The mother of invention may be necessity, but French telecom engineer Clément Storck learned his father can play that role too. To remind his forgetful dad to close the garage door, Storck rigged it with a switch that triggers an iPhone alert—a home-automation hack that joined his repertoire of self-closing shutters and a tweeting cat door (see @PepitoTheCat). But Storck’s greatest hack yet is a webcam that e-mails a photo of anyone who rings the doorbell. Follow these steps to build your own—and end speculation over whether it’s UPS at the door or a prankster with a flaming paper bag.
Time: 1 hour
Cost: $100 or less
Difficulty: 2 out of 5
1) Set Up A Webcam
Aim a webcam at the welcome mat (wireless models are the easiest to install). Configure the camera to constantly refresh an image to a dedicated Web host.
2) Give The Bell A Brain
To imbue your doorbell with artificial intelligence, set up an Ethernet-enabled Arduino microcontroller nearby. Then grab the source code from here (Storck and two friends made the service specifically for this and other home-to-Web hacks).
3) Create Web Notifications
Navigate to My Scenarios on PushingBox.com, click Add a Scenario, and configure the entry to e-mail yourself photos. Be sure to include the webcam’s URL, click Test to verify the configuration, and copy the 16-character DeviceID.
4) Program The Arduino
Paste the DeviceID into the downloaded Arduino code in the quotation marks after the line “char DEVID1=” and upload the code to the microcontroller.
5) Test Your Spy Cam
Every push of the doorbell completes an electrical circuit, which tells the Arduino to download the latest webcam image and send it to your chosen e-mail address. Your doorstep self-portrait should arrive in a few seconds.
For more detailed instructions on how to make the doorbell spy cam, check out this PDF.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.