We often think of submarines as fairly complex pieces of machinery, and for good reason. Keeping the electronics watertight can naturally be quite difficult, and maintaining neutral buoyancy while traveling underwater is a considerable engineering challenge. But it turns out that if you’re willing to skip out on those fairly key elements of submarine design, the whole thing suddenly becomes a lot easier. Big surprise, right?
That’s precisely how [Peter Sripol] approached his latest project, which he’s claiming is the world’s smallest remote control submarine. We’re not qualified to say if that’s true or not, but we were certainly interested in seeing how he built the diminutive submersible. Thanks to the fact that it started life as one of those cheap infrared helicopters, it’s actually a fairly approachable project if you’re looking to make one yourself.
After testing that the IR communication would actually work as expected underwater, [Peter] liberated the motors and electronics from the helicopter. The motor’s wires were shortened, and the receiver PCB got a slathering of epoxy to try and keep the worst of the water out, but otherwise they were unmodified.
If you’re wondering how the ballast system works, there isn’t one. The 3D printed body angles the motors slightly downwards, so when the submarine is moving forward it’s also being pulled deeper into the water. There aren’t any control surfaces either, differential thrust between the two motors is used to turn left and right. This doesn’t make for a particularly nimble craft, but in the video after the break it certainly looks like they’re having fun with it.
Looking for a slightly more complex 3D printed submersible vehicle? Don’t worry, we’ve got you covered.