Grumman-581 wrote:
The accelerometer / gyro systems that I've seen so far with rs232
outputs go for around $1K-$2K...

You can get a 3-axis accelerometer with analog output for around $300.
I recently used one like this
http://www.xbow.com/Products/product...s.aspx?sid=185 for a project
in a ground vehicle. I used a three-axis one that takes power and gives
you three analog outputs X, Y, Z. The same company also sells an RS232
A/D board but IMHO it's a little spendy at $300. If USB is OK I know
you can get small USB DAQ boxes from several different vendors. I was
using an older National Instruments full length ISA card, but then again
it was OK for me to have an entire desktop PC case in the back seat of
the car.

None of this stuff is official aviation stuff (nice aluminum box, round
connectors, etc) but then again it doesn't have an official aviation
price tag either.

Standard disclaimers apply; I don't get money from any of the companies
mentioned.

Matt Roberds