Good afternoon, sir.
Let me introduce myself, my name is Firman, a Pixhawk 2.4.6 user.
I experienced a very bad incident with my mapping aircraft. It failed the mission. However, I’m confused and don’t know for sure what caused my aircraft to crash so badly.
Damaged components.
Runcam 4 camera
Sonny A5100 camera
6s 10,000mAh battery
body
incident:
The aircraft took off in FBWA mode and immediately switched to auto to complete the mission.
The problem I’m still not aware of is that while heading to waypoint 7, the aircraft suddenly descended rapidly from an altitude of 100m. My battery sensor wasn’t calibrated accurately. The battery was fully charged at 25V, but the indicator showed 23V. I don’t think there was a problem with the battery.
Please help me learn from my next mission.
I’ve attached the log data below.
Thank you in advance.
From the logs it looks like your drone breached the fence alt (FAILSAFE_FENCE-1 error message) and this triggered RTL after switching to auto mode again. This seems to have happened a lot of times during the flight.
Yes your battery voltage reading was very low for a 6S but in any case your battery failsafe is not correctly set for 6S BATT_LOW_VOLT14,4 should be more 22 or 23V. And the current reading is not set (if you have a current sensor)
Anyway your altitude reading is never more than 110m and your fence max alt is 130m… so idk why it triggered
What version of ardupilot are you using ?
the RTL i guess come from GCS FS not from fence as the altitude never break that limit, in the end (when it dive) the FC give command to Elevator to UP but the Plane keep diving
Servo problem or linkage ?
or what the end of your waypoint can you Screen shoot it ?
for Firmware Version V4.5.3
Sorry sir, I have already said that my battery indicator does not display accurately, because I tried several times and failed to set the power section of the Pixhawk module.
Not a cause of the problem but you should update to the latest Stable or Beta version of firmware so you don’t get the “sending unknown…” spam messages.
And, fmuv2 is really not the right firmware for that board even if it’s an old 2.4.6. fmuv3 or Pixhawk1 is or Pixhawk1-1M if it’s a 1Mb board.
No, but it can effect the compass. Again, I don’t think this is the cause of the crash but you have the Flight Controllers internal compass as primary and the external as secondary, the opposite of what you want. In a Plane the internal compass can often work OK but in your cause it’s being effected. This is the tool we use to see that:
Re-order the compass priority. And you should use Magfit to calibrate the compass(s).
Note-I’m not the best at diagnosing a Plane event unless it’s a VTOL involving motors (like a multirotor). So, I’ll leave that to others. What I’m suggesting here is just good common practice.
In red is your plane desired pitch, in green your actual pitch and in blue the altitude.
You can see that the plane couldn’t achieve the desired pitch anymore.
So it may be a servo problem.
I think the fault that caused the plane to fail to take off was caused by the electromagnetic field from the battery cable to the motor.
Thank you for your input, sir.
