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View Full Version : Vibration or What???


daniedb
02-15-2006, 06:36 AM
Hi guys,

Need some Xpert advice.
I have a Video Cam on my heli's. Sometime, I have a wobbling video image. It's not vibration, but seems like some interferance or something.
My cam is mount with a Bigger skied on the CG (Thats right below the main shaft). Could that be the reason.
I figure out that, when I increase my head speed is work much better.
If you need an example VIDEO, I'm willing to post it.
Would it be better to move the Camera towards the nose of the heli.

I'm new to the Video stuff, the Photo's come out pretty nice...

Thanx guru's
Cheers
Danie

daniedb
02-15-2006, 12:27 PM
I've just took an example video (30minutes ago) 12:35 South African time, with the problem I have. Anyone that can give me some Idea on why this happens.

http://www.aerialcam.co.za/down/vid.wmv

Thanx
Danie

Rugar
02-15-2006, 01:10 PM
The link wont work for me.

loker
02-15-2006, 03:56 PM
I just started too. I have an airplane, and I took pictures that were blurry, without noticing vibration. then after thinking it was possibly vibration, I checked, and there was a reeeaaally small amount of vibration. I put on a brand new balanced prop and new collet, and voila, problem solved, even though the vibation was so small, it was the problem.

daniedb
02-16-2006, 06:43 AM
try this and select the file.
Donno why it dont want to work

http://www.aerialcam.co.za/down

daniedb
02-16-2006, 06:46 AM
>> I put on a brand new balanced prop and new collet, and voila, problem >> solved, even though the vibation was so small, it was the problem.

That I thought was the problem aswell on my Heli. After spending about $350 on new main and rotor carbon fibre balanced blades I still pickup vibration.

I still think I'm to tight and maybe need a dumpers or something on the stand

Ira
02-17-2006, 03:38 AM
Hi Daniedb, Had similar problems when I first got my heli going. On a heli there are many places for vibration to start ....and then there are harmonics. If it spins or rotates balance it very carfully......twice. Double check your blade tracking. Lower frequency vibrations are probably rotors,balancing or tracking. Higher frequency probably tail rotors, balancing tracking or some other small rotating part. You will not be able to eliminate all vibration at all speeds,(if you do tell me how you did it) so some kind of isolation mount for the camera is needed. My Raptor 50,(please no cracks about slime) is very smooth but only after a lot of effort. I'll try to post a pic of the mount. Notice every efort has been made to keep it compact and STIFF to avoid harmonics.Also all cross braces are of slightly length for the same reason. And all I use this for is still shots! Now you can see why I've seen the light and invested in an eletric powered Magpie AP wing bird.

vidmaker
02-17-2006, 04:27 AM
The distortion you're getting looks like the camera has a c-mos sensor, try a camera with a ccd sensor an see if the problem goes away. My first camera had a c-mos sensor, all of the pictures would have a wavey distortion if the pictures were taken with the power on.

vidmaker

bhchan
02-17-2006, 05:37 AM
I think vidmaker is correct, I had a c-mos sensor camera that did not like vibration at all. On a helicopter, there is no quiet moment, something is shaking at one time or the other, unless it is powered off.

Brian, an EAJ

Ira
02-17-2006, 07:16 PM
C-MOS type cameras are more sensitive to vibration. All cameras will provide better results,( not to mention last a lot longer)if vibration is reduced as much as possable and the camera is isolated from the remaining vibration ie...mount isolated from the bird and camera isolated from the mount.

daniedb
02-20-2006, 08:47 AM
Looks like I got rid of the problem. Seems like everything was to tight mounted on the heli. I've loosen up some mounts, add some rubber mounts, and add springs for little stability.

Thanx for all the great suggestions.

Have a look at my setup at http://www.aerialcam.co.za click on the equipment link

Cheers
Danie