Aeronavics / Droidworx AD8 HL & 360 gimbal

[Blacksails]

I've noticed that the joint that connects the av200 360 mount to my AD8 is quite wobbly/fragile. This is fine, as I'm careful with it....but I can't turn up my RSGS gimbal stabilisation gains due to this.

I can set my roll gains on the RSGS to 600 on the bench and have no oscillations even when flicking the tray. But in the air, the wind hits the gimbal which causes it to wobble very slightly. This in turn causes the RSGS to correct for the wobble.
Due to the springyness in the 360 pan joint, the wobbles amplify, causing the RSGS to correct even more. This goes on and on. All in all it ends up with the oscillation finally affecting the wkm and the whole copter shakes.

I know people will just say to turn the gimbal gains down, but I'd like to find a solution to allow me to run the higher gains. For flight, my gimbal gains have to be below 150.

Are there any tips for reducing the play/spring in the 360 pan mount so that I can run higher gimbal gains?

Other than this, I'm very happy with the frame/setup as a whole.

Cheers guys

Alex

 

[droidworx]

I've noticed that the joint that connects the av200 360 mount to my AD8 is quite wobbly/fragile. This is fine, as I'm careful with it....but I can't turn up my RSGS gimbal stabilisation gains due to this.

I can set my roll gains on the RSGS to 600 on the bench and have no oscillations even when flicking the tray. But in the air, the wind hits the gimbal which causes it to wobble very slightly. This in turn causes the RSGS to correct for the wobble.
Due to the springyness in the 360 pan joint, the wobbles amplify, causing the RSGS to correct even more. This goes on and on. All in all it ends up with the oscillation finally affecting the wkm and the whole copter shakes.

I know people will just say to turn the gimbal gains down, but I'd like to find a solution to allow me to run the higher gains. For flight, my gimbal gains have to be below 150.

Are there any tips for reducing the play/spring in the 360 pan mount so that I can run higher gimbal gains?

Other than this, I'm very happy with the frame/setup as a whole.

Cheers guys

Alex

Hi Alex! I'll see if I can get some info on this from PhotoHigher - have not heard of these issues before! Stay tuned... :tennis:

 

[Blacksails]

Hi Alex! I'll see if I can get some info on this from PhotoHigher - have not heard of these issues before! Stay tuned... :tennis:

Thanks Droidworx :tennis:

Love the AD8 so far, it's a beautiful beast and always attracts attention. She's going through her BNUC-S flight exam in the next few days too!

 

[Droider]

She's going through her BNUC-S flight exam in the next few days too!

Good luck with your flight test. If you want any info on it PM me with any concerns with it.

Dave

 

[droidworx]

Oh that's exciting! Much success with that, let us know how you go...!

I contacted Kim and he replied following:

"Sure,

Can you ask him if he has the thrust bearing installed on the pan axes just below the Main pan pulley? This is an improvement we did last year but I am not sure how old his gimbal is? The next thing to look at – is the movement coming from the pan axes ie between the DW adaptor plate/Main pulley and the top of the AV200 or is it coming from between the DW adaptor plate and the gear rail tubes? The grommet could be a little worn or they may have dried out and are hard. If this is the case then Alex should look at replacing the grommets or even just to see it it is the problem he can put a zip tie or Velcro strap around the gear rail tube to try and take out the slack. If he does not have the thrus bearing assembly then he should contact us and we can organise one for him they are not expensive.

I hope this helps."

I hope too this helps! Let us know and again - much success these coming days...

Cheers,
Linda

 

[Blacksails]

Had to move my test date to next week due to weather conditions. :upset:

My 360 kit is the newest version. I've only had it for around a month. It has the thrust bearing and all of the grommets are new.

The kit isn't defective. The play is due to the fact that the frame is attached to the 360 gimbal at only the one fixing point and the gimbal has a fair amount of mass when loaded up with a camera...so it can and does wobble independent of the main frame in wind. All 360 gimbals seem to be made the same way though, so it's unavoidable to a certain extent.

I'm going to do some experimentation and see if i can reduce some of the play to allow the skyline RSGS to run higher gains. Will let you all know how it goes. I think the first thing to do will be replace the gear rail brackets with something sturdier. The polycarbonate ones tend to flex a little, this was fine with the standard landing gear but I don't like it with the 360 kit.

Cheers for the help Linda, much appreciated!

Alex

 

[marpunta]

Hi
Any news on fixing the problem
I think i have it to...

 

[redridinghood]

Maybe some images can help. The one I have feels very solid. Are you using the stiffener plate?

View attachment 6712

 

[marpunta]

Thanks
From the pictures i see i have every part in place
But what is the stiffener plate? (sorry...i am Greek)

 

[redridinghood]

Its the double aluminum plate that strengthens the part that mounts on the frame.

An exeis to Skyjib frame tote i nea plaka ine mesa sto kit. Ine i teleutea eikona kato de3ia.

 

[marpunta]

OK Thanks

I got it (το ΄χω...)

 

[Blacksails]

I fitted the stiffener plate and it hasn't made a blind bit of difference.

I've been having a play with it and have found that by wedging some dense'ish foam between the base of the AD8 and the 360 battery tray (on the left and right hand sides) it damps out a lot of the movement. Not a great improvement....but better than it was.

I think you guys with skyjibs that don't need the landing gear attached to the gimbal won't suffer from this as much. There's less weight on the 360 joint and therefore less inertia. Also, the landing gear is large and flat...great for catching the wind

 

[Helirazor]

We had a simular problem, there was flex in the pan main gear and had weakened. We added a spacer between the gear and cradle and a couple of screws.
Hope this helps.

cheers