leaving external seat mounted into fairing/ cargo bay = sucide ?

[crackerbal]

hi,

watching for a lightweight vessels, i reaslise the best option to carry your crew over the space was to put a kerbal on EAS-1 External Command Seat

first what i tried was to put it into the fairing (i didin't try with a cargo bay but i assume it's working the same way), but when i land my vessel, leaving the seat results on an extreme acceleration for a kerbal transforming him into spaghettis

i supose when the kerbal leaves the seat he's shooting into fairing... and start to bounce between the fairing parties witch results on this kind of strange acceleration for him, anythink to fix that ? am i doing something wrong ?

[bewing]

Fairings are special. Especially fairings on the top of a rocket -- so that probably can't work.

If you use a cargo bay/service bay, it will work better ... provided that you mount the seat to the top or bottom, and not to the outside walls. The outside walls conduct heat, and so does the seat. And your Kerbonaut can only take 800C before he dies.

 

[Plusck]

6 hours ago, crackerbal said:

....leaving the seat results on an extreme acceleration for a kerbal ...

This happens all the time and I haven't worked out - or read anybody explaining - why this happens.

The Kerbal appears to somehow store up movement of the craft while sitting in the seat, and it inherits that velocity when he leaves the seat.

I can only suggest quicksaving before you ever take a Kerbal out of its seat. Reloading physics might help.

Alternative explanation: the Kerbal is considered to be clipping into the craft, even if the seat is completely clear of all obstacles. Therefore you get massive acceleration from that phantom clipping. Again, it doesn't happen all the time for any given seat, so reloading physics might solve it.

[crackerbal]

1 hour ago, Plusck said:

 Reloading physics might help.

maybe a stupid question but.... how am i do that ?

ps: i landed a vessel on kerbin at 60m/s everythink explosed but the kerbal somehow survived the crash he stand alone on the grass once the explosions end... love this seat into the fairing

Edited November 1, 2016 by crackerbal

[Plusck]

1 hour ago, crackerbal said:

maybe a stupid question but.... how am i do that ?

Oh, sorry. Basically go away from the craft and come back. Switching to a craft more than 2.3km away (or more, in the atmosphere, I never remember how far exactly), going back to KSC, or loading a savegame should work just as well.

The game keeps track of everything "on rails". When you go to control a craft, or when another craft comes within physics range, it loads the craft into the physics engine. Large craft, klawed asteroids and suchlike can often experience Kraken-like problems at that time. So the "physics loading" thing is just shorthand for that moment. However, I don't know enough about the nuts and bolts of it to say whether timewarp has quite the same effect.

[Shadowmage]

3 hours ago, Plusck said:

This happens all the time and I haven't worked out - or read anybody explaining - why this happens.

The Kerbal appears to somehow store up movement of the craft while sitting in the seat, and it inherits that velocity when he leaves the seat.

I can only suggest quicksaving before you ever take a Kerbal out of its seat. Reloading physics might help.

Alternative explanation: the Kerbal is considered to be clipping into the craft, even if the seat is completely clear of all obstacles. Therefore you get massive acceleration from that phantom clipping. Again, it doesn't happen all the time for any given seat, so reloading physics might solve it.

I think the plausible explanation for the kerbal velocity is that fairings, when closed, do not use concave colliders.  Their colliders cover the entire mesh as one solid object (or two objects, for a standard two-panel fairing).

The result is that the interior space, which -looks- empty, is actually filled with the colliders from the two fairing halves.  This doesn't effect parts on the craft as there is no inter-craft collisions, but as soon as the kerbal leaves the seat the physics engines sees him as occupying the same space as a collider and does what a phsyics engine does -- push the two colliding bodies out of collision; as the kerbal likely has the far lower mass, he gets a much larger portion of the velocity, and gets ejected/spaghettified.

I had thought that this was solved a bit in recent versions with fairings having multiple convex colliders generated to approximate their concave shape, but am still seeing a few oddities related to it.

 

Cargo bays might actually work better as they, for the most part, use a series of colliders to simulate the concave shape.  Though I had heard problems of thermals with kerbals-in-chairs-in-cargo-bays during the 1.2 pre-release, I think it may have been fixed.

[bewing]

There are two kinds of fairings. Interstage fairings do not have pointy tops and are hollow inside. That was part of my point in my first post. You can probably seat a kerbal inside an interstage fairing. But as you said, shadowmage -- fairings with pointy tops are not hollow -- so if you force a kerbal inside one he will have many issues.