Help for log analysis after some wobbles of my quad

Hardware Pixhawk family
1

Hi all,

I encounter some troubles with my quad. It flew very well before I changed the battery from 4S to 6S and the ESC from PWM to DSHOT

I’m able to take off, change throttle, move pitch, roll and yaw in good directions normaly and without any problem during about one minute or less. After, without any reason the copter falls down on a side and catches himself several times, in other words it goes up, goes down on a side and up etc. till I make an emergency landing

I’m wondering if it comes from an ESC desynchronization ?

May it be possible to get a more accurate reason by log analysis ?

If yes, could somebody help me to read and search in my log ?

Thanks a lot in advance !

Franck

Log : WeTransfer - Send Large Files & Share Photos Online - Up to 2GB Free

2

Try DSHOT300 or 600 and see if that is more reliable with your ESCs
MOT_PWM_TYPE,5 or 6
Some ESCs dont like DHSOT150

In the BLHELI settings (in the ESCs) make sure you have LOW RPM POWER PROTECT turned OFF

Use MissionPlanner motor test to verify prop rotation and motor positions, even run the motors for a while to verify reliability.

If you can set up a serial port to take the ESC Telemetry that would be handy, then you can have a better Harmonic Notch Filter config
INS_HNTCH_ENABLE,1
INS_HNTCH_MODE,3
INS_HNTCH_REF,1
INS_HNTCH_FREQ,80
INS_HNTCH_BW,40
INS_HNTCH_ATT,40

But set this anyway:
INS_LOG_BAT_MASK,1

3

Thanks for your reponse but my ESC can only manage up to DSHOT150

Ok, I’will look at low rpm power protect

I already verified prop rotation with MP and visual results were good. Motors turn smoothly in the right direction

Unfortunately my BLheli S don’t have any serial port

What do you think about demag compensation ? Maybe I should also activate it and add some low esr capacitor close to the ESC on the power supply ?

BR