Mod stock parts question, reducing wobble between coupled parts?

[Markus Reese]

Hi, I have been working on a new project to move a rather big ship to another planet. Because of roleplay, and fun, I have been making a massive drive system in space with return capsule, lander rovers (done aerodynamically). Anyways, across the couplings, there is wobble. Is there something that can be modified in the stock parts settings that can reduce the amount of wobble? I cannot see a setting that stiffens up the stock part.

Edited June 6, 2013 by Markus Reese

[Nachtwind]

Well, there are mods you can use. I used Quantum Struts and Docking Struts back when i created my interplanetary space stations.. might be something for you.

[Scrogdog]

Try attaching radial hard points using symmetry then "stitch" the seams using struts.

[Markus Reese]

Docking struts would be cool. Will get them for sure next time, unfortunately spent past week getting it all together so would rather not build it again XD

As long as I dont turn on ASAS, it is good, well, just need to top up fuel and see how it handles with a bit of thrust!

[Sᴄɪɴᴛɪʟʟᴀᴛᴏʀ]

Are you using the docking port Sr.?

[Markus Reese]

Hmm... let me get some screenshots here, that will help. Be a couple minutes.

[Arran]

I allways put some struts along the side of decouplers when i notice it too unstable, and gets wobbly, same for when i use docking nodes.

For in orbit, i use Quantum struts which i place in a action group too turn on/off when needed.

Here is some example, on how i reworked a rather wobbly design, into a rigid structure

Its not the best example, didnt had any better ones ready yet, but i think you get the idear

https://www.dropbox.com/s/v3zpc4bsxgy3mlp/Squid_launchpad.png?v=0mcns

The lander/Kethane drill is connected with KAS too the rover, and supported by quantum struts, what again is connected too, the lifter itself, supported bu a quantum strut gun onto a small red decoupler, onto a docking node, The Lifter itself is build within a framework(allmost a scaffolding of struts) of struts too keep this tall rocket ridgit.

Without the framework and Quantum struts, it would been utterly uncontrollable and wobble all over the place till it tore itself apart

But in the framework of struts it even was alot more stable as espected, and could bring it perfectly too the Mun for its mining operation.

Edited June 6, 2013 by Arran

[Markus Reese]

Here are some screenies to show the assembly. The main problem is less it gets wobbly, but more it starts twisting. By all rights, I could use an exoskeleton with couplers to make it all rigid, but will rather prefer to put off doing that at this time.

Anyways, you can kinda see the structure. I underestimated it a bit. Since this was a project started in 19. I am not worried about modifying stock parts to get my video project done. New instance will be started once rescue is completed. Third booster is currently not docked to show structure.

Edited June 6, 2013 by Markus Reese

[Tripod27]

what are docking struts? can't find them in the spaceport

[Arran]

Do you have several RCS units on the structure, and attacked vehicles, asas/sas units.

I am far a expert, just a trail and error kind of designer but when i attach vessels too a main carrier, without a rigid structure, and with the vessels not utterly passive, i get weird spinning and wobble like effects.

So i prefer Remote Tech over MJ on big ships, and use only RCS and RT, mechjeb i only use for it info Displays nowerdays so its passive. and tie everything together with those quantum struts.

Then i turn all RCS off, and only use those one the main ship, where i have RCS trusters placed on its grav center, with all things attached too it.

And use directioma; trusters on it ends in 4pars too supper the main RSC units it turning.

ANd i fiddle with the gibals of the engines, keeping the centre one as steering engine, and the ones outside with gimbal turned off..

Most weirdest designs i made, where at least "usable" this way (not that they worked as intended )

i assume you have footage of the ship, and adding a exoskeleton around it, would alter its appearance too much, and redoing the scenes would be alot of work..

Maybe use a structure of Quantum struts, and modify the Textures so they dont show up ingame, just function i'm not a modding expert in KSP, but i assume the mod can be altered in such manner.

In regard of a "movie" making i think this would do the trick, so you dont need to do all the footage all over again.

Edited June 6, 2013 by Arran

[Markus Reese]

Oh scrog, missed your comment earlier. What do you mean by stitch struts? If you dock, will struts connect out or something?

[Scrogdog]

Yeah, sorry about that. I kind of mis-read your OP but your pic made your issue more clear. I was speaking about strengthening seams to reduce overall wobble in your ascent profile, not docking.

Though, upon further thought, it depends on how the wobble is manifesting itself. Is it occurring right at the link or behind the part? Not sure I get what you mean when you say it occurs across the connection, but that sounds like right at the link. Don't know what to do about the former, but some struts might help with the latter case. I'd have to test.

What we really need is Kerbals capable of adding struts during EVA.

Anyway, iirc, the last time someone brought this up, he or she ended up using the editor so he or she could remove the docking ports and make regular strutted connections. The editor allowed putting the whole assembly back up in orbit.

[Markus Reese]

Managed to carefully thrust my way out of orbit. So far with stock parts I think an exoskeleton design will be the only real way to stiffen up large ships. When done with this one, Will have to set one up for another trip later.

Cause was springyness in the Docking ports itself for alot of it. Some was due to length. Once I get to eve and can ditch the lander portion, it should work alot better.

Edited June 6, 2013 by Markus Reese

[Scrogdog]

So far with stock parts I think an exoskeleton design will be the only real way to stiffen up large ships.

Yeah, that's probably correct. Should be an interesting concept to play with. I'm pretty far away from that concern at the moment.

[randyre]

What I'd like to see is at least for identical parts that are attached to each other, make them automatically rigid as if one part, there should be no reason to "brace" identical parts.