Phantom 4 Not stable

[giorgimonk]

Hello, just bought phantom 4 and when i try to give it throttle one side seems to be struggling to keep up, it's left back motor and usually when all 3 motors stay on same level, left back motor and axis seems to be lower than all other 3 sides, tried swapping propellers, imu calibration, compass calibration etc... motor doesn't look like damaged at all, also i am not getting any errors or warnings any ideas??

 

[Fly Dawg]

motor doesn't look like damaged at all, also i am not getting any errors or warnings any ideas??

Try taking a look at your aircraft data file. The .dat from the aircraft. It supplies the motor and esc PWM data. You may be able to determine the issue from that. See the link below to get it. If you need assistance with reviewing the data, you will need to upload the .dat file to a sharable site ( Drop Box..etc...) and share a link to that back here and we can help you.

Retrieve a V3 Dat

 

[giorgimonk]

Here is flight log, i was flying really aggressively today because i wanted to see how it would react, also it was little bit windy
FLY876.DAT
also i see GeoPath ImuCalcs has signal ImuCalcs(0):Lat that isn't defined maybe that's the problem??

 

[Fly Dawg]

It does appear that the left rear is somewhat slower in RPM's than the other 3, however, in saying that it is difficult to make a definative statement on that due to your control commands. A much better test would be to allow the aircraft to hover for a bit with no control inputs. If that exhibits the same difference in motor speeds, then I would suggest that it a motor issue with the left back.

 

[giorgimonk]

It does appear that the left rear is somewhat slower in RPM's than the other 3, however, in saying that it is difficult to make a definative statement on that due to your control commands. A much better test would be to allow the aircraft to hover for a bit with no control inputs. If that exhibits the same difference in motor speeds, then I would suggest that it a motor issue with the left back.

View attachment 113500

Yes and it happens with quick ascending and descending , i have already replaced the motor, i am starting to think it has to do something with IMU, flight controller or ESC, maybe just firmware downgrade

 

[Fly Dawg]

ESC, maybe just firmware downgrade

The control signal for the left rear is also a bit low, so it is possible that it could be the ESC.

 

[giorgimonk]

The control signal for the left rear is also a bit low, so it is possible that it could be the ESC.

Yes might be, but i think it should be showing me the esc error ?? also when i open csvview log area it shows: GeoPath ImuCalcs has signal ImuCalcs(0):Lat that isn't defined

 

[Fly Dawg]

GeoPath ImuCalcs has signal ImuCalcs(0):Lat that isn't defined

Irrevalent. Those are related to the IMU and GPS computations.