Bug #25775

Mobile Processing Lab - Kerbals on one ladder fail to transition to ladders on attached parts

Added by kayelem 8 months ago. Updated 7 months ago.

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Kerbals on one side of the MPL (adjacent to the flag) can be moved to ladders on attached parts smoothly and easily.

Kerbals the other side of the MPL can be moved to ladders on attached parts with difficulty, changing orientation and direction just at the point one would expect them to smoothly transition from one ladder to the other.

Steps to replicate:

  • Start new sandbox game
  • Enter the VAB
  • Place a PPD-10 Hitchhiker Storage Container
  • Select a Mobile Processing Lab MPL-LG-2
  • Rotate the MPL about its vertical axis by 180 degrees
  • Place this MPL on the bottom of the PPD-10
  • Place a second PPD-10 on the bottom of the MPL
  • Add a Kerbal or two to the MPL
  • Launch
  • Click on the MPL hatch on the same side as the PPD-10 hatches
  • EVA a Kerbal
  • Move the Kerbal up or down, towards either of the PPD-10 hatches

Expected Behaviour:

The Kerbal smoothly transfers from the MPL ladder to either PPD-10 ladder, remaining upright.

Unexpected Behaviour:

The Kerbal gets to a PPD-10 ladder, turns upside-down, changes direction and (more often than not) remains on the MPL ladder.

Moving the Kerbal from the MPL ladder to either of the PPD-10 ladders can sometimes be achieved, after multiple repeated attempts (and what looks like a bizarre gymnastics routine.)

Additional Note:

If the above construction steps are followed, omitting the 180-degree rotation of the MPL, Kerbals transition between ladders as expected. The unexpected behaviour only manifests on the side of the MPL opposite the flag location.

This suggests that the ladders on opposite sides of the MPL differ in some way, counter to expectation.

MPL Test 1a.craft (6.57 KB) MPL Test 1a.craft on which Kerbals behave oddly on ladders kayelem, 07/14/2020 02:13 AM
MPL Test 1b.craft (6.56 KB) MPL Test 1b.craft on which Kerbals behave as expected on ladders kayelem, 07/14/2020 02:14 AM
MPL Test 2a.craft (19.1 KB) MPL Test 2a.craft kayelem, 07/14/2020 03:03 AM
MPL Test 2b.craft (19.6 KB) MPL Test 2b.craft kayelem, 07/14/2020 03:03 AM
Eveolution-Pt I.craft (530 KB) Eveolution-Pt I.craft hihosilver28, 07/27/2020 12:25 PM


#1 Updated by kayelem 8 months ago

The unexpected ladder behaviour can also be demonstrated with the second attached craft, which differs only slightly from the first, in that the ladders adjacent to the MPL have been rotated slightly away from vertical.

MPL Test 2a.craft
  • Kerbals exiting from either hatch move between ladders smoothly
MPL Test 2b.craft
  • Same craft as 2a with the ladders adjacent to the MPL rotated by 5 degrees
  • Kerbal on ladder adjacent to flag moves between ladders smoothly
  • Kerbal on ladder opposite flag exhibits unexpected behaviour

#2 Updated by Robert.Keech 8 months ago

  • Status changed from New to Confirmed
  • % Done changed from 0 to 10

#4 Updated by hihosilver28 7 months ago

I encountered the same issue with the ladders. In my case it seemed to affect whether the ladder was in the "standard" orientation or "upside-down". When the Kerbal encountered a ladder that was "upside-down" the Kerbal would flip. In the attached craft, the very first ladder below the command pod displays this behavior.

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