large U8-135kV quad tunning,

running AC3.1 on a new large quad with U8-135kV and 29" props.

after lots of difficulties (autotune wasn't effective with that copter) I finally managed to get a flyable machine (under no wind condition).

still I am missing few tunning points for which I like to get your advises on what to do:

1) when descending fast it wobbles a bit. (motors are in general turning very slow! as you can almost see the props! -> what parameter shall I tune to get nice descend?

2) in windy condition the copter oscillate a bit and does not feel as solid as in now wind

-> what parameter shall I tune to solve this?

3) in stabilize (and therefore loiter), the altitude holding is crap with this machine. you can ear the motors like giving impulses instead of maintaining nicely the throttle like pilot is doing. you ear like no throttle then push then nothing and so on so the copter oscillate up and down and even sometimes (especially in loiter) tends to fly away!

tried to change throttle rates to 0.5 and 1 (instead of 0.75 and 1.5) but did not do the job!

-> what parameter shall I tune to solve this? this is my major issue so far.

I managed successfully to configure all my previous copters but this one is a pain!

attached a video (you can hear when I stay alt hold and stabilize...even if not as obvious as I would like to show it).

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  • It seems like help is hard to come by since this industry took off. Nothing but threads will no replies round here. Sadly this leads to a higher risk out in the field. Something this industry defiantly dosent need. Hope you get her sorted out nice ship!
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Shivchand Jaysaval liked Shivchand Jaysaval's profile
Aug 25