Extreme Waterproof 3D Prints

February 18, 2024 by Al Williams 21 Comments

Since the crew at [CPSdrone] likes to build underwater drones — submarines, in other words — they need to 3D print waterproof hulls. At first, they thought there were several reasons for water entering the hulls, but the real reason was that water tends to soak through the print surface. They’ve worked it all out in the video below.

Since the printer is an FDM printer, it isn’t surprising that the surface has tiny pores; even the tiniest pores will let water in at high pressure. They tried using epoxy to seal the prints, which worked to some degree. They did tests using an example submersible hull that you can try yourself if you like.

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Flying Submarine Documentary Is A Story Of Defied Assumptions

June 25, 2023 by Donald Papp 39 Comments

Donald Reid had a passion for applying himself to challenging problems, and in many ways his life’s work was that of developing a prototype submersible aircraft — or flying submarine — for which his son Bruce was a test pilot. [Jesse Moody] brought to our attention a fantastic documentary he created (with a short teaser trailer here) in which he interviews Bruce, and in the process teaches us all about a story that spanned decades and formed an important part of aviation history. Bruce experienced his share of hair-raising moments while testing the craft, but still has all of his fingers and limbs. Still, in his own words, “you wouldn’t be doing that kind of testing today!”

In many ways, the story revolves around defying assumptions. Without context, a “flying submarine” project might sound like a lone kook’s obsession, but Donald Reid was nothing of the sort. He was a brilliant engineer who was able solve problems by applying his skill and intellect with a laser-like focus. And it turns out that getting a submerged vehicle to successfully transition from waterbound craft to airborne is a source of numerous and novel problems that were not trivial to solve. In fact, these problems needed to be solved in order to develop the Tomahawk cruise missile, which is launched by submarine. And that brings us to the lawsuit that bookended it all.

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We All Live In A PVC Submarine

December 11, 2021 by Al Williams 11 Comments

We doubt you could really live in [Pena’s] PVC submarine, but now the song’s stuck in our head anyway. Although the post is in Portuguese, you can get a pretty good idea of how it works, and translation software is better than ever. Transcending the language barrier, there are videos of just about every step of the construction. We didn’t, however, find a video of the vehicle in the water.

The plumber’s delight has modified motors for thrusters, and a camera as well. Epoxy potting keeps things waterproof. We’ve seen candle wax used for the same purpose in other builds.

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Build Your Own Submarine

December 10, 2021 by Al Williams 22 Comments

If you are tried of building things that fly, why not try a submarine like [DIYPerks] did? As you can see in the video below, the key is to control buoyancy, and the mechanism used is impressive. The sub has two giant syringes fore and aft to compress or decompress water. The plungers are now 3D-printed actuators that travel on a lead screw. Two high-torque motors and some batteries sandwiched in acrylic disks make up the rest. This is a big vessel — you won’t be trying this in your bathtub and maybe not even your pool unless it is a big one.

Of course, everything needs to be watertight. Instead of trying to waterproof a power switch, this sub uses a reed switch so that a nearby magnet can turn it on. Not an original idea, but we always think it is more elegant than seals and potting compounds.

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A Thousand Feet Under The Sea

December 11, 2020 by Al Williams 15 Comments

If you were to plumb the depth of the oceans, you could only get so far with a snorkel or a SCUBA tank. We don’t know the price, but if you have enough money, you might consider the Triton 3300/6 — a six-person submersible that can go down to 3,300 feet (hence the name–get it–3300/6). Billed as “diving for the entire family,” we aren’t sure we can load grandma and the kids in something like this, but that doesn’t mean we wouldn’t like to try.

The machine can carry up to 1,760 pounds and can make 3 knots which isn’t going to set any speed records. At around 24,000 pounds, the two main thrusters are lucky to make that speed. The view bubble is apparently optically perfect acrylic made by a German company and the company claims the 100-inch diameter bubble is the world’s largest spherical acrylic pressure hull.

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Aruna: An Open Source ROV For Affordable Research

October 7, 2020 by Tom Nardi 19 Comments

Underwater exploration and research can be exceedingly dangerous, which is why remotely operated vehicles (ROVs) are so commonly used. Operators can remotely command these small submersibles to capture images or collect samples at depths which would otherwise be unreachable. Unfortunately, such technology comes at a considerable price.

Believing that the high cost of commercial ROVs is a hindrance to aquatic conservation efforts, [Noeël Moeskops] has been developing an open source modular ROV he calls Aruna. Constructed largely from off-the-shelf components and 3D-printed parts, the Aruna promises to be far more affordable than anything currently on the market. Hopefully cheap enough to allow local governments and even citizens to conduct their own underwater research and observations.

More than just the ROV itself, Aruna represents an entire system for developing modular underwater vehicles. Whether you decide to build the boilerplate ROV documented and tested by [Noeël], or implement individual components into your own design, the project is a valuable source of hardware and software information for anyone interested in DIY underwater robotics.

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Analyzing Water Quality With A Pair Of Robots

August 14, 2020 by Tom Nardi 2 Comments

To adequately study a body of water such as a lake, readings and samples need to be taken from an array of depths and locations. Traditionally this is done by a few researchers on a small boat with an assortment of tools that can be lowered to the desired depth, which is naturally a very slow and expensive process. As the demand for ever more granular water quality analysis has grown, various robotic approaches have been suggested to help automate the process.

A group of students from Northeastern University in Boston have been working on Project Albatross, a unique combination of semi-autonomous vehicles that work together to provide nearly instantaneous data from above and below the water’s surface. By utilizing open source software and off-the-shelf components, their system promises to be affordable enough even for citizen scientists conducting their own environmental research.

The surface vehicle, assembled from five gallon buckets and aluminum extrusion, uses a Pixhawk autopilot module to control a set of modified bilge pumps acting as thrusters. With ArduPilot, the team is able to command the vehicle to follow pre-planned routes or hold itself in one position as needed. Towed behind this craft is a sensor laden submersible inspired by the Open-Source Underwater Glider (OSUG) that won the 2017 Hackaday Prize.

Using an array of syringes operated by a NEMA 23 stepper motor, the glider is able to control its depth in the water by adjusting its buoyancy. The aluminum “wings” on the side of the PVC pipe body prevent the vehicle from rolling will moving through the water. As with the surface vehicle, many of the glider components were sourced from the hardware store to reduce its overall cost to build and maintain.

The tether from the surface vehicle provides power for the submersible, greatly increasing the amount of time it can spend underwater compared to internal batteries. It also allows readings from sensors in the tail of the glider to be transmitted to researchers in real-time rather than having to wait for it to surface. While the team says there’s still work to be done on the PID tuning which will give the glider more finely-grained control over its depth, the results from a recent test run already look very promising.