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

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Up until yesterday MechJeb was working amazingly for me (and most of it still is) but I ran into a problem with timing my auto-piloted ascents to rendezvous. I followed all the instructions in the manual, unless I missed something all four times I read it. First you do the practice launch with the height and heading you want to rendezvous with, end the flight, land or crash, and then do the same thing with the timer on. But during the final ascent MechJeb always pitches my rocket sideways and it crashes into the ground a short way from the KSC, killing the kerbonauts. Does anybody know how to fix this?

This may sound weird, but try defraging your system. It\'s become my SOP anytime MechJeb starts screwing up and usually fixes the problem.

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Uhh, I accidentally pulled a few windows offscreen, is there any way to get them back?

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Uhh, I accidentally pulled a few windows offscreen, is there any way to get them back?

Delete the KSP_win\PluginData\mumechlib\MechJeb.cfg

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I have a problem with MechJeb in 0.15.2. It does all the features well except Munar transfers. When I am in a direct 0° orbit it tries to inject at Munset instead of Munrise like it should.(as if I were in a retrograde 180° orbit), and when I am in a retrograde orbit, it makes the mistake again, injecting at Munrise instead of Munset. I can do the injections by myself, but I like MechJeb\'s precision and being able to get a glass of ale while the transfer is being done for me. I\'ve tried reinstalling MechJeb, deleting the Plugin Data folder for MechJeb, defragging my system like Jontu a few posts above but nothing helps.

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Are you starting from a circular orbit that\'s lower than 100km?

Apparently a change in one of the more recent updates puts everything below 100km in a rotating frame of reference, which the current version of Mechjeb doesn\'t like to deal with.

Once someone told me about it, I started doing my MechJeb-assisted munar transfers from orbits at 125 km altitude, and they went fine.

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Are you starting from a circular orbit that\'s lower than 100km?

Apparently a change in one of the more recent updates puts everything below 100km in a rotating frame of reference, which the current version of Mechjeb doesn\'t like to deal with.

Once someone told me about it, I started doing my MechJeb-assisted munar transfers from orbits at 125 km altitude, and they went fine.

That update was 0.15.1 or .2, it worked in 0.15.0. I \'ll try launching from higher above. That also means I need to relocate my orbital assembly station... redesign Postman I and II supply ships... nah, I\'ll just do it manually.

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Most of the reason i got MechJeb in the first place was for its (usually) EXCELLENT ascent autopilot, and the A.S.S. autopilots. those work just like the default autopilots in Orbiter do, which is exactly what i expected.

Now for the problem i have with MechJeb:

I have been trying and trying to do orbital rendezvous, and somehow i keep messing up. I know the basics from previous experience with Orbiter, how to 'catch up' to the target and match orbits (even if i\'m not on the same plane) but i can\'t seem to figure out when and where to burn so that i don\'t just coast right past the target.

I can usually end up passing by the target within 50-75km or less, but even with MechJeb\'s A.S.S. autopilots helping and the correct target selected for rendezvous AND the info displays provided by the Rendezvous Module, i either end up (still) sailing right past or start to fall behind again.

Then i noticed that the Rendezvous Module actually has autopilots of its own, so i tried those. immediately noticed that the Rendezvous Module autopilots were trying to control the same inputs as the A.S.S. at the same time, so i turned off the A.S.S. autopilots, and let the Rendezvous Module do its thing for a while, watching my orbit in the map view to make sure i did not end up in an impossible orbit. good thing i did, too, because that\'s EXACTLY what almost ended up happening! (good thing i had enough fuel, was able to prevent an unplanned re-entry) and EVERY TIME i engage any of the Rendezvous Module autopilots that take control of the main engine\'s throttle, it seems to end up sending the periapsis of my orbit into the atmosphere, or even right under the surface of Kerbin! the specific autopilots involved are the 'auto-sync', 'home on Y+5m', and 'kill rel. vel' autopilots.

Am I using the wrong autopilots at the wrong time, or is there actually a problem with one or more of the autopilots that i mentioned? a guide on how to use the 'auto-sync' autopilot would be the most helpful to me, as i don\'t actually know what the autopilot is trying to do to synchronize the orbits. i THINK it is trying to match the lat/long coordinates and altitude of the ship\'s Ap and Pe to the target\'s lat/long coordinates and altitude of its Ap and Pe, respectively, but i really dont know how it goes about doing that. going to run some tests with it to see if i can get it to work right.

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From what I have heard, the autopilots tend to fail quite often.

The rest of the rendezvous module should be reliable enough.

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the specific autopilots involved are the 'auto-sync', 'home on Y+5m', and 'kill rel. vel' autopilots.

