Home Hacking Projects for Geeks

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Part I: Home Automation

Motion Detection

You want to take a picture only when your pet is active, so you need to

know when your pet is moving and which room he is in. As you’re probably

well aware of by now, this feat can be easily accomplished using motion

detectors.

For this project, you have two main considerations when choosing a motion

detector: it needs to connect to your Linux computer (which is located in a

different room) and it needs to be cheap. After looking around on the Web,

I decided the best option was a wireless X10 motion detector. They cost only

$20 each, they’re wireless and battery powered, and a Linux computer can

intercept their signals using a simple script.

1. Install X10 light switches or lamp modules

The webcams you’ll be using in the Image Capture phase of this project

can’t see in the dark. In fact, they produce terrible pictures in anything less

than bright sunlight. So, if you want to capture pictures of your pet moving

around in the evening or in a room without bright natural light, you’ll need

to add some X10-enabled lighting.

If you’ve already replaced all the light switches in your house with X10

light switches, or if you’re using night-vision cameras, you can skip to the

next step. If not, and you want to capture pictures 24 hours a day, you’ll

need to replace the light switches in the relevant