Large ships wobble themselves to smithereens spontaneously (modded AND vanilla)

[daskraut]

Did this happen to anybody else / can you reproduce this bug?

To see the bug in action check

Environment:

KSP 0.25 32bit, downloaded via Steam

Modded AND unmodded

Win 7, all current updates

Recipe:

+ 4 3.75m tanks or half-tanks connected to a centerpiece in an X-pattern like seen in the above video.

+ It doesn't matter if they are connected to the centerpiece directly with a truss piece as spacer or perpendicular to an X-shaped I-beam structure, parallel or perpendicular to the main structure, connected directly or docked (tried all combinations).

+ Bug appears not to occur with empty tanks, total mass might matter here.

+ SAS and RCS don't make a difference.

+ Happens randomly and on load from tracking station.

+ Catastrophic failure can be prevented by going back to the space center without saving, then reloading the flight from the tracking station (involving a certain loss of progress).

I will now delete the game completely and try to replicate the bug with a completely fresh installation. Expect follow-up post this evening.

[daskraut]

FOLLOW-UP: The bug is reproducable in a completely fresh vanilla installation.

[Alshain]

I think this is a known issue with the cubic octagonal strut (truss) pieces. When attached at the right angles they tend to do that.

Scott Manley had a very humorous self destructing rover he constructed using KAS. Same issue.

Edited October 29, 2014 by Alshain

[michaelhester07]

I think i've seen that happen before with those tanks directly attached radially to a central tank. It was a 6x duplication. When i switched to the ship it would rip itself apart randomly. No throttle, no SAS. Mostly stock parts.

[toril]

say hello to the kraken. Seriously. This usually happens when you attach a large mass to a mass less part ie the cubic strut it causes a math error. You can fix it by adding mass to the truss(via mm config) and not putting any reaction wheels on the stacks your connecting like that. I can't tell from the video but it does look like you have reaction wheels on the tanks. keep those in the center stack if at all possible otherwise attach it with a more substantial part.

[Capt. Hunt]

also, moar struts

[daskraut]

funny thing is - i always used this pattern for my orbital fuel depots, only it used to be 8 2.5m tanks instead of 4 3.75m tanks and it worked perfectly fine with no issues whatsoever.

it causes a math error.

the bug is already known? - good, so it might get fixed

it does look like you have reaction wheels on the tanks.

i had 2 on the center stack between the tanks, close to the center of mass. the cupola's torque was turned off.

also, moar struts

which is sad cos i hate struts on orbital installations, especially if they're relatively small like this here gas station...