The Don’t-Leave-Home-Without-It Machine

The Don't-Leave-Home-Without-It Machine prototype on a blue background.

If there’s anything in the tray, the circuit automatically sounds an alarm when you approach the door to remind you to take it with you.

My first project for littleBits was this machine that automatically reminds you to take your valuables with you when you go out. To use it, set it on a shelf or table beside your door, with the sound trigger Bit microphone pointed towards it. Plug in your power supply, turn on the power Bit, and put your forget-me-nots inside the tray. One LED will light up to indicate that the device has detected an object and is ready to trigger when you go out the door. Test it by snapping your fingers or blowing into the microphone, which should set off a second, flashing LED and a ringing bell. Because the bell is right next to the sound trigger, the sound from the bell should reactivate the alarm cycle over and over again, keeping it going until you remove the objects from the tray.

I learned to use Lightworks to make the accompanying video, and had a great time with it. Amazing that this software is available for free. The Giant Snow Globe project featured in the video is one of the first I ever produced for Make: Online.

The Don’t-Leave-Home-Without-It Machine :: instructables.com

The Don’t-Leave-Home-Without-It Machine :: littlebits.cc