Learned something about gains Yesterday!

[bensid54]

I was tweaking the attitude and altitude gains of my Naza V2 in the wind yesterday. I was increasing the gains bit by bit, thinking I was improving the performance but I was so wrong. After the last attitude gain adjustment when my hex about thirty feet or ten metres off the ground it started to rock violently and I could not stop the rocking no matter what I did so I landed as fast as safely possible avoiding a crash. At that point I started to reduce the gains and one thing I found was the lower the altitude gains were set the better it held it's yaw and attitude. On a different but related topic I made some temporary light weight plastic landing gear that I held in place with zap straps on to the existing 550 Flame wheel landing gear. It dawned on me that the zap straps are the weakest link of the landing gear and will allow some movement on a hard landing or crash as mentioned above, the straps will be the first to break or give movement in those situations possibly saving other more costly parts, I posted two pictures of the temporary gear and zaps below.

 

[Fat Corgi]

What gains did you end up at?

 

[genesc]

Great idea on the landing gear.. Thanks for sharing.

Gene

 

[bensid54]

I haven't finished tuning it but I will post them when I'm done. The landing gear was a surprise to me on just how useful it was.

 

[Fat Corgi]

reduce the gains and one thing I found was the lower the altitude gains were set the better it held it's yaw and attitude.

I have just tried this and agree it does make a big difference.

 

[Benjamin Kenobi]

Same here. I'm a low gain man myself.

 

[Bowley]

Me too, I up'd my basic gains a while back, was pretty rock solid in pitch and roll in wind but not so good for yaw, was looking back at some old footage from when I had my gains low and the yaw was far more stable

 

[OneStopRC]

Why do them legs look like they are drywall? tell me they are not?

 

[Benjamin Kenobi]

They look like polystyrene to me.

 

[bensid54]

I think they are polystyrene, I used to work at a boat building company and they used that in the fiberglass hulls. The material is very porous and cuts much better than nylon.

 

[bensid54]

I've tweaked my settings but they didn't seem to improve so I reset the settings to default then adjusted them to half way between default and recommended settings for a Flamewheel 550 and DJI motors. A bit more tweaking and this is about best I have done, the gain numbers are basic pitch 152, basic roll 153, attitude pitch 142, attitude roll 143, yaw 125, vertical 115. The reason the roll is one less than the pitch is first off I found the forward and rear motor hotter than the others so that told me they were working harder and it still wasn't great in flight. Dropped the gain by one at a time and it made a big difference so that must mean I'm very close plus it is flying much better.

 

[Big Duke Six]

Another thing to try is to experiment with your height above/below CG setting (the Z Axis). I took great pains to precisely measure my vertical CG and set the Naza up accordingly, but as I zeroed in on the gains I would get a SERIOUS case of the wobbles. On a frustrated whim I tried changing the Z Axis measurement and lo and behold, it actually worked. Big quad flies like a charm now, even though the setting is way off where I thought it should be. Like I said, it was a big (4 kg) quad with 15" props so that may play into it, I don't know.

BD6

 

[bensid54]

That makes sense Big but how did you manage to do that? I've since decided to go back to quad as opposed to hex because it seems the Naza control unit is far more stable in a quad configuration, so I'll keep the hex around for spare parts.

 

[Big Duke Six]

That makes sense Big but how did you manage to do that? I've since decided to go back to quad as opposed to hex because it seems the Naza control unit is far more stable in a quad configuration, so I'll keep the hex around for spare parts.

Don't give up yet!! I haven't flown a hexa with the Naza, but try changing your Z-Axis setting first. Go into the Assistant, Configuration and Mounting. You'll find the X, Y and Z axis settings there for the IMU and the GPS. IIRC, the IMU was the one I changed but if it doesn't work, try changing the GPS too. Make sure your + and - settings for all those are correct too. I believe the Naza should fly your hexa just fine - don't give up!!

BD6

 

[bensid54]

I'm going to try that on the quad when I get it up and running. Another reason I'm going back to a quad is I'm building a UFO for Halloween and I want a stable platform. I've always ignored those settings so it looks like I better pay more attention to all the available adjustments and I will stash the hex for a later date.

Don't give up yet!! I haven't flown a hexa with the Naza, but try changing your Z-Axis setting first. Go into the Assistant, Configuration and Mounting. You'll find the X, Y and Z axis settings there for the IMU and the GPS. IIRC, the IMU was the one I changed but if it doesn't work, try changing the GPS too. Make sure your + and - settings for all those are correct too. I believe the Naza should fly your hexa just fine - don't give up!!

BD6