“Who Is John Galt?” Finally Answered

November 22, 2015 by Bryan Cockfield 107 Comments

For those who haven’t read [Ayn Rand’s] philosophical tome Atlas Shrugged, there’s a pretty cool piece of engineering stuffed in between the 100-page-long monologues. Although fictional, a character manages to harness atmospheric static electricity and convert it into kinetic energy and (spoilers!) revolutionize the world. Harnessing atmospheric static electricity isn’t just something for fanciful works of fiction, though. It’s a real-world phenomenon and it’s actually possible to build this motor.

As [Richard Feynman] showed, there is an exploitable electrical potential gradient in the atmosphere. By suspending a tall wire in the air, it is possible to obtain voltages in the tens of thousands of volts. In this particular demonstration, a hexacopter is used to suspend a wire with a set of needles on the end. The needles help facilitate the flow of electrons into the atmosphere, driving a current that spins the corona motor at the bottom of the wire.

There’s not much torque or power generated, but the proof of concept is very interesting to see. Of course, the higher you can go the more voltage is available to you, so maybe future devices such as this could exploit atmospheric electricity to go beyond a demonstration and do useful work. We’ve actually featured the motor that was used in this demonstration before, though, so if you’re curious as to how a corona motor works you should head over there.

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Laser-cut Cardboard Planetary Gearset Is Pretty, But Useless

November 22, 2015 by Elliot Williams 11 Comments

[Shane] made a project that speaks directly to our heart — combining laser cutting, cardboard, and gears. How could it be any better? Well, it could do anything. But that’s quibbling. It’s fun enough just to watch the laser-cut cardboard planetary gears turn. (Video after the break.)

It was made on a laser cutter using the gear extensions for generating gears in Inkscape, everybody’s favorite free SVG editor.

In his writeup, [Shane] touches on all of the relevant details: all of the gear pitches need to be the same, and the number of teeth in the sun gear (in the center) needs to equal the number of teeth in the ring (outside) divided by the number of planets (orbiting, in the middle). So far so good.

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The Easiest Infinity Mirror Build

November 21, 2015 by James Hobson 28 Comments

Infinity mirrors are awesome. They’re great conversation pieces, and even more fun to stare into forever and ever and ever and ever… They can be tricky to build, but there’s actually a really easy way to do it, and [William] shows us how.

The way a infinity mirror works is it uses a one-way mirror with lights around the perimeter in front of a regular mirror. The majority of the light gets bounced back and forth between the two mirrored surfaces, and because you can see into the one-way mirror, you get that really cool infinity effect.

Now if you went out and bought a one way mirror, built the frame, and put it all together — it’d be a lot of work. But there’s an easier way to do it on the cheap. Mirrored car tint foil. Although it’s illegal on your car in most states, it’s still pretty easy to find. Continue reading “The Easiest Infinity Mirror Build” →

Physical Fitness For The Truly Lazy

November 21, 2015 by Al Williams 15 Comments

We’re going to get in shape around here, starting today. Well… in the United States, it is almost Thanksgiving, so we might as well wait until… but then it is going to be the end of the year and between Christmas, Hanukkah, and New Year’s, we should put it off until then.

OK, we get it. There’s always some excuse. We know we should go on and do some push ups today. Of course, we are a lazy bunch, so not everyone’s going to do a full push up. Then we’ll all argue how many we actually did. If this sounds like you, maybe you need an Arduino-based project that counts proper push ups.

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FleaFPGA + Arduino Uno = FleaFPGAUno

November 21, 2015 by Richard Baguley 95 Comments

Some things are better together: me and my wife, peanut butter and jelly, and FPGAs and Arduino Unos. Veteran hacker [Valentin Angelovski] seems to agree: the FleaFPGA Uno is his latest creation that combines an FPGA (a Lattice MachX02 700HC) with an Arduino-compatible CPU.

