Slight crash during autotune


Second time posting here.  I am flying a 550mm hex, with pixhawk v2 on version 3.3.3.  I was performing an autotune using ch5 as my alt hold and ch8 for my autotune.  I believed to have my voltage moniter on 10.5v but somehow as the autotuning process went on forever, I ran my 6000mAh nanotech 3s down to 3.07v on one cell... the other two were a little higher.  I assume the battery entered failsafe mode and just cut power to my copter, but I am confused why my failsafe did not engage.  Was it because I was in the middle of autotune or is it this knock off power module?

Do you think the lipo is ok?  I went ahead and started to recharge it, and my iMax b6 is giving it a charge with no swelling or heating of the pack.  Would I have only reduced the life of the battery by doing this?

Also, how do I know if my PIDs for the autotune were saved or not?  I did not switch off ch8 before disconnecting power, but I did turn off the TX after it hit the ground because the rotors were still turning and it wouldnt respond to my stick input.  I assume because I panicked and still had it in alt hold.  How long does the autotune process take?  I had went through both pitch, roll, and partially through yaw when the battery gave out.  

My log file is over the 7mb limit.  How do I bypass that so someone can please help my answer all of these questions.

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  • Good Luck

  • Ok. I'll check my parameters again. It may be my hardware too. Thanks for taking time to look at this Cala.
  • Try tree axes again and check in MP- initial setup -battery monitor if it's correct your batt setup, your FC didn't detect that batt was empty.

  • Yeah I'm sure it's bc I didn't have enough power. I didn't know how long it would take to do the entire tune, so I was caught with my pants down. I'm more confused why my battery monitor didn't engage my RTL failsafe. Also if my PIDs were saved or if I have to auto tune all three axis again or what?
  • Probably you didn't have enought power, motor 2 stop and collapse, It's better to autotune one axe at a time if you don't have enought flying time, go to full params list in mission planner autotune axes and check what you want to tune first. you can look an older log and compare params if something change.


    here is my dataflash log of the flight.  Please let me know if this is accessible. 

    Shared with Dropbox
  • I know I've asked a lot of questions here, but I would also like to know why I have such significant Mag interference. 

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