong and unpredictable water current, low visibility, and awkward pose of divers during cleaning with high-pressure water-jet. This chapter presents an autonomous underwater robot developed for removing marine growth that covers the surface of underwater structures, and then conducting inspection and condition assessment. Design considerations and enabling technologies developed and implemented into the robot system will be presented, including SBL-SONAR-based navigation, stabilization, and vision-based 3D map building. Extensive testing of the robot in a lab setup and at various bridges was conducted to verify the robotic system. Results and lessons learnt will be discussed.