Homopolar Motor

November 10, 2009 by Mike Szczys 36 Comments

homopolar-motor

Slow day at the office? Here’s a trick that’ll make your coworkers smile. Dangerously Fun has a guide to build a homopolar motor from a battery, copper wire, and magnet. A homopolor motor doesn’t rely on electromagnets in an armature changing their polarity to force a rotation movement compared to stationary magnets. Instead, they use an electrical current’s orientation to a magnetic field to provide a repulsive or rotational force. In this implementation, the current moves through a loops of copper wire from one pole of a battery to the other. A rare-earth magnet on one pole of the battery provides the magnetic field.

After the break we’ve embedded video of this simple example as well as a few more complex homopolar examples such as a five speed version. The motor in action certainly brings a smile to our faces and places this firmly in the useless machines family of hacks.

Continue reading “Homopolar Motor” →

Servoelectric Guitar Is A Keytar With Strings

November 6, 2009 by Mike Szczys 18 Comments

servoelectric-guitar

[Keith Baxter] has undertaken something of a ‘Mount Everest’ of guitar modifications. He’s developing a Servoelectric guitar that trades frets for a keypad. It is still a guitar in the sense that it has a body, strings, and pickups to sense the strings vibrations and pass them to an amplifier. The left hand, which traditionally would shorten the strings as needed by pressing them against a fret, now changes string pitch using a keypad. This is an interesting fusion between traditional guitar and 80’s phenomenon, the keytar.

Each string is connected to a different servo motor. When a key on the keypad is pressed, the corresponding servo adjusts the tension of that string, bringing it in tune at the new pitch. His original design involved a lot of custom circuitry but he’s evolved the project to include an Arduino controller. This second generation both simplifies the control circuitry and improves upon it.

We’ve embedded some video after the break. In the first example you can see the strings adjusting for each new pitch. In the second, take a look behind the guitarist… what do you think he’s got planned for those giant capacitors?

Continue reading “Servoelectric Guitar Is A Keytar With Strings” →

25 Scariest Experiments

November 4, 2009 by Caleb Kraft 113 Comments

[youtube=http://www.youtube.com/watch?v=Jq06D0xRWmc]

Warning: This video contains actual footage of a severed dog head, kept alive. Watch at your own peril.

[Annalee] over at io9.com has gathered together the 25 scariest science experiments. There are some truly frightening pieces, like the cyborg beetles which we’ve seen before, all the way to silly stuff like the guy who re grew his thumb using pig powder. Next time you’re thinking of admonishing someone for creating a flamethrower, or a super fast scooter, consider for a moment that they’re not burning peoples nasal passages to stop masturbation or creating zombie severed dog heads like the one in the video above.

Ping-pong Launcher Your Wife Can’t Know About

November 2, 2009 by Mike Szczys 27 Comments

ping-pong-ball-launcher

Sometime the projects you see at the local hacker space are better left a secret when you return home for the evening. Case in point, this ping-pong ball launcher that can put holes in a sheet of OSB. The projectile is made more lethal because the ball has been injected with water to dramatically increase the density. Compressed air is used to propel it from the 14 round magazine with devastating effect.

We’ve embedded a video of the gun being fired after the break. The creator, [Ron Kessinger], demonstrated this at a Denver hacker space called Club Workshop. We’re hoping there’s no plans for turret automation because this thing’s dangerous! Either way, the significant other who usually watches out for our safety would never approve. Continue reading “Ping-pong Launcher Your Wife Can’t Know About” →

We’ll Take The Fries.

November 1, 2009 by Jakob Griffith 32 Comments

fjdkalfjdklajfdaflj

We’ve all been there; hardest decision we’ve ever had to make. College and debt or freedom but no career? Start a family or live out alone? The number 2 with a small shake or side of fries?!

[Leon] sent in his random number generator, oddly enough not to just generate a number, but help us through with those life altering decisions. Using a noise diode like setup he’s able to generate random bits, which an ATtiny24 then converts and displays on a 7 segment LED. His generator also has the ability to set upper and lower limits. Seems like an awful lot of work to avoid the freedom of choice paradox, but we enjoyed the project none the less. Check out a video after the break. Continue reading “We’ll Take The Fries.” →

How To Create TrueType From An Image

October 30, 2009 by Mike Szczys 13 Comments

making-truetype-fonts-from-images

[Viacheslav] wanted his virtual terminal to have the look of a DEC VT220. He was unable to find a font set that looked just right so he set out to make his own TrueType font. He managed to find a sample image of the glyphs that the VT220 used as fonts. Using a collection of free software he sliced the image into 256 different parts, resized and converted to one-bit index images, and converted these to vector graphics. This was accomplished with a bit of python, an image tracing program, and font editor called FontForge.

Take some time to dabble with these font tools. With an adequate sample you should be able to reproduce any font set. We won’t achieve anything as sophisticated as the font printed with bacteria, but this will be a start in the right direction.