Current research status and key technological advances of underwater ship cleaning robots: A systematic state-of-the-art review

Ship cleaning is critical to maintaining vessel operational safety. With the growing demand for ship maintenance and advancements in mechanical automation, underwater ship-cleaning robots have been increasingly adopted in the sector, becoming a key research focus in underwater robotics and maritime engineering. This paper offers a comprehensive review of the development of underwater ship-cleaning robots from 2005 to 2025. It systematically summarizes the primary cleaning technologies, surface adhesion methods, chassis structures and drive systems, underwater target recognition, navigation techniques, and path planning algorithms currently utilized in these robots. The paper also examines the limitations and challenges they face, such as low cleaning efficiency, environmental pollution, limited flexibility, and high costs. In response, recommendations are made and future research directions and development strategies are outlined. These insights provide valuable guidance for maritime stakeholders.