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

[togfox]

Agree with above two posts. I use the "Land at" to deorbit and to align the orbit correctly, then disengage and manually land.

[CrashnBurn]

LOL @ togfox....same here. If I know I'm going in with a low TWR, Mechjeb will align the orbit then I can land manually. I think it's easier to land with a low thrust engine on the Mun, stops me from bouncing so much.

[AndrewCoja]

What altitude are you trying to land from? Unless something changed in 1.9.1, I haven't had any problem with landing with mechjeb. If you are too low, MJ might end up overshooting or undershooting the target. When going to Mun, I get into a 50km orbit first and then use the landing autopilot. I haven't had a miss yet. So far I've used the small 3m engine and the thrust vectoring 1m engine. My first two lander were 3m landers with the crew fuel tank and some small 1m tanks strapped to the side. Landed with plenty of fuel. My second lander was one that had already landed, I was just moving it. MechJeb almost planted it right on top of my first lander and I had to use RCS to push it to the side. If you give MJ enough room to land, it will land perfectly.

Also, is there any sort of manual for the rendezvous module? I noticed the MJ manual wiki is outdated and want to know how to properly use the Smart A.S.S. to meet another craft.

[togfox]

Unless something changed in 1.9.1 ...

I think this is the point we're making, something has changed.

[quarthinos]

Would it be possible to give a tooltip or something for the "turn shape" slider in the ascent autopilot? I've been adjusting it with some success, but its difficult to iterate if I have to move the slider by eye. (I suppose I could do it pixel-by-pixel, but YUCK!)

[CrashnBurn]

What altitude are you trying to land from? Unless something changed in 1.9.1, I haven't had any problem with landing with mechjeb. If you are too low, MJ might end up overshooting or undershooting the target. When going to Mun, I get into a 50km orbit first and then use the landing autopilot. I haven't had a miss yet. So far I've used the small 3m engine and the thrust vectoring 1m engine. My first two lander were 3m landers with the crew fuel tank and some small 1m tanks strapped to the side. Landed with plenty of fuel. My second lander was one that had already landed, I was just moving it. MechJeb almost planted it right on top of my first lander and I had to use RCS to push it to the side. If you give MJ enough room to land, it will land perfectly.

Also, is there any sort of manual for the rendezvous module? I noticed the MJ manual wiki is outdated and want to know how to properly use the Smart A.S.S. to meet another craft.

Altitude really makes little difference to accuracy of MJ for Mun landings.

I usually use a 50Km circular orbit, at that altitude MJ misses, by a very wide margin, 100% of the time with a low TWR. I've tried higher and lower altitudes with the same results. I just land manually if I have a low TWR or build with a bit larger engine, then MJ works fine, regardless of orbital altitude.

My feeling is that this has gotten worse in 1.9.1, but I didn't do any testing to verify that.

[Volt]

Yeah, I feel like the latest versions of MJ are having real trouble with precision landings. It totally miscalculates the landing site; I whizz over my selected site, while the deviation still says 0kmN, 0.3kmE, and land two miles away. The landing autopilot has no problem with that.

[Zaran]

So on several of my ships my MechJeb part gets disposed of during re-entry and is no longer a part of the pod that lands, however this seems to make it so I cannot end the flight without ALT+F4ing the game, this also causes all my MechJeb settings to get reset (inputs back to default and all windows back to their default positions.) Any clue how to stop this happening?

[MrMoog]

So on several of my ships my MechJeb part gets disposed of during re-entry and is no longer a part of the pod that lands, however this seems to make it so I cannot end the flight without ALT+F4ing the game, this also causes all my MechJeb settings to get reset (inputs back to default and all windows back to their default positions.) Any clue how to stop this happening?

I've stumble upon the same problem multiple times when trying to perfect a powered escape pod design.

After decoupling an empty pod (with a kerbal in it) equipped with a MechJeb, I will end up having 3 ships available through the [ ] keys, instead of 2. One of those ship is composed of zero part (in game and in the .sfs file) and centered exactly in the decoupled ship. Ending this flight will also end the decoupled ship's flight.

