VAB roof capable crane

[klond]

 Capable doesn't mean good or easy or not-explodey.  Had success on this 4th recording attempt.  'Got lucky - the arm swung back down when I braked. I was determined to get something up there.

KerbalX

 

Edited September 26, 2016 by klond

[Matuchkin]

I don't care how explodey this is, it's perfect. Never quite seen a crane so huge.

But can we have a display of how much can it actually lift? Like, push it to its limit.

Edited September 26, 2016 by Matuchkin

[klond]

 I didn't want to make it huge, but the large, heavy parts are far more rigid and keeps the part count lower.  Turns out the VAB is really tall.  The crane doesn't really fit in the hanger where it was built.  Had to keep sliding 1/2 of it out the door to work on it.

2 hours ago, Matuchkin said:

But can we have a display of how much can it actually lift? Like, push it to its limit.

 Feel free to download and go to town on it.  If you keep adding fuel tanks to the rear, you should be able to lift more and more until parts start exploding under strain - but we're already nearly at the limit of the hanger for building space..  Post a pic if you lift some neat stuff.

Edited September 26, 2016 by klond

[Majorjim!]

Man that's big! I kinda looks like a trebuche. You should make one!

[Avonix]

Kerbal Crane Program.

 

I can only imagine the stress your PC must be under from that. What sort of FPS do you get with that thing?

[RandyRawgust]

How does the pivot point work? I need a crane to lift my landed rockets off my ASDS, so I'll need to cut part count down welding it together.

[klond]

Thanks for the interest.  Sorry for the delay in response.  Work = bad.

On 9/29/2016 at 7:18 AM, Avonix said:

I can only imagine the stress your PC must be under from that. What sort of FPS do you get with that thing?

I5 with a gtx480.  15-22fps.  Not horrible.

On 9/30/2016 at 4:14 AM, RandyRawgust said:

How does the pivot point work?

Until staging the whole machine is one unit.  After staging it splits into these 3 parts.  The base, the boom, and the swinging grabber.  The base was built first and the boom is attached by a seperator/decoupler and some struts.  When it's staged it comes apart and floats on landing gear.

There's 2 more of those landing gears clipped into the base underneath the giant hub on each side.  There's a little metal end piece to keep the hub from sliding off it's mount.  An updated version of the crane has a cap on top of the bearing so the whole boom doesn't pop out, and an extra little end cap holder.  KerbalX link is in original post.  Download and have at it.

Edited October 2, 2016 by klond

[RandyRawgust]

Marvelous engineering!

[Rath]

Wait... So its balanced well enough that only those three wheels can move it?  Wow.

[klond]

12 hours ago, Rath said:

only those three wheels can move it?

 The landing gear is just acting like a ball bearing, it's not providing any oomph.  You move the boom by teeter-totter action through pumping fuel fore and aft.  A heavier load is going to require more fuel to be pumped back.  You do the balancing.

[Rath]

I was thinking of the reaction wheels.

[klond]

14 hours ago, Rath said:

I was thinking of the reaction wheels.

 Oh.  I threw them on to help reduce vibration and bounce.  'Can probably delete them and be ok.