Two motion sensors v2 are in use right now, yippee!
I upgraded an existing v1 sensor to a v2 and built a new one. The v2 sensor specs are very different from the v1 but much more promising, yet all i needed to do to was soldering the digital output of the PIR to another JeeNode port (namely ATmega INT1) and use a different digital port for serial I/O with the XBee. Oh, and upload a new sketch of course. Now i have 2 identical v2 sensors:
Looking back at how this motion sensor evolved i am wondering, why didn’t i think of interrupts in the first place… not very smart actually..
Or maybe i did think about interrupts but unconsciously thought it would be to hard for me to handle already, cause that’s what you read all the time: interrupts are a tough subject! Maybe it is, but i didn’t notice that yet! 🙂
So now I’ve got 2 motion sensors with the following features:
- powered by 3 * 1.2V, 2000 mAh rechargeable batteries;
- PIR with digital output, 100µA standby power usage and 5m detection range;
- a JeeNode that’s effectively running only a total of about 180 seconds per day (0.2 %), even with 350-400 motion reports and lots of heartbeats. The rest of the time the JeeNode is in power down mode;
- it’s ZigBee based which is better than 433 MHz in my opinion, especially when you’ve got a lot of sensors;
- relatively small sensor housing compared to commercial (mostly big and ugly) products;
- completely DIY so everything is how i want it to be;
- interrupt-based, the best you can get I’d say;
- need i go on? 🙂
I’m gonna monitor this sensor very closely in the coming months and learn from it. Here you see one of the sensors being used in the kitchen:
Finished? Almost; some loose ends in the sketch. Maybe it can be made even smaller/faster/less energy consuming. But I’ll look into that when the 3rd sensor is built.