Avoiding cataclysmic base syndrome?

[kfsone]

I've just spent the last few days building-up a mining base on minmus so that I could ferry ore or fuel up to an orbiting transit station. After taking a short break, I load the game back up and ... it seems like I saved just as a small black hole passed my station; switching to the base is absolutely 100% concretely guaranteed to fling it up a few dozen meters above minmus's surface in a severe spin that slam big chunks of it into the ground at 100s/m/s, trashing it.

Is there a trick, setting, or mod I can use to salvage this and pin it back to the ground or something?

Is there a trick, setting, or mod I can use to stop this happening in the first place?

It's happened to me with/without mods, and at the moment I have a fair number of mods installed. I don't know if maybe the original problem was fixed at some point and now my modlist is making it break again?

Save game: https://www.kfs.org/oliver/ksp/quicksave.sfs (the base is "Lander X" on Minmus).

I've tried backing out all the mods that aren't actively used for parts in the base - but, again, this happened to me without mods too. I've tried switching to the other lander, I've tried turning changing sas settings as soon as I get in, I've tried landing another vehicle nearby. As soon as the base loads, BOOM, off it goes.

--- edit: mod list when it happened this time:

[x] Science! Continued (xScienceContinued 6.0.0.9)
Astrogator (Astrogator v0.10.3)
B9 Part Switch (B9PartSwitch v2.20.0)
Breaking Ground (BreakingGround-DLC 1.7.1)
ClickThrough Blocker (ClickThroughBlocker 1:0.1.10.17)
Community Category Kit (CommunityCategoryKit v5.2.0.0)
Community Resource Pack (CommunityResourcePack 1.4.2)
Community Tech Tree (CommunityTechTree 1:3.4.4)
Contract Configurator (ContractConfigurator 1.30.5)
Contract Pack: Field Research (ContractConfigurator-FieldResearch 1.2.2)
Deployable Engines Plugin (DeployableEngines 1.3.1)
Distant Object Enhancement /L (DistantObject v2.1.1.7)
Distant Object Enhancement /L default config (DistantObject-default v2.1.1.7)
Dynamic Battery Storage (DynamicBatteryStorage 2:2.2.5.0)
Editor Extensions Redux (EditorExtensionsRedux 3.4.3.5)
Engine Lighting Relit (EngineLightRelit 1.6.3.2)
EVA Refueling (EVARefueling 0.1)
Firespitter Core (FirespitterCore v7.17)
Harmony 2 (Harmony2 2.0.4.0)
Hide Empty Tech Tree Nodes (HideEmptyTechNodes 1.3.0)
Kerbal Attachment System (KAS 1.10)
Kerbal Dust Experiment (KDEX v2.0.2)
Kerbal Engineer Redux (KerbalEngineerRedux 1.1.9.0)
KSP Community Fixes (KSPCommunityFixes 1.12.1)
LoadingTipsPlus (LoadingTipsPlus V1.9)
Making History (MakingHistory-DLC 1.12.1)
Malemute Rover (MalemuteRover 1.4.0)
MechJeb 2 (MechJeb2 2.14.1.0)
MechJeb and Engineer for all! (MechJebForAll 1.3.0.7)
Mission Controller 2 (MissionController2 2:3.2.0.0)
Module Manager (ModuleManager 4.2.1)
Near Future Electrical (NearFutureElectrical 1.2.3)
Near Future Electrical Core (NearFutureElectrical-Core 1.2.3)
Near Future IVA Props (NearFutureProps 1:0.7.1)
Near Future Launch Vehicles (NearFutureLaunchVehicles 2.2.0)
Near Future Propulsion (NearFuturePropulsion 1.3.5)
Near Future Solar (NearFutureSolar 1.3.2)
Near Future Solar Core (NearFutureSolar-Core 1.3.2)
Near Future Spacecraft (NearFutureSpacecraft 1.4.3)
Part Wizard Continued (PartWizardContinued 1.3.9)
Patch Manager (PatchManager 0.0.17.3)
PlanetShine (PlanetShine 0.2.6.6)
PlanetShine - Default configuration (PlanetShine-Config-Default 0.2.6.6)
Procedural Fairings (ProceduralFairings 1:v6.2)
Procedural Parts (ProceduralParts v2.3.0)
PWB Fuel Balancer Restored (PWBFuelBalancerRestored 0.2.1.7)
RCS Build Aid (RCSBuildAid v1.0.6)
ReStock (ReStock 1.4.3)
ReStock+ (ReStockPlus 1.4.3)
Rocket Sound Enhancement (RocketSoundEnhancement 0.7.2)
Rocket Sound Enhancement - Default (RocketSoundEnhancement-Config-Default 1.0.2)
SCANsat (SCANsat v20.4)
ScienceAlert ReAlerted (ScienceAlert 1.9.10)
SimpleFuelSwitch (SimpleFuelSwitch 1.4.1)
Smart Parts (SmartParts 1.9.16.2)
SpaceTux Library (SpaceTuxLibrary 0.0.8.4)
StageRecovery (StageRecovery 1.9.5.4)
The Janitor's Closet (JanitorsCloset 0.3.7.8)
Toolbar (Toolbar 1:1.8.0.7)
Toolbar Controller (ToolbarController 1:0.1.9.6)
Trajectories (Trajectories v2.4.3)
Transfer Window Planner - Fork (TransferWindowPlannerFork v1.9.0.1)
USI Tools (USITools 1.4.0)
Utility Weight (UtilityWeight 2.0.0)
Waterfall Core (Waterfall 0.8.1)
Waypoint Manager (WaypointManager 2.8.3.3)
Zero MiniAVC (ZeroMiniAVC 1:1.1.2.4)
 

Edited April 24, 2022 by kfsone

[Admiral Fluffy]

If you are using one of the newer versions, you can use a ground anchor. Other than that, I don't know.