It’s a step-up model from the origional FleaFPGA. With a few other components thrown in (such as a HDMI and composite video output and a WiFi option), you have a killer combination for experimenting with FPGAs or building an embedded system. That is because the Arduino part frees the FleaFPGA Uno from the breadboard: you can easily program, control and interface with the FPGA over a serial line or a wireless link using the Arduino IDE. There is even support for Arduino shields (albeit only 3.3V ones), making it even more expandable. This would be an awesome starting point for a retro gaming system, as many 8-bit consoles can be easily emulated in an FPGA. [Valentin] is currently selling the boards directly, and they are very reasonably priced at $50 or $60 for the WiFi version.

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DOE Announces A High Performance Computing Fortran Compiler Agreement

November 21, 2015 by Rud Merriam 21 Comments

The U.S. Department of Energy’s National Nuclear Security Administration (NNSA) and its three national labs this week announced they have reached an agreement for an open-source Fortran front-end for Higher Performance Computing (HPC). The agreement is with IBM? Microsoft? Google? Nope, the agreement is with NVIDIA, a company known for making graphics cards for gamers.

The heart of a graphics card is the graphics processor unit (GPU) which is an extremely powerful computing engine. It’s actually got more raw horsepower than the computer CPU, although not as much as many claim. A number of years ago NVIDIA branched into providing compiler toolsets for their GPUs. The obvious goal is to drive sales. NVIDIA will use as a starting point their existing Fortran compiler and integrate it with the existing LLVM compiler infrastructure. That Fortran, it just keeps chugging along.

You can try out GPU programming on your Raspberry Pi. Yup! Even it has one, a Broadcom. Just follow the directions from Raspberry Pi Playground. You’re going to get your hands dirty with assembly language so this is not for the faint hearted. One of the big challenges with GPUs is exchanging data with them which gets into DMA processing. You could also take a look at [Pete Warden’s] work on using the Pi’s GPU.

Still wondering about the performance of CPU vs GPU? Here’s Adam Savage taking a look…

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Building A Better 3D Printed Gun

November 21, 2015 by Brian Benchoff 149 Comments

Back in 2013, [Cody Wilson] of Defense Distributed designed and built the world’s first completely 3D printed pistol. He called his gun the Liberator, after a World War II-era single-shot pistol designed to be cheap and easy to manufacture, easy to conceal, and for members of the French Resistance, ‘a great gun to obtain a better gun’.

[Cody]’s Liberator turned out to be a great gun to obtain two or three fewer fingers. Not only was this a single-shot pistol, it was a single barrel pistol; with each round fired requiring a new 3D printed barrel. Tests were carried out, explosions happened, and we couldn’t even get the thing to print. For all the media hubbub, for all the concerned legislators, the first 3D printed pistol was much ado about nothing.

3D printers are still an extremely interesting technology, and if history has proved one thing, it’s that engineers and tinkerers will keep building guns. Last week, [James Patrick] released his latest design for a working 3D printed gun. It still fires the .22lr of the Liberator, but this is a double action revolver, it won’t blow up, and if you drop it, it won’t discharge. It’s the little things that count.

[James]’ revolver is either a 6 or 8-shot revolver uses a pepper-box design, where the gun has multiple chambers and barrels in one gigantic cylinder. The double action design first rotates the cylinder to the next chamber, pulls back a striker loaded up with a firing pin nail, and (hopefully) fires a round. In the video below, [James] goes over the design of his action, and ends up showing off a few test firings of his newly designed gun.

What’s very interesting about this build is how closely the development of 3D printed firearms is following the development of historical firearms. First, we had guns that probably shouldn’t be fired, ever. Now, the technology for 3D printed guns is about up to 1830 or thereabouts. Give it a few more years and we’ll be up to 1911.

Disclaimer: if you live in the US and think this sort of thing should be illegal, contact your state representative and tell them you support a constitutional convention to remove the personal right to own and operate firearms. This right has been upheld many, many times by the judiciary, and a constitutional convention is the only way your wishes could be carried out. Your state representative probably doesn’t read Hackaday; there is no need to comment here. Let’s talk about engineering and technology instead.

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