Electromagnetic Velocity Profiling float: velocity and mixing measurements with adaptive sampling capabilities

PI: Szuts, Zoltan (University of Washington)
Co-PI(s): Carr, Robert (UW) : Michel-Hart, Nick (UW) : Snyder, Avery (UW) : Sanford, Thomas (UW) : Girton, James (UW) : D’Asaro, Eric (UW)
Start Year: 2020 | Duration: 3 years
Partners: University of Washington, Teledyne Webb Research

Project Abstract:

This project will develop a next generation profiling float that measures horizontal velocity and mixing, called the ElectroMagnetic Velocity Profiler (EMVP). This design will provide a long-duration, low-cost, and highly adaptable instrument that is well suited for use in distributed arrays at the local to global scale. Improvements in internal components will yield a float able to do onboard autonomy (adaptive sampling or mission modification) and high-level processing, which will open up new operational capabilities for scientific and applied applications.

At the moment, there is no commercial instrument available that meets these sampling needs. An old design that measures oceanic electric fields to obtain velocity is now obsolete because its main microprocessor stopped being manufactured, and it was increasingly limited by its use of twenty year old technology. Improvements in microprocessor power, computing efficiency, memory and storage capacity, and more serial inputs will create a much more capable float that will enable large range of future uses. The electronics will be optimized for low noise electrical and turbulence measures for the first time. The float firmware will be designed from scratch to simplify command and control, to provide hooks for adaptive mission control, and to enable rapid benchtop testing of float control logic. The high computing power improves data quality by permitting full onboard processing and data reduction (e.g. for turbulence) prior to satellite transmission. Testing will be performed from the first build stages until field trials, to ensure accurate measurements and robust control.

There is a high scientific need for autonomous and long duration measurements of subsurface velocity. The old float has been used extensively at APL to sample internal waves, mixing processes, input of wind energy into the ocean, underneath sea ice, and the fundamental velocity field. A growing number of external users have studied the ocean response to hurricanes, basic geo-physical fluid dynamics, and naval applications for environmental sampling. Such advances will end and outside use will die if these unique sampling capabilities are not regained. We take this opportunity to make a more accurate, capable and extensible design to support future applications.

The outcome of our effort will be an electronics design and mission firmware that can be commercialized and sold through Teledyne Webb Research. This will make our work available to other researchers who have used velocity profiling floats in the past. In addition, this project will transition knowledge to build electromagnetic sensors from a highly successful group of scientists and engineers to a new generation of researchers.