John Griffiths and Alicia Dunn presented on underwater drones on Friday 5 July 2024. For their powerpoint presentation, click here. For a narrative explanation, click here.

 

For a video of their equipment, click on this photo:

 

The photo is of John Griffiths-designed X-Calibre 8 thrusters, from 300m to 600m depth capable, multiple interchangeable tool options, with sensors, instruments and artificial intelligence for roles as diverse as search and rescue, control of marine invasive species to ship hull anomaly and bio-fouling detection.

 

This is John Griffiths’s De Litter Bug 8 thrusters, 40m- 200m for marine debris collection and other tasks.  This ROV is aimed mostly at retrieving items such as abandoned fishing gear through to car bodies or sunken boats.  The grappling hook detaches and has a 200 kg breaking strain line 50 metres long with a float on its arm so that items can be hauled in without the ROV being further involved. The ROV also has a quickly demountable twin disc cutter with counter-rotating blades capable of cutting up to 10mm of wire cable. It has a sonar and DVL650 for holding position in currents up to 6 knots. The design is as simple as possible to keep the machining cost down. The idea for this was to help organisations involved in marine debris collection to have the cheapest units possible.

 

 

This photo shows a speargun mounted on an underwater drone for sustainable and selective fishing without the by-catch. Also used when weather conditions make it impossible to launch a boat and can be used off jetties, beaches and headlands.