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

[Innuce]

Sorry if this has been brought up already, but I'm having trouble with losing control of my craft once I use the MechJeb Autodocking.

After my craft docks to another, I no longer have control of the docked-together crafts unless I go back to the space center and re-select the craft to fly.

Is this normal? Is there a workaround I'm not aware of?

[Simplicity]

You can try this method for docking.

http://forum.kerbalspaceprogram.com/showthread.php/29518-Tutorial-Easy-mode-docking-with-MechJeb-2-0

It's a great tutorial you did for docking, although it's a pity that it will not work if you are docking to really LARGE stations or are using really large ships to dock with which do not turn easily

Alas what I am finding not only in mechjeb) is that a lot of mods etc do not take into account people using BIG ships or stations in the game, expecting a 200 ton vessel to turn and line up for things etc in the same time frame as it would take a 10 ton ship doesn't seem to be in the equation

[The_Duck]

A couple people posted about having problems with the blacklist feature. I've just fixed a bad bug with that, and if you want you can download a fixed dev build at http://jenkins.mumech.com/job/MechJeb2/ . Just grab MechJeb2.dll from that page and use it to replace your current version at GameData/MechJeb2/Plugins/MechJeb2.dll. [This build also fixes some other problems, such as rendezvous AP failures and SRB dV not being account for correctly.]

I've also updated the MechJeb wiki page about blacklisting for accuracy: http://wiki.mechjeb.com/index.php?title=Manual/Blacklisting_modules#How_to_blacklist_various_modules

There might still be some lurking problems related to blacklisting, but it shouldn't be completely unusable anymore.

Hello, can anyone confirm this or explain why when using MechJeb the frame rate seems to be capped at 30 whilst without it well... sky's the limit. I just find it a bit odd is all and I was wondering if it was by design. The previous 2.07 caused weird sound bugs and a constant 2 second lag spike.

Ideally MechJeb would have no effect on framerate. For large ships, though, it does a lot of calculations, which might slow things down on large enough ships. Do you experience lower framerates specifically when you have certain MechJeb windows open, or just whenever it is on the ship, even if all windows are closed? Also, how are you measuring framerate?

Before I start asking specific questions, is there a known issues list at all ?

We have an issue tracker on Github at https://github.com/MuMech/MechJeb2/issues . Creating an issue there is the best way to report a bug.

Bit of an annoyance, everytime i set mechjeb the task of landing on the mun it gets to approx 1-2metres and decides it wants to flip upside down.

I tried to land on target on the Mun and evrything is fine until the surface velocity reaches 0m/s (final descent stage).

Just after that it looks that mechjeb wants to keep following the retrograde mark on the navball and the result is that the ship starts spinning and everything finish in a big bang on the ground...

I'd like to fix this problem but I need a good test case. Can one of you or someone else with the same problem post a .craft file of your lander?

My surprise came when I started the game, went to one of my in progress flights, and there was no MechJeb tab on the right side of the screen!! I tried to launch a new vessel, too, but it didn't appear there neither. Am I doing sth wrong??

You have to add a MechJeb part to a vessel before you can use it. The MechJeb part can be found in the editor same tab as the stock SAS parts.

Sorry if this has been brought up already, but I'm having trouble with losing control of my craft once I use the MechJeb Autodocking.

After my craft docks to another, I no longer have control of the docked-together crafts unless I go back to the space center and re-select the craft to fly.

Is this normal? Is there a workaround I'm not aware of?

It doesn't sound normal, but what does "losing control" mean? Your commands do nothing, and don't even move the control input indicators in the lower left? The indicators move but your craft doesn't? The craft starts spirally crazily?

Is the "stage lock" indicator purple? Is the craft unmanned and out of electricity? Are there red error messages filling up the debug log (Alt-F12 to bring it up).

Edited May 31, 2013 by The_Duck

[SoraHjort]

You have to add a MechJeb part to a vessel before you can use it. The MechJeb part can be found in the editor same tab as the stock SAS parts.

http://imageshack.us/a/img42/2862/mechjeb21.png - Showing I have it in the right directory

http://imageshack.us/a/img829/2208/mechjeb22.png - Showing that even though I have the part attached, it does not show the MechJeb tab anywhere.

This appears to be a problem that a lot of people have been complaining about in the last bunch of pages since .20 got released. I'm wondering if this is affecting just Steam users.

KSP version: 0.20.2

MechJeb2 version: 2.0.8.0-58 (latest dev as of posting)

Edited May 31, 2013 by SoraHjort

[HoY]

It's a great tutorial you did for docking, although it's a pity that it will not work if you are docking to really LARGE stations or are using really large ships to dock with which do not turn easily

Alas what I am finding not only in mechjeb) is that a lot of mods etc do not take into account people using BIG ships or stations in the game, expecting a 200 ton vessel to turn and line up for things etc in the same time frame as it would take a 10 ton ship doesn't seem to be in the equation

I Actually use this, as I said probably 3 times both in this thread and in the comments on the video itself for docking my 100-400 tonne ships. If you find its not working for you, its not because it doesnt work!! if your trying to turn your 300t ship with a probe core and no RCS, yes, its not going to work. but with a single 3man capsule it works just fine, and even better with RCS. I would have already had a new video demonstrating that uploaded, but ive spent my last couple weeks livestreaming instead of youtubing.

