Drone fell off the sky switching from takeoff to land mode

ArduCopter
1

Hardware:

  • Cube Orange + Kore carrier board

  • Here4 GPS/Compass (DroneCAN)

  • Herelink telemetry

  • ArduCopter v4.5.7

  • Frame: Quad X

I sent drone from qgc (from cubepilot herelink controller unit) to takeoff to about 5 meters it held perfecly. then I switched it into land mode (using transmitter - herelink controller unit) and it just fell off.
After observing the drone the power cable of one of the esc’s were cut (not entirely) and I don’t know if the drone fell off because the wire was cut or wire got cut because drone fell off by itself.
Is there any way to see that kind of information from logs. I’m uploading the logs file

2

It looks like you picked Land mode then almost immediately picked Stabilise mode. Altitude was relatively stable for a time then you moved the throttle to minimum and Stabilse mode obeyed the best way it knows how (motors to minimum, fall like a rock) - there was even a blip of throttle but not held long enough to have an effect before throttle went to minimum and altitude continued to decrease rapidly.
Logging and everything stops with impact - the battery became disconnected.

image
image1687×839 16 KB

One major issue - no battery voltage, current logging or failsafes - SUPER-IMPORTANT !
One minor issue - motor outputs indicate a significant weight imbalance towards the front, the weight could have even shifted near the end of the flight.

EDIT:
Set these for the Kore carrier:
BATT_MONITOR,4
reboot, then:

BATT_AMP_OFFSET,0.37
BATT_AMP_PERVLT,50
BATT_FS_CRT_ACT,1
BATT_FS_LOW_ACT,2
BATT_VOLT_MULT,15.26195

What battery pack have you got exactly? 6S, 12S ? Li Ion or LiPo, SS, HV ?

3

I currently use 6s HV, thanks.

4

HV what? there’s HV LiPo’s, LiPoSSHV and LiIonSSHV ??
It’s just too confusing these days and we cant guess.

For 6S LiPo HV use these settings:

BATT_ARM_VOLT,22.10
BATT_CRT_VOLT,21.00
BATT_LOW_VOLT,21.60
MOT_BAT_VOLT_MAX,26.10
MOT_BAT_VOLT_MIN,19.80

If you get unexpected failsafes then fix the problem (bad battery, bad charger) but DO NOT change these values.

2 Likes