odd docking behavior

[AlamoVampire]

Okay, I do not understand this one. Until today I have had no real issue with docking anything with the help of MechJeb. Today, I launch an interplanetary ship core with no real issues. I get it into a 100 by 100km orbit no sweat. I go to launch the first of 4 cruise stage fuel/nuclear engine components and all hell breaks loose. The thing gets into orbit just fine, I get it into the same 100 by 100 km orbit just fine. As soon as it finishes its final burn to circularize I engage the rendezvous planner and autopilot, it goes to work, matches the inclinations just fine, sets up a Hohmann Transfer just fine, and starts to close for an intercept. The odd and hateful hell is when I get to about 20km out, the targeting sensors come on and show my range and even turn on the target relative velocity indicators like normal. The thing starts to do its burns and what not, and then I see it, my relative speed is not decreasing even with my rockets exhaust pointed right AT my target, its increasing, but, my distance is closing, so I figure, its just a glitch in the display. I get to 500m then 450, then 400 and so on, then it happens. The target suddenly is increasing in distance from me, 450, 500, 1km and so on, then at 5km from me, it suddenly warps to a million or MORE KM ahead of me. I hit the button to get closer and this idiotic dance repeats, this time, I get to about 200m distance then the target whizzes away and I am left with no fuel and a strong desire to cry, because at this point I have spent 2 HOURS trying to dock 1 of 4 modules to a ship.

Edited August 31, 2013 by AlamoVampire

[Sirine]

Check if your battery is dead.

[sojourner]

Not sure what caused your problem, but why didn't you just use the "launch to rendezvous" option on the ascent autopilot? would have been a lot quicker and you could have gone straight to docking autopilot when it finished. No rendezvous autopilot needed.

Is it possible you are using some other mod that is conflicting with mechjeb? Anything new on these 2 ships you haven't used before or haven't used together?

[lockpicker]

Something about the same happened to me. Don't know about you but if your relative velocity starts destabilizing wait for it to stabilize,don't plan any manuevers. So i waited for my relative velocity to stabilize again and retried, it worked then. However the relative velocity for me went from the real velocity,to zero then to about 4k and then back to the real velocity.If i remember correctly it took about 10 mins to stabilize (plus, i do think there was a bit of luck involved).

[AlamoVampire]

battery power was not the issue, had 4 giant solar panels out + 4 of the 400 rechargables on the thing. I do use launch to rendezvous, but it always ignores me and goes into a full circle orbit, which I find odd, but, it seems to work, usually. After waiting about 10-15 minutes from that cluster bang of a mess, I relaunched into a 212 x 212km orbit, and it worked like a charm. cruise stage 1 now docked, part count is going up, gonna hurt frames badly at some point lol. only 2 mods I use are Mechjeb and romfarers lazor docking cam, and both never seem to conflict...

edit: while, yes, at this moment, I managed to finally dock part 1 of 4 of my cruise stage engines and tanks, I will leave this as unanswered to get more input from as many people to see if this is a bug or what not.

[AlamoVampire]

just an update to any who may be following this, the second cruise/fuel stage has been docked on upping it to now 300 parts and like 200 tons give or take... this is just getting ugly, a final product shot will show up at some point also, during this most recent docking, I did not observe the odd behavior mentioned in the op

[Johnno]

Okay, I do not understand this one. Until today I have had no real issue with docking anything with the help of MechJeb.

Since this seems to be a MechJeb issue you'd be better off asking in addon support / its specific thread. Also it'd be rendezvous, not docking you're having an issue with. Have you been able to reproduce this issue on a stock install? (ie do you know how to rendezvous without MJ?)

Other than that all I can say is check your map next time to see if/how your orbits change.

[MrPopcup]

Yes, Try to dock without MechJeb and use the map, docking isn't hard, it just takes time and need a patient person.

[KerbMav]

There is another thread that reads familiar?

http://forum.kerbalspaceprogram.com/showthread.php/38268-How-to-avoid-weird-relative-target-velocity-speed-glitch-when-entering-visual-range

[AlamoVampire]

it isnt MechJeb that caused this, as, mechjeb got me to a rendezvous, it was once I was in docking range, or rather nearing docking range that all hell broke lose, but, to answer you guys on how I do it w/out mech jeb, the answer is simple: I have only done so ONCE w/out it, and then, it was a royal cluster fail of screaming past my target vessel and not being able to zero out velocities, which, necessitated getting mechjeb lol. But, again, the glitch has NOT reproduced itself YET since I now have 2 cruise and fuel stages docked to my target vessel, just need 2 more then off to Jool. I will launch a test save and try a manual docking again to see if it duplicates w/out mechjeb on either vessel and report back success or failure or something in between.

[AlamoVampire]

okay guys, I know this is a "simple" thing once you learn how to do it, but, holy cow! I just made a test save to see if I could manage a mechjeb free rendezvous and docking and, well, a direct launch to rendezvous later here I am!!

no real issues came up, not even that odd glitch this threads about...

[Johnno]

it isnt MechJeb that caused this

I have only done so ONCE w/out it, and then, it was a royal cluster fail of screaming past my target vessel and not being able to zero out velocities, which, necessitated getting mechjeb

I'd say that these two statements are mutually exclusive. Unless you know how to manually rendezvous you won't know what to look out for when you experience 'glitches', thus you can't rule out MechJeb errors.

Unless you can reproduce the issue in a completely stock install we can't be sure that it's an actual game issue. Even then we'd need the current persistent file / quicksave plus logs to be able to rule out everything else.

There have been issues with MechJeb before, like the autostaging of parachutes on re-entry. As great of a tool as it is, unless you know how to do stuff manually it's a bit futile asking for assistance about general gameplay if you're using MechJeb, which is why I recommended the addon section.

Edited August 31, 2013 by Johnno
typo