Hello there!
In the last couple of months I dedicated some of my spare time to an old dream to build a drone from scratch. It's a 3D printed drone, using Arduino and a LSM303 (accelerometer) + L3G4200D (gyro). The props are nylon 9'', 30A Mystery ESC's, 2212 930 kV motors.
Currently I'm trying to stabilize it's pitch using a PID algorithm. I've tried everything but I wasn't able to make it right. In order to debug what is happening I took two data samples from the sensor (images below) with the drone locked in a fixed position.
As I'm not experienced, I'm not sure if the values in these graphs are normal, but I think that the PID issue is related to the vibration of the sensor or the sensor itself. The second image shows that the pitch data, even filtered and locked, goes up and down by an amplitude of 8 degrees. Actually I think there is something wrong with this gyro itself: even when the motors are stoped (first image), the gyro reading oscilates by an amplitude of 3 deg/s, way above it's precision of 0.00875 deg/s.
Drone rendered in SolidWorks (colorful parts meant for bench tests only):
3D printed:
I just bought a MPU-6050 that a guy uses in his video, btw, excelent PID tutorial. The sensor should arrive in a couple of days, then I'll have exhausted all my possibilities to debug this thing.
I would be very glad if someone could shine a light on this problem :D.
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