Again! I faced this issue so many times and everytime I smash my head against the wall. Let me write this down for posterity.
Here is a code snippet inspired from the ArduinoSleepCode that makes an Arduino wake up at night.
Following our research on rechargeable batteries and the meeting with Bartaku we ran experiments using a simple solar charger.
I tried to hack a pair of cheap (5 Euros) walkie-talkie that I bought in Paris. They work with 4 x 1.5V batteries (so 6V, but actually the batteries are kind of cheap so it makes 5V).
We were shopping the other day at St-Ouen's flea market and we bought two very effective motion detectors for 12 euros (yes, 12 euros for both of 'em!!!).
We opened them and found out they are actually pretty simple circuits. The plastic semi-transparent window in front is actually a decoy, which makes them look like infrared-based professional motion detectors. The truth is, the only active component seems to be nothing more than a photoresistor (!), most of the circuit being for playing different tones when a presence is detected.
Trying to cope up (somehow) with Sam's hyperactive work of the past few weeks, I started working on my own O/I-SO module. The plan is to build a small module with the following features:
I started implementing a small audio library for Arduino. It uses the PWM to generate different kinds of waves:
I built a small solar engine circuit from http://www.makezine.com. It basically accumulates energy from a solar panel (or another source) and once there's enough, it triggers a small motor.
I tried another program with the PIR, this time I worked on moving averages to compute the mean number of detections and the mean time people spend in front of the PIR. The goal is to use it to give to the object a deeper consciousness of its environment (ability to detect moments such as rush hours or very passing places).