Get Compressed Air From Falling Water With The Trompe

If you’re like us, understanding the processes and methods of the early Industrial Revolution involved some hand waving. Take the blast furnace, which relies on a steady supply of compressed air to stoke the fire and supply the oxygen needed to smelt iron from ore. How exactly was air compressed before electricity? We assumed it would have been from a set of bellows powered by a water wheel, and of course that method was used, but it turns out there’s another way to get compressed air from water: the trompe.

AsĀ [Grady] from Practical Engineering explains in the short video below, the trompe was a clever device used to create a steady supply of high-pressure compressed air. To demonstrate the process, he breaks out his seemingly inexhaustible supply of clear acrylic piping to build a small trompe. The idea is to use water falling around a series of tubes to create a partial vacuum and entrain air bubbles. The bubbles are pulled down a vertical tube by the turbulence of the water, and then enter a horizontal section where the flow evens out. The bubbles rise to the top of the horizontal tube where they are tapped off by another vertical tube, as the degassed water continues into a second vertical section, the height of which determines the pressure of the stored air. It’s ingenious, requiring no power and no moving parts, and scales up well – [Grady] relates a story about one trompe that provided compressed air commercially for mines in Canada.

Need an electricity-free way to pump water instead of air? Check out this hydraulic ram pump that takes its power from the water it pumps.

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A Simple Auger Pet Feeder

Pet feeders are a popular maker project. One can speculate that this shows the great self-confidence common to the maker set, who are willing to trust their own work to keep their animal companions alive for many days at a a time. [Darren Tarbard] is one such maker, who put together this simple auger build.

The project consists of a hopper for dry pet food, into which a screw auger is inserted. Both parts are 3D printed, making them easy to produce at home for the average maker. The build was designed specifically around the parts [Darren] had to hand, namely a 28BYJ-48 stepper motor, which is charged with turning the auger. Running the show is an Arduino, which can be run with whatever suitable timing code is necessary to feed the particular pet in question. There’s also a remixed version that adds a larger food storage dish on top for longer periods of unattended operation, created by [szuchid].

It’s a basic build, but one that would be readily achievable by most makers with little more than some junkbox components and a roll of filament. Of course, if your pet prefers wet food, you might need a different design. Video after the break.

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Jen Costillo Explains Why Hackers Thrive In A Recession

If you haven’t noticed, this is an absolutely fantastic time to be a hacker. The components are cheap, the software is usually free, and there’s so much information floating around online about how to pull it all together that even beginners can produce incredible projects their first time out of the gate. It’s no exaggeration to say that we’re seeing projects today which would have been all but impossible for an individual to pull off ten years ago.

But how did we get here, and perhaps more importantly, where are we going next? While we might arguably be in the Golden Age of DIY, creative folks putting together their own hardware and software is certainly nothing new. As for looking ahead, the hacker and maker movement is showing no signs of slowing down. If anything, we’re just getting started. With a wider array of ever more powerful tools at our disposal, the future is very literally whatever we decide it is.

In her talk at the 2019 Hackaday Superconference, The Future is Us: Why the Open Source And Hobbyist Community Drive Consumer Products, Jen Costillo not only presents us with an overview of hacker history thus far, but throws out a few predictions for how the DIY movement will impact the mainstream going forward. It’s always hard to see subtle changes over time, and it’s made even more difficult by the fact that most of us have our noses to the proverbial grindstone most of the time. Her presentation is an excellent way for those of us in the hacking community to take a big step back and look at the paradigm shifts that put such incredible power in the hands of so many.

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Who Invented The Mouse? Are You Sure?

If you ask most people who invented the mouse, they won’t know. Those that do know, will say that Doug Englebart did. In 1964 he had a box with two wheels that worked like a modern mouse as part of his work at Stanford Research Institute. There is a famous demo video from 1968 of him showing off what looks a lot like an old Mcintosh computer. Turns out, two other people may have an earlier claim to a mouse — or, at least, a trackball. So why did you never hear about those?

