Hackaday Prize Entry: Dave Thomas’ Desert Dryer

It seemed utter madness — people living in hot desert climates paying to heat air. At least it seemed that way to [David Thomas] before he modified his tumble dryer to take advantage of Arizona’s arid environment.

Hanging the wash out to dry is a time-honored solution, and should be a no-brainer in the desert. But hanging the wash takes a lot of human effort, your laundry comes back stiff, and if there’s a risk of dust storms ruining your laundry, we can see why people run the dryer indoors. But there’s no reason to waste further energy heating up your air-conditioned interior air when hot air is plentiful just a few meters away.

[David]’s modification includes removing the gas heating components of the dryer and adding an in-line filter. He explains it all in a series of videos, which at least for his model, leave no screw unturned. It’s not an expensive modification either, consisting mostly of rigid dryer hose and copious amounts of aluminum duct tape. He mentions the small fire that resulted from failing to remove the gas igniter, so consider yourself warned. The intake filter and box were originally intended for a house air-conditioning system, and required only minimal modifications.

This is a great build, being both cheap and easy to implement as well as being environmentally friendly without requiring a drastic change to [David]’s lifestyle. It makes us wish we had a similar endless supply of hot air.

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Robot Moth Is Learning to Fly Like A Real Moth

Harvard University has had the flying robot insect market covered for a long time. However, their robot bee, while cool, was starting to bum them out. They wanted to put the battery and brain on the robocritter and have it fly around without a tether. Technology just wasn’t moving fast enough for them, so they’ve picked a different bug, this time a moth.

The Wyss Institute for Biologically Inspired Engineering at Harvard University is known for its Flying Winged Micro Air Vehicles or FWMAV. Which is a pretty good example of what happens when you let engineers name things. This FWMAV, weighs in at a hefty 3grams and has a 16mm wingspan. It also has propulsion, sensors, communication, brains, and power on board. Pretty impressive, the heaviest item is the motor!

The moth can produce 4g of thrust, and they’ve shown it capable of staying aloft once launched with a small catapult. Since they’ve proven that it can at least fly, the next steps are to figure out the dynamics of moth-based flight. Right now it stays pointed in the right direction with a very tiny tail fin like on an airplane. Real moths manage this feat with independent wing control, which the robot doesn’t have yet.

It will be a while before a we’ll see robot moths bumping into our computer monitors a night, stealing our passwords, but it’s a really cool exercise in robot miniaturization.

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Hackaday Links: June 5, 2016

CERN is having a hackathon. It’s in October, yes, but the registration is closing on the 15th of June. They’ve been doing this every year, and the projects that come out of this hackathon are as diverse as infrastructure-less navigation, cosmic ray detectors, and inflatable refrigerators.

Have one of those solder fume extractors? Here’s an obvious improvement. [polyglot] put a strip of LEDs around the frame of his solder fume extractor to put a little more light on the subject.

A few months ago, [Bunnie] started work on a book. It was the Essential Guide to Electronics in Shenzhen. It’s made for hardware hackers to figure out how to buy stuff in Shenzhen, using a neat point-and-understand interface. Those books are now being shipped to people around the globe. I got one, and here’s the mini-review: it’s awesome. Is it a complete travel guide? No, but if you dropped me off at Hong Kong International, I could probably 1) Make it to Shenzhen 2) Buy random LEDs 3) Find a hotel 4) Get a beer 5) Not die. Pics below.

You’re hackers, and that means you’re the people who build stuff for all those ‘makers’ out there. Don’t have an MBA? No problem, [Dave Jones] has your back. He re-did his Economics of Selling Hardware video from several years ago. It’s 25 minutes long, and gives you enough information so you’re not a complete idiot at the business end of design.

Like Raspberry Pis stuffed into things? Here’s a Pi Zero stuffed into a MegaDrive cartridge. Now someone grab a Sonic and Knuckles cart, build a ROM reader, and do a proper cart-reading emulator.

If you’re into R/C, you know about Flite Test. They’re the folks that make crazy, crazy model planes out of Dollar Tree foam board, and have gotten hundreds of people into the hobby. Flite Test is having their own con, Flight Fest, in a little over a month. It’s in Ohio, and from last year’s coverage of the event, it looks like a really cool time.

So, No Man’s Sky is coming out soon. It’s a space game set in a procedurally generated, infinite galaxy. Does anyone have any idea on how to form a Hackaday clan? Somebody should start a Hackaday clan/alliance/thing. I’ll meet you guys at the core.

A Cake Tin Makes A Great Tube Amp Chassis

If you have ever had a go at building a tube-based project you will probably be familiar with the amount of metalwork required to provide support structures for the tubes themselves and the various heavy transformers and large electrolytic capacitors. Electronic construction sixty years ago was as much about building the chassis of a project as it was about building the project itself, and it was thus not uncommon to see creative re-use of a chassis salvaged from another piece of equipment.

This morning we stumbled upon a rather nice solution to some of the metalwork woes facing the tube constructor courtesy of [Bruce], who built his tube audio amplifier on a chassis made from a cake tin and with its transformers housed in decorative display tins.

The circuit itself is a straightforward single-ended design using an ECL82 triode-pentode on each stereo channel, and comes courtesy of [Nitin William]. The power supply is on-board, and uses a pair of silicon diodes rather than another tube as the rectifier.

It’s true that [Bruce] has not entirely escaped metalwork, he’s still had to create the holes for his tubes and various mountings for other components. But a lot of the hard work in making a tube chassis is taken care of with the cake tin design, and the result looks rather professional.

