WO summers ago, I worked for Professor Jim Ostrowski at the University of Pennsylvania. I built "DAX", the Dual-AXis rotation sensor. It measures rotation along two axes using analog integration of electronic gyroscope data, along with digital feedback and signal processing to compensate for drifts. It provides a rather accurate and stable measurement of rotation, and it is fairly compact and has a nifty user interface. I also built the DAX-DCU, Data Collection Unit, which is a tiny plug-in device which records data from the DAX during test runs, and allows you to download the data later to a computer for examination and processing.
he DAX board is pictured above, and the DCU is below. If you wish, you may download the final report with all the technical details, or peruse the Scenix SX assembly source code.