BUST: Docking Ports Won't Dock/Undock

[Claw]

Bugs Under Special Test (BUST)

Docking Ports Won't Dock/Undock

This thread is part of a series of community efforts to find the root cause of some of the more difficult to pinpoint bugs in KSP. The purpose of this thread is to for users to collaborate on solving the root of the problem.

Please see here for more details before posting.

Special Note: Please do not post requests for support on this thread. If you need help fixing a problem, please see the other Support stickies linked below.

Known Issues and Self Help

Support Request and Bug Reporting Guide

---

Purpose of the BUST threads:

• The BUST threads exist for discussion of the specific topic and for organization of the community of players who are collaborating to dig into the issue. The threads do not exist to answer support requests and any posts for support requests will likely be moved out of the thread.
  
• If you are familiar with the Bug Reporting Guidelines, what we are trying to do is solve the "How to replicate" portion of the bug report.

The ultimate goal of a BUST thread is to end up with a solid bug report that has easily repeatable steps. So if you post information, try to post clear directions on how you came up with it.

---

Topic:

Stubborn docking ports that refuse to dock (or undock).

Description:

Sometimes no matter how much you bump the docking ports together, or click on the decouple button, those darn docking ports just don't want to do what they're told.This bug strikes at random, and can cause the docking ports to become unresponsive.

Primary Known Issue Threads:

http://forum.kerbalspaceprogram.com/threads/78863-FIX-Dock-Undocking-Bug-in-0-23-5

What's known:

I know a lot about the structure of the craft, how KSP decides to label things, and how to fix this problem. However, I know very little to nothing about what actually triggers it. I've often seen this in conjunction with the docking alignment mod, but I think it also happens without the mod.

Edited November 16, 2014 by Claw

[Kedwin Hubble]

I ran into this bug in my current 0.90 modded career save. The bug occurred while launching a station to fulfill a "build an orbital station around Kerbin" contract. I had two set of docking ports on the craft that got stuck and would not undock. Both docking ports were linked to action groups to undock -- this may have caused the bug, but am not sure yet. Here is the craft file. I was playing with the following mods:

Active Texture Management

Astronomer's Performance Improvement

KSP Add-on Version Checker

Blizzy's toolbar

Kerbal Engineer Redux

Kerbal Alarm Clock

Trajectories

Deadly Reentry

FAR

Procedural Fairings

Kerbal Isp Difficulty Scaler

Kerbal Joint Reinforcement

Real Chute

Remote Tech

SCANSat

TAC life support

Dmagic Orbital Science

Universal Storage

Kerbal Attachment System

USI Kolonization Systems MKS/OKS

Contracts Window +

Contract Configurator

Contract Pack: Remote Tech

Contract Pack: SCANSat

Chatterer

Precise node

Eventually, this fix got the stuck docking ports unstuck.

I'm going to see if I can reproduce the bug and will provide any logs or other useful information, if I can.

Edit:

So I was able to reproduce the bug by doing the following:

1. Start new sandbox save with the mods listed above.

2. Quit KSP.

3. Copy paste craft file above into the new sandbox save's folder.

4. Load sandbox save.

5. Load Skylab craft.

6. Launch.

7. Use first stage to get apoapsis above 100 km

8. Trigger staging to decouple SRBs and ignite second stage.

9. Circularize and cut engines.

10. Press 1 for saved action group to undock docking port connecting main craft and second stage.

Docking port now stuck together even though should be undocked. Vigorous shaking, rotating, thrusting, etc. will not get unstuck.

Here is the output log after reproducing as such. I've made a backup copy of the entire KSP folder as it existed right after reproducing this bug, so I can send any other files that might be helpful as well.

Edited January 31, 2015 by Kedwin Hubble
reproduced bug