The UK Mouse

Ralph Benjamin worked for Britain’s Royal Navy, developing radar tracking systems for warships. Right after World War II, Ralph was working on the Comprehensive Display System — a way for ships to monitor attacking aircraft on a grid. They used a “ball tracker.” Unlike Engelbart’s mouse, it used a metallic ball riding on rubber-coated wheels. This is more like a modern non-optical mouse, although the ball tracker had you slide your hand across the ball instead of the other way around. Sort of a trackball arrangement.

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Hackaday Podcast 050: Counterfeit Chips, Servo Kalimba, Resistor Colors, Pi Emulation, And SED Maze Solver

Hackaday editors Elliot Williams and Mike Szczys work their way through a dizzying maze of great hacks this week, bringing you along for the ride.

We take a look at simplifying home automation with Node-RED and marvel at the misuse of the SED — Linux’s stream editor for filtering and transforming text — to find your way through a maze. Have the hippest portable; grab your really old Apple laptop and stuff a not-so-old Apple desktop inside. We bring it on home with our love (or hate?) for the resistor color code.

Take a look at the links below if you want to follow along, and as always tell us what you think about this episode in the comments!

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (60 MB or so.)

Continue reading “Hackaday Podcast 050: Counterfeit Chips, Servo Kalimba, Resistor Colors, Pi Emulation, And SED Maze Solver”

Magic Acrylic Makes This Ring Stand Out

LEDs look great no matter how you use them, but sometimes you want to hide them from direct view. [Charlyn] found a great way to do that, using a special material designed just for the purpose.

[Charlyn] built a ring as a piece of fashion jewelry, hooking up a Gemma M0 microcontroller to a Neopixel Jewel, which packs 7 individual LEDs. The hardware is secreted away inside an enclosure featuring both 3D-printed and lasercut parts.

Rather than openly show off the electronics, it’s all hidden away inside. Instead, a piece of black Chemcast LED acrylic is used, which allows LED light to shine through, while otherwise appearing opaque. Those interested in learning more can check out the product details on the manufacturer site.

It’s a great way to make a subtle costume piece that only reveals its flashier side when you so decide. We’ve seen badges use similar techniques on PCBs to great effect, too. Video after the break.

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This Week In Security: Windows 10 Apocalypse, Paypal Problems, And Cablehaunt

Nicely timed to drop on the final day of Windows 7 support, Windows 10 received a fix to an extremely serious flaw in crypt32.dll. This flaw was reported by the good guys at the NSA. (We know it was the good guys, because they reported it rather than used it to spy on us.) It’s really bad. If you’re running Windows 10, go grab the update now. OK, you’re updated? Good, let’s talk about it now.

The flaw applies to X.509 keys that use elliptic curve cryptography. We’ve discussed ECC in the past, but let’s review. Public key encryption is based on the idea that some calculations are very easy to perform and verify, but extremely difficult to calculate the reverse operation.

The historic calculation is multiplying large primes, as it’s unreasonably difficult to factorize that result by a conventional computer. A true quantum computer with enough qubits will theoretically be able to factorize those numbers much quicker than a classical computer, so the crypto community has been searching for a replacement for years. The elliptic curve is the solution that has become the most popular. An agreed-upon curve and initial vector are all that is needed to perform the ECC calculation.

There are potential weaknesses in ECC. One such weakness is that not all curves are created equal. A well constructed curve results in good cryptography, but there are weak curves that result in breakable encryption.

With that foundation laid, the flaw itself is relatively easy to understand. An X.509 certificate can define its own curve. The Windows 10 implementation doesn’t properly check the curve that is specified. A malicious curve is specified that is similar to the expected curve — similar enough that the checks in crypt32 don’t catch it. Continue reading “This Week In Security: Windows 10 Apocalypse, Paypal Problems, And Cablehaunt”