Hello, good afternoon all.

Anyone knows if it is normal inspire 2 vibrate without the camera, and  if with the camera mounted, still have a little vibration.

pd: sorry for my english, i hope understand my concern.

Regards.

links videos:

Inspire 2, without camera


Inspire 2 + Zenmuse x5s

To a degree it is normal to all UAV's due to minor off-balancing of propellers and/or motors. It may be noticeable at particular motor speed (i.e. when hovering), and disappear after acceleration. In perfect scenario the motor and propeller assembly should be dynamically balanced at full speed range. which is the task extremely difficult to perform.  Four propellers even slightly unbalanced will create standing waves of low frequency vibrations at particular speeds, which is the case.  If the vibrations doesn't result in shaky (yello-ed) video when filming at average aircraft moves, ignore it.

Here's a trick to determine if these vibrations are worrying worthy: attach an GoPro camera to a belly of your drone (with sticky holder) and record the views of motor booms during flight. Unlikely very turbulent vibrations may challenge the integrity of the frame...

Might want to try and balance the props (Especially right rear.) and also see if they are snug and don't wobble which seems typical of the DJI props.  You could use CA Medium glue and run a bead under the props (Allow overnight to dry.) to tighten them up if needed.

DuBro makes a prop balancer and you need to find or make a shaft to fit into the blades.  Two of mine out of the eight supplied were out of balance and five needed the CA glue treatment to tighten them up on the mount.

DuBro Balancer
Balancer shaft

fansa84fe8a4 Posted at 2017-10-24 15:50
Might want to try and balance the props (Especially right rear.) and also see if they are snug and don't wobble which seems typical of the DJI props.  You could use CA Medium glue and run a bead under the props (Allow overnight to dry.) to tighten them up if needed.

DuBro makes a prop balancer and you need to find or make a shaft to fit into the blades.  Two of mine out of the eight supplied were out of balance and five needed the CA glue treatment to tighten them up on the mount.

Prop balancing is a matter of past, perhaps still necessary for DIY aircrafts in hobbyists community, IMHO. DJI props are just fine (persistent I2 mount rattle aside) and badly performed balancing may simply worsen the situation. Just my 2 cents ...

Dobmatt Posted at 2017-10-24 17:07
Prop balancing is a matter of past, perhaps still necessary for DIY aircrafts in hobbyists community, IMHO. DJI props are just fine (persistent I2 mount rattle aside) and badly performed balancing may simply worsen the situation. Just my 2 cents ...

And you'd be proven wrong by a couple of mine.

They haven't gotten the mold right for the ill-fitting and loose props for almost a year now so what makes you think they are properly balanced?  This isn't military spec'd gear, nor given quality time to balance and assure proper fitting for each prop they make.

I'm no expert, but that seems like a lot of vibration.  Have you tried the spare props to see if the problem goes away?

Firstly, I agree with Mr Mister that trying the other props is worth a go.

I think that the fact that the vibration is reduced with the camera fitted, indicates it is acting as a damper for a resonant frequency.

I note that the I2 does not  appear to be flying at any great altitude, and that the aircraft may be in ground effect.

I come from a helicopter background, and resonance in ground effect is not unknown, in full size aircraft.

If the prop change doesn`t do it, fly at a slightly higher altitude and see if the problem goes away.

fansa84fe8a4 Posted at 2017-10-24 17:22
And you'd be proven wrong by a couple of mine.

They haven't gotten the mold right for the ill-fitting and loose props for almost a year now so what makes you think they are properly balanced?  This isn't military spec'd gear, nor given quality time to balance and assure proper fitting for each prop they make.

All I'm saying is that DJI prop balancing is extremely difficult to perform properly. It requires a lot of knowledge and experience. It's a rocket science, really. I quit worrying about it after several unsuccessful attempts.

Sanding off a few particles too much or in wrong spot will make a difference on Du-Bro stand. Now, take into account unreliability of balancing shafts. With many poorly designed incarnations available on eBay, the shaft end will attempt to sit tight and solid in prop mount cavity. This cavity is manufactured with loosely specified tolerances, which - in some causes - results with props rattle. You may be able to eliminate this rattle by home-cooked shimming of some sort, but only vertically. Off center mounting variables are impossible to manage, therefore rendering the balancing process unreliable. Another words, what may seem to be right on Du-Bro stand, may be just wrong on Inspire prop mount.

I haven't seen any properly design shaft end (by far) to sit properly in rectangular opening of Inspire quick mount props. I've heard about handmade adapters, carved off wood block ... Please correct me if I'm wrong.

These issues are irrelevant in case of conventional props balancing, which are made with a single center hole to fit tightly on motor shaft and secured by single nut. Since DJI introduced "quick" mount concept, the entire idea of prop balancing went down the drain. Too many variables, impossible to manage. The props itself are just fine and must be consistent. Quick mount design or manufacturing faults, however, is another story.

Good luck with your balancing, anyway ...  

If your props have a wobble then I'm 99% sure that this can result in the entire AC vibrating.

I witnessed this happen and immediately grounded mine until I fixed the issue with a layer of glue on each prop.

So far, no further issues.

My advice is not fly until you have researched and found a method to stop the vibrations. They could be much worse when flying at speed and you'd never know until it's too late.

There are also other models of props available.

Thanks all for yours advice and time to answer. I hope can fix this.

Regards

Tangaroa Posted at 2017-10-25 17:01
Thanks all for yours advice and time to answer. I hope can fix this.

Regards

The hub is far from 100% center. What can really help when there is excessive vibrations. Just mount the prop 180 degrees and test again.
Also using the Du-bro to balance props. Very easy with the hub attached.

PH2DW Posted at 2017-10-26 05:10
The hub is far from 100% center. What can really help when there is excessive vibrations. Just mount the prop 180 degrees and test again.
Also using the Du-bro to balance props. Very easy with the hub attached.

Yes, I did the 180 degree rotation thing when I encountered my two heavy-sided props where the other six were fine.  It was like a penny was on the end of the prop on the two heavies.   Bad injection mold pressure maybe or bad plastic mix.  Anyway, they are better now and behave like the other six, along with the CA Medium glue bead on the undersides to snug them up in the mount too.

Even in GPS mode, it is hard for aircraft to keep absolute stable, please check the GPS Hovering Accuracy in specs.
Please note vision system performance may be affected when flying above grass, since the grass may absorb ultrasonic.