Please Help Log Crush

Cube Autopilot
1

Hi Everyone

I been having the same problems with my drones. The problem is always the same, normal flying, and then, the drone start do go down, not very fast, but fast enought tho damadge it. No matter what I do to try to go the drone UP, keep falling.

After the crush, I turn it on, and all system are normals…

Pls I really need you help

I have change the ESC for another brand, thinking may be was the problem, but the same. This is the 4 or 6 drone with the same behavor. Im looking the logs, but I really cant find the problem…

This flight took almost 15 seconds… then start to fail… In the flight you will see I was moving the drone right to left, that was a deliver movement. Meanwhile I was doing that, the drone start to fall. As soon as the drone start to fall, I change to Stabilize and full throttle (i was in loiter FM), but no change, any way the drone fall.

Before that, i was flying for 30 minutes, doing the same, and no problem, I just change the battery and start over again.

this is the log
https://ufile.io/z29qapm4

PLs I really need your help!

@philip, pls, can you check my log?? I really appreciate it.

Im using Pixhawk 2.1 Cube

2

First, we look at what the drone is trying to do. Here is climb rate, desired climb rate, and total throttle output:

image
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From this, we can tell:

  • The drone knows that it is falling and it wants to ascend
  • It cannot ascend because it is at maximum throttle

Now, we try to see why it was at maximum throttle. What were the motors doing? Here are the roll, pitch, and yaw rate outputs:

image
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Here, we can see that when the drone was trying very hard to roll to the right (ROut is positive). This might mean that a motor on the left side has failed. Let’s check the motor outputs:

image
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Motor 2 and motor 6 are at full power, and motor 5 is at 0%. This probably means that either motor 2 or 6 failed.

You say that this always happens after you fly for a short time? What motors, ESCs, and propellers are you using? If you use the wrong combination, you may be overheating your motors or propellers, which can cause this type of failure reliably.

3

Thanks for your help!

Im using: Arris 4010 380KV Motors
15x55 props
20000 mah 6S battery
FlyColor ESC 35Amp (every motor can take 16Amp max, testes on my bench) BLHeli 32 bits, and the other accident I have I was using Arris Opto 30Amp ESC.

I Suppose the motors and ESC are not the problem, before this 15 second flyght, I did a 30 minute flight, reaching 100 meters altitude, and stressing the drone. After the long flyght, the drone was stady for 10 minutos aprox, so the motors were already cold for a 15 sec flight at 6 metter.

I use this same drone yesterday, I flew for almost 1:30 hours, with no brake, and no problem.

Coud be an energy problem? Im thinking maybe the user didnt plug the complete XT90 plug, just the tip or part of it?