Obtaining measurements from the ocean water column and seabed is challenging. Oceanographic buoys have been used for applications that require persistent measurements from a single location for many years. However, the buoys are designed to withstand worst-case weather scenarios and therefore usually weigh over hundreds of kilograms and require specialized vessels and cranes to be deployed and maintained. If measurements from the water column are needed sensors at different depths need to be installed, and a communication system (cabled, or acoustic) needs to be in place. Alternatively, a winch mechanical system on the buoy can also be used to obtain water column profiles but, being exposed to seawater, corrosion and reliability become a serious challenge.
During RCN-funded MarTERA project OASYS, OsloMet has developed an innovative technology that can, in many cases, replace classic oceanographic buoys with a much simpler design with the potential to revolutionize how realtime in situ ocean measurements are acquired. The solution is a robotic float that can transmit realtime ocean measurements while on the surface using satellite, or mobile phone networks. The proposed system is unique because the floats can autonomously descend to the seabed. This has several advantages: i) it avoids being an obstacle to marine traffic and minimizes the risk of sabotage/equipment being stolen; ii) It allows to obtain measurements of the sea surface, but also of the water column, and seabed; iii) it can avoid high seas / extreme weather, which results in much simpler mechanical designs; iv) it minimizes the effect of biofouling, which minimizes the need of maintenance.
The technology developed during the project can have multiple applications in environmental monitoring of aquaculture and offshore wind projects, improving extreme weather alert systems, and climate and ocean research.