I was testing my huge new build quad-octo, the motors are powered by 4 6s 10000mah, and the Pixhawk and electronics by a 3s 5000mah.
I successfully did the compass dance and it flew for some 10 min in Stabilize, AltHold and Loiter.
I was pretty happy beside some sloppiness in Stab, for which I thought I would try to low a bit D, Alt Hold was extremely stable and in Loiter it showed a tendency to move in a circle which I am not sure it is because the GPS is mounted on the frame and gets interference, so I was planning to try move it or to mount it on a mast.
I downloaded the logs and it seemed to me the vibrations are perfectly in specs, DesRoll vs Roll and DesPitch vs Pitch follow each other pretty smoothly.
It came as a shock as I tried to Auto analyze the log
Log File C:/Program Files/Mission Planner/logs/OCTOROTOR/1/2015-10-02 12-41-35.log
Size (kb) 10621.4677734375
No of lines 142870
Firmware Version V3.2.1
Firmware Hash 36b405fb
Free Mem 0
Skipped Lines 0
Test: Autotune = UNKNOWN - No ATUN log data
Test: Balance/Twist = GOOD -
Test: Brownout = FAIL - Truncated Log? Ends while armed at altitude 7.75m
Test: Compass = FAIL - Large change in mag_field (52.11%)
Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = FAIL - ERR found: FS_BATT
Test: GPS = GOOD -
Test: IMU Mismatch = GOOD - (Mismatch: 0.68, WARN: 0.75, FAIL: 1.50)
Test: Parameters = GOOD -
Test: PM = FAIL - 62 slow loop lines found, max 14.50% on line 838
Test: Pitch/Roll = GOOD -
Test: Thrust = GOOD -
Test: VCC = GOOD -
As you can see it shows a
Brownout FAIL which for my understanding it should have resulted in a crash and I never noticed any fast drop of the octo. What could possibly be the cause of this? I still didn’t put the capacitors banks on before the ESCs, would this help?
Compass FAIL, could this be because of the GPS mounted directly on the frame?
FS_BATT fail - I disabled all failsafe, where does this come from?
plus from the logs and on the ground it seems to me the batteries still had some power left.
PM=fail ?? what is this?
I couldn’t find any explanation on these…
May please someone with a better understanding of the logs, shed some light for me?
I am now very scared to fly it again.
The link to the log below
Any assistance is, as usual, MUCH appreciated