Which micro controller would be suitable? (camera/wifi/PIR sensor)

[mastermaw]

Hello all, I need some recommendations for microcontrollers. The project is a small security device, running on a single AA or button cell.

A PIR sensor detects motion, which latches a relay, turning on a camera and WiFi.

The camera takes a picture, saves it to storage and then emails the picture via SMTP to a preset recipient and deletes the image.

Of course to conserve power the cam and wifi are always turned off unless motion is detected. Clearly a small button cell wouldn't last long powering wifi!

So, I need a microcontroller with very low consumption, at least 1mb of onboard storage, a CPU capable of processing an image and firing off an email within 10 seconds, and reasonably simple connectivity with a WiFi chip and camera.

Ideally, all the components should ultimately be available for under $40 - but for my project, it's not an issue. The components should also ideally fit in a 5cm2 box - but for a prototype, size isn't a problem.

I know similar security devices exist but this is a fun project for me. The crucial thing here is that the device can run on a small battery - AA or perhaps a button cell. In which case, might it be sensible to have the PIR+controller separate to the cam/wifi controller?

Does a suitable microcontroller spring to mind? I've played with arduinos but find the various shields a little clumsy and thought better options might exist. There are so many Atmel and TI options out there, it's a bit bewildering.

Any advice much appreciated!
Thanks.
Maw.

[nctnico]

If you are going for low power then the MSP430 from TI is the best choice. The MSP430 has been specifically designed for low power from the start.

[eliocor]

are you sure regarding power requirements of your PIR sensor?
To my knowledge they typically require from 0.5mA to 2-3mA (some rarer devices require only 100uA).
I'm not so sure how long your battery will last (sensor must always be on)...