Did the copter just die in the air and crash? It looks like logging just stopped. That could be an issue with a voltage regulator or battery connector.
Your vibrations are not high, there’s a bit of X/Y axis but nothing serious.
You dont need to change anything about the vibrations, and anyway it would be a hardware problem if there were significant vibrations.
There’s no harmonic notch filter data collected in this log, but I would assume from INS_GYRO_FILTER,75 that you have 5 inch props, and you have ESC RPM data so you could easily start with this for the harmonic notch filter:
INS_HNTCH_ENABLE,1
INS_HNTCH_MODE,3
INS_HNTCH_REF,1
INS_HNTCH_FREQ,80
INS_HNTCH_BW,20
INS_HNTCH_FM_RAT,1
INS_HNTCH_HMNCS,1
INS_HNTCH_OPTS,2
and see how it looks in logs with INS_RAW_LOG_OPT,9 set.
We need to see the next log to know more.
The battery voltage in that flight didnt go down to your low voltage level, so there was no failsafe action.
If you’re having trouble with the copter descending or losing control before failsafe triggers then ensure the voltage cutoff settings in the ESCs are disabled.
I can see where you selected Land mode and the copter landed the first time, the second time the copter was descending then you changed to Stabilise mode and flight continued. So that doesnt seem to be an issue yet.
The motor outputs are oscillating a lot because the copter has a lot of defaults and there’s no tuning done.
Start with these for 5"
ATC_ACC_P_MAX,162
ATC_ACC_R_MAX,162
ATC_ACC_Y_MAX,56
ATC_ANG_PIT_P,12.0
ATC_ANG_RLL_P,12.0
ATC_ANG_YAW_P,6.0
ATC_RAT_PIT_D,0.001
ATC_RAT_PIT_I,0.06
ATC_RAT_PIT_P,0.06
ATC_RAT_RLL_D,0.001
ATC_RAT_RLL_I,0.06
ATC_RAT_RLL_P,0.06
ATC_THR_MIX_MAN,0.5
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