Build Your Own Magnetic Levitator

Here’s a great magnetic levitator build. [Scott Harden] dug up the link after seeing that awesome rotating globe this morning. This version hangs objects below an electromagnet but it has a sensor system to provide a constant distance between magnet and object even if the payloads are a different weight. This is done with a couple of infrared sensors. One acts as a reference detector, always viewing an IR LED in order to get a baseline measurement. That measurement is compared to a second detector mounted slightly lower. The circuit adjusts the electromagnetic field, making sure the object is always breaking the lower beam but never interrupting the reference beam. No microcontroller needed, this is handled with a couple of OpAmps. See it in action after the break.

Continue reading “Build Your Own Magnetic Levitator”

Manual Transmission Gear sensor

[Ben] bought a remote starter for his car but needed a way to make sure the manual transmission was in neutral when starting. He built this infrared sensor frame to detect the position of the stick. It uses four beam paths which will tell him the exact gear or neutral position of the shifter. For this project he just needs to detect neutral but exact gearing is apparently necessary information for his next hacking project. We initially were worried about sunlight interfering with the sensor readings but he’s building this to go under the collar that is used to cover up the mechanical joint at the base of the stick.

Update: IR Controlled Lighting

[Muris] is back with another infrared controlled lighting hack. When we checked in with him last year he was showing off an IR controlled dimmer module. Now he’s back with this device that is CFL friendly. Because standard CFL bulbs are not dimmer compatible he’s adapted the project away from dimming and toward switching. The new design still uses an infrared remote but now it can turn two devices on and off again or toggle between them. Our favorite part of the build is that the PIC based device can learn the codes of whichever remote you choose, rather than having to rely on one specific type of remote.

Infrared Transmission Decoding

Alright class, quiet down and open your books to the chapter on Manchester Encoding. [Brian J Hoskins] did just that when building this RC5 decoder. This protocol is commonly used in television remote controls. You use them on a daily basis, don’t you think it’s time you understood what’s going on? Check out his writeup and learn the dark art of invisible light communication. Or just skip the learning and follow our how-to.

[Thanks Tim]

Location Tracking Using IR Throwies

[Joe] and his team hacked together some location tracking using IR throwies for their final project. The challenge they undertook was to find a way to track the orientation of a sculpture in the form of a rotating metal cube. The end result dips its toe into the augmented reality pool but the methods are what interest us.

They wanted this to work day or night so contrast would be a major issue if working completely with image manipulation. Having a simple way to pick out the corners of the monotone block would make this process a breeze. They ended up using magnetic throwies that have an infrared LED which can easily be picked up by a webcam no matter what the ambient light issues happen to be.

After the break you can see these guys out in the wild testing the system. We’d like to note the diffusers used in the project. We’re used to seeing ping-pong balls as diffusers but this is the first time we’ve noticed Styrofoam balls being used.

Continue reading “Location Tracking Using IR Throwies”

Mac Mini – Getting A Little More Useful

IMG_7559

We’re pretty sure Apple decided to implement an IR sensor in their Mac Mini line simply to mock the user. For those who are unaware, the built in sensor only works with the standard Apple Remote; unless you happen to have a programmable PDA or similar you’re SOL. An alternative solution would be to install a USB IR receiver. But then your beautiful Mac Mini is forced to sit alongside an ugly black box. Why not have the best of both worlds? [SqueeZe] wrote an (almost) entirely non invasive tutorial for placing a USB IR receiver inside his Mac Mini. Reminds us of a certain hack a while back, but the objective was to get the IR receiver outside of the unit rather than inside. Different people, different worlds.

[Thanks Kiran]

TV-B-Gone-zilla! Rawr!

tv-zilla

TV-B-Gone: antisocial nuisance or harmless prank? Whatever your feelings, there’s no denying this device has become a staple of the DIY hacking crowd, as evidenced by the countless derivatives since hatched. This latest mutation crushes them all.

[manekinen] from the Polish electronics blog Elektroda (“Electrode”) wasn’t satisfied with high-power TV-B-Gone designs using multiple 5mm infrared LEDs, so he created his own using a single one-Watt monster. The device is concealed in an ordinary flashlight casing, making it somewhat inconspicuous. A custom PCB containing an ultra-minimalist version of the TV-B-Gone circuitry sits just behind the reflector. The choice of reflectors determined maximum distance vs. coverage…they opted for distance. Specific figures aren’t given, but we estimate this thing could shut off televisions on Mars.

The original article (Polish or Google-ized English) includes construction photos and an archive (.rar) of project files including Eagle schematics and C source code.

Would it be totally irresponsible to mention there’s now a 3-Watt version of this LED? We’re just sayin’.

[thanks RicoElectrico]