Surface collisions on physics start
When switching to a vessel from the tracking station the ship bounces on the ground or explodes.
I've been having the issue since the 18.104.22.1681 update. It is happening all the time on my modded career save. I'd really prefer to go back to the previous release surface collisions, it was much more stable.
Attached a save game with no mods installed to check the issue, it was really easy to reproduce it.
#2 Updated by michal.rehacek over 3 years ago
This is happening to me as well, and it's worse in 1.3.1 than it was in 1.2.2. Attached is a save in which I can reproduce the problem 100%: load the save, go to Tracking Station, switch to the "Mun Tractor 2" rover (need to make rovers visible in the Tracking list first). Within a few seconds of switching to the tractor, the tractor will jump several meters into the air.
The same problem happens in bases, but the rover can repro this every time in this particular save. In 1.2.2, the rovers didn't jump much; the bases did, but Kerbal Joint Reinforcement mod was able to prevent destruction.
#7 Updated by unclejace over 3 years ago
I can confirm that this issue is ship specific. I had two ships landed on Pol within 450m of each other. After time warp, only one bounced and exploded. Ships have different components though I am unable to determine which component or parts that contribute to the bounce. Using mods KAS 0.6.3, KIS 1.7 and Docking port alignment 6.7.0
Update to this. I was able to get the ships within 80m of each other. Now the bounce and explosion does not happen! Doesn't seem to be any consistency to it.
#9 Updated by Yakuzi over 3 years ago
- Status changed from New to Confirmed
- % Done changed from 0 to 10
- Platform deleted (
I can also confirm in stock 22.214.171.1241(x64).
I also noticed that when you retract/extend the landing gear of a stationary vehicle, the wheels collide through the surface, and the craft appears to rest on the wheel axles rather than the wheels themselves. Whenever the gear is extended and locked, the craft bounces up from the axle height to the wheel height, sometimes quite violently. The change in surface interaction from axle to wheel may also be happening during loading of a save, resulting in this bouncy behaviour.
#10 Updated by Gorebane over 3 years ago
This is happening to me too. Most prominently with SSO craft with aeroplane landing gear, but also (to a lesser extent) with landing struts. Sometimes the craft just bounces high in the air, other times it just explodes. It has happened when loading a game, when exiting time warp, and when switching to a craft from the tracking station. It doesn't make any difference if the ease physics in option is enabled or not.
#12 Updated by AstroBalrog over 3 years ago
Same issue here.
I see it when switching-to landed vessels, and EVERY TIME on "rescue from surface" missions - I'll land the rescue ship a short way from the Kerbal, switch to the Kerbal, start walking towards my rescue vessel, and watch the vessel LEAP off the surface... in once instance crashing and burning.
#13 Updated by whale_2 over 3 years ago
While we're waiting for the official fix, I've made an attempt to remedy it in 1.3.1
#14 Updated by Justlooking2 over 3 years ago
Temporary fix: set textures to lowest, set physics computations to lowest, then the moment craft is loaded, activate x2 time warp (not x5). Then return to normal time. This may interrupt the bouncing. Does not fix the bug nor will it help for those craft which explode instantly on load. It may help you load a bouncy plane and retract its landing gear to prevent the bounce until the hotfix is released.
Also try the above by bringing another vehicle within 200m of the bouncing craft by using 2x time warp, then return to normal time.
#18 Updated by jclovis3 about 3 years ago
Please explain reason to change priority back to Normal. This bug makes refueling on Gilly impossible as the ship explodes coming out of warp. You can't expect to sit there for several days watching it refuel in real time. Warp must be fixed to make this playable, which makes this a critical issue. Version 1.4 is soon to be released and there should have been more than 10% progress on this by now. Nobody is going to purchase the Making History expansion if this is not fixed in the base game.
I play pure Vanilla, no mods, on Windows 10 in 64-bit mode. Started a new game with new ships so as not to reuse any old data and bug persists.
#19 Updated by BuzzKerman621 over 2 years ago
I can confirm that this issue still happens on 126.96.36.1993. This is a critical bug and should be fixed above all else. It makes base building almost impossible as vessels on the ground suddenly shoot into the air when visiting them.
For any vessels that form part of a base, I have modified the save game so that damperTweakable = 10 for all landing legs. This seems to have resolved the bouncing issues that result from the physics when coming out of time warp.
#20 Updated by BuzzKerman621 over 2 years ago
I found another workaround which doesn't require editing the save game. Instead, I set auto-struts to the root for all the docking ports which connect the base together. I discovered this after my base would explode when undocking one of the base modules. Now, I'm able to undock safely without the base tearing itself apart.
#21 Updated by [email protected] over 2 years ago
The start-up problems with the physics simulation for landed craft were fixed in 1.4.1.
That is, the save-file attached at the top of the report shows only a 1/4 meter settling when we first switch to the craft, or when we come out of 'on-rails' time-warp.
Possibly the confirmation above for versions after 1.4.1 refers to
the jumping we had before version 1.5 when docking/undocking/command-chair-exiting, #19343 #19402 #19474
or the smooth bouncing we have with #17830 #19427 #19491
or maybe the kick you can get when bottoming out the landing legs or landing gear #20682
Whale_2's mod addresses the initial physics-startup, and you can see at his thread linked above that he is surprised that people want the mod for KSP versions 1.4+.
If anybody still sees a jump upon the initial load of physics, they should attach a craft file that shows the problem, because the original example no longer shows any problem.
#24 Updated by Yakuzi about 2 years ago
The issue seems to trigger substantially less frequent in KSP 188.8.131.523(x64), I did experienced it once however with a parked craft after stopping 100x time-warp (haven't been able reproduce it though). The craft bounced up violently and the brakes didn't work afterwards (even after switching them off and on again), resulting in the craft sliding off the runway.
#25 Updated by [email protected] about 2 years ago
- Status changed from Ready to Test to Resolved
- % Done changed from 80 to 100
I retested the save from the original report, and it still shows only one 1/4-meter bounce -- much better than version 1.3.1 and the same since version 1.4.1
It seems the best way to handle the cases where "the issue still happens" is to open another bug with another example file.