Keyless Entry Using Touch Sensing

[Alex] sent us this slick little keyless entry system. He wanted a discreet way to trigger the door to unlock. Knocking was too loud, and would give away his secret access code. He decided that touch sensors would be the best. Initially he planned on using the doorknob itself, which would have been awesome, but it was just too much surface area for his touch sensor. Ultimately, he settled for a wire he could touch.  An Arduino detects whether or not the correct code has been put in and initializes a high torque servo which turns the doorknob from the inside.  In the video, after the break, you can see that it works fairly well.

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Build A Solar Dehydrator

[Erik Knutzen] and [Kelly Coyne], authors of The Urban Homestead, are really into all things green and sustainable. In their blog, Homegrown Evolution, they discuss building their own solar dehydrator using plans from the February/March 1997 issue of Home Power Magazine. The dehydrator is designed by Appalachian State University’s Appropriate Technology Program. If interested, you can check out or buy other solar dehydrator designs. This seems like a great, cheap alternative to buying an expensive electric dehydrator, and you get some great advantages, like low-cost dehydrating, solar energy, and beef jerky whenever you want it. Plus, the authors point out, for most of these designs, if you remove the top box and you stick it next to a window, you’ve got a solar heater. It’s now a dual-purpose device.

A Remote Controlled RGB Light Bulb Lamp

RGB just got a lot brighter by using 3x60Watt flood lights instead of an LED. The bulbs are driven via TRIACs and the whole thing uses a remote control to change the levels of the three bulbs. It is also able to store these levels for later recall. The IR receiver was taken from a dead TV set along with its remote control, or a universal remote set to a Phillips TV can be used. The source code and schematic for this project are available.

Fatality And A Frosty Mug: Arcade Bar

We’ve seen our fair share of home made arcade machines, some complex and some simple. This one stands head and shoulders above the rest with its ability to combine two of our deepest loves: beer and video games. There’s not a lot of information, just a few pictures. We’d love to see some build shots or action shots.  We’d love to test it out actually.

Here’s an update: [Burke LaShell] is the maker of this fine project. You can see more pictures of it in this thread. Thanks, [Shawn].

[via Gizmodo]

Real Time Gas Monitoring

With the weather getting colder, [Daniel] decided it would be a good idea to monitor how much energy his gas heating was using in real time. He used a Nokia 6680 cameraphone to monitor the heater’s flame through the sight glass. PyS60, a Symbian implementation of Python, checks the image sent by the camera and measures how much blue flame is visible. These values are stored in a SQL DB on the phone that can be polled over Bluetooth. At the end of the billing cycle,  he’ll be able to correlate the amount of gas used with what the phone reported.

[Thanks, florent bayle]

Hack Your Litter Box


Cat poo stinks.  We all know it. Those of us who have cats, though frequently amazed at the sheer magnitude of stench our cuddly friends are capable of, do little to remedy the situation.  Sure, sometimes we buy the fancier kitty litter or the special food.  [agraham999] decided to be a little more proactive.  He built an automated exhaust system for the litter box. He wasn’t content to just rig a fan blowing to an exhaust vent either, he hooked it up to an automation system and a motion detector.  The total cost for the project was $80, not including the mac mini that serves as the brains.

Be sure to read through the comments for some very in depth discussion about power usage and solar conversions.

[via Boing Boing Gadgets]

LED Random Blinking Mood Lighting

What is it about pseudo random flashing LEDs that make us go gaga?  We don’t know, but there’s definitely something there. [seligtobiason] has this obsession too.  After seeing several more complicated projects, he created this elegant, simple, and cheap piece of art. The entire thing is pretty much just some flashing LEDs, some resistors, and a power supply.  It really isn’t anything groundbreaking, but the effort and cost involved are tiny compared to some other similar projects.  sure, it doesn’t synchronize over time based on input like the firefly project.   But for a quick cheap project, the results are quite nice.

We would put one in our home, right next to the node blinky.