Submarine / Rov Robot Ideas?

There are lots of Diy designs from pvc pipe if you want to go the easy route.

https://www.homebuiltrovs.com/mule.html

They are fairly common projects. Just remember radio control has limited range to around 30 feet of water in distance or depth but longer ranges with more reliable control can be done with a tether. The tether is also the cheapest route.

The best Rov projects have a balast system that pumps water in or out of a empty tank which controls buoyancy.

Nice finds Josh.