Crash during switching from mission to manual

🧪 Flight Testing & Log Analysis
1

Hi all,

I have tarot 650 mm with Holybro Pixhawk 4, running PX4 1.12.2
Hacker a40 1000kv motors with 13x8 props and 3s 10000 mah battery.

The drone was in mission mode and when i switched to manual to take control it immediately flipped and crashed.

I’m not sure why, and ill appreciate any help trying to understand what happen.

The log files:
crash logs

Thanks,
Iftach.

2 Likes
2

Hi @iftahnaf ,

Sorry to hear about your crash.
The drone went into a freefall when switching to manual because the throttle stick was at zero. At zero thrust and without airmode enabled, the drone cannot hold its attitude, this is why it flipped.
Remember to always keep the throttle stick centered when flying in auto mode to avoid this problem in case you need to switch to manual at some point.

DeepinScreenshot_select-area_20211027112811
DeepinScreenshot_select-area_202110271128112050×615 73.1 KB

2 Likes
3

Hi @bresch,

Thanks alot for the answer.

I though that switching to manual with zero thrust was the main reason, but I still have some uncertainties:

  1. 0.2 [sec] after the switching I pushed the throttle stick up but it didn’t help to stable the drone, is this was too late? maybe entering to manual mode while still in RTL maneuver with zero thrust was too difficult to handle for the controller?

  2. The output of motor number 3 after increasing the throttle was at pick of 1950 PWM, it doesn’t feel reasonable right?

bokeh_plot
bokeh_plot840×336 39.5 KB

Thanks again,
Iftach.