Please help me diagnose this FPV/QAV250 hard turning behavior (video)

[02DropTopM3]

Guys,

I'm new to the 250 mini racing quad scene so I was hoping for a little tuning help.

I'm running a Naze32 flight controller and am trying to get it all dialed in. I went out today and did some high speed laps around a soccer field in Acro mode. There was a slight cross wind but the quad was very stable. However, when I was turning hard around the goals there were several times (3 laps in a row in fact) where at the end of the hard turn the quad would stop tracking through the turn and would 'slide out' of the turn (for lack of a better description).

I posted the following video showing the 3 instances of this behavior back to back. The specific behavior I'm talking about can be seen at 0:05, 0:12, and 0:18 in this short video:

QAV250 High Speed Turns (0 min 21 sec)

(Mobile Link)

QAV250 High Speed Turns (0 min 21 sec)

For all you pro's out there, is this something that can be tuned out using PIDs on the Naze32, or am I just approaching the turn wrong? Pulling too hard? Slight tailwind in the turn causing me problems?

Any ideas are welcome. Thanks!

Also, here's the full video of the flight if it helps at all, including the final crash

QAV250 Fast Acro (4 min 23 sec)

(Mobile Link)

QAV250 Fast Acro (4 min 23 sec)

[InFocus]

How much rudder are you using. I'm wondering if not enough, and thus it will fight you through the turn. To be honest though, I don't know if that would cause the behavior your seeing.

[02DropTopM3]

Originally Posted by InFocus

How much rudder are you using. I'm wondering if not enough, and thus it will fight you through the turn. To be honest though, I don't know if that would cause the behavior your seeing.

Hard to say. I'm keeping the rudder consistent through the turn (at least I think I am).

I'll try making some changes to the yaw PIDs to see if that changes the behavior.

[PTcaflyer]

...looks more like technique. I don't run that FC (run KK2.1.5W/ Steveis) and it looks to me like your gains are OK, just try a larger turn radius and keep your forward momentum...maybe a steeper bank angle too...

[02DropTopM3]

Originally Posted by PTcaflyer

...looks more like technique. I don't run that FC (run KK2.1.5W/ Steveis) and it looks to me like your gains are OK, just try a larger turn radius and keep your forward momentum...maybe a steeper bank angle too...

Yea, I went back today after reducing my yaw PID's. That was worse for sure. Increased them and while it felt more locked in, I was still sliding at the end of the turns, so I think where I originally had the gain was pretty good and I'm going back to those settings.

I think you're right that it's more of a technique problem. When I'm at speed like this I'm treating the quad like an airplane thinking that if I want to tighten the turn I can just pull back harder on the elevator. That doesn't so much work on a quad where you don't really have a wing.

I'll keep at it... Practice, practice, practice...

In reality, I have more fun trying to thread the needle through the trees and bushes and other obstacles anyway...

Thanks for your help.

[Diviner]

I had that problem sort of on my original KK2.1.5 settings.
A quad yaws by slowing down 2 diagonal motors and speeding up the other 2. At very high throttle, the controller gets confused on what to do 1) keep the speed up or 2) yaw. The controller sends out its signal to the esc to speed up but the esc's are already at full power, so bad things happen.

My problem has diminished due to upgraded the firmware and I have changed my flying style to complete the yaw before slamming the throttle to full. Plus I feather the throttle now rather than hammering it.

Also, more aggressive blades will take care of it.

I can't say if your problem was the same as mine as I haven't installed my naze32 yet.

The good news is that you are flying hard. This problem only happens to fast, agressive pilots.

This video talks about it.

https://www.youtube.com/watch?v=QjK0...wZ4E7D8ZgKIH9A

https://www.youtube.com/watch?v=0teg...wZ4E7D8ZgKIH9A

[02DropTopM3]

Originally Posted by Diviner

I had that problem sort of on my original KK2.1.5 settings.
A quad yaws by slowing down 2 diagonal motors and speeding up the other 2. At very high throttle, the controller gets confused on what to do 1) keep the speed up or 2) yaw. The controller sends out its signal to the esc to speed up but the esc's are already at full power, so bad things happen.

My problem has diminished due to upgraded the firmware and I have changed my flying style to complete the yaw before slamming the throttle to full. Plus I feather the throttle now rather than hammering it.

Also, more aggressive blades will take care of it.

I can't say if your problem was the same as mine as I haven't installed my naze32 yet.

The good news is that you are flying hard. This problem only happens to fast, agressive pilots.

This video talks about it.

Nice! Thanks for the links. Watching them now.

[Diviner]

If you are flying 5", then try 5x4x3's. Otherwise jump to 6x3 if you can.

I was flying fast today and had the same issue on 5x3 carbon composites.

[kayakboy69]

Sounds like some one needs to write some firmware that limits throttle imputs to 80percent but giving the quad 100percent to manage tight maneuvers at hi speed ..
Sorta like a gov on a heli ... but diffrent