"HI there,

When you downgraded to 3.1.5, did you have to retune your PID parameters? I attempted my first test flight today after downgrading and the copter just lost balance and fell over. It was as though the Stabilise and Pitch/Roll Rate P values…"

"Fantastic - thank you very much!"

"I have to admit I am somewhat frustrated too.

I have been working on my first build for the last three months and I am still experiencing these problems, despite going to huge lengths to minimise vibrations (which I have now reduced to about 0.1g.)…"

"Hi there,

I just want to check: Have you already built a multirotor? If not I really recommend starting off small (no bigger than 450) and building a conventional one based on any of the many build blogs.

There are many surprising real world…"

"This is a very good question and I am curious myself. If I increase these I don't want a flyaway!"

"I tried Kyosho Zeal Gel but it didn't do much to reduce vibrations in my quadcopter.
I recommend the mounts from readymade3d.com. These use rubber dampening balls. My Z axis vibrations were reduced from 1.5g (!) to 0.1g. I was pretty amazed! See…"

"My craft has a very crisp response to input when in Stabilise mode, so it will be interesting to see how the ATC params affect it.
When you changed your Throttle acceleration P/I, did you increase or decrease the values? Mine are currently at 0.5…"

"You are absolutely right - I completely underestimated how involved this was! However I have learnt an incredible amount over the last few months. So far it has been a very long process of elimination.

I am curious as to the relation between the…"

"Update: I just checked my parameters...
ATC_ACCEL_RP_MAX is 0
ATC_RATE_RP_MAX is 18000"

"Hey there,
I made sure to remove the jumper for the external compass and calibrate it. I'll definitely look into those parameters you mention though.
Thanks!"

"I am experiencing the same problems with my HKPilot Mega 2.7 and AC3.2.1. Haven't yet tried downgrading to 3.1.5 but that is on the cards.

Interesting, the throttle pulsing problem only manifested after adding some weight which pushed my throttle…"

"One other thing... It would be good do a Default+IMU log which contains the accelerations from the sensors. Vibration from the motors may be fooling the FC.

Have you balanced the props and motors?"