[SOLVED] Limits for Vibrations

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scvflyer
Posts: 98
Joined: Wed 22. Jul 2015 16:02:51

Hi Service team ,
I did my vbrations analyze and got following results - would you like to check it out and give me a feedback.
Test has be done without tail blades and without holder for tail blades - just tail gear and tail shaft (all brand new).
Some words about file names - first letter defines axis , following number RPM main blades , rest some words about test scenario .
By the way what would happen if vibrations are to hight during flight - will spirit system stop working ? Would i see shut down process at log file ? And final - are there ideas to bring log data to telemetrie bus - like HOTT ?
Thanks in advance br Siggi
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Gtamas
Posts: 109
Joined: Tue 17. Mar 2015 22:07:02

How the hell can a heli produce 90+ vibration without blades, , and even without blade holder?

What kind of machine is this? What is the setup?
scvflyer
Posts: 98
Joined: Wed 22. Jul 2015 16:02:51

Hi - it's TREX 600.
and displayed information, which isn't visible at the image, says raised vibrations for z axis
ZeXx86
Site Admin
Posts: 12836
Joined: Mon 29. Apr 2013 16:06:44
Contact:

Hi,

the vibrations are comming from the tail mechanics.

It looks like bent tail shaft of torque tube. It does not look like bearing issue as the spikes are very narrow, at specific frequency.
So first I recommend to examine tail shaft and possibly to replace it. Then I guess it will be much better.

Vibration data are already transmitted to Jeti transmitter via telemetry (at least value). But the upcoming update will add some feature that will solve it for all.
Spirit System developer
Adrian
Posts: 204
Joined: Thu 08. Oct 2015 14:43:12
Location: Switzerland

Tomas, please use rpm instead of Hz on upcomming release if possiple. I'm realy bad by muliply by 60 in my head. ;-)
Oxy4max SpiritPro + HW // SOXOS 550, SpiritPro, HW120A V4, 920KV // SOXOS 600, SpiritPro, HW160A, Pyro650 // SOXOS Strike7, SpiritPro, HW160A, Pyro750 // Skywing Spirit Aero // FrSky Horus X10S + Taranis X7 /
scvflyer
Posts: 98
Joined: Wed 22. Jul 2015 16:02:51

Hi tail shaft and bearings are already replaced. I will try to add an extra bearing at drive shaft (from front gear to back gear).
Hope it will help.
Some additional information
- normnal test - helicopter is placed at two woolen blanket
- if I lift up helicopter by hand the needle will be reduced round about 50%

thanks and br Siggi
Adrian
Posts: 204
Joined: Thu 08. Oct 2015 14:43:12
Location: Switzerland

Siggi, try to unmount everything rotating and than add in sequance doing vib analysis. Tube bearings need to be placed at exact defined spot, not at any Harmonics like 1/2 1/3, 1/4, as wave would build up. Also check different head speeds +/- 100 rpm as you might hit system resonance frequencey. Gruss Adrian
Oxy4max SpiritPro + HW // SOXOS 550, SpiritPro, HW120A V4, 920KV // SOXOS 600, SpiritPro, HW160A, Pyro650 // SOXOS Strike7, SpiritPro, HW160A, Pyro750 // Skywing Spirit Aero // FrSky Horus X10S + Taranis X7 /
scvflyer
Posts: 98
Joined: Wed 22. Jul 2015 16:02:51

Hi , to give you a feedback.
it's fixed by using a second ball-bearing at torqoue tube - like desoigned at 700er TREX
thanks and br Siggi :D
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