If you try it and dont like it, thats one thing, but it does work!

[Innuce]

It doesn't sound normal, but what does "losing control" mean? Your commands do nothing, and don't even move the control input indicators in the lower left? The indicators move but your craft doesn't? The craft starts spirally crazily?

Is the "stage lock" indicator purple? Is the craft unmanned and out of electricity? Are there red error messages filling up the debug log (Alt-F12 to bring it up).

Ok, what I mean by losing control is I no longer can use pitch or roll. The ASAS does nothing, yet I can turn it on and off. I can activate RCS, that works. Smart A.S.S. doesn't work either. It won't react to execution of nodes either.

The light under "Stage" is green. The indicators in the lower left do move when I try to pitch or roll. The craft isn't spinning crazily, it just sort of drifts. Oh, and all the action keys work, I can turn lights on and off, ladder, etc.

The Craft is manned and powered (both nuclear and solar). Plenty of RCS fuel and Liquid fuel. Each craft has it's own MechJeb2 on it. Never had trouble before with them getting confused or anything.

The only message I get in the debug is "[Log]: Skipped rendering frame because GfxDevice is in invalid state (device lost)". Nothing in Red.

I have repeated this maneuver a half dozen times now, same result. But if I escape back to space center and reselect the craft, everything is fine. Seems like the ASAS is on, even though I can turn the light on and off and everything in MechJeb2 is turned off.

Here's an image of the docked crafts...

Edited May 31, 2013 by Innuce

[Innuce]

Ok, there's more...

If I undock the crafts, the one with the lander cannot be controlled, but the big orange tank can. Also, I noticed on the craft with the lander, all the stages are lumped together into stage 0 after undocking.

Other than this issue, I really like the docking feature in Mechjeb2. Very easy to use, and works like a charm! Even for docking things side by side like this with the double ports. Uses alot of RCS though...

I'm having a separate issue where the docking ports rip apart after warping time. Maybe because I'm using the small octagonal struts to mount the docking ports?

Edited May 31, 2013 by Innuce

[buzuc]

I'd like to fix this problem but I need a good test case. Can one of you or someone else with the same problem post a .craft file of your lander?

There you are:

http://www./?uhip6hd6u2tmg2b

I only uploaded the lander part.

[Simplicity]

If you try it and dont like it, thats one thing, but it does work!

Please don't get me wrong, I do like it, it just doesn't seem to work too good for me - my station has a very hard job in turning..

I have tried your method on smaller ships and it does work brilliantly, maybe I should have worded my message a little differently by saying it does not seem to be working FOR ME, for that I appoligise

[KhaosCorp]

Other than this issue, I really like the docking feature in Mechjeb2. Very easy to use, and works like a charm! Even for docking things side by side like this with the double ports. Uses alot of RCS though...

try using small bursts of RCS, also something I been playing with is mounting sas rings close to main rcs placement...helps a wee bit on huge ships....

or you could look into installing HydroTech as well, that mods lets ya do a lot, but the best part (for this at least) is you can set how much gas your rcs nozzles actually use. My main Kerbin SoI space station is a total of 214ish tons (depends on how much fuel its got lol) I can flip it from facing prograde to retrograde in about 30 seconds, and only use about 6 units of monoprop, I have over 40 rcs jets, but all set to use 0.05 units a second

[jeti140973]

Great addon. Just installed the 2.0.8 version, and having fun. Really impressive features. However, I want to suggest adding two types of maneuvers in the future, if it is possible. These may already be possible with some skilled use of the existing maneuvers, but I sure can't figure it out. These maneuvers may have a real-life term that I am not familiar with.

1) ballistic flight, ie. flying from one location on a planet to another (specified) location on the same planet without first establishing an orbit - via a ballistic trajectory. Basically, an ascent turning into a landing at the apoapsis. This would be useful in a number of situations, for example when launching probes to the anomalies on Kerbin, or if travelling between bases on the same planet/moon.

2) direct descent, ie. when entering the SOI of a planet you land directly at a (specified) location without first establishing an orbit. Not sure if this is cheaper or more expensive in delta-v, but it could be useful for low-grav moons and for impact probes, if you want to hit a specific spot.

[Castun]

I have repeated this maneuver a half dozen times now, same result. But if I escape back to space center and reselect the craft, everything is fine. Seems like the ASAS is on, even though I can turn the light on and off and everything in MechJeb2 is turned off.

Here's an image of the docked crafts...

I've had the exact same problem where I lose control and can't do anything until I switch craft and back, but I don't think that's MechJeb. Do you happen to be using the RemoteTech mod too?

Also, I think the stages being thrown together after undocking a craft is due to the way the game handles spent sections. If you start out with a command capsule and then build a rover on top of it, once you detach it, it thinks that the rover is a spent stage and ignores the staging order once you eject it.

