Motion sensor v2 built and in use

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:

v1 upgraded to v2

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! ๐Ÿ™‚

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, 100ยตA 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?ย  ๐Ÿ™‚

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:

Motion v2 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.

Update 2010-09-16:

The sketch that’s currently running on these sensors can be found here; the Sleep library i currently use can be found here .

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3 Responses to Motion sensor v2 built and in use

  1. John S. says:

    Just wondering how this system compares to say the jee labs “room board” and a JeeNode 4, which is one option I was thinking of. About $70 for both in US dollars. The room board is nice because it has sensors for temp, humidity, motion and light, all on one board the plugs into the JeeNode 4..

    The Xbee’s could poll sensors without the need of a jeenode as well. Something I have thought about trying. Just program the xbee for sleep intervals, tell it what pin the sensor is on and it will do it. That method ends up being $60 per sensor.

    I really like everything you have done here. It’s motivated me to try accomplish some of what you have done for myself.. Just wondering if any of your code for the website is available for public use?

    • A JeeNode room board does indeed have more sensors than the devices i am building. Basically because the first motion sensors i built were destined for living room and kitchen where i already have temp, humidity and light so that would be redundant. Some devices that will be built in the future will have more sensors, like temperature and light. I’m working on that (slowly…).
      If you want it all in 1 package, the room board is the best choice I’d say.

      And you’re right that you could use just a XBee without JeeNode for some types of sensors but it makes it less flexible IMO; for instance you could disable motion detection when it’s dark with a JeeNode; something you can’t do with a single XBee. That’s the beauty of it; you can make it as you want it to be, it’s your choice ๐Ÿ™‚

      Sometimes I add a link to a sketch, but often i just forget about it; it’s not intentionally, so what I will do is edit this post soon and add a link to the code.

  2. Pingback: PIR13 Motion sketch progressing

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