A truly fine project. Probably the most impressive I’ve seen from an ID student, graduate, in several years.
In a planet of ID students and graduates consumed by Apple this and that, it is inspirational to see real problem solving well explained.
From a design critique only, probably toughness is a problem. I imagine daily use in trawler ships is extremely, grotesquely abusive. Also the power source issue seems guaranteed for problems; perhaps other power source such as electrochemical, chemiluminescent?. Probably also, in fishery industry, acceptance of the new is difficult, and tolerance for failure is zero, rejection absolute. Could there be different ring models for different specific fish species avoidance?
Please keep us informed how your project goes.