X8 coaxial, stops all top motors during flight, bottom continue to work

Hi , Iam using X8 coaxial system , power source is a 22000MaH battery 6s , using Mauch power cube with 200A Hall sensor , used two escs with same power source , the drone flies well up to 22V and suddenly top motors stop and the down motors will balance the drone . ALogs of the Top motors stopping ny help is appreciated

This log do not show up the problem you reported.

Are you sure you uploaded the right log?

As @BrunoBagarini said there’s no motor/ESC failure in this log.
Maybe draw or reproduce a diagram of your power wiring too.
What ESCs are they?

But this log does show you have a motor mount twist problem. Clockwise motors are working harder to counteract some physical yaw bias. If you fix that your harmonic notch filter can be set better and make more sense, not to mention the wasted battery power and motor overheads affecting attitude control.

This bandwidth value is too high, probably because you’ve had those twisted motor mounts the spread of frequencies is so great, you’ve been trying to filter that really wide bandwidth.

INS_HNTCH_BW,75
INS_HNTCH_FREQ,67

The REF value you had would prevent the filter from doing it’s job too.
Set these at least until there’s better data after fixing the motor mount twist issue

INS_HNTCH_BW,30
INS_HNTCH_FREQ,60
INS_HNTCH_FM_RAT,0.7
INS_HNTCH_REF,0.18
INS_LOG_BAT_OPT,4

Set these for some general cleanup

ATC_THR_MIX_MAN,0.5
BATT_ARM_VOLT,22.10
BATT_CRT_VOLT,21.00
BATT_LOW_VOLT,21.60
LOG_BITMASK,180222
LOG_REPLAY,0
PSC_ACCZ_I,0.5
PSC_ACCZ_P,0.25

When the ESC/power issue is sorted and these parameters are all checked against another test flight, then another Autotune would be benificial.

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Hi please go through this log , first flight i had a problem of motors stopping in mid air , later in the second flight i didn’t have this problem

Will try fixing the motor mount , then input these parameters and will revert back

If this is with a LiPo battery then it may be damaged or lower capacity now.
The voltage drops to near 19v when the critical voltage should be 21.0v
If the motors were stopping then it’s likely the ESC were stopping because of the critically low battery voltage.

It’sVITAL to use Initial Parameters calculator to set these correctly by selecting your cell count and chemistry. The values that are calculated are tried and true for LiPos.
If you dont get the expected flight time, then check your voltage sensor calibration - NEVER change the battery failsafe voltage values.

Many of the other parameter changes also apply.

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https://drive.google.com/file/d/1S3lVbY6N83FVI3lwN4NCM6EPwfNnJUY0/view?usp=drive_link
can you go through the log , this is yesterdays log and i had a first flight where i got problem of esc stopping motors in mid air later again i have flied the drone but didn’t have problem

iam using a MAUCH power cube with Hall sensor , i need to input the calibrated values from the sensor OEM , i hope this sensor is good , but the esc stopping in mid air annoying me

What ESCs are they?

The Mauch sensors are quite accurate and calibration is usually very accurate.

So if this keeps happening, The ESC low voltage cutout is happening because

  1. you have the low voltage and critical voltage values wrong and you are over-discharging the battery, making it worse with each flight
  2. your charger is not up to the job, but mostly see point 1

With most ESCs you can turn off the low voltage cutout, or set it very low. At least they will not interfere with flight then, but it means you really NEED to have your voltage monitoring and levels set correctly.

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Iam using F55pro 2 Esc , i cant do any esc low voltage cutoff as iam using only simple pwm signal to control the motors

You need to get to the BLHELI32 settings in the ESCs and set:

  • Low RPM Power Protect = OFF
  • Low Voltage Protection = OFF (rely on the flight controller battery settings)
  • Temperature Protection = 90
  • Motor Timing = Auto

You problem has been the ESCs are cutting out (as they should) because you are letting the battery voltage go too low.
Check and use the parameters I’ve specified.

It will be worth your time and effort to set up the telemetry data from those ESCs, even if you cant use DSHOT with them all.

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I thought of using telemetry but iam using orange cube so i cant use 8 motors D shot setup