Making A Rail Gun (again!)

January 1, 2010 by Jakob Griffith 24 Comments

[Rp181] is at it again with version 2 of his rail gun project (link dead, try Internet Archive). The original did have some power with 18 400V 3900uf capacitors, but he’s ramped it up to now using 40! Reaching more than double the amount of joules of energy, 12kJ vs. the 5.6kJ! Some other changes include a new injector solenoid setup and revision 3 of his breakwire chronograph. Sadly, he doesn’t mention if this is as green as his first rail gun. Check out a video of just the injector firing and an animation explaining some new updates after the jump.

Continue reading “Making A Rail Gun (again!)” →

Simplest Most Useless Machine

December 30, 2009 by Mike Szczys 42 Comments

[youtube=http://www.youtube.com/watch?v=Z86V_ICUCD4]

[Brett] posted about his most useless machine build. His project gives us a chance to massacre the language in the title because it uses the lowest parts count we’ve see with these machines. The logic is controlled by our friend, the 555 timer. Add to that just one servo motor, two switches, three resistors, two caps, a diode, and a battery pack and you’re in business. The hardest part to find locally is the servo but check at a hobby/RC store. If you don’t have to put in a parts order this can be your next impulse project.

Shadow Buttons

December 28, 2009 by Mike Szczys 7 Comments

This art installation uses buttons made of light. A projector fills up the walls and ceiling of a room while a webcam monitors the pattern for changes. When the luminosity of a given area changes due to a shadow, a midi event is triggered. The software that controls the system is written in C# and uses the Emgu CV library to handle the image processing. In the video after the break you can see that creating shadows with your hands prompts changes in the image as well as the sound.

Continue reading “Shadow Buttons” →

RFID Control Concept

December 26, 2009 by Mike Szczys 3 Comments

That’s not a smoke detector, it’s an RFID detecting puck. [Eric] and [Brent] have been working on this concept to produce a virtual knob. When the device detects an RFID tag it vibrates, then the puck can be turned like a virtual knob, an accelerometer picking up the motion data. The build is rounded out with a XBee module for connectivity and housed in a printed case.

The video after the break shows the device controlling colored lights. There is a different tag for each color and when the reader is over one of them the puck can be rotated to turn brightness up or down. We foresee a lot of great uses for this. Turn it into a thermostat for public places by adding a character display to the mix. A tag can be affixed to a wall, when you want to change the thermostat setting just hold the puck over the tag and turn until the screen displays the desired temperature.

Continue reading “RFID Control Concept” →

Missile Command On IPhone With Real Missiles

December 24, 2009 by Mike Szczys 13 Comments

[Jeff] and his team completed this iPhone controlled rocket launcher as part of their final project at Georgia Tech. Two servos provide the rotation referenced by an onboard electronic compass, and elevation control for launch. These are interfaced with an eBox 2300 using a few Phidgets boards.

Check out the launch video below. It’s too bad that they went with a commercial solution for servo control rather than building it themselves (especially considering it is an embedded systems class). But it is a nice build none the less. Now they need to add some imaging equipment to the rockets and they’ll be in business.

Continue reading “Missile Command On IPhone With Real Missiles” →

Punching Out Parts

December 22, 2009 by Jake W 13 Comments

If you’re more of a code monkey than artist, it may be tough to transform your ideas into the 3D models necessary for fabbing. The folks working on openSCAD apparently feel our pain.

openSCAD uses a language somewhat reminiscent of C for creating models. A preview of the model is rendered alongside your code. Fully cross-platform, it runs on Linux, OS X, and Windows. Much like SketchUp, openSCAD can also extrude 2D outlines into models. This feature comes in very useful if one already has a set of technical drawings for a part. With no price tag, it’s pretty affordable during this costly season.

C-clamp Current Monitoring

December 21, 2009 by Mike Szczys 24 Comments

[Hydronic] did some tests to make his own current sensor using a c-clamp wrapped with wire. He tried several different cores including an aluminum carabiner, the C-clamp, and what he calls a u-lock (removable chain link). There is some success here that could be improved with cleaner winding and by adjusting readings based on the length of wire used in the wrapping.

This did make us perk up a bit right off the bat. Reader [Mure], who tipped us off about this, suggested that this could be used to make your own Kill-a-Watt without including it in the circuit. We made the jump to house monitoring. We’d love to have a data tracker for our home circuits to curb wasteful energy use. Perhaps we’ll try to make our own sensors and produce a diy Cent-a-Meter.