Last week I had some trouble getting out of bed during the night without hurting myself. So this evening I decided to do something about that; I need something that can light the floor while someone is walking through the bedroom at night. So I made a list of things with which I could make something useful for that:
- An Arduino Duemilanove;
- a Protoshield;
- 2 PIR motion sensors;
- a LDR;
- a IRLZ34N MOSFET to drive the LED strip;
- a 12V power adapter;
- about 2 m. of white LED strip;
- 2 LEDs (one for power and the other for motion detection);
- an Arduino enclosure.
There it is… our automatic bedroom floor lighting is being tested at this moment. The 2 PIR motion sensors will be mounted under the bed in a way that they will only be able to detect motion caused by moving legs, the LDR will be used to detect whether it’s dark in the bedroom or not and the white LED strips will be glued to the bottom side of the bed and will light the floor when motion is detected.
The fun thing is that this floor lighting is almost completely built from spare parts (except the enclosure). The 2 PIR motion sensors were the first motion sensors I ever bought, but the lenses were too big for my taste to actually use them. Under the bed the size of those lenses doesn’t matter. The Duemilanove is one of the many Duemilanoves I have laying around for testing/experimenting, so I can easily do with one less – I could also have picked an RBBB, Teensy or JeeNode. The number of unused protoshields made me decide for an Arduino. And all the other parts were all purchased in the past with the thought they’d be handy to have around for when you suddenly need them 😉
No RF, Zigbee or Ethernet this time – this will be a solution that doesn’t need any other external input, nor do I think I’ll use the fact that someone’s walking through the bedroom in the rest of my system. Nevertheless, I’ll reserve some space on the Protoshield for a XBee Breakout board cause this would actually be a very good place for a Zigbee router on the 2nd floor!
The sketch will be a collection of code from other sketches I’m already using, so I hope that at the end of this week I can finish this and never hurt my toes again 😉