The broader impact of this Small Business Innovation Research (SBIR) Phase I project is to protect marine ecosystems against invasive species and to help the shipping industry reduce its greenhouse gas (GHG) emissions. Marine invasive species are considered to be one of the greatest threats to marine and coastal biodiversity worldwide, second only to habitat loss. Keeping the oceans healthy is essential to preserve the employment, development and growth of the ocean economy. This is particularly relevant in the United States, where the marine economy contributes nearly $400 billion to the nation's gross domestic product with 40 percent of the population living in coastal counties. One of the main vectors for the transfer of marine invasive species is the biofouling on ship hulls, described as the undesirable accumulation of microorganisms, plants, algae and animals on the submerged hull. A second impact of biofouling is to increase the drag forces on the hull, resulting in an increase of the ship's fuel consumption and GHG emissions in the atmosphere. This project advances a system for in-water inspection of ship hulls with a fleet of Unmanned Underwater Vehicles (UUVs). The automated underwater inspection system will provide maritime stakeholders with biofouling data to optimize hull cleaning schedules, validate compliance with regulations, thereby improving ship performance and ecosystem health. This project develops a system leveraging a UUV fleet that forms an arch operated from a vessel (e.g. power boat, crew vessel) located at one of the arch's extremities. It can inspect hulls as ships enter or leave ports without having to be immobilized. The UUVs exchange data wirelessly between each other and with the surface, enabling autonomous coordinate inspections without tethers but under human supervision. An advanced positioning system and control scheme will be implemented to enable accurate localization without GPS and precise operation in the vicinity of the hull. This project will conduct in-water experiments to validate the performance of the positioning system and control scheme. The outcome of the project will be a proof-of-concept where a fleet of two UUVs inspect the hull of a vessel, demonstrating that the inspection system is fast, practical and repeatable. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
