I got speed wobbles - Fixed, and advice

[SirRexAlot]

I have been tweaking and tuning my scratchbuilt copter for a few months now and I never had it fly right. It hovered fine with out of the box settings, but when I gave it a little stick input to get it moving it would shake and wobble. The motors sounded like they were chirping. I thought maybe an esc was going out or hitting an overcurrent shutdown or something. But it didn't fall out of the sky and nothing came down hot.

I went so far as to write custom code to wire up my aux2 knob on my Tx to each of the PID settings, one at a time, so I could twiddle them on the fly and see what happened. No setting helped. Even when I had everything cranked down so far it would barely move, my copter would shake and bounce when it got some speed. It was a much faster wobble than too much P, and did not have a positive feedback loop where it got worse like way too much P will do. I tested that will all range of other settings and got to know how each of the settings affected flight. Nothing helped. I have the broken props to prove it.

So I sat down and started going through code line by line, making sure I knew exactly how everything worked. Then I stumbled upon this from the config.h file:

Code: Select all

      #define MMGYRO                         // Active Moving Average Function for Gyros
      #define MMGYROVECTORLENGHT 10          // Lenght of Moving Average Vector

It flies great now! I can't believe it was so simple. Just uncomment these two lines and pow! It looks like there was just too much noise from my gyro sensors and a rolling average smoothed it right out. I never found this in any of the documentation anywhere (outside the comments in code), so I thought if I made a good strong case it might get added to a FAQ or at least be searchable to help out the next guy. Thanks for reading.

[Hasi]

I had the same problem on my scratchbuilt quad. Was very stable on hover, but if I started flying forward it would shake like crazy. My solution was to change to the new PID controller in MW 2.3.