[Arran]

I have the problem when orbitting the Mun, and try too rendezvous my ships for docking, mechjeb suddenly starts too lag, the manouvre takes 68y,35d my RCS is going nuts (randomly shooting in all directions) and my FPS drops below 10..

As soon i turn autopilot off, the game gets back too normal..

This is with Mechjeb 2.0.8 ..

The Log Window also gets at this point flooded with error messages..

Here you see the manouvre takes about 68years too complete

Here you see how my Log is flooded with Rendezvous Autopilot

https://www.dropbox.com/s/03ricovt6eybnqo/LogError.png

I dont have this problem around Kerbin, it just seems too happen around the mun (havent tried any other bodies yet)

Tried too reset Mechjeb, wiped the PluginData of Mechjeb, tried a reinstall of Mechjeb

Edited May 31, 2013 by Arran

[Oddbin]

So, anybody having problems with docking, I honestly recommend using ORDA when docking.

Mcjeb is useful for the rendezvous, but the docking part is done by ORDA, which can flip out when done by mcjeb.

AFAIK ORDA isn't being developed anymore. Has someone else picked up the project?

[Xonxez]

Nope, I guess that's it xDD

[sarbian]

@Arran try the dev build, something like that was fixed ( https://github.com/MuMech/MechJeb2/issues/103 )

[Innuce]

try using small bursts of RCS, also something I been playing with is mounting sas rings close to main rcs placement...helps a wee bit on huge ships....

or you could look into installing HydroTech as well, that mods lets ya do a lot, but the best part (for this at least) is you can set how much gas your rcs nozzles actually use. My main Kerbin SoI space station is a total of 214ish tons (depends on how much fuel its got lol) I can flip it from facing prograde to retrograde in about 30 seconds, and only use about 6 units of monoprop, I have over 40 rcs jets, but all set to use 0.05 units a second

Once I engage the docking autopilot, I have no control anymore of the RCS. The best I can do is get the craft close as possible before engaging the autopilot. But if you can get it that close, you don't really need autopilot anymore right?

I think an improvement would be for MechJeb2 to incorporate using Rockets and SAS whenever possible to minimize the use of RCS fuel. I have to admit, the MechJeb autodocking works really well though!

[entaran]

Mechjebs autodockign works a lot better if you attack your time accelerate keys with a vengeance to avoid the huge RCS burns. Docking camera mod helps a crazy amoutn here too.

iv'e got MJ Autodock working now more efficiently than I can do it manually simply by hitting > and < a lot to speed up and slow down time (so it doens't make constant adjustments)

[Innuce]

I've had the exact same problem where I lose control and can't do anything until I switch craft and back, but I don't think that's MechJeb. Do you happen to be using the RemoteTech mod too?

Also, I think the stages being thrown together after undocking a craft is due to the way the game handles spent sections. If you start out with a command capsule and then build a rover on top of it, once you detach it, it thinks that the rover is a spent stage and ignores the staging order once you eject it.

The only mod I have active is MechJeb2. I do not have RemoteTech at all.

I agree, this may not even be a MechJeb2 problem. I should try to re-create this problem by docking these crafts without using MechJeb2, but docking 2 large crafts manually with dual docking ports is very difficult for me.

My rover was never detached before this happened. I was actually mating up with the Refueling station (the sole orange tank), then I was going to detach the lander/rover, leaving the two big orange Refuelers attached to each other in orbit. I guess you could say it's 3 crafts altogether.

[Innuce]

I wonder if setting the "Speed Limit" lower on MechJeb2 Autodocking would help reduce RCS usage?

Faster usually means less efficient in these things. Perhaps if I set it to some ridiculously low value like 0.1 m/s?

[Fyrem]

while I haven't exaustivly tested the "speed limit" yet, the few tests I did, did not seem to effect anything at all.

[Innuce]

while I haven't exaustivly tested the "speed limit" yet, the few tests I did, did not seem to effect anything at all.

Me too. I actually had it set to 3 m/s hoping it would be faster, but it never reached that speed. However, I have not tried the opposite extreme yet...

[robertordf]

I have found a bug with solid boosters.

The dV calculated is wrong, they don't match with my spreadsheet. Looks like that the dry ratio mass isn't considered. When I put dry ratio mass to infinite, matches with mechjeb.

Have someone already addressed that?

[HoY]

I have found a bug with solid boosters.

The dV calculated is wrong, they don't match with my spreadsheet. Looks like that the dry ratio mass isn't considered. When I put dry ratio mass to infinite, matches with mechjeb.

Have someone already addressed that?

Read a few posts back, this was fixed with the new dev build

[FredMSloniker]

For folks having trouble with MechJeb's inefficient use of RCS, there are two things you might try. One is the RCS balancer. It doesn't work with every rocket design--I had a weird issue with one rocket with unusual RCS jet placement until I turned it off--but if you've got the standard one or two banks of four, it should cut down on fuel usage.

The other is that, although it's not visible by default, there's a lot of docking information that MechJeb can provide. Open the custom window editor and go to the 'Target' section (just under 'Click an item to add it to the window'). You can make a new window and add the docking info to it. That should help you guide the ship in manually.