I need engineering/instrumentation help

I found this if you want to build one

http://www.repairfaq.org/filipg/RC/F_Altim.html

The only other things I came along were altimeter watches,  you might try looking at a aviation scarp yard.  You might be able to cannibalize enough parts from a planes altimeter to do what you want.

thanks man i appreciate it. i'm trying to do something for aTtitude, not aLtitude.

i'm thinking having a mass on a pendulum, somehow connected to some springs on piezoelectric sensor which reacts when the pendulum is off centre. but that's about as far as i've thought.. i have very limited knowledge with this stuff

if you're doing a pendulum, a much simpler solution is to make a variable resistor or potentiometer. The idea would be the pendulum would swing back and forth and the end of it with the weight would always be in contact with a metal strip with some resistance. One side of the strip is positive, one side is ground, and then you measure the voltage on the pendulum (which is also grounded)

the idea is that at center, voltage would be half. When it swings one way, the voltage will be almost full, and the other way will be almost no voltage. If you're using a micro controller with a AD port then you can easily program it to read the data you want.

use a very high resistance strip too, so that less current is drained from your source and it doesn't heat up a lot.

thanks man. what kinda accuracy can i get out of that?

for such a helpful post i have no idea about either of these things. im gona toss you some karma, what a nice guy.

A pendulum attached to a piezoelectric tube would give you 2d attitude sensing. I don't really know what attitude is, but i'm assuming its some kind of tilt. I'm sure a buoy could tilt in all directions, so this might be the way to go.

Yeah, it's tilt. It could be mounted on a gimble to get attitude in any direction. An absolute value should be sufficient