Hi
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.
Replies
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.
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.
This might be of interest:
https://www.youtube.com/watch?v=U7vl7uqwN4I
Check out our flying+diving quadrotor demo here:
https://www.youtube.com/watch?v=STRijGJ5qtI
Very nice thanks for the link. Please don't take this the wrong way as it's a very nicely built project you've got, However It hasn't cracked the real problem though or at least the video doesn't show it has. To be able to go on the surface (in air) or underwater is relatively easy and a good few people have done it but we haven't (well I haven't) managed to crack how to get a live video feed back from the craft wirelessly and to me that is the technical difficulty to overcome as there's little point having the ROV underwater without it.
You can steer it with ultrasonics over great distances but Video is a few feet....
What communications did you use ? I'm really hoping you tell me video is no problem I will truly be in awe then...
Others have been working on wireless communication underwater for decades. that is not our focus. But there are some acoustic modems that would be capable of low frame rate, low-res real-time video transmission. Our focus with this initial prototype is on autonomous underwater operation with a video camera storing HD video. The video would be wirelessly accessible as soon as the vehicle surfaces.
Others suggested a tether or a repeater buoy.
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...
Hi Bill,
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.
Why keep the camera inside? A go pro in a waterproof case with a signal wire ran into the ROV would solve allot of problems
You wouldn't even need a wire. Bluetooth doesn't go very far under water but would be good enough to go through a plastic hull of a ROV...and have a receiver in side.