how to integrate the angle rate of gyroscope L3G4200D

qiuqiuaaa

The demo code can only get the angle rate, but I want to integrate the value to get angle. How can I integrate the discrete values? And I also have the same problem to get position information from acceleration. Anyone can help me? Thanks. (I use BS2)

ratronic

qiuqiuaa I do not have a working BS2 at the moment but you can integrate the axis readings by adding each sequential axis reading to a variable at consistent timing such as in a DO/LOOP that does the same exact thing every time thru the loop.

SRLM

While you could, in theory, add the readings together and get an answer, there are some things to keep in mind:
1. You must have a constant delta-t (sample time) in order to get a reliable answer
2. You'll have to scale your answer if you want it in terms of real units

And, most importantly:
3. You will not get valid results with this method for any sample period longer than a few seconds. The sensors (gyros and accelerometers) are just too noisy. Do a search for IMU and Kalman filtering to see why.

And now, a slight modification: if you're very careful, you might get decent results with the accelerometer for short paths (20 feet or so). There was a forum post about it a while back, possibly even in this search:

accelerometer integrate position site:forums.parallax.com

qiuqiuaaa

Thanks. I will try.