Why does this Station destroy itself through phantomwobbling?

[Farex]

Greetings,

wanted to set this Station around Minmus. Everything worked great until I tried to dock another craft. The station just started wobbling uncontrollably and destroyed itself.

There is no Partclipping or strange things in it. It just starts wobbling once you leave it in space.

Why is that?

http://www./download/xo950i80c9211al/Erzstation+mk1.craft

Thanks for possible help.

[Claw]

Thanks for including a craft file. A screenshot would also be handy (I'll have to download the file later).

However, this is often due to mass imbalance along with not enough (or misplaced) struts. The physics engine then creates a sort of resonating loop where the wobbling gets worse and worse.

Strategic strutting is often the best bet, but sometimes turning off SAS also helps. I'll have to fiddle with the craft later, if someone doesn't beat me to it.

Cheers,

-Claw

[Farex]

Ok, here is a picture.

Once you separeted the last booster and switch to another craft, try to dock it and as soon as you get in it's physicsrange the lower half starts to wobble, between the two oretank-segments.

Edited October 2, 2015 by Farex

[Harry Rhodan]

That lower part is basically a huge spring with weights attached to more springs. The only thing keeping it stable are the struts that connect it to its transfer stage. Once you drop that any slight wobble introduced will probably make that reaction wheel go mad because it has to constantly counterreact in all directions at once. The solution would be the traditional MOAR STRUTS and maybe using a big reaction wheel in the vicinity of the CoM instead of small wheels on the strut segments.

[Kaezan]

Disable all reaction wheels and let it wobble for a while (~10 sec is enough) then turn on just one reaction wheel.

I had the same problem and it was caused by multiple reaction wheels trying to compensate each other

[Farex]

@Harry

The solution MOAR STRUTS helped indeed. Didn't think that this lower section would be such a spring-system, fairly impressive to achieve something like this out of nowhere. Danny would break the game with this, I swear.

The small reaction wheels + batterie are a designchoice, it makes the dockingport look better :-)

@Kaezan

Disabling SAS just sped the wobble up. SAS did hold it together (somehow).

----

I will have to keep this in mind, would be a shame to build something with this spring-system and send it to eeloo, jool or something only to see it making unkerbalish dancemoves.

Springsystem. Hm.

[revan1611]

I know this thread is old, but i want to add my 2 cents on this for other players who might encounter this issue.

When you build station module, enable autostruts on all parts to "heavier part" for in line modules, and for radial modules "root part" autostruts. This method helped me.

[Superfluous J]

43 minutes ago, revan1611 said:

I know this thread is old, but i want to add my 2 cents on this for other players who might encounter this issue.

When you build station module, enable autostruts on all parts to "heavier part" for in line modules, and for radial modules "root part" autostruts. This method helped me.

I've found that too many autostruts (or regular struts) is more likely to cause problems than solve them. I find that just a few sparse autostruts spread around the craft in key places is the best course.

[revan1611]

On 7/19/2018 at 5:03 AM, 5thHorseman said:

I've found that too many autostruts (or regular struts) is more likely to cause problems than solve them. I find that just a few sparse autostruts spread around the craft in key places is the best course.

You're right. Found out when i was trying to dock another module, and that station still wobbled, so i disabled unneeded struts and it's all fine now.

Edited July 20, 2018 by revan1611
grammar correction