Here’s the proof that Arduino is a tool for serious prototyping and not just a toy. [Norbert Požár] built a magnetic levitation device that combines an Arduino with an electromagnetic driver circuit and a magnetic field sensing circuit. Unlike other other levitation setups that use optical sensing, this implementation uses a hall effect sensor on the electromagnet to maintain the distance between it, and the permanent magnet it is holding in midair. Check out the embedded video after the break and browse through the overview page so see how pleasing it is to do away with a frame around the floating object. This makes us wonder if it could be inverted in a way similar to that magnetic scale.
magnetic45 Articles
Hackaday Links: October 17, 2010
Cards you should crank
These greeting cards must be the product of a mechanical engineer run amok. They come with a crank and are designed to entertain with their simple, yet elegant movements. [Thanks Phil]
Magnetic card stripe reader
[JP] built an Arduino based magnetic card reader. It uses off-the-shelf parts but if you don’t mind buying the components this will get you up and running in no time. If you want more info there’s also this Teensy based version.
Homemade Airsoft sentry gun
This sentry gun has an amazingly fast firing rate that can continue for quite a while, thanks to the big flashlight housing that is holds a lot of ammo. [Thanks David]
Scanner easter egg
The engineers over at HP had a little fun building an easter egg into this scanner. If you know what you’re doing you can get it to play the Ode to Joy. It needs to join the old-hardware band from our Links post earlier in the month. [Thanks Googfan]
Teensy Credit Card Reader
Here’s a hack that makes business sense. [PT] recalls last year’s HOPE conference when their booth was using a virtual credit card terminal for purchases that required manual entry of card information. This year they’ll have the same virtual terminal but this magnetic stripe reader will fill it out automatically.
A magstripe reader (reading only, no funny business here) from Mouser grabs data from the card. A Teensy microcontroller board, which identifies itself as a USB keyboard, automatically fills out the virtual terminal from the parsed data. The real question, are his customers comfortable sliding their plastic through a hacked reader?
Radio-Walkman-megaphone Hybrid
[Erich] rethought the use of a megaphone and ended up with this Mega-Tape-O-Phone. His first move was to ditch the megaphone’s amplifying circuitry in order to add his own based on an LM386 chip. From there a radio receiver joined the party followed by the guts of a tape player. He relocated the head of the tape deck to the end of a flexible cable and coated the outside of the megaphone bell with magnetic tape. Now he’s surfing the airwaves and scratching away happily.
The use of the tape head has been seen here before, but it was never in a mobile package like this is. Join us after the break for some video of this in action.
1000W Induction Heater
[Tim Williams] likes to heat things up with this induction heater he built. At peak it can use 1000W and as you can see in the video, that’s more than enough power to heat, burn, and melt a plethora of different objects. The case design uses a center divider to isolate switching noise from the magnetic field with the whole unit housed in aluminum because it won’t heat up from stray magnetic fields. He’s selling plans and kits in case you want one, but we just don’t know what we’d use it for.
Hand Made Manipulator Arm
We’re pretty used to seeing CAD used in the design process for most things. It’s a bit of a shocker to come across a project this involve, and this well executed, that didn’t use CAD.
[Anton] spent 100 hours building this manipulator arm by hand. He made the parts by drawing them on styrene and cutting them out with scissors. He has started building version two with AutoCAD but from what we’ve seen in the video after the break, improvements on the original design will be minor. The speed and fluidity of the servos with added magnetic encoders makes for a graceful robotic dance; we’d love to be its chess partner. Continue reading “Hand Made Manipulator Arm”
10-bit Rotary Precision For Servos
[Antonb] added 10-bit encoding to a standard servo. He’s removed the potentiometer, separated its shaft and used it to rotate a small magnet. By sandwiching an AS5040 rotatory encoder IC into the servo’s housing he can now measure the precise orientation of the servo horn. This is made easier by his tiny breakout board for the chip. If you want to layout your own PCB you can download the EagleCAD files for this device. Take a look at the final product in the clip after the break.