Researchers at the National Oceanic and Atmospheric Administration's (NOAA) - National Marine Fisheries Service (NMFS) working off the coast of Alaska, utilizes Machine Vision components to map underwater marine wildlife populations. Traditional assessment is done with a net and codend where the fish are caught and brought aboard for species, length, and sex identification. This new "non-lethal fish sampling device" uses stereo optical sampling to obtain these characteristics, preventing the accidental destructive sampling of thousands of fish per year. The "Cam-Trawl" camera system sits at the end of a trawl net that has the codend removed. The net simply herds the fish past the camera where they are imaged and then free to swim about their way through the other end.
Underwater rig with stereo optical camera system, DC to DC converter, and six ODS75 OverDrive Brick Lights from SVL.
The rig is equipped with six ODS75 OverDrive LED strobe lights from Smart Vision Lights. A wide-input-range direct current(DC)-to-DC converter was added to the strobe assembly to allow the strobes to operate using a range of battery configurations from nine to 36 volts DC. The ODS75 strobes were not designed for deep underwater use, so they were placed in individual aluminum housings and encapsulated in epoxy. The DC-to-DC converter and back of the ODS75 strobe circuit board were encapsulated in thermally conductive epoxy to provide a path for heat dissipation, while the rest of the light was potted in clear epoxy.
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Sea Technology - Cam Trawl