November 9, 2009 4:29 PM PST

The DIY secret-knock door lock

by Matt Hickey
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secret-knock door lock

DIY'er Steve Hoefer used a piezo speaker, a tiny gear reduction motor, an Arduino, and a PVC pipe to make his secret-knock door lock.

(Credit: Steve Hoefer)

I've been hearing more and more about the Arduino microcontroller project lately, and this is by far one of the coolest uses for it I've seen. Arduino is an open-source hardware project meant for easy prototyping of hardware ideas. This is Steve Hoefer's great vision for a mechanism that opens a door when it detects a secret knock. Here it is in action:

As you can see, he's programmed the microcontroller to listen for a specific knock sequence. When it hears it, it turns the deadbolt, meaning you can open the door. It's a simple but genius idea.

We're hoping something like this comes to market. Sure, it's not the most secure idea in the world, but it's fun enough that it'd be great for the inside of homes or backyard sheds or underground sex dungeons.

With more than 15 years experience testing hardware (and being obsessed with it), Crave freelance writer Matt Hickey can tell the good gadgets from the great. He also has a keen eye for future technology trends. Matt has blogged for publications including TechCrunch, CrunchGear, and most recently, Gizmodo. E-mail Matt.
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by CarlinJ216 November 9, 2009 8:02 PM PST
Very cool
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by mtf612 November 9, 2009 11:46 PM PST
i want one!!!
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by justnlukemyers November 10, 2009 5:33 AM PST
LOL@ underground sex dungeons.
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by c|net Reader November 10, 2009 9:53 AM PST
I found that distasteful and inappropriate for a widely read, mainstream technology blog.
1 person likes this comment
by HamSammy November 12, 2009 8:25 PM PST
cool story bro
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