Deacceralate a big quadcopter

I am using a quadcopter with 30 inch propeller and after tunning i found wobbling in braking due deacceleration from 10-15m/s to 0m/s while reaching next waypoint now i want to deaccelerate my quadcopter at a particular distance from next waypoint so can anyone help me out of this

Hello, welcome to the community.

How can we help you if you do not provide a .bin log file and the firmware version that you use?

Without the bin file we can only guess. One guess is that as your quad with big props approaches the waypoint and decelerates, a motor gets it’s lowest throttle signal and can’t go any slower. How much does your quad weigh? What voltage are you running? If you’re not running at least 30 to 40% throttle on the average, the drone might wobble when slowing and changing direction. We’ve made and flown quads and X8’s with 30 inch props, and if lightly loaded, have see this behavior. If you can provide the bin file we can quit guessing. Is it tuned properly? If you are running lightly loaded you can add some weight and see if that changes things, but if it’s something else you’ll risk crashing.

My quad weighs upto 15 kg and it’s propulsion system include
12s 22000mah battery
Mn8014 100kv motor from t-motor
T-motor flame 80a esc
T-motor g30*10.5 inch propeller also I will upload the bin file for the latest 10m/s flight

We use the firmware of arducopter 4.4.1

Still need a log file to assess performance.

Here I attached the bin file for the flight of 10.6m/s.


PSC_ACCZ_I,0.4    // always 2xPSC_ACCZ_P

You said T-Motor Flame ESCs, and these are the normal settings for them


You will need to recheck your MOT_SPIN_ARM and MOT_SPIN_MIN
If they are the new Flame ESCs that (some) claim to be able to calibrate, at the very least you still have the MOT_THST_EXPO too high - judging by past experience with Flames, and by the instability at certain throttle levels in the log.
You could try MOT_THST_EXPO,0.6 and see how it goes, but MOT_THST_EXPO,0.4 is normal for those.

Any significant change in MOT_THST_EXPO requires you to recheck your MOT_SPIN_ARM and MOT_SPIN_MIN at least, and maybe retune/autotune. (yes I’ve said that twice!)

How about the values of

Ignore them and don’t use Position Hold. It’s essentially deprecated and replaced by Loiter which is much more configurable.

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