Eliminating vibes (balance with QGS)

[bluuu]

I think that live telemetry in QGS will be a great tool for monitoring vibes and do balance for fotor and props.
We can use gyro and ACC graphs but ... what is acceptable range for values ? (I know, lower is better and 0 is "the best of the best" but unrealistic )
Future thing for develope QGS - "big red button" with balance option for acuiring data from gyro/acc sensors for balancing (or fusion of them). (something like motortest function in MultiWii)
Good idea ?

[bluuu]

any interesting in from dev team ?

I will be very usefull tool.

[Jdmagoo]

Hmm sounds interesting, I think this might be useful but how would you determine the cause of the vibrations, wouldn't it only display the overal vibrations of the ship and not the cause. I guess that might be useful but surely if one spends time balancing both the props and motors then this might become mute.

[Max]

I guess I'm not sure what you mean by the big red button...

Testing vibrations while running motors on a flat surface isn't very useful. The turbulence from the props will cause all sorts of shaking. Ground test are more useful on individual motors, when they can be held over an open area. Of course with the right rig, one could do it, but as Jd points out, that only gives you the overall vibration level, which can probably better be deduced from a flight anyway.

I'm generally seeing that if my accels have more than ~0.3 range of noise, then the AQ PIDs need to be tuned down to compensate. That's very general. Some vibes are more obvious on the XY and some on the Z. I haven't been able to make much use of the gyro plots, though I'm sure with more experience one can get useful info out of them.

Actually I have a good example for you... Here are 2 log graphs from the same Y6, same day. The difference is I switched props for the 2nd flight. Both sets were balanced in the same fashion, on their own, not dynamically on the motors. Tilt Rate D is 7180. The first flight was very smooth. The 2nd flight had very noticeable instability... the motors ran less evenly, and altitude was harder to maintain. Also very obvious by looking at the MOT_ROLL and PITCH graphs that the motors were working harder, with more speed variations and range. I cold probably tune it out by lowering TRD, but that's obviously not the best solution.

Smooth:

Rough:

Any questions?

HTH,
-Max

[bluuu]

Look, with this tool we can:
- ballance individual motors without props
- ballance props with external ballancer
- ballance individual motors with props

You can start for instans motor 1 and look on graph with gyro and acc noice, then you ballance this set.
Nex step, motor 2, and next and next

It can be usable after crash, after changing props etc.

[Max]

Start telemetry in QGC, go to the graph view, enable ACC/RATE plots. I'm honestly not understanding what else you need...

-Max

[bluuu]

Max: i need 1 more thing
Ability to enable one by one motor at a certain speed.
I know, I can do this by connecting to the esc32 but ... I must disconnect signal between FC and ESC, connect to esc by uart, use another PC to connect to FC and look at telemetry .... as you see it's difficult
Another possibility .... use RX to connect to esc ... but ... it's difficult to set the same values by stick (to compare results) and .... if I use esc32 I must reconfigure it to work with RX ....

I explained ?

[Max]

How about using a custom mixing table and enabling each motor port in turn? You could set throttle to, say, 50, then when testing just put your Tx stick all the way up. Consistent every time. Hmm, wonder why I haven't tried that before! New mix UI makes it easy, too.

I'm not saying that something to do it all for us wouldn't be nice... Plus I also want a dynamic balancing machine that tells me exactly where to put the damn weight just by spinning the motor/prop... (they do exist but $$$$)

-Max

[bluuu]

allright it's third solution
BUT:


Imagine the view of the screen where you have options:
- Engine number / port
- throttle (in %)
- Window of readings gyro and acc

Nice and simple and usefull ?

[Kisssys]