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[PART, 1.0.2] Anatid Robotics / MuMech - MechJeb - Autopilot - Historical thread

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NASA and other Earthly rocket launchers do exactly that. They wait until the time when the target orbit and the launch site are at the proper coincidence in order to use the least amount of reaction mass. Launch windows.

To launch to ISS required a northerly "dogleg" to reach the orbit of the ISS which is inclined to the degree it is so that it will pass over Russia's launch site. Most other Shuttle launches angled to the south in a mostly straight path that was more efficient from Canaveral's 28.4556° N latitude.

That's why Columbia didn't go to ISS, it was too heavy to carry a useful payload to the station even with the super lightweight external fuel tanks. Which is what led to its demise due to flying with an old "lightweight" tank on its last mission instead of one of the newer tanks with revised and fresher insulation.

Uh, flying with one of the newer tanks still wouldn't have saved it if a chunk fell off and hit in a bad place since the root problem would still be there.

This isn't the thread to discuss it though.

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Is it just me, or does the latest version of MechJeb not handle asparagus staging and drop tanks as well as previous ones did? My current launcher uses a Skipper on an orange tank as it's primary booster, but since the payload uses radial engines, it fores those off at the same time with fuel pipes to them from the orange tank. I recall that previous versions of MechJeb would handle this correctly, showing the first stage with the combined thrust and delta-v of all the engines, and then the next stage, after the booster and orange tank are decoupled, with the thrust and delta-v of the payload running off its own internal fuel. But now it shows all the delta-v in the first stage and 0 in the second, as if it were assuming that the empty tank would not be jettisoned until all the engines were dead.

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Screenshot of your ship maybe (and craft file maybe)? and also double check your staging and fuel lines. I haven't had any issues with MJ and asparagus staging at all.

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I can screenshot it next time I'm playing. I know my staging and fuel lines are correct, though, because they design does work in practice. Hell, it even autostages correctly! It's just the delta-v window that is wrong.

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the latest version of MechJeb

The latest official release, dev version ? I can't help without proper info.

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Dev build 467 seems to solve the Problem with the rendevous planer/node execution. Thanks a lot.

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Just dropping in to say thank you for this mod. Although I only started playing after the 1.0 release, I would have already stopped if I had to launch, circularize and rendezvous every single orbit and craft by hand - or to be more precise, the deprecated, simplistic MechJeb the vanilla KSP system actually is.

Thank you for making and maintaining this mod and thus taking all the unnecessary tediousness out of the game.

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Sarbian,

I just want to chime in and tell you what a great addition to KSP MechJeb is. Even though I am having a lot of functional issues with MJ currently I don’t even want to bother you with those, as I know it will all work out eventually. Thanks for your contribution, it is appreciated.

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Does anyone here have the config that added MJ to all command pods?

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Does anyone here have the config that added MJ to all command pods?

Sure. I assume you know how to set up the config? If not, it's easy, just paste the below code into notepad and save it as <whatever you want>.cfg into the gamedata folder.


@PART
[*]:HAS[@MODULE[ModuleCommand],!MODULE[MechJebCore]]:Final
{
MODULE
{
name = MechJebCore
}
}

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how can i modify Mechjeb so i can be used in career from beginning?

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how can i modify Mechjeb so i can be used in career from beginning?

The code I just posted is one method since that bypasses the research requirements.

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I have a question. Mechjeb has decided that it will no longer execute any maneuver node after launch to circularize at the top of an orbit. I don't understand why- the ascent module gets it perfectly off the ground, lined up, and then gracefully dips past to slam into Kerbin again.

I've tried every option in the Ascent module AND have tried using the maneuver planner directly to circularize- in both cases it gliiiides right past.

Any idea what's causing this and how to STOP it?

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Is this normal for MechJeb (build 468)? I saw it when I was looking around at the new staging and deltaV info. I don't usually make planes (or spaceplanes for that matter), so I'm not used to reading the deltaV off of jet engines. I do know that the ISP of jet engines are different from rockets because 1/6th (I think, fraction might be wrong) of it is fuel, the rest is air.

I did check back in 467 briefly and the numbers looked the same there.

screenshot2_zpsdopwi5up.png

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NASA and other Earthly rocket launchers do exactly that. They wait until the time when the target orbit and the launch site are at the proper coincidence in order to use the least amount of reaction mass. Launch windows.

To launch to ISS required a northerly "dogleg" to reach the orbit of the ISS which is inclined to the degree it is so that it will pass over Russia's launch site. Most other Shuttle launches angled to the south in a mostly straight path that was more efficient from Canaveral's 28.4556° N latitude.

That's why Columbia didn't go to ISS, it was too heavy to carry a useful payload to the station even with the super lightweight external fuel tanks. Which is what led to its demise due to flying with an old "lightweight" tank on its last mission instead of one of the newer tanks with revised and fresher insulation.

No they didn't do exactly that, all they did, and all current resupply/crew transfer missions do, is launch into the plane and then use a few orbits to rendezvous like a normal rendezvous. They do not launch to rendezvous in an inclined plane.

The fastest launch to rendezvous that I can find was Soyuz 34/TMA-08M taking 6 hours and 4 orbits.

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No they didn't do exactly that, all they did, and all current resupply/crew transfer missions do, is launch into the plane and then use a few orbits to rendezvous like a normal rendezvous. They do not launch to rendezvous in an inclined plane.

The fastest launch to rendezvous that I can find was Soyuz 34/TMA-08M taking 6 hours and 4 orbits.

Of course, if you aren't trying to make a zero-zero rendezvous, launching to intercept becomes easier. But that's not useful for docking, because you would have to burn a massive amount of delta-v to match velocities. (Sometimes you want to make an intercept and have no interest in matching velocities -- ASAT weapons, for instance.)

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Hi, just wanted to confirm to sarbian that build #467 fixed at least all of my node execution problems. I do not use ascent guidance, since it is still locked in my tech tree, but after taking off, all node executions in my trips are now warping nicely to the correct position and the node burns are handled automatically. Beautiful, nice job!

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The fastest launch to rendezvous that I can find was Soyuz 34/TMA-08M taking 6 hours and 4 orbits.

The fastest was Gemini XI doing the rendezvous with an Agena target on the FIRST orbit in less than 85 minutes.

Just to show they could.

http://www.americaspace.com/?p=41805

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Docking AP question (No not about performance)

It's about the "Roll". Today I noticed that if I select Roll to 0 degrees, the ports align 180 degrees around. IE, the handle of one faces the portal (rectangle) on the other - This also shows as 180 degrees on NavyFish's DPAI. In the past this wasn't the behavior, Handle would face Handle, Portal would face Portal, and DPAI would show 0 degrees.

Is this an error, or by design. Just off the top of my head I am thinking, tho I have no time to check, that maybe this avoids 2 shields ports from clipping their "doors" through one another...

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I changed something about that a couple of weeks ago. Did you try with the last dev or the older release ?

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