Adapting auduino code to take input from sensors

[Alejandro]

Hi,

I've made a bird out of clay, with in it 4 sensors: an emf detector, a
light dependent resistor, a thermistor and a "plant monitor" - that
checks for humidity. I've kept track of it at
http://tziteras.blogspot.com/2010/02/maker-faire-exhibit-weeks-3-and-4.html
and in previous posts on there, and as you can see, it's made the UK
maker faire.

The clay sculpture uses some adapted auduino code feeding in the
values from these 4 sensors in various ways, and some simple logic:
emf goes up if people are around the object, light goes down if
someone is messing with it or covers it's light sensor, so when those
values change it affects the parameters going into the audio synthesis
bit of the code.

I've got it waking up on direct sunlight and emitting some lovely
granular synthesis. The first tone it makes is determined by the heat
sensor, when people mess with it's electromagnetic field, it causes a
delay, giving the sounds a discernible beat, and when no-one is around
it also slows down until it's emitting quite sparse sounds. I'm adding
more as I think of them.

But I thought it worth asking here - has anyone played with automatic
calibration of the sensor inputs? Every day they are different and
throughout different seasons as well it'll pick up different things.
Each time my creation turns on it could create new calibration info,
maybe for example if it sometimes logged it's data to EEPROM and used
that when turning on again.

I'd be interested in reaching more of the "interesting" noises at the
extremes of the range as described on the auduino homepage, but I'm
not sure how to map the values I get to these interesting areas of
auduino frequency. Is there a good project to look at that might do
some of this already?

Thanks very much!

Ale