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Oct 05, 2019, 10:54 PM
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Obviously, I was curious to see what happens with higher filter value...
BF 3.5.5 Filters: Both D-term and Gyro 85.

With 50, harder to keep it level, as it was bobbing up and down. On 85 seems easier. Could be just perception.

Hover ~50 sec. Front Right and Rear Left motors are scalding hot. Like you can't touch for 0.1 sec. Blowing blowing.. flashlight, checking windings and all motor screws.. none protrude from base, let alone windings 2mm higher.

I only have single 1000uF lowESR on this 6s.
All frame/arm screws are super-tight.

Like 5min later, FR and RL are still warm. I guess 10 sec test hover next time.
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Oct 05, 2019, 11:28 PM
more speed and less weigh
Iím surprised the mamba f7 even runs properly on 3.5... and reason for running such old firmware ?
Oct 06, 2019, 01:38 AM
Registered User
Flashed BF 4.05

Setup receiver, OSD, enable GPS. Defaults.

Filter defaults were a joke (ie 150Hz dynamic etc). Thing jumped off the ground and almost made it into the sink. premonition ?

btw log analysis sais my motor oscillations are like 140Hz or something like that

*** try #2 ***
set min cutoff for d-term and gyro to 40. No good, logs show motor oscillating

*** try #3 ***
also set the filter2 to low 60.

*** try #4 ***
static BQUAD for both and 40. I'm hovering and not peeing in horror. But logs still show motors oscillating.
They are not scorching hot...

Am I even going in the right direction with this??
the log file the 10cm off ground hover is from ~30sec to ~50sec.

late but gonna lower PIDs.. D from 35/38 to 25/28.. or even 15/18. Its 10" frame and 9x4.5x3.
I did Radio Calib. I also tested each motor without prop. the worst motor registered a max of 0.03 on the accel.
.5mm x1 mm corner of 1 prop tip is bent
Im tempted to try different or 2nd 1000uF low-esr cap... ugh sleep... ugh
Last edited by romangpro; Oct 06, 2019 at 01:47 AM.
Oct 08, 2019, 09:54 AM
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hi hb hb
Oct 08, 2019, 11:15 AM
Registered User

Really hard to take off and drone is always trying to flip or drift

Here I am really struggling with my new build .This drone just could not lift off when it does it tries to flip backwards and even if it manages to lift off with much difficulties then It will wiggle and drift so quick that I have to disarm drone in mid air to save it .

In last flight I used black box to store data .
I am not really good in reading data off from black box but I am suspecting motor 1 is cause for this chaos .Currently I don't have a spare motor to test it so I am turning for help from community to check what is wrong with my build .

black box file -

black box in youtube-

realWorldTest1 (1 min 21 sec)
Last edited by nayan; Oct 08, 2019 at 12:24 PM.
Oct 11, 2019, 08:31 PM
Registered User
Just a quick update.
Cause of problem is mainly BF 4+ too aggressive filters and Wires bunched up pressing on FC transmitting bad vibes. Thats why didnt happen before.

Much less problem with 2blade props. I also put tape anti-vibration under motors. After 16min of flying, barely hand temp.

Gonna try the RPM filtering
Oct 19, 2019, 02:41 PM
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Motor Stutter

Hello all, hoping someone can confirm my understanding of what is causing my motor stutter problem. I can hear it while flying and see it in my video.

In the attached screen shot, you can see a 32msec blip in the RCCommand channel on the roll axis. These little spikes appear 4 or 5 times during the flight and always look the same. Mostly rolling right, but occasionally rolling left. Always about the same degree, and always when initiating with some roll.

My interpretation is that since the command has been given, and the gyros are indicating the quad motors did respond, and the PIDS dampened it that it must be a problem with the pot on my transmitter stick? Maybe some dust in there? I assume that if the RCCommand is reporting stick movement that it must have gotten that signal from the transmitter right? Not likely a glitch in my receiver on the quad?

Appreciate any help!
Oct 23, 2019, 11:23 PM
Registered User

I think my gyro is toast????

I have been trying to find out if it is something mechanical and there is nothing i can see. pulled it apart and put it back together. IDK. Just wondering if someone who knows better than I would can take a look and tell me if my gyro is bad. The pitch axis only is extremely noisy and i cant figure it out........
Oct 25, 2019, 04:47 AM
Registered User
Doesn't look too bad. Frame resonance around 260Hz, but not too bad.
Raw gyro data look totally fine.
Lot's of D-Term oscillations though on pitch. Try lowering P/D uniformly, maybe D-Min too. And add more filtering.
D=57 and dmin = 33 is obviously too high for your setup.
Last edited by gorro; Oct 25, 2019 at 05:13 AM.

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