If I don't end the decoupled ship's flight, the MechJeb on one or both ship will begin to behave erratically, usually following one of these behaviors:

- The decoupled ship is not controllable because the MechJeb orientation seems inverted, responding to input the opposite way of what is expected. Every MechJeb features then only make the ship spin furiously.

- The decoupled, or main, MechJeb is no longer functional at all, as in no panel visible, like if it wasn't even present on the ship.

- The game freezes and must be force closed.

This is a major problem since it prohibits one of the most interesting features of this plugin, be it controlling decoupled parts.

[Zaran]

After trying with a fresh install of MechJeb this still happens, but now I cannot even throw open my parachute to land the pod, space bar becomes totally inactive and refuses to trigger anything in the final stage of the craft, going to roll back to 1.9.0 and see if this still happens.

After some testing with MJ 1.9.0 it seems that something in the 1.9.1 update is making staging bug out like it is.

Edited August 15, 2012 by Zaran
Tested Stuff.

[PatientZero]

Hey I'm getting an error on my parts (as well as MMI parts) stating that

"This part is not available in this version of KSP"

Am I doing something wrong?

[speedio]

most probably you have not put the plugin file in the plugin folder of your ksp install. it has the file extension .dll

You need the full version of ksp (not the demo) and put any plugin files in the plugins folder.

[MrMoog]

After trying with a fresh install of MechJeb this still happens, but now I cannot even throw open my parachute to land the pod, space bar becomes totally inactive and refuses to trigger anything in the final stage of the craft, going to roll back to 1.9.0 and see if this still happens.

After some testing with MJ 1.9.0 it seems that something in the 1.9.1 update is making staging bug out like it is.

I just read your edit. That would explain why I only recently been afflicted by this problem. I don't remember having encounter this bug with 1.9, even if I made pretty insane designs.

However, the bug where the controls are inverted (and all automated controls go crazy) was present in 1.9, and even before that if I'm not mistaken.

Will do more tests tonight with 1.9.

[MrMoog]

So I did more testing yesterday with 1.9.1 vs 1.9 and here's the results

Version 1.9.1

I built a stock ship with an escape pod (empty Mk1-2 pod, not stock), and a MechJeb on both the main ship and the escape pod.

After decoupling, a "ghost ship" is created, which is essentially a copy of the decoupled stage, but without any parts. In the persistence, we can see it as a VESSEL entry with the same parameters as the decoupled stage, but without any parts.

This ghost ship cannot be terminated and will cause many problems, like the game finding itself in a deadlock state, the MechJeb interface positions to be reset, and weird physics behaviors.

Another problem is that the decoupled ship (with a MechJeb), have all his WASDQE inputs inverted, resulting in feedbak loops and furious spinning when activating any MechJeb functions (SMART A.S.S., autopilots, etc...).

I can consistently reproduce all those problems.

This version is definitely broken when using more than one MechJeb for controlling decoupled stages/parts.

Version 1.9

After some tests with 1.9.1, I reverted back to version 1.9 and did more tests.

I was unable to reproduce the game-breaking problems encountered in 1.9.1. No "ghost ship" was created, and at no time the game got stuck or the MechJeb interface was reset. We can safely assume that those problems were introduces with 1.9.1.

However, the inverted inputs problem is still there, and probably predate 1.9.

Conclusion

Version 1.9.1 is currently unusable for use in multiple-parts spaceship, and anything requiring more than one MechJeb on one ship.

Version 1.9 is not really better for controlling decoupled parts because of the inverted inputs problem, but at least it doesn't break the game with a ghost ship or impossible to quite states.

So I'll stay with 1.9 for the moment, and I'll go with a request for the plugin dev: is it possible to check into the inverted inputs issue? It's really all that's missing to have a real multiple-parts interplanetary ships!

[PatientZero]

most probably you have not put the plugin file in the plugin folder of your ksp install. it has the file extension .dll

You need the full version of ksp (not the demo) and put any plugin files in the plugins folder.

I've got everything in the right place and I have the full version =/

Maybe it's because I'm using 1.9.1? I'm trying to use Mechanical Mouse Industry parts as well and I'm getting the same error with most of their parts.

The Mechjeb parts are all grayed out and I can't select them.

Can someone provide a 1.9 download link? Thanks!

