1.12 Autostrut - changes

[mikegarrison]

On 7/6/2021 at 9:12 AM, teelaurila said:

Basically every station I built has become a huge pain to dock to because of all the wobblyness. And every larger mission ship a pain to control.

This has always been a KSP problem. It's very fundamental to the way the game physics are handled. The basic problem is that you can have snap-together "lego" ships or you can have rigid ships, but it's hard to have both.

This is why Kerbal Joint Reinforcement was made, to massively stiffen up the points between parts. It did (does?) have some other consequences, but it certainly took most of the wobble out.

It's why spamming struts is a thing.

I don't use autostrut because I don't trust invisible struts that I don't place. I used to use KJR all the time, though. I'm not sure it's still compatible with the latest versions.

[Cavscout74]

13 hours ago, mikegarrison said:

I used to use KJR all the time, though. I'm not sure it's still compatible with the latest versions.

As of 1.11 (?) it didn't work correctly.  Most things still worked, but it caused issues with the construction mode and the MH round pods - when you decoupled the pod, it stayed "attached" to the base by what felt like an invisible rubber band.  Went through a reentry with the spent stage staying exactly the same distance (~400m IIRC) from the pod the whole way, including floating in the air above the pod after splashdown.  I haven't checked back in a while, so I don't know if the KJR folks ever were able to work it out.

[pquade]

On 7/6/2021 at 10:45 AM, teelaurila said:

Do try that 'roid. Klaws seems to work a bit better than ports. And turning slowly probably shouldn't be a huge problem. Beside, you can always stop rotation with a time warp.

Couldn't put it off any long and finally had to just bite the bullet and grab it.

For the record, the "Advanced Grabbing Unit" is, from what I can see, no better than the standard sized docking port WRT the wobbly joint issue, and considering the masses involved here this is all very delicate.  In order for my asteroid harvester to stay in one piece, I've had to shut off all my reaction wheels except one and on that remaining reaction wheel turn its authority down to 15%.  Even at that the entire craft and asteroid wobble considerably, but just below the threshold for it to go out of control and explode.

I also got lucky and ended up with a magic asteroid, which I know can be cheated by repeatedly restarting to prior to entering physics range but I've never done that and after years and years of playing and dozens and dozens of asteroids harvested this is actually my first magic asteroid.

Here's what the entire thing looks like;  

Now very slowly performing the capture burn.  throttle is burning that single nuke engine at less than 0.00m/s since the entire craft can't be trusted and I need to burn off more than 61m/s in order to get my Kerbin capture.

This is going to take awhile.

Edited July 16, 2021 by pquade

[teelaurila]

On 7/16/2021 at 10:52 PM, pquade said:

  Even at that the entire craft and asteroid wobble considerably, but just below the threshold for it to go out of control and explode.

Are you using SAS? Because it seems one really should not under present circumstances with complex craft. Give the thing some angular momentum manually, and then manually slow it down to meet your burn marker. That's how I  now somehow manage most burns - it's doable long as you're not trying to land.  You will not be able to burn exactly to the right direction, but fluctuating around the right direction, with decreasing acceleration as necessary, has let me converge burns to pretty much exact. But with much hassle.

When SAS is off, the wobble should be slowing down.

Another trick to help a bit is to move control point as close to the com as possible, as then the attitude will not wobble as much, helping possibly greatly with the feedback loop that causes the wobble.

On 7/15/2021 at 9:11 AM, mikegarrison said:

This has always been a KSP problem. It's very fundamental to the way the game physics are handled. The basic problem is that you can have snap-together "lego" ships or you can have rigid ships, but it's hard to have both.

Yes, if you insist your "lego" pieces are the rigid blocks that are set from the start. One should be able to form large rigid objects that have simple single-body dynamics by "re-meshing" snap-together parts as necessary. It is still possible to analyse impacts, and even stresses within the mesh, so as to again break it if under too much punishment. I truly hope they go that path with KSP2. That would likely necessitate "calculation breaks" when ships merge or break, but that is a cosmetic flaw compared to the difficulty we now have in working with large craft.

[pquade]

6 hours ago, teelaurila said:

Are you using SAS? Because it seems one really should not under present circumstances with complex craft. Give the thing some angular momentum manually, and then manually slow it down to meet your burn marker.

I'm not sure how much experience you have with asteroids, but large ones like this do not turn quickly even in the best of circumstances.  As it was, this was a 5.8 hour long burn just for a little under 61Dv.  This would take literally weeks of real time if done your way and waiting for the asteroid to occasionally and randomly rotate into "good enough" attitude.

Yes, SAS was on, just had all reaction wheels turned off except one and that one was set to 5%, and the engine at 5% as well.

You're going to have to trust me when I say I know what I'm talking about here.

Edited July 21, 2021 by pquade

[Wilds]

Yeah, my station turns into a bendy mess when doing 4x time warp or with a decent TWR. Doesn't happen on my older copies of Kerbal. I'm used to using BetterTimeWarp with high physics time warp. That is definitely off the table until this gets fixed.

I sure love my autostrut. One thing I was thinking about was taking a lot of strut parts into inventory and welding them on and back off when needed.

[OskieWoskie]

I rely way too much on autostrut as I like to keep my stations in a certain orientation with Kerbin using the auto-SAS. Now when I even load the stations they wobble to death even if I disable all the SAS modules including capsules and probes.

[Serenity]

Haven't even launched the game for this exact reason, me and my autrostruts go a long way back, no way i am playing without them and also don't want to miss the new content, so no Kerbal for now  .

Edited July 28, 2021 by Serenity

[DeadJohn]

On 7/15/2021 at 3:27 PM, Cavscout74 said:

...I haven't checked back in a while, so I don't know if the KJR folks ever were able to work it out.

I think it's still broken. KJR (Next and Continued forks) began having issues with 1.11 and as far as I can tell from their forum threads have not been updated. Additionally, the workaround of reverting to autostruts instead of KJR is no longer compatible with 1.12 because autostruts can't span the revised rotating docking ports.

AFAIK the "best" solution requires manually re-attaching struts with an engineer after each docking. That becomes an extreme amount of effort.

[Anth]

In 1.11 and 1.12 so far you will have issues with attaching physical struts. [edit] Because they will detach on being reloaded

If you attempt to do so:

1. Put a physical strut into the container of the docked ship. This causes the physical strut to change its ID what the container's ID is
2. Then when using EVA construction grab the physical strut from the container of the docked ship (don't put it into the Kerbal's container)
3. Then place onto the station then back onto the ship

Also. Keep the SAS of the station off. It causes the station to wobble, and if RCS is on at the same time its 10 times worse.

If you need to keep SAS on to reorientate the craft keep using timewarp to stop the wobble.

NOTE:

DONT save the game if the craft is bent out of shape.

Due to the Rotating Docking Drift that came with 1.12 if the station is bent and then saved, on reloading it will be permanently bent.

Edited July 29, 2021 by Anth12

[TheDicko]

Any updates on this? Damn annoying bug.

[pquade]

5 hours ago, TheDicko said:

Any updates on this? Damn annoying bug.

Latest patch out today appears to have fixed the issue.

Docking ports now have the ability to lock or unlock rotation.  In the locked position (default when you first reload after upgrading), auto struts pass through docking ports.  Just upgraded and checked it all out.  Seems to be working as advertised.

I'm happy!

On 6/30/2021 at 3:19 PM, JPLRepo said:

Watch out for the next patch.

Thank you and thank the team for fixing this!  Seems to be working great!