Problem t motor u8 lite 190kv in copter 3.5.3

Chassis construction own 1600mm exacopter…
Engines u8 lite 190kv.
Escs tmotor flame 70A lv
Pixhawk Cube 2.1
Batery 6s
After performing all the calibrations, everything is fine.
But when setting and accelerating in stabile mode the engines begin to tremble.
As if they were jerks.
I have to configure something related to escs in MP.
I would be very grateful if you could lend me a hand.
Thank you and sorry for my bad English.

If you can post a .bin file from the Pixhawk that would enable people to have a look at your configuration and the copters reaction s from the flight test.

Do not perform any flight, just test without propellers.
I did not dare take off with that ploblema in engines.
Will suffice with .log without taking off?
Video of armed in stabilized mode.
You see how the engines vibrate as if they are out of sync.

In this video all (motor test), it is seen as they do not vibrate and there is no desynchronization.

Here .log
2017-09-26 12-07-44.log (445.3 KB)
2017-09-26 12-32-52.log (307.5 KB)

Thank you

I dont thinks that it’s a problem of desync, but of unbalanced motor
I’m curious to know how perform this motor at 6s because the 170kv really didn’t work fine at this voltage

It is impossible for this motor to be unbalanced.
If you look at the first video does it and the second does not.
If I was unbalanced I would do it in all 2 videos.
In the .log I found this, I do not know if it will be related.
Test: Motor Balance = FAIL - Motor channel averages = [1337, 1444, 1280, 1473, 1450, 1329]
Average motor output = 1385.
Thank you.

At different speeds the motor can vibrate. higher voltage , higher speed. I use Hamm seismograph app on my phone to help balance my motors. The motor test will fail without props. reason being that the copter tries to level , but cant without props. strap your machine down with props on. Dont know if you use BLheli on your escs. the dithering setting helps with with vibrations at resonation. I have the same motors on 6 cell without problems by the way.

I use Tmotor tmotor flame 70A LV. (They do not have any type of configuration)
If I did not misunderstand, you mean that the vibrations are produced in the flight mode stabilized by the engine corrections without having propellers.
However if I use the test engine does not vibrate, so the motors are well balanced.
I will do a test.
Thank you

I flash blheli onto all my escs. it sounds almost like motor timing issues. but it can also be that your escs are trying to brake the speed on your motors without load on them. install your props and strap it down. arm in stabalize and raise your throttle just a little bit. see if the vibration persists.

Why do You think are the most BIG rigs with low KV motors such as 170 kV or lower are being flown with 12s ???
The counter-torque of big props combined with low kV motors is much too high on 6s to work well on fast reacting
FCs and ESCs. Unless You just wont to hover in no wind situations.

Just my 2 cents.

regards, Christoph

The reason the motors were “trembling” in the first video is because Pixhawk thought the aircraft was in the air and was trying to get the aircraft level. This sort of bench testing is totally useless.

The motors did not tremble in the second video because Pixhawk was sending a fixed PWM value.

You need to put the props on and fly it.

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