hi all,
ya the application notes were quiet good at analog.com.
the rest of my research as regards using accelerometers to obtain position are fairly damning.
the errors that would occur using sensors in my price range would be far too high, as mentioned earlier from previous posts. (some research indicated that after 60s with a certain accelerometer with a 150hz sampling rate the errors incured could be round 40m)

therfore i am going to try to use either a an accelerometer or gyro ic to find direction and make my own sensor to obtain positioning.

if anyone is interested here are two of the reports i found regarding INS, they are quiet good
http://www.electronic-engineering.ch/study/ins/ins.html
http://www.mbeckler.org/coursework/2007-2008/senior_project_paper.pdf

thanks for the patience and help so far everyone! i will keep you updated and hopefully upload a completed project soon!

 

You can find some good papers if you google for "inertial navigation system error".

Maybe you could find a cheap quick-and-dirty way to make some ring laser gyros.