In case you haven't seen it, AirWick FreshMatic is a small device to automatically spray the air refreshner on given time interval. Recently I came across another version that also has a motion sensor built in, and I though it would be good source to get a motion sensor. Since it was on sale for around 10 Euro I bought one.
When I took it apart I found a nice, big DC motor and two connected boards: one with the microcontroller and second with the motion sensor and green LED. I found that the motion sensor board sends the signal to the controller by pulling one of the output pins LOW. So it can be easily cought using interupt on Arduino.
Now it occured to me that I could use not only the sensor but also repurpose the whole box to host the JeeNode and other sensors. Since I don't have JeeNode yet, I used full size arduino and pair of Xbees, but it all fits nicely inside the box. I also added a temperature sensor (D18B20) and a photoresistor. I had to modify the Room sketch a bit to use my motion sensor and report via serial instead of RF18.
Here you can see few photos on how it came together:
http://cid-4c7ec0c2176a0b0d.skydrive.live.com/self.aspx/Environmental%20electronics
So I'm happy to report that first node of my network is already on duty and reporting data. And I already have another AirWick waiting to host the JeeNode :-)
Please let me know what you think.
