This may sound crazy. How about a quadcopter designed for underwater use. Brushless motors operate perfectly well submerged and the rest can be waterproofed quite easily. Idea being that one would use small props, basically the quad would operate in a different medium but essentially it should still stabilise as it does in air. I thought about escs (which don't like water) getting hot but they could be exposed, covered with tectyl or some other waterproofing spray.
As a fail-safe, waterquad would be slightly buoyant so in case of power loss, it would merely float to the surface. One would then have keep throttle on all the time to stay submerged and power up to sink as opposed to normal operation. I know that 2.4ghz does not work underwater but the older 35mhz systems do. For fpv, 1.3ghz could be used ?? Also I wonder which flight controller would work best, kk2 maybe for cost-effectiveness.
Has this been attempted before and if so, any success? Couldn't seem to find anything on this concept. I'm itching to start building but somebody please stop me if I'm wasting my time.
Do you plan to have some sort of self navigation whilst underwater ? Using ultrasonic s or something to do a sort of underwater location system. I guess one of the problems I face (maybe you don't ) is where ever I want to use my underwater ROV I lose visibility from the surface pretty much straight away. I did contemplate a a completely autonomous ROV with a crude map built in and echo location. ' using a repeater buoy at the moment with fiber optic connected to the ROV but this makes it so cumbersome for when its in flight. How are you steering yours? The acoustics (as you say) can send video but it is so slow it's not really any help for navigation purposes. I also dabbled with Q codes and getting the ROV to recognise these in certain locations and try and use these to navigate...
So once again you've done and excellent job and it looks (and works) a hell of a lot better than any of mine, however if you crack the high speed coms problem your name would be in lights...
I hear you. This will only really be of great interest with FPV video. We have been researching for a while on ways to do high speed communications underwater with no great solution.
For now, we are adding a sonar and have the vehicle do pre-defined maneuvers (e.g., go down to certain depth, do 360, come back up)..... not that exciting yet.
Googling "underwater wifi" comes up with some research projects, but they involve large buoys and are still in the development stages.
Interesting, I have been working on an underwater quadcopter myself. Message me if you would like to talk further.
Anything is possible, don't give up. Nothing in the world of technology is a waste of time.
I am working on this exact project for a few months. I attached the proof of concept design without the electronics tube up front. I build 4 70mm ducted fan units with outrunner motors. The back open section is for the main drive Jet Pump motor running a 70mm fan, in a jet drive unit. Going to run the ArduPlane 3.6.0 quad plane setup. Custom programmed the ESC units with reverse for a mid-point on the controls. Will be running some batteries on board, and they supply the primary power to everything, but power is also being sent down the Ethernet cable Via a Hybrid POE system, which is enough power to run all electronics, lights, and small amount of motor function, but all access power will be sent to the batteries as a charge.
Probably 3-4 weeks from my first test, If I can get the BBBmini board up and running.