I have compared ( with plots ) xgyro / ygyro with rollspeed / pitchspeed and found them to be quite different in that rollspeed / pitchspeed have a very large amount of noise that pretty much overwhelms the ability to see the underlying rate. The noise is several hundred percent more than the rate signal. However, xgyro / ygyro seem very clean and it is easy to see the rate data. I am not quite sure if these angular rates are in a different reference system but I question the noisiness of rollspeed / pitchspeed. The data that I am looking at is simply from holding the APM 2.5 in my hands and slowly and smoothly rotating it about an axis. Is something wrong or is this to be expected? Can someone explain the differences? I enclose my tlog files for reference. Thanks in advance
You need to be a member of diydrones to add comments!
Replies
I think I might be able to answer the question myself - I noticed that the Mission Planner tlog sample rate of xgyro and ygyro is only 2 times per second whereas the rollspeed/pitchspeed pair is 10 times per second. Noise on the signals which is high frequency would be missed by the slow sampling of raw_imu (xgyro/ygyro) signals.