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[on:]

Hi there,
I need to build a small device using a wireless module to send data not continuously (trigger just a character sent when a small accelerometer detect a fast movement)

I need to put the whole stuff in a box.

first question: is there a box that can contain Arduino 2009 + WiFi shield ?
I found this one , but not sure about the size of the whole stuff.



second question: is it realistic to use a WiFi module with a basic battery like AA ?
I guess Xbee consumes less but requires an external antenna, afaik.


Any leads, advice, experiences would be very appreciate

Best,

[Reply #1 on:]

Your found box should be sufficient for your needs although it was originally designed for an Arduino with an Ethernet Shield.

is it realistic to use a WiFi module with a basic battery like AA ?

For a few minutes or for days? The former yes, the latter no.

I guess Xbee consumes less but requires an external antenna, afaik.

Yes, they consume less and no, they exist in versions without external antenna. But you have to install another Xbee on the receiving side and connect it to your PC somehow (probably with another Arduino).
A cheaper and often even less power consuming alternative is Bluetooth. Most notebooks already include a Bluetooth module so the reception side is not a problem and the Arduino side is not more complicated than an XBee (ZigBee to be correct, XBee is a form factor nowadays) solution.

[Reply #2 on:]

Thanks a lot for your answer.

Problem of Bluetooth is the distance.
I'll use it with a distance of 10m to 20m (20 is a real maximum)

Problem of WiFi (even with sleep mode when the device doesn't move) is the consumption


I guess this one would be more realistic :

On the remote side
Arduino + Accelerometer (wake-on-shake friendly like this one) + Xbee/ZigBee with a shield

On the computer side
Xbee Explorer  + Xbee/ZigBee

I guess I'd have to use an Arduino Nano in order to reduce consumption too.

Put everything in a (cute) box will be a challenge for me too :p

[Reply #3 on:]

I guess I'd have to use an Arduino Nano in order to reduce consumption too.

Why do you expect a Nano to consume less than for example a Duemillanove? It uses almost exactly the same components just in another size factor.

[Reply #4 on:]

With the XBee Explorer module, I guess I can use directly a ZigBee module and the computer will be able to read/send message through that.

I didn't test Bluetooth over 5m. I know there are 2 power categories in specifications.
Maybe I'm already targeting ZigBee stuff. That seems more okay about distances required.


About Nano, you are just right. I read too fast.
http://arduino.cc/en/Main/ArduinoBoardFio can be the good one.
Containing connector for Polymer Lithium Ion like batteries + it contains the XBee socket at the bottom.




Anyway, I guess I'll go with Arduino Board Fio + ZigBee module + Accelerometer + Polymer Lithium Ion like battery on the remote side, and Xbee explorer USB + Zigbee with an antenna on the computer side.

The Polymer Lithium Ion like battery can also be charged using the USB connection on the Arduino Fio...

That seems to match well my needs.
Thanks for your precious advices here. Continuing to be interested by your opinion, of course