Separating parts that clip through one another tends to destroy my vessel.

[PTNLemay]

To give an example of what I'm trying to do see the video here, time-stamp of around 8:41  

Matt uses a bunch of inflatable heat-shields to balance the aerodynamic drag.  We can see that the moment the parts disconnect from the ship they violently explode.  I figure this is because they can no longer use the "Same Vessel Interaction" set to no.  Once they separate, they will interact with the ship, and most importantly with one another.  Whenever I try this, the two shields bump against one another and one of the two gets flung (very quickly) back into my ship.  Usually resulting in the ship being destroyed.

Is there some special trick that Matt is using to make sure the two shields just poof out of existence before they can destroy his ship?  Because of this problem I always have to design my ships such that the heat shields never clip, which makes for a much bigger vessel to get to Eve.   

 

This is the prototype I've been trying to build.  I just want the top shields to get flung off by the time I reach the lower atmosphere of Eve.  But any time I try, with or without those sepatrons, one of the two shields will smash into the ship.  Usually destroying the payload.

 

Edited July 9, 2020 by PTNLemay

[The Flying Kerbal]

I can't answer your question, but have you thought of downloading the craft file Matt posted the link to on that video, taking it into the VAB and dismantling it to see if you can learn its secrets?

I've never managed an Eve ascent but I know in the current career I'm playing, it won't be too long before I'm offered a contract to "experience that pleasure".  So I've actually got another game going called "Craft Dissection" into which I download the craft files for as many Eve landers as possible, pull them to pieces and see what makes them tick.

This might help me build a lander which could perform the mission, but I've yet to find a way of improving my lousy piloting skills.

I know this isn't much help, but it might give you some help with your Eve lander.

[Lewie]

if you have the breaking ground expansion, use pistons to move the heat shields away from your craft before you separate them. If you don't have that dlc, experiment with radial decouplers. Those combined with structural parts will do the trick. 

the sepatrons are a good idea...maybe consider a mite or two to really get it moving. 

Edited July 10, 2020 by Lewie

[PTNLemay]

@The Flying Kerbal

Thanks for the input.  It's normal that the problem is a tricky one, it really is late-game stuff.  I was just annoyed because I have footage here of someone doing exactly what I'm trying to do.  Separate bunched up inflatables and pull it off flawlessly.

 

@Lewie

I considered pistons, but they actually use up quite a bit of power.  I'm not 100% certain (I would need to perform more experiments) but I think that the amount of power they consume is proportional to how much strain they are being put under.  So if I did construct a complicated apparatus with hinges or pistons, and it would need to hold a position while descending through Eve's atmosphere, it would start sucking up all my battery power.  I may end up doing that (and just pack on more batteries) but I'll probably just resort to a fixed structure.  My newer version looks like this.

[jimmymcgoochie]

Try the ‘deflatable heat shield’ mod, it’s a very minor config change that lets you deflate the inflatable heat shield. Robotic contraptions tend to become unstable during re-entry especially at Eve with its higher orbital velocity so deflating the heat shield makes it much easier to either discard it or keep it for later use.

[Bej Kerman]

The clipping is irrelevant. What is relevant is what part of the atmosphere and at what speed you're detaching.

[PTNLemay]

@Bej Kerman

The reason I suspect clipping is involved is because I tested my first prototype on the Kerbin launchpad.  Even without rapid atmospheric re-entry, once I decouple they spasm wildly.  Often resulting in something swinging back and smashing into the ship.  I get about 95% hit rate.  And of that about 50% of the time it takes out my payload.  So even standing still in a very tranquil state, it becomes self-destructive.

[Bej Kerman]

7 hours ago, PTNLemay said:

@Bej Kerman

The reason I suspect clipping is involved is because I tested my first prototype on the Kerbin launchpad.  Even without rapid atmospheric re-entry, once I decouple they spasm wildly.  Often resulting in something swinging back and smashing into the ship.  I get about 95% hit rate.  And of that about 50% of the time it takes out my payload.  So even standing still in a very tranquil state, it becomes self-destructive.

They shouldn't spasm. As far as the game is concerned, the parts aren't touching each other (assuming same vessel interaction is off) and the attachment nodes are a distance away. Have you tried autostrut, Kerbal Joint Reinforcement or just lots of struts?

Edit: Did you try it without clipping? Correlation =/= cause

Edited July 11, 2020 by Bej Kerman

[Ruedii]

To address your initial problem:
That is behaving as intended.  Don't do that.

As of how to prevent that:
Parts clipped together should ALWAYS be treated as a single segment when setting up staging, this means you need to set up a parent mount that ALL the clipped shields link to for this case and decouple the parent mount from the ship.

This will give you a clean decouple.

Any option to force them to self destruct after a delay will involve mods as far as I know.   I'm not sure if the sequencer part from Breaking Ground might be able to be used to create a delayed action, though.

 

 

Edited July 12, 2020 by Ruedii
Moar details: Workaround