PAROV-1 - PVC Arduino ROV project

[87TurboIroc]

So I just named it while typing the subject! I officially started the build today with the purchase of $150 worth of SCH-40 PVC pipe. I originally wanted to do SCH-80 but my working depth will only be 25 to 100 feet. Also SCH-80 is expensive and hard to find locally. The 4 inch pipe has a working pressure rating of 220 PSI. Since that is a positive pressure rating and our purposes are effectively a negative pressure, I am using 50% of the rated pressure as the max safe working pressure. So 110 psi or over 240 feet. The most I see myself in would be 150 feet and that is unlikely.

This started as a simple design and grew into a larger design as reality set in. Now I'm looking a full on five thruster (4 lateral, 1 vertical) setup, although I might build it initially as a three thrust config with wiring in place to go to a five. I'm still debating on brushless vs bilge for the thrusters, but brushless is looking better and better cost wise.

The plan is to use on-board power along with a thin tether (fiber pair only), onboard fiber to copper converter, USB over IP adapter and a USB hub. Adding an ethernet switch would allow use of IP CCTV camera with PTZ, and I plan to run a cat5 into the camera housing for this purpose alongside the USB wire. Initially I will likely use a USB web camera, but if I ended up using the 100 Mbps fiber converters, I'm not sure the bandwidth will be good enough. CCTV IP cameras have H.264 compression and would work very well over that bandwidth. The cost to go to 1000Mbps fiber converters is about $120 total. Then USB 2.0 bandwidth is maintained.

Control will be handled by an Arduino Mega connected to a laptop/joystick combo via USB over IP. A second Arduino will handle telemetry data which could be fed via USB or Ethernet to the laptop.

Here is the concept, from which I have now removed the lighting built in to the main 4 inch tubes and will mount it as a separate module to allow for easier modification and adjustment:



And here is the actual build that I started on today!

[reservoirking]

Very nice cant wait to see it finished

[sthone]

Very cool, the thruster placement will make it very maneuverable.

Also keeping an eye on this one...

-Steve

[87TurboIroc]

Funding is a bit short on this for the moment. Also I wanted to do some thruster testing so I have decided to make a very simple three thruster ROV based on my Color Sharp underwater camera. It only has a 20 meter cable so this worked out perfect to make a simple Cat 5 cable to send the voltage directly to each thruster. I'll make a separate thread with details on that.

One thing I've quickly discovered is that I'm going to need some significant thrusters for this PAROV-1 design. There is just a lot of mass and I'm worried that power consumption is going to be higher than I planned. This means more money in batteries! Sending 400VAC down is starting to look more tempting than a thin tether design, but going to a thick tether means less onboard equipment and we're back to a smaller ROV. Or I could just quit complaining and spend an extra $200 on batteries...