PID tuning for 12" instead of 10" props

In general, what direction would PIDs be tuned when moving from 10x4.7" to 12x4.7" props on a mostly-standard ArduCopter?  When putting together my current FPV rig I found that I got more stable flight at lower throttle settings using the larger props, with the exception that any descent causes the copter to wobble like crazy.  I saw this same effect with the smaller props but it took a much more rapid rate of descent to trigger it.

Note - this is in STABILIZE mode, which is the only mode I'm willing to fly FPV in at this point. 

The copter doesn't seem to overbalance but it does wobble through 30 degrees or so whenever it descends, and in addition to making my video look like crap it's rather difficult to control.  I assume I need to adjust a PID value to deal with this; any suggestions on what to adjust?

 

thanks!

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –

Replies

  • Developer

    When I fly original ArduCopters made by jDrones. I always use or start with these values with bigger 880Kv and 12" props.

     

    Roll/Pitch

    P: 2.5

    I:0.015

    INT: 40

     

    Those values are really good starting point to fine tune your frame. (And we fly them a lot :) )

     

    jDrones, R/C UAVs and More....
    Manufacturer of ArduCopter frames and parts. Custom airframe manufacturing, Custom design services for all your R/C UAV needs
  • If it is quick oscillations you can decrease the Rate P value, if it is slow oscillations you can decrease the Stabilise P value. Remeber to adjust both the Roll and Pitch values :-)

    Friends of mine also went to 12" props and found exactly the same as you, and we reduced their Rate P values over 4 flights (small changes) and it now works very well again.

  • Hey dude, I could be wrong, but from what i understand, the wobbles on descent is the craft falling through its own prop wash/turbulence. I get it too, but not if I'm tracking forward at a decent rate. I've changed to the big props too, seems to not have to work so hard to stay up, quieter too.

This reply was deleted.

Activity

Santiago Perez liked Santiago Perez's profile
Saturday
More…