We have something of a personal interest in single-ended tube amplifiers here at Hackaday, as more than one of us have one in our constructional past, present, or immediate futures. They are a great way to dip your toe in the water of tube amplifier design, being fairly simple and easy to make without breaking the bank. We’ve certainly featured our share of tube projects here over the years, for example our “Groove tube” round-up, or our look at some alternative audio amplifiers.

CNC Drag Knife Upgrade with Off-the-Shelf Blades

Drag Knives seem to be the overshadowed awkward kid on the playground of CNC equipment, but they have a definitive niche making stencils, vinyl stickers, and paper cuts. Unfortunately, the drag knife blades for CNC routers are pricey — over $100 for a single blade. [Brian] at the Grunblau Design Studio took the price point as a challenge to build his own end-effector. A few iterations later, he’s created his very own drag knife blade tool that accepts replaceable steel blades for cutting.

From constraint-driven concept, to a 3D printed proof-of-concept, to a fully machined aluminum prototype, [Brian’s] efforts hit all the highlights of a well-engineered project. At the end of the day, dull blades can be swapped for a few dollars, rather than shelling out another $150 for the off-the-shelf variant. We’ve seen bootstrapped CNC vinyl cutters before, but nothing that takes an original re-envisioning of the tool itself.

In Soviet Russia, DIY Laser Rangefinder Scan YOU!!

Yakov Smirnoff used to say, “In America, you can always find a party. In Soviet Russia, Party finds YOU!!” Only here, it’s a laser rangefinder.

In this project (automatic translation), [iliasam] makes his own scanning laser rangefinder, like the ones that we’ve seen in fancy vacuum cleaners. But he does it from scratch.

b91e3927436e885627e52179a5ed6c70While this sort of thing is easy if you have a webcam and a ton of processing power to throw at it, [iliasam] takes the hard way out — measuring the parallax of the reflected spot through a lens on a linear image sensor (which renders as “photodetector line” in translated Russian).

Linear image sensors are a lot like the elements in your CMOS digital camera, with the exception that the elements are arranged in a line instead of a plane, and they’re a lot easier to interface with a microcontroller. Hold a data line high to take an exposure, and then clock out the (analog) voltage values that correspond to the amount of light that hit each cell in the line array. While [iliasam] paid an estimated $18 for his, we’ve found them much cheaper on eBay. And there’s usually a linear sensor, often RGB and complete with driver circuitry, in a scanner if you take one apart. This could be done for just a few bucks if you were thrifty.

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How An Amiga Graphics Business Ran In The 1990s

If you have ever used an eraser to correct a piece of pencil work, have you ever considered how much of an innovation it must have seemed when the first erasers were invented? It might seem odd to consider a centuries-old piece of stationery here on Hackaday, but there is a parallel in our own time. Digital image manipulation is such a part of everyday life these days as to have become run-of-the-mill for anyone with a mobile phone and the right app, but it’s easy to forget how recent an innovation it really is. Only a few decades ago your only chance of manipulating a photograph was to spend a lot of time in a darkroom with a photographic developer of exceptional skill, now children who have never known a world in which it wasn’t possible can manipulate their selfies with a few deft touches of the screen.

[Steve Greenfield] pointed us at a detailed description of the business he ran in the 1990s, offering digital and composite photography using an upgraded Amiga 3000.  It caught our attention as a snapshot of the state of digital image manipulation when these things still lay at the bleeding edge of what was possible.

His 3000 was highly customised from the stock machine. It featured a Phase 5 68060 accelerator board, a Cybervision 64 graphics card, a then-unimaginably-huge 128MB RAM, and an array of gigabyte-plus Fast SCSI drives.  To that he had attached a Polaroid SCSI digital camera with a then-impressive 800×600 pixel resolution. The Polaroid had no Amiga drivers, so he ran the Shapeshifter Mac emulator to capture images under the MacOS of the day. The fastest 68000-series Mac only had a 68040 which the early PowerPC Macs could only emulate, so he writes that his 68060-equipped Amiga ran the Mac software faster than any Mac at the time.

His stock-in-trade was attending sci-fi conventions and giving costumed attendees pictures with custom backgrounds, something of a doddle on such a souped-up Amiga. He writes of the shock of some Microsoft employees on discovering a 60MHz computer could run rings round their several-hundred-MHz Pentiums running Windows 95.

His business is long gone, but its website remains as a time capsule of the state of digital imagery two decades ago. The sample images are very much of their time, but for those used to today’s slicker presentation it’s worth remembering that all of this was very new indeed.

In a world dominated by a monoculture of Intel based desktop computers it’s interesting to look back to a time when there was a genuine array of choices and some of them could really compete. As a consumer at the start of the 1990s you could buy a PC or a Mac, but Commodore’s Amiga, Atari’s ST, and (if you were British) Acorn’s ARM-based Archimedes all offered alternatives with similar performance and their own special abilities. Each of those machines still has its diehard enthusiasts who will fill you in with a lengthy tale of what-if stories of greatness denied, but maybe such casualties are best viewed as an essential part of the evolutionary process. Perhaps the famous Amiga easter egg says it best, “We made Amiga …

Here at Hackaday we’ve covered quite a few Amiga topics over the years, including another look at the Amiga graphics world. It’s still a scene inspiring hardware hackers, for example with this FPGA-based Amiga GPU.

Amiga 3000 image: By [Joe Smith] [Public domain], via Wikimedia Commons.