r4m0n

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

Recommended Posts

Ran into a wierd errorspam right as I landed at Mohos sinkhole ridge (well, the northern, less rugged, part) and at the same time, the surface info window started flickering rapidly. The spam stopped when I closed the surface info window, going to KSC and back didn't fix it either.

I restarted anyway because there is some sort of memory leak (I suspect KSP, not any mod) and wanted to clear that. Restarting didn't help the errorspam I saw. Build 466.

Managed to catch a screenshot between flickers.

screenshot26_zpstuipivet.png

Output log: http://sta.sh/01fpcu8nhj8c

Edit: Landing near the mohole does this too. Not to mention a massive memory leak somehow, not from MJ obviously.

Edited by smjjames

Share this post


Link to post
Share on other sites

loppnessmonsta : yes. And I totally forgot to update it. I ll try to think about it tonight.

smjjames : thanks for the log

others : I already explained the source of the problem yesterday and yet the thread has an other 20 posts about the same subject and baseless speculation. If it I get one more day like that I ll ask to close the thread until I can fix the bug properly.

Share this post


Link to post
Share on other sites

I've been wondering is precise landing like 'land on the KSC launch pad' is out of the question now? I tried Landing assistance with several different crafts (light, medium, heavy, aerodynamic or not, powered landing and with parachutes) but MJ missed the KSC every single time. (~30 km is the best result).

Share this post


Link to post
Share on other sites
Oh, i wasn't aware of that.

thanks

LGG

I noticed that the field which says where to stop staging doesn't get saved. For example, if I tell it to stop staging at stage 7, leave the scene and then come back, it is back to zero again

Share this post


Link to post
Share on other sites
Try 466? It's the most current dev build.

I am now using build 460 and all seems right again.

Now that it is working, I'm too scared to try 466... :)

Share this post


Link to post
Share on other sites

@ sabian Sorry didn't mean to poke the hornet's nest. I have alot of experience in the "thought it was a bug, turns out it was me" thing. :) Sometimes I just need to shut my keyboardhole.

Share this post


Link to post
Share on other sites
Terminal Velocity throttle limiter is working very nicely now. Good and smooth!

The TV limiter seems to be still broken for me. It works up until a certain point limiting to just shy of 300m/s at around 3k altitude-- this seems a lot faster than previous versions, I am starting to see mach effects) it gradually goes back up as the air thins (as it should) reaching full throttle around 11.5k altitude. I drop the first stage and start my gravity turn, but at around 15km it totally kills the engines for no apparent reason throwing the craft out of control.

Perhaps some sort of gap in the way the TV is calculated in that altitude window?

Share this post


Link to post
Share on other sites

I've been having a string of launches (well, launch and revert to try and fix) where MJ is forgetting to fully lower timewarp before actually launching. I took this screenshot immediately before manually lowering timewarp to where it should be.

screenshot28_zpsprplgf6f.png

Output log: http://sta.sh/024ccm11vf5f

Also, while not related to the screenshot, when I looked at the output log, I noticed that it threw lots of exceptions in drive from the rendevous AP. Not sure exactly when it happened because it doesn't show in exceptiondetector, but I have noticed that it has difficulty with fine tuning rendezvous for asteroids and seems to try to go for the exact center.

Edit: Found the cause or rather the situation that was generating that exception in drive, it was getting stuck on matching planes with an asteroid.

Edited by smjjames

Share this post


Link to post
Share on other sites
... reaching full throttle around 11.5k altitude. I drop the first stage and start my gravity turn, but at around 15km it totally kills the engines for no apparent reason throwing the craft out of control.

It is likely that the issue is with the "lift" generated by the atmosphere between 15 km and 30 km overpowering your guidance system. With atmospheric effects being much more prominent in KSP 1.0, you have to be very careful to maintain a reasonable acceleration and speed until you are above 35 km. These issues are not related directly to MechJeb but to the design of your spacecraft and the ascent path that you have setup.

skips

Share this post


Link to post
Share on other sites

I noticed the game mechanics are funky when calculating terminal velocity on rockets. I added it to the MJ Vessel info and it keeps jumpin from values like 600m/s to 200m/s. This might be useful info.

Cheers,

Share this post


Link to post
Share on other sites
I've been having a string of launches (well, launch and revert to try and fix) where MJ is forgetting to fully lower timewarp before actually launching. I took this screenshot immediately before manually lowering timewarp to where it should be.

http://img.photobucket.com/albums/v214/smjjames/screenshot28_zpsprplgf6f.png

Output log: http://sta.sh/024ccm11vf5f

Also, while not related to the screenshot, when I looked at the output log, I noticed that it threw lots of exceptions in drive from the rendevous AP. Not sure exactly when it happened because it doesn't show in exceptiondetector, but I have noticed that it has difficulty with fine tuning rendezvous for asteroids and seems to try to go for the exact center.

Edit: Found the cause or rather the situation that was generating that exception in drive, it was getting stuck on matching planes with an asteroid.

What mod are you using in this picture to give you the orbit information next to the warp indicator in the upper left?

