Shallow water expendable and trawler safe environmental profilers

A prototype Shallow Water Expendable Environmental Profiler (SWEEP) for rapid environment assessment has been developed and tested by SACLANT Undersea Research Centre in collaboration with the University of Rhode Island Department of Ocean Engineering. The SWEEP system is intended for autonomous vertical profiling of acoustic, optical and physical properties of the water column and seafloor in depths down to 100 m. It is designed for data return and control via cellular phone or worldwide satellite packet communication while on the surface. The first prototype is an anchored profiler that uses an integral buoyant winch and sensor package to profile from the bottom up to the surface. The system is modular in design, allowing modules to be reused in new deployment alternatives. Already being planned is a Shallow water Environmental Profiler, in Trawl safe, Real time configuration (SEPTR). SEPTR is a bottom-up profiler with added ADCP, tide/wave gage and extended duration battery packages in a recoverable trawler safe housing. The design duration for the SWEEP is one month or 100 profiles in 100 m water depth. The design duration for SEPTR is 3 months or 360 profiles in 100 m. The profilers make use of new low cost, high performance sensors that include the following: 3-axis acceleration and magnetic field sensors; conductivity, temperature and pressure sensors; ambient light/ optical attenuation sensors; ambient noise and current sensors; seafloor acoustic sensors; DGPS navigation sensors. Two way communication of data, position and control allows profile results to be returned in real time, and operational commands, profile schedules, and DGPS correctors to be sent to multiple profiler instruments. Complete profiles will also be stored on board for recoverable units.