Motors cut out mid-flight

PX4 Autopilot
1

During PID parameter tuning, the drone was hovering roughly 1 to 2 meters above the ground when the motors cut out mid-flight, causing it to crash. Post-crash inspection confirmed the power system functions normally, and the vehicle can be re-armed and take off again. PX4 control outputs checked out fine, with no critical fault logs reported prior to the motor shutdown. Does anyone have any idea what might be the root cause?

I’m sharing the log on her:Flight Review - Quadrotor

Notes

Firmware version: v1.16

Hardware: Pixhawk 6C Mini

External sensors: GPS only

2

This is a custom firmware? What has changed? Is the test indoors? Your mag doesnt seem good.

3

Based on PX4 Firmware v1.16.0, DDS data transmission has been integrated, with the maximum horizontal and vertical velocity limits adjusted accordingly.

4

First fix your mag problem. See if it helps. Re-calibrate your FCU and/or or be away from magnetic fields.

5

Thank you for your suggestions.

6

Hi,
Inspect the mechanical parts.
I’ve seen a similar problem: the VTOL hover then motors cutoff. After inspection the FC I’ve seen a small solder ball on it. Fortunately remove it solve the issue.

7

Thanks for sharing your experience. Was the solder residue you found on the flight controller PCB or the ESC?

8

You are right to ask this. I don’t remember exactly, but it seems it was the power distribution board, near the two battery cables. My colleague used a too higher temperature than necessary, which caused splatter of solder balls. Check all the PCBs you’ve soldered with a magnifying glass; that will eliminate an easy cause.

9

Hardware or software? It’s probably going to be a process of elimination. Let us know when you find the problem.

10

Thank you for your suggestions.

11

We enabled bidirectional Dshot to monitor motor RPM and found that the ESC cuts out first. The aircraft shuts down abruptly after running for 1–2 minutes each cycle. We have confirmed the fault originates from the ESC, and the ESC manufacturer is currently investigating the root cause.

12

Is the problem with all ESCs or just one.

13

The problem only just one.