vibration -> lost control

The last Bastion to fine tune your FC matching your airframe & setup

vibration -> lost control

Postby codeforge » Mon Oct 15, 2012 6:46 pm

hi,
i have a question... is it possible that many vibration could make lost of autoquad control?

i have a small quad that fly very well with 10x45 carbon fiber propellers. after a crash i change the propellers with plastic and after that i cannot control my quad. if i pitch forward or roll nothing chang in hovering. I try to change propellers and install 8x45 carbon reinforced and then i get again my quad very stable and that react to my radio. Change back to plastic 10x45 and lost again the control. Is an issue or is normal? what kind of trick i can use to remove vibration from motors? (i already use the tape on one side of every motor and test witn vibration app for iphone).
Even the graupner 8x5 eprop are not good... when i use it my quad isn't stable and don't react to command. i can use only the 8x45 carbon reinforced prop from flyduino that work very very well, but if i want to use 10x45? what kind of prop i must buy?

my motors are t-motor MT2212-16

thanks
codeforge
 
Posts: 104
Joined: Tue Jul 31, 2012 11:09 pm

Re: vibration -> lost control

Postby Max » Tue Oct 16, 2012 5:41 am

I'm in a very similar boat. Changed motors on my Y6 and got all sorts of vibrations. And to answer your first question, yes, vibrations can have a huge effect.

Those Gemfan plastic/carbon props need to be balanced at the hub as well as the blades. Makes a huge difference. In some cases you can clearly see the hole is off-center, especially on the "R" types. Also you have to check the tracking on each one (make sure the blades are in the same plane) -- I've tossed 3 out of 6 reverse ones because the tracking was 5-6mm off right out of the package. Most have a ~1mm variance, a few are perfect. But even one that looks good on the balancer might track wrong when spinning under load, so you have to check that as well. And it gets worse the bigger the prop -- my 12" Gemfans aren't usable at all, but the 11s are better.

After hours of getting the props picked out, balanced perfectly, and tested on the Y6 both individually and all together, when flying there is still a nasty vibration that sets up in very specific conditions, just on one arm. So I'm working on figuring that one out now... :roll:

I'm surprised the Graupners aren't better... I thought they would be.

I just placed an order with HiModel for some wooden JXF props (no 10s though :( ) and a couple sets of their carbon ones in 10 and 11 sizes. I guess for 10s I'll try APC next.
Max
 
Posts: 2814
Joined: Mon Aug 13, 2012 9:45 pm
Location: Near Ithaca, NY, USA

Re: vibration -> lost control

Postby codeforge » Tue Oct 16, 2012 9:11 am

hi,
yes i don't know why graupner don't flies, i have the same frame an motor with an arducopter and using same size graupner it flies perfect... But i will buy carbon prop again because i need 10x45 and i want to be sure that there aren't vibrations. My arm are thin so i cannot use wood prop. Good luck with your y6.

nice day
codeforge
 
Posts: 104
Joined: Tue Jul 31, 2012 11:09 pm


Return to PID Tuning

Who is online

Users browsing this forum: No registered users and 16 guests

cron