- - - Updated - - -

It is likely that the issue is with the "lift" generated by the atmosphere between 15 km and 30 km overpowering your guidance system. With atmospheric effects being much more prominent in KSP 1.0, you have to be very careful to maintain a reasonable acceleration and speed until you are above 35 km. These issues are not related directly to MechJeb but to the design of your spacecraft and the ascent path that you have setup.

skips

That would explain the lack of control when the engine is cut, but does not explain why MJ is cutting my engines down to zero in the first place.

Share this post


Link to post
Share on other sites
What mod are you using in this picture to give you the orbit information next to the warp indicator in the upper left?

That's Kerbal Engineer Redux.

Share this post


Link to post
Share on other sites

Hi everyone !

I'm having some trouble setting up a good ascent profile for MechJeb + FAR. Basically, my rocket always ends up going too fast in the lower atmosphere and is destroyed by the Mach effects.

What I do when I'm flying manually is :

- Reach 100 m/s at about 1 km or slightly less

- Start a slow gravity turn by pointing the rocket 5-10° East

- Aim for 300 m/s at 10 km

- Eyeball the rest of the gravity turn by checking the evolution of the Mach effects around the rocket

With MechJeb ascent guidance, it becomes : watch the rocket disintegrate at 5 km as it goes over the speed of sound.

The only way to prevent this would be to use the "Limit to terminal velocity" function, but it never worked with FAR. Is there an alternative to keep the rocket from overspeeding while in the dense layers of the atmosphere ?

Share this post


Link to post
Share on other sites

@ jashin, as for FAR, there's a dll patch that MJ needs in order to work properly with it and Sarbian said yesterday that he'll check it out.

As for the disintegration, you may have aerodynamic structural failures (a FAR feature) on, use the FAR button in the KSC screen to turn that off. Although if you want that on, use limit acceleration to 18 m/s until around 20-25km.

Share this post


Link to post
Share on other sites

That would explain the lack of control when the engine is cut, but does not explain why MJ is cutting my engines down to zero in the first place.

Turn off the AOA limiter and adjust your ascent path to match the turn profile you need to keep from losing control.

skips

Share this post


Link to post
Share on other sites

I'm having some trouble with mechjeb not adding in the angle to launch to rendezvous box. Normally it adds in the angle, but out of nowhere it refuses to work. I can add in my own angle, but without being too accurate, it's worthless, and I made my rockets to barely scrape by with the necessary Dv to do their jobs, because I feel that extra fuel is a waste of money. Any help would be great, cuz for all I know mechjeb has become sentient and has begun phase one of the invasion of kerbin!

Share this post


Link to post
Share on other sites

Hi All,

Does anyone have a solution. Slapping mechjeb on anything gives lag/fps drop every second. This problem seems to get worse the more ships there are out there using mechjeb. One ship with mechjeb is not a problem, but after launching multiple ships the problem gets worse. Removing or launching anything without mechjeb makes the game behave just fine. I suspect that mechjeb tries to calculate the delta_v for every ship at every physics tick, making the game unplayable. Now I do rely on mechjeb, I'm better at building than at flying. Does anyone have any idea how to fix it?

The game is ran at 64 bits ubuntu.

Greetings,

Jelmer

p.s I understand more information might be needed to debug this. I can provide anything if needed.

This happens on my PC aswell as my laptop.

p.s 2. This is purely a mechjeb issue, slapping a ker unit onto my ship does not give the lag every 0.8? sec?

Edited by jelmew

Share this post


Link to post
Share on other sites
I noticed that the field which says where to stop staging doesn't get saved. For example, if I tell it to stop staging at stage 7, leave the scene and then come back, it is back to zero again

Bump!

Share this post


Link to post
Share on other sites
I noticed that the field which says where to stop staging doesn't get saved. For example, if I tell it to stop staging at stage 7, leave the scene and then come back, it is back to zero again

Does it happen to you if you launch a craft, set the staging in ascent AP (well, I set it to stage one because the craft I used only has the main stage, decoupler, and launch stage), return to KSC, and come back to the ship? Because I did that and it saved.

Also, is the landing at target AP acting a bit funny on Ike for anybody else? It keeps warping between the killing horizontial velocity and the final landing burn. I keep thinking MJ is going to smash the lander into the ground. Starting at a low orbit of ~20km may have something to do with it.

Share this post


Link to post
Share on other sites

Arghh. Frustrated. Using the 466 build. Still no luck getting MJ to activate or control the throttle at node execution. New windows 7 install with new KSP install and all the latest versions of the mods. Any ideas?

Log

Mods

Share this post


Link to post
Share on other sites
Arghh. Frustrated. Using the 466 build. Still no luck getting MJ to activate or control the throttle at node execution. New windows 7 install with new KSP install and all the latest versions of the mods. Any ideas?

Log

Mods

try removing some mods, see if that helps.

just an Idea.

Share this post


Link to post
Share on other sites

You probably already checked this, but I've gotten frustrated enough times over this: did you have enough electricity to activate your engines? (If you had RT2 I'd ask if it was a probe and was there a connection to KSC) Obvious stuff, but sometimes after banging your head a bit you miss things like that. I hope you find a fix. I hope mine was it. Simple.

Share this post


Link to post
Share on other sites

might have been answered already and i havent seen it..but i DLed the newest version of MJ and my ascent guidance window is gone. no options for it no nothing. is it farther along on the tech tree now? im not seeing it listed if it is. anyone have any ideas how to remedy this?

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.