[Mr. Blue Sky]

I love the Space Core look!

[fiber0pti]

How do you install this? I've put the file in plugins and parts, respectively but I'm not seeing any menu option like on all of the tutorials.

[r4m0n]

Version 1.9.1 is currently unusable for use in multiple-parts spaceship, and anything requiring more than one MechJeb on one ship.

Version 1.9 is not really better for controlling decoupled parts because of the inverted inputs problem, but at least it doesn't break the game with a ghost ship or impossible to quite states.

So I'll stay with 1.9 for the moment, and I'll go with a request for the plugin dev: is it possible to check into the inverted inputs issue? It's really all that's missing to have a real multiple-parts interplanetary ships!

Fixed the problem here, I was messing with the handling of decouplers in the ejected stages and something broke. I'll get a 1.9.2 out soon with it and a few extras.

[Koschei]

Please put in CrashnBurn's suggestions in post #323, it would make MechJeb that much more complete.

[MrMoog]

Fixed the problem here, I was messing with the handling of decouplers in the ejected stages and something broke. I'll get a 1.9.2 out soon with it and a few extras.

Great news, thanks!

So the "ghost part" was the decoupler! That's what I guessed, seeing that sometimes the decoupler model would stay attached.

Have you found anything on the inverted inputs problem? Is it something you have been able to reproduce?

This plugin is incredibly nice for complex missions, and having this issue resolved could mean thing like big interplanetary ships with multiple drop pods or rovers to drop on the many new planets and moons. Or multi-parts spaceships, that include an orbiter, an habitat, a rover and a return ship, all in one.

[Ekku Zakku]

I'm with MrMoog, as we've been discussing MechJeb on the Crew-able empty pods mod thread. The decoupler issue was the perfect fix for me, and allows me to functionally use the ship I created perfectly, but the inverted controls and the insane spinning out of control makes it unflyable. The problem DOES exist even with just one MechJeb module on a ship, as my Mun lander can attest to. It was attached to the separated parts however, so that might have been the issue? Idk.

Also it's strange that the controls are sometimes inverted, but sometimes not. I sent my tiny command pod along with a large pod into orbit and the separated pod controlled correctly, yet my much larger lander with many more pieces did have inverted controls. Idk if it was the extra parts, or that I was in the Mun's orbit that caused it though (I'm assuming it's the extra parts).

Edited August 17, 2012 by Ekku Zakku

[r4m0n]

I'm with MrMoog, as we've been discussing MechJeb on the Crew-able empty pods mod thread. The decoupler issue was the perfect fix for me, and allows me to functionally use the ship I created perfectly, but the inverted controls and the insane spinning out of control makes it unflyable. The problem DOES exist even with just one MechJeb module on a ship, as my Mun lander can attest to. It was attached to the separated parts however, so that might have been the issue? Idk.

Also it's strange that the controls are sometimes inverted, but sometimes not. I sent my tiny command pod along with a large pod into orbit and the separated pod controlled correctly, yet my much larger lander with many more pieces did have inverted controls. Idk if it was the extra parts, or that I was in the Mun's orbit that caused it though (I'm assuming it's the extra parts).

Just a guess for now, but I think the RCS thrusters are remembering the previous vessel configuration, and the changed center of mass makes everything work in reverse sometimes. I'll take a look at this, and if that is the case, see if I can tell them to re-analyze the vessel.

[PatientZero]

I'm getting an error here

"This part type isn't available in this version of KSP".

I have 0.16 and the plugins dl'd... Not sure what I'm doing wrong. I have them in the plugin folder.

[JDP]

Just a guess for now, but I think the RCS thrusters are remembering the previous vessel configuration, and the changed center of mass makes everything work in reverse sometimes. I'll take a look at this, and if that is the case, see if I can tell them to re-analyze the vessel.

If you could find a fix for this it would be pure awesome! I found the same issue in SAS on Debris. After forcing SAS to apply torque, it would act as if the center of gravity was still where it was before decouple. The SAS PID would run on killRot, but the error correction values would be way off.

[cyclestart]

Is it possible to use mechjeb to keep ones ship pointed at a another ship similar to how you can use smart ass to stay pointed pro/retro grade, normal ...ect?