Strange pulsing from motors on 550 when hovering

[ChopperAddict]

Hi

I have finally managed to get my recalcitrant Flamewheel 550 into the air, and even setup the GPS in the middle of a pretty windy field this afternoon. So far, great !!

My Go Pro video was really wavy, so came home to work on the mount, and then flew it in a calmer area later this afternoon, only to find that the quad is not just adjusting power to maintain a nice level flight, which it does reasonably well, but every few seconds it is applying power to apparently random motors, causing it to tilt sideways, or forward, backward and even yawing, all totally by itself.

I don't believe this jerking is a gain problem, which I have set 150% on the 4 main axis, and I have atti gain set to 160% ?

I have a full set of DJI Opto 30A esc's on board, both the GPS and the IOC stuff is setting up correctly (according to the lights anyway), fully charged lipo with plenty of Oooomph in it to climb, but it makes me very nervous when it "jerks" in the sky in all directions for no apparent reason. When under climbing power, it doesn't seem to do this according to my last video, but as soon as I return to hovering off it goes again.

I have full GPS lock ( single flashing green, flashing yellow/green in Home lock, and single flashing green on Course lock)

Anyone got any suggestions as to why it should start doing this, as it didn't do so on it's GPS setup flight earlier today, in windier conditions. I repeat, it is not as if it is making the normal minor corrections to maintain atti or GPS modes, which you can usually hear, but these are significant additional pulses of power to motors that have no need of it as the hex is already nice and level, and there were no real wind gusts at all to effect it.

FYI I am using Naza M system and JR DSX9 radio, AR9000 Rx. I also have my GPS mounted on top of the NAZA controller ? Hex is well balanced.

Thanks
Ian

 

[OneStopRC]

In your GPS settings, the red area is a positive number and the green is negative.

If your GPS antenna is lets say center to your craft, you would enter something like this..

X = 0
Y = 0
z = -5 or the height to the top of the GPS from the CG.

See if this helps you, you may also have gain issues, please post your gains and pictures of your F550 if possible.

 

[ChopperAddict]

Hi OnestopRC
Attached are relevant images of my hex and all pages of assistant.

View attachment 16290

View attachment 16290

View attachment 16291

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I look forward greatly to your comments on this setup ?

Best
Ian

 

[Tahoe Ed]

Your GPS is not at 0 on the X axis. Your aileron is not centered green. My guess is that you COG is lower than the top plate. Hang this from a motor with the lipos and camera attached. I would check your settings, recalibrate your Tx and do the advanced calibration on your IMU and then calibrate the compass when you get to your flying field.

 

[tahoejmfc]

Can you please video and upload a flight so we can determine the problem?

 

[ChopperAddict]

Interesting comments - thanks


I am a little confused as to how to get the aileron centered ? I have them set at +/- 100% and cannot use sub trims or normal trims, or it will not initialize, I get constant flickering yellow of the MU when I do this. How can I center an axis that does not center automatically when I click "finish" ?

I also noticed that I had to fly with right aileron applied all the time in the 2 recent test flights, no doubt due to that failure to be centered ?

I will certainly double check my COG calculation, but it ain't that easy to get it right on the Z axis accurately.

Also, and just to be dead awkward, right now it refuses to initialize at all, I get CFG-ERR[8] on Assistant, and a constant red flashing on the MU when not connected to the assistant. Whatever I do it refuses to go away ????? Tried restarting radio and powering up Hex, no difference, cannot do stick centering due to the ERR. Well stuck really.

SCRATCH the above paragraph, I suddenly realized the best way to fix that was to import a previous (working) setup, and it did.

Have changed GPS settings to -4, 0 -6, which must be pretty close. I sure didn't see that it was actually forward of the true COG, so thanks for that.

Problems, problems.....
Solutions ????????
Ian

tahoemfc: Will do as soon as i can get it into the air again.............. :-((

 

[bensid54]

I have had an issue with my 550 and Naza light controller which I am gradually getting cured, so far I have my gains set at 210 for pitch and roll on the top setting. The attitude is set at 200 for pitch and roll so far but that is still needing fine tuning my yaw is higher too but I forget the setting at the moment. I'm also finding my batteries are lasting longer the better my gains are set.

 

[hjls3]

if you are geting twitching i would double check the bullet connectors between motor and ESCs