Motion Sensor
Posted: Thu May 27, 2010 11:01 pm
No, this is not some special add-on for my ASUS TOP.. it's just a Duemilanove with a PIR sensor attached to it:
And the ASUS TOP, which is being used as my Domotica GUI in the living-room, is only used to provide power to the Duemilanove.
Somewhere in October 2009 i bought 2 PIR sensors, but after some brief testing these PIR sensors were stored in a drawer and nothing has been done with them since then. Since i intend to create my own motion sensor someday, i put one of these PIRs on a breadboard and attached it to an unused Arduino. And of course, the most logical place to test this sensor and learn something about how it performs, is the living-room. The office is to small to learn anything about how this sensor behaves with motion from different angles, distances and the output it provides. A breadboard with the Duemilanove, PIR sensor and LED, stuck to the ASUS TOP with tape, seemed like the best compromise for real life testing without making the living-room look like it's an extension of my hobby room.
From what I've seen so far, this sensor is sensitive enough to be used successfully, although the digital output is not as stable as i expected. During continuous motion (as in my daughter dancing in front of the PIR for 2 minutes) i still saw the digital output dropping to 0 (meaning no motion) for a large number of short periods. Strange? Well, at least it's not what i expected..
This means i'll have to add some debounce logic into the code that handles this PIR to eliminate unwanted transmissions of these "no motion" events; cause if i don't, i'm pretty sure i can change batteries every couple of weeks... cause that's the goal of all of this; creating my own battery powered motion sensor.
What i'm really looking forward to is putting the sensor in it's own, very small case and place it at the best spot for motion detection and put the rest of the hardware (batteries, JeeNode and wireless stuff) in another box, somewhere nearby but out of sight...
Yes, you can do that if you DIY
And the ASUS TOP, which is being used as my Domotica GUI in the living-room, is only used to provide power to the Duemilanove.
Somewhere in October 2009 i bought 2 PIR sensors, but after some brief testing these PIR sensors were stored in a drawer and nothing has been done with them since then. Since i intend to create my own motion sensor someday, i put one of these PIRs on a breadboard and attached it to an unused Arduino. And of course, the most logical place to test this sensor and learn something about how it performs, is the living-room. The office is to small to learn anything about how this sensor behaves with motion from different angles, distances and the output it provides. A breadboard with the Duemilanove, PIR sensor and LED, stuck to the ASUS TOP with tape, seemed like the best compromise for real life testing without making the living-room look like it's an extension of my hobby room.
From what I've seen so far, this sensor is sensitive enough to be used successfully, although the digital output is not as stable as i expected. During continuous motion (as in my daughter dancing in front of the PIR for 2 minutes) i still saw the digital output dropping to 0 (meaning no motion) for a large number of short periods. Strange? Well, at least it's not what i expected..
This means i'll have to add some debounce logic into the code that handles this PIR to eliminate unwanted transmissions of these "no motion" events; cause if i don't, i'm pretty sure i can change batteries every couple of weeks... cause that's the goal of all of this; creating my own battery powered motion sensor.
What i'm really looking forward to is putting the sensor in it's own, very small case and place it at the best spot for motion detection and put the rest of the hardware (batteries, JeeNode and wireless stuff) in another box, somewhere nearby but out of sight...
Yes, you can do that if you DIY