RC India

RC Models => Multirotors => Topic started by: Sruthik on May 18, 2014, 02:20:22 PM



Title: Help: Stabilizing a quad for taking video
Post by: Sruthik on May 18, 2014, 02:20:22 PM
Hey guys,

       I'm building my first quad which will have a gopro mounted on it. What are the precautions to be taken to reduce the vibrations caused by the quad? I'm looking at a Turnigy HAL Quadcopter Frame (585mm) which has an add on 3 axis camera mount. Will that be enough in stabilising the camera?

Oh and I've just completed my 12th, so a total noob here.
Thanks!! :)


Title: Re: Help: Stabilizing a quad for taking video
Post by: roshan.dixit on May 18, 2014, 11:34:03 PM
DONT USE A STIFF FRAME!!  Use Dampners,  properly balance props!!  And motors try isolate vibration on the frame by placing the camera away from the frame


Title: Re: Help: Stabilizing a quad for taking video
Post by: Sruthik on May 19, 2014, 07:54:27 AM
Thanks a lot Roshan  :) Is making my own rubber dampener viable or shall I buy four of the readymade ones? (Am on a budget..so) And when you say don't use a stiff frame, do you mean the stiffness of the material being used to make the frame of the quad?

Thanks again!!


Title: Re: Help: Stabilizing a quad for taking video
Post by: roshan.dixit on May 19, 2014, 12:52:55 PM
You can make your own wait will send you photos and link are u on whats - app?? Stiffness of the frame is directly proportional to vibration!! You cant get a CF or GF frame without being stiff so try to isolate the camera


Title: Re: Help: Stabilizing a quad for taking video
Post by: Sruthik on May 19, 2014, 07:19:11 PM
No, I do not have an acoount on WhatsApp but am on Facebook. And, yeah I got the stiffness part of it. But which material is less stiff? Carbon Fibre or Al?
Thanks again!!


Title: Re: Help: Stabilizing a quad for taking video
Post by: allthatido on May 19, 2014, 07:48:44 PM
Wood>>>Aluminium>>>Carbon Fiber

In decreasing order of the ability to absorb vibrations


Title: Re: Help: Stabilizing a quad for taking video
Post by: Sruthik on May 19, 2014, 10:33:50 PM
Thanks,
          But is constructing the frame with wood viable? Or shall I go for Aluminium? Wood is cheaper so it would help me.


Title: Re: Help: Stabilizing a quad for taking video
Post by: SideWinder on May 19, 2014, 11:08:41 PM
As Ankur said wood is the best material to absorb vibration but its is weak, but yet if you can limit the size of the quad to 300/350mm then it should be fine depending on the type of wood you plan to use, and ofcourse its cheap and easily replaceable in the event of damage depending on the design of your frame.

Anyways vibration is not generated due to frame but its due to motors and props. Frame would be ideally passing on that vibration to the camera or FC or anything mounted on the frame for that matter. So try to isolate the camera from the frame by using anything you have at hand which you think can absorb vibration.

For ex. I have seen people using foam ear plugs cut in half equally and arranged as four legs and then mounting go-pro over it and being held on to the frame with rubber bands. There video were a lot better.

So go ahead and use wooden booms, but was wondering if you can fit square shaped booms on that frame? Or are you going to completely scratch build your frame?
Similarly you didnt mention which camera you are going to use, because solutions would be different depending upon your camera.

PS: Carbon fiber(CF) is not so bad for AP, you just need to mount your camera properly. Most of the professional AP multirotors are made of CF


Title: Re: Help: Stabilizing a quad for taking video
Post by: Anirudh Ravi on May 19, 2014, 11:44:22 PM
Hey there Sruthik... the best way is to isolate youre gimbal from rest of youre frame...this is one of the best ways to do it if not the best... im building one for myself right now...https://www.youtube.com/watch?v=nEaTO2twSxc (https://www.youtube.com/watch?v=nEaTO2twSxc)
 but if i were you i would first worry about getting the quad to fly right... i also built my quad when i finished 12th...
this a video of my quad... completely made off wood but trust me i ended up using aluminium to stiffen it anyway...
https://www.youtube.com/watch?v=uFZrpFYZ4gQ (https://www.youtube.com/watch?v=uFZrpFYZ4gQ)


Title: Re: Help: Stabilizing a quad for taking video
Post by: Sruthik on May 20, 2014, 09:13:15 AM
Sidewinder, initially I'll be using a GoPro Hero 3+. I actually wanted to mount a dslr but poked around and found out that Hexacopters are better for them.So, gopro it is. Does m-seal absorb vibrations? I was thinking of using mseal b/w the gimbal and the frame. As this is my first quad, I thought of getting frames straight from HK, but doing my own seems more fun. So, I'll be constructing my own frame

Thanks

Anirudh, I saw your videos. The vibration isolator is a good start and I'll DIY it. Your wooden quad looks great too. But, if we use a heavier camera on the isolator, won't it get elongated?


Title: Re: Help: Stabilizing a quad for taking video
Post by: allthatido on May 20, 2014, 11:57:33 AM
Thanks,
          But is constructing the frame with wood viable? Or shall I go for Aluminium? Wood is cheaper so it would help me.

Here is a tricoptor made from wood (Lipin patti) by Sunlikestar (Amit Singh) flown at Pancard field, Pune.

http://www.youtube.com/watch?v=SoPqfD2YSRs#ws (http://www.youtube.com/watch?v=SoPqfD2YSRs#ws)

I am sure a quadcopter is also feasible with the same. But be cautious, if you are aiming for long flight times, go with carbon fiber and try to reduce vibrations at the source. Wood and aluminium multirotors will not give you exceptional flight times.

The tri above flies 7-8 minutes with a 2200 lipo.

EDIT : I just read this will be your first quad. I would suggest you make a wood/alu quad first and learn to fly. When you are confident of your skills order a CF frame and add camera/gimbal or anything else you want to.

And btw we had 3 such tricoptors on the field and collectively have crashed more than a dozen times. Not even once the frame broke as it is a folding design with everything mounted with zipties. The only victim each time a crash occured was the prop.


Title: Re: Help: Stabilizing a quad for taking video
Post by: roshan.dixit on May 20, 2014, 02:43:51 PM
ankurkaul17 I Agree with you would also like to advise to use micro RTF quad as the hubsan etc!! For practice and orientation (-:


Title: Re: Help: Stabilizing a quad for taking video
Post by: Anirudh Ravi on May 20, 2014, 05:08:07 PM
Yss i completely agree with Roshan... If you haven't flown before you have to get a feel for it and orientation is a key... If you loose orientation and if you're flying in a confined space you're a goner for sure... I would suggest the ladybird cause its what i learnt on... I also got some aerial footage with it...http://m.youtube.com/watch?v=muQse28mqok (http://m.youtube.com/watch?v=muQse28mqok)
And to you're question... Yes if there is too much weight it will sag... The way you do it is that you start with a thick and stiff wire and then remove strands of the wire till you get to where you like it...


Title: Re: Help: Stabilizing a quad for taking video
Post by: SideWinder on May 23, 2014, 10:46:31 AM
One of the DIY solution for vibration dampening

http://www.youtube.com/watch?v=NdGQpV2jevs#ws (http://www.youtube.com/watch?v=NdGQpV2jevs#ws)