AQ Motor outputs show large swing (and clipping)

[johandm_be]

Hi Larry,

Thanks for the suggestion. I actually already started taking the mounting apart so I can add more anti-vibration. When I am done and the vibrations are still too high, then I will post some pictures.

Thanks & kind regards,
Johan.

[chschmid]

Hi Johann

Thats the wrong way around. You need to keep the vibs of your system down. If you just cover the vibes with some dampeners, it could backfire when the vibes go into some haromics or go in resonance with your build. And thats usually a crash.

Cheers
Christof

[johandm_be]

Hi Christof,

That makes sense - we're better off getting no vibrations at all as opposed to try to damp them for the AQ. Now, we did already carefully balance the props (only static balancing though), and the frame is quite rigid.

I think today the connection between the AQ board and the frame may have been too direct. We do want a layer of damping material between the AQ board and the frame, right?

Thanks and kind regards,
Johan.

[chschmid]

Hi Johann

Not necessairely. Most users mount the board on short nylon standoffs. I personally tried many different mounts including very sofisticated ones with complete isolation from the frame when I had vibs with a magnitude of 1-1.2 in one axis. I even tried many different dampening materials. No good results with that either.
But what finaly did the trick was using dynamically balanced props. They cost a little more but it pays off due to less crashes.

Cheers
Christof

[johandm_be]

Hi Christof,

I see; I wasn't sure whether it is OK to mount the AQ board on nylon standoffs with no damping material. You just confirmed me that you can do that.

With "dynamically balanced props", do you mean special props that you buy this way or do you mean balancing the props while they are mounted on the motor?

If it is the first (something I need to buy), can you give me some information like makes/models and also where I can get these?

Thanks again and kind regards,
Johan.

[chschmid]

Hi Johan

The Tiger Props are very nice.

Sometimes hard to get but nicely dynamically balanced.

I had also good results with this one 10x45.


There are also MK props in few sizes, but they are to expensive (ca 40E a Piece).

Balancing your drives might be difficult. I just ordered a dynamicaly balancing tool. I will report my findings after testing it.

BTW what sizes props and what motors do you use?

Cheers
Christof

[johandm_be]

Hi Christof,

I *was* using these motors:
http://www.unmannedtechshop.co.uk/multi ... 880kv.html

But: today I decided that I will be replacing them with new ones. The motors that were on the frame have been used (and so is the frame; it used to have a different autopilot on it) and I want to make sure these motors aren't contributing to my problem.

I placed an order for 4 of these: (T-motor MT2216)
http://flyduino.net/Multikopter-Brushle ... er-T-Motor

The props I am using are CF 13x4 from RCtimer:
http://www.rctimer.com/product_775.html

Which dynamic balancer tool did you order?

Thanks & kind regards,
Johan.

[chschmid]

Hi Johan

Nice Motors. But your props are very big.
Whats the AUW of the quad?

Here you can do some Basic calcs:


Cheers
Christof

[johandm_be]

Hi Christof,

I know the props are big. That was chosen intentionally, to get better hover time.
Yes, I do use that calculator too

The AUW is 1740g; it can take an additional payload of 1100g in this setup.

I am curious to know what dynamic balancer tool you ordered. I was looking for that too today but I did not find any?

Thanks & kind regards,
Johan.

[chschmid]

Hi Johan

Sorry, I missed that.


Cheers
Christof