[Dman979]

Moved to Technical Support (modded).

[miklkit]

I'd say that base isn't quite heavy enough to stop it from flying off.   My Minmus base doesn't launch but anything smaller needs to be anchored or it flies off (220 meters or so) or simply explodes.  Ground anchors do actually work.  At one time there were 7 rovers there but the others all exploded.

[kfsone]

At the time, it was pretty heavy - all the fuel tanks were full and all the ore tanks were full. But maybe there's some kind of simplification algorithm that spreads the weight out over the bounding box of the base, and since it's L-shaped the massively reduces the weight/m2.

That said - I figured it out and was able to fix it. I happened to have 40 QA/CI machines idling, so I ran a lot of different combination tests and found one specific pattern that fixed it and allowed me to recover, but it has to be done in a single game session:

- modify the save: set all the parts to "rigidAttachment False",
- load the save, now explodes like a scene from Gravity too, wait 90s,
- re-modify the same save: set all the parts to "autostrut Off",  sas modules to "wheelAuthority 1" (%1),
- load, as above but now looks like one of the secondary-collision scenes, wait 90s,
- re-modify the same save: set all the parts to "rigidAttachment True",
- load, back to the original flip & smash, wait 90s,
- re-modify the same save; set all the parts to "autostrut Grandparent",
- load
-> fixed
- save, quit ksp, restart
- load
-> still fixed

when I say "load" I don't mean quit the game, I mean: the equivalent of hit-escape and select 'load' -> 'quicksave'. 

Able to recover the same save game now twice by repeating those steps (the timing is totally approximate, just wait until the big chunks have settled). Possibly there's an invalid value in the save that induces some buggy behavior that doesn't get cleared out properly between reloads, but - again - this is what happened to me way back in the day when I built my first modless minmus base in my first game

Edited April 25, 2022 by kfsone

[DeadJohn]

Here are some ways you might try rescuing that base. Make sure you have a backup save of your game before trying any of this.

1. Quickly turn on timewarp as soon as the base is airborne, and immediately turn it off again before the base crashes into Minmus. That will stop the base's rotation and with some luck the base might land safely. If it doesn't work reload and try again.
2. The HyperEdit mod has a "land here" function. Use it while the base is airborne. If it lands upside down, reload and try again.
3. Let the base crash, create a new save file, then edit that file to flip the base upright and un-break the panels. This is a last resort when you can't find an easier fix.

That will rescue your base but it might continue to happen every time you transfer back to the base. Possible causes:

1. I can't see if you have any spring-loaded landing gear in the video. Springs can compress too much during timewarp or while transferred away from your base, the legs expand when resuming normal physics, and Minmus' low gravity is weak enough to let the base lift off. Customizing leg settings for damping and spring strength on an existing base can reduce the problem. If building a new base on Minmus, use unsprung parts such as structural girders and base legs from Near Future.
2. I also can't see what docking ports you have. The grabber, klaw, and similar parts flex and can trigger KSP glitches. Near Future has 2  sizes of telescoping grabbers that hold pretty well. Regular docking ports on each side are safest IMO but awkward to connect on a surface.
3. Attaching parts during EVA construction can sometimes cause phantom forces that accelerate a vessel into a spin. That doesn't look like what's happening to you, but if you've used EVA construction maybe reattach those parts.

[kfsone]

10 minutes ago, DeadJohn said:

1. Quickly turn on timewarp 
2. The HyperEdit mod 
3. Let the base crash, create a new save file, then edit that file to flip the base upright and un-break the panels. This is a last resort when you can't find an easier fix.

Awesome on 1 and 2; above awesome on 3. I wrote my own save-file editor donkey years ago and I added rigid/autostrut options to this weekend to see if I could fix this, but I totally overlooked #3 - brilliant.

10 minutes ago, DeadJohn said:

That will rescue your base but it might continue to happen every time you transfer back to the base. Possible causes:

1. I can't see if you have any spring-loaded landing gear in the video

None - but while I was checking, I have a lander parked next to it and I noticed the landers now have a "tether to ground" option. Maybe I should add some so I can use that

10 minutes ago, DeadJohn said:

1. I also can't see what docking ports you have. The grabber, klaw, and similar parts flex and can trigger KSP glitches. Near Future has 2  sizes of telescoping grabbers that hold pretty well. Regular docking ports on each side are safest IMO but awkward to connect on a surface.

Clamp-o-tron jr. Thinking about it, one of the last changes I'd made was adding EVA mounting KAS TJ-2 so that I could land a shuttle reasonably close and then extend that out instead of trying to dock (which is funny, because in order to do so I had to land a little rover and dock that)

10 minutes ago, DeadJohn said:

1. Attaching parts during EVA construction can sometimes cause phantom forces that accelerate a vessel into a spin. That doesn't look like what's happening to you, but if you've used EVA construction maybe reattach those parts.

Ah, a LOT of it is eva assembled. If re-mounting them can fix it, that leans in to my theory that there's some bad data accumulating in saved files and causing buggy behavior in the game proper, which was why I ended up investigating "what if I try changing different properties between saves" 

 

Awesome answer, lots to chew over.

 

[DeadJohn]

5 minutes ago, kfsone said:

Ah, a LOT of it is eva assembled. If re-mounting them can fix it, that leans in to my theory that there's some bad data accumulating in saved files and causing buggy behavior in the game proper, which was why I ended up investigating "what if I try changing different properties between saves" 

You can test for phantom forces from EVA construction or autostrut by saving your game, cheat your base into orbit with alt-f12, then watch to see if the base spins faster and faster, or the orbit changes, or the base deforms in zero G. Then reload your save to undo the teleport.