Month: November 2007

Automatic Projector Calibration

November 15, 2007 by 40 Comments


[Johny Lee] sent in his(pdf) awesome projector calibration project. By adding embedding some optical fiber that feed into a set of USB connected light sensors, his groups software can determine the exact pixel position of each sensor. Once the positions are determined, the projected image can be dynamically adjusted to fix the screen. The technique can be used to stitch together multiple projectors, and even calibrate an image to project onto a three dimensional model. I know some home theater nuts that would love to have this system for calibrating their CRT projectors.

This is such an excellent project, that I want to give credit where it’s due – it was developed by [Johnny C. Lee], [Paul H. Dietz], [Dan Maynes-Aminzade], [Ramesh Raskar] and [Scott E. Hudson].

Be sure to check out the video demo after the break!

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Toilet Terror Level Indicator

November 14, 2007 by 11 Comments


Normally, this wouldn’t quite make my radar, but [sprite_tm] built it, and it’s funny as hell. He created a Terror Level indicator for… his toilet. Rather than create an exotic smell detector, he simply uses a photo diode to measure the amount of time that the light has been on in the ol’ water closet. As time progresses, so does the Terror Level indicator. To make an audible indicator, he used the PWM generator in the ATTiny231to create a sort of ping sound when the level escalates. (I can definitely think of someone I need one of these things for.)

Simple VGA Test Box

November 13, 2007 by 6 Comments


Sometimes it may seem like I suffer from goldfish memory. [Chris] sent this in a while back and I’d almost forgotten about it. He built a simple VGA test box using a PIC 18F452. I’d probably be more interested in using it to add simple VGA output to another project than use a test box, but it can definitely be handy if you need a small portable video test signal.

Blowable Computer Interface

November 12, 2007 by 18 Comments


Remember Christopher Reeve’s blow controlled wheel chair? [Shwetak] sent in his blowable computer interface. It doesn’t require anything but an on-board microphone and a decent set of lungs. It works by taking audio fingerprints to determine the location on the screen that you’re exhaling on. The demo video (avi) shows off some surprisingly accurate location detection. You can get a few more details from his research paper. (If you need a decent avi video player, check out VLC player.)

HackIt: New Life For Old Laptops?

November 11, 2007 by 161 Comments


Last time, I challenged everyone to shout out with new ideas for those old TiVo boxes. The response was fantastic. I’m not feeling too exotic tonight, so I’ll make it easy: The laptop. Years ago I found an article on using old laptop screens to make an electronically dimmed window. At tie time, LCD panels were $1000 items. Today, screens and old laptops can be picked up for a song.

Since ‘Hackit’ is a new idea, I’m still working out just how I’m going to handle it. Each week I’m going to bring up some hardware. You guys get to pick your brains and suggest new, interesting projects. Every so often, I’ll tally up some of the best ideas and put up a bounty for pulling one of them off. Maybe it’ll be cash, maybe some spiffy hardware – I’ll let you know when we get to it.

So, got a better idea? Let’s hear it.

Upgrade Your In-ear Headphones

November 11, 2007 by 25 Comments


I’m a fan of my Etymotic er6i (which have mysteriously vanished…) headphones, so this simple hack caught my eye. [James C] sent in this simple method of upgrading the more affordable apple in ear headphones. The idea is simple, use a small hole punch to cut out the center of some cheap foam earplugs. Then replace the soft surrounds on the headphones with them. I’m guessing that this trick would work for quite a few in ear headphones that I’ve seen lately.