A device has been developed that is capable of relatively lengthy unattended operations and high sampling frequency of underwater environmental data anywhere in the world. The Bio-Optical Physical Pop-Up Environmental Reconnaissance System (BOPPERS) is housed in a trawl-resistant case that has been field-tested to 90 m.
A bottom-mounted, upward-looking, acoustic Doppler current profiler monitors currents of an entire water column. A tethered sensor platform is released from the base and rises to the surface at pre-determined intervals to continuously collect data such as water temperature, salinity, pressure, waves, and optical properties throughout the water column. Once the sensor platform reaches the surface, the data can be transmitted in near real time via a variety of means, including Iridium global satellite communication, radio, or local cellular. Once transmission is complete, the sensor platform is retracted back into the protective housing underwater.
BOPPERS can conduct about 120 water column profiles on a single charge. The system features an advanced energy-efficient winching system, and anti-fouling mechanisms for long and efficient sensor life. The sensor payload is highly customizable to accommodate an array of physical and bio-optical sensors, and BOPPERS could even act as a communication gateway for other sensors in the area.
BOPPERS features custom-designed hardware and a software control system developed to integrate all the sensors, data flow, storage, and transmission. Its programmable, dynamic configuration enables event scheduling.
The base and profiling unit is electrically isolated; computers communicate via inductive coupling, enabling event coordination and synchronization, as well as real-time updates to the system configuration. An inductive charging system is also employed to recharge the profiler batteries from the larger bank of batteries in the base unit to achieve a maximum power budget.