Auto sync doesn\'t work.

Home and kill rel vel will work only if you are very near the target vessel (say within 10km?). They match your velocity to the vessel exactly. So if you are very far away they will try to make you fly like you are in the part of the orbit that the target vessel is, which will definitely cause problems. (ie if it\'s on other side of planet they will try to make you reverse your orbit to match!)

Kill rel vel I believe will use your main engines. Home I believe will use RCS (so make sure RCS is on).

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What the hell is this, now my KSP won\'t even start. the flickerdoodle...?

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Can you describe the problem a bit more? Just fail doesn\'t say very much.

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I apologize if this has been addressed before.

Recently MechJeb has started acting sort of odd with regards to SAS. While using the ascent autopilot, the SAS gets activated, locking the ship into its current heading, and MechJeb seems unable to disable it. The autopilot will enter the gravity turn stage, but SAS stays locked on and the ship doesn\'t turn. I have to periodically check up on the launch and manually disable SAS or else everything goes pear-shaped. I haven\'t noticed issues with any other functions. This problem started after a few trouble-free days, and I have tried deleting my KSP installation and starting over, so I\'m not sure what the deal is.

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Hi!

I have a problem with the landing system:

When I was about 20 000 m away from mun and orbiting it, I hit the land button. But then my rocket exploded because of 'overheating', but thats impossible because there was no warning before.

Can anyone help me?

Thanks.

PS: If you couldn\'t understand something, sorry -> german speaker :D

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Anyone notice how the module looks like a Space core (SPAAAAAAAAAAAAAAACE!) from Portal 2? ;)

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Sorry to bother you guys about this, but I\'m having a pretty annoying issue with Mechjeb. First of all, I\'m on 15.2, and am not using any other addons or plugins. Here\'s the problem: Mechjeb only works on a clean install of 15.2 (meaning wipe all KSP data, download 15, and patch to 15.2), and even then only works the first time I run the game. For example, I will install KSP, patch it up to 15.2, and drop Mechjeb in the proper folders. I\'ll run the game, and everything will work just as it is supposed to. The next time I try to run the game, however, the Mechjeb pods will disappear from the pod selection window, and everything that uses the MuMechlib.dll will be greyed out in the part selection window. They also throw the 'not available in this version of KSP' error. Any help will be greatly appreciated!!!

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Sorry to bother you guys about this, ......

Which OS do you use? Where did you install KSP? Do the problems occur after a restart of your computer? Is the dll in the plugins directory?

A wild guess: Windows 7; on the c: drive, probably in the root; no; no.

If the first two are true, move KSP to My documents and place the dll once again in the plugins subdir.

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Hi!

I have a problem with the landing system:

When I was about 20 000 m away from mun and orbiting it, I hit the land button. But then my rocket exploded because of 'overheating', but thats impossible because there was no warning before.

Can anyone help me?

Thanks.

PS: If you couldn\'t understand something, sorry -> german speaker :D

On the basis of the description you give it isn\'t really possible to come to a conclusion about the cause, so i have to guess.

(The console (Alt-F2) most probably will provide you with the real reason why this happened). When a rocket engine overheats, a warning indicator is visible, but that doesn\'t happen when an other part is heated. You don\'t get any indication whatsoever. The most likely is therefor that some part is heated by the rocketengine exhaust. If for instance the exhaust hits an RCS tank, that tank will overheat and explode. That explosion often leads to other parts exploding as well (the heat of the explosion causes an overheat of those other parts). Check the console and things probably will become clear to you.

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You probably have issues with te game folder being in Program Files (called \'Programme\' in German if you don\'t know it ;P).

Move it somewhere else or give normal users all rights on KSP folder or run the game as administrator.

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OMG - I\'m not the type to make \'useless\' posts but I used the \'land at KSC\' feature for the first time in a long time. I usually aim for anywhere on Kerbin and end flight when I\'m in a decayed orbit. The end is inevitable so I end flight.

I was absolutely gobsmacked when I used MJ to land at KSC - not a word a lie - MJ landed me on the LAUNCH PAD. Not on the grass beside it. Not into the tower. Not in the drink - on the freaking launch pad. I could not believe the accuracy. Nice maths - well done. :)

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Whats sad is that people think they\'re pro for using mechjeb :/

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Whats sad is that people think they\'re pro for using mechjeb :/

Everybody chooses to play the game the way they want it. If you don\'t want to use it, then don\'t, but such comments don\'t get you far, specially not here.

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I don\'t care about the people who use it.

I care about the people who brag.

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Just saying, nobody brags about using MechJeb...

They inform.

Also, be nice?

(BTW, why does it matter?)

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