[1.12.x] Anatid Robotics / MuMech - MechJeb - Autopilot - [2.14.3] [4th March 2023]

[Capt. Hunt]

On 4/28/2018 at 5:07 PM, Someone2018 said:

Is it possible to get landing guidance that is accurate within a meter on Kerbin? I was trying SpaceX style ship landing, and it missed the boat by ~50 meters. I do realize in most cases wasting fuel on moving 50 meters is totally silly and can cause crashes due to running out of fuel, but still I'm curious.

the landing guidance is not really optimized for atmospheric flight.

[Platonicsolid]

I've looked back through posts and haven't seen an answer to this, apologies if I missed it

Is it possible to use the current MechJeb2 release on 1.3.1? I'm still on 1.3.1 because GPP hasn't updated for 1.4.x yet and I don't want to toss my career. That said, I'm also seeing dV calculation issues that may be fixed on the current MJ.

Thanks!

[sarbian]

30 minutes ago, Platonicsolid said:

I've looked back through posts and haven't seen an answer to this, apologies if I missed it

Is it possible to use the current MechJeb2 release on 1.3.1? I'm still on 1.3.1 because GPP hasn't updated for 1.4.x yet and I don't want to toss my career. That said, I'm also seeing dV calculation issues that may be fixed on the current MJ.

Thanks!

No, they are not really compatible. But the dev version #786 should have the dv fixes and was the last one for 1.3.x 

[Platonicsolid]

Awesome, I'll grab that and give it a shot. Thanks much!

[Jimbodiah]

Is it somehow possible to add supportfor SSTU solar panels, as it does not use the stock module? Can this be patched through MM or is it handled in the plugin itself?

[oversoul]

On 5/3/2018 at 10:57 AM, sarbian said:

No, they are not really compatible. But the dev version #786 should have the dv fixes and was the last one for 1.3.x 

Exactly what I came here for. Thanks again, sarbian!

[PicardSpeedo]

Hey gang - 

Chiming in here as well - since the update to KSP 1.4.3, not only am I seeing the weird '90 degree twist' when docking, as described by others, but also, none of my ships, which used to get to orbit super-efficiently pre-1.4.3, can now do so. Using Ascent Guidance's autopilot now results in rockets making it to about 44 to 48 kilometers up, and then willfully steering back down into the atmosphere. The entire time, MechJeb sits on 'Gravity Turn,' regardless of the ascent profile selected, and never advances. For craft that actually do get to an orbit, desired altitude is never respected by the program. 

This happens constantly and repeatably. Can anyone help?

[icecold951]

Unpleasant issue that MAY be caused by MechJeb. During it's use, sim rates can steadily crash to very poor. It might be another mod, but only happens when using MechJeb. Acts like a memory leak.

[PicardSpeedo]

Just did more testing. Absolutely something wrong with MechJeb after 1.4.3 update. Even after manually intervening with the ascent profile, ultimately, I get the same results as described above. Annoyingly, even manually going to orbit and then kicking MechJeb on to finalize the orbit altitude results in the the ship descending back into the atmosphere. 

Possibly related: getting out of the atmosphere feels like it takes longer now.

Edited May 11, 2018 by PicardSpeedo

[Jim DiGriz]

On 5/10/2018 at 7:37 PM, PicardSpeedo said:

Just did more testing. Absolutely something wrong with MechJeb after 1.4.3 update. Even after manually intervening with the ascent profile, ultimately, I get the same results as described above. Annoyingly, even manually going to orbit and then kicking MechJeb on to finalize the orbit altitude results in the the ship descending back into the atmosphere. 

Possibly related: getting out of the atmosphere feels like it takes longer now.

There's a lot of different Ascent Guidance options.  You're going to have to be much more specific about what you're trying to do, how you're trying to do it, and what is going wrong.

AFAIK nothing got touched recently, I've been off working a major overhaul that turned into another major overhaul...

[Jim DiGriz]

On 4/28/2018 at 5:07 PM, Someone2018 said:

Is it possible to get landing guidance that is accurate within a meter on Kerbin? I was trying SpaceX style ship landing, and it missed the boat by ~50 meters. I do realize in most cases wasting fuel on moving 50 meters is totally silly and can cause crashes due to running out of fuel, but still I'm curious.

I believe the existing code in MJ was written to handle the pre-1.0 soup atmosphere, and will not work post-1.0

I don't know of anyone trying to tweak the existing algorithm to make it work.

I'm working on writing an actual grown-up trajectory optimization algorithm for MechJeb to use (not a highly limited finite burn executor like PEG) which should be able to solve nearly any problem.  With the addition of aerodynamic forces it should be able to solve the hoverslam problem exactly (without any deep throttling).  But I'm months away from that.  I don't have a lot of interest in trying to kerbal up fixes to the existing code.

The best way right now to do SpaceX style launches may be writing your own kOS code or modifying someone else's and not using MechJeb.

[El Sancho]

On 5/10/2018 at 11:37 PM, PicardSpeedo said:

Just did more testing. Absolutely something wrong with MechJeb after 1.4.3 update. Even after manually intervening with the ascent profile, ultimately, I get the same results as described above. Annoyingly, even manually going to orbit and then kicking MechJeb on to finalize the orbit altitude results in the the ship descending back into the atmosphere. 

Possibly related: getting out of the atmosphere feels like it takes longer now.

Pretty much what Jim said. There's a ton of settings. Why don't you show us a screenshot of your rocket on the pad, with a good clear look at your Ascent Guidance settings, preferably with the ascent profile screen open so we can see what's going on. It's entirely possible that this will enable the community to offer you some positive suggestions.

[rsparkyc]

I'm seeing similar issues with the PEG guidance not always working.  One specific thing I noticed is that PEG fails to work if I have a mammoth as my first stage.  It will throw exceptions in the logs, which I've documented here: https://github.com/MuMech/MechJeb2/issues/1029 EDIT: It looks like I actually just had my number of stages in the ascent guidance config set too high.

In addition, I've also noticed that some craft will fail to achieve orbit using PEG guidance mode, and when doing so, also spams the logs with exceptions, as documented here: https://github.com/MuMech/MechJeb2/issues/1026

I'm assuming these issues are what you all are seeing as well, so hopefully having open issues will help get this some traction.

Edited May 16, 2018 by rsparkyc

[Shalfar]

On 5/10/2018 at 9:37 PM, PicardSpeedo said:

Just did more testing. Absolutely something wrong with MechJeb after 1.4.3 update. Even after manually intervening with the ascent profile, ultimately, I get the same results as described above. Annoyingly, even manually going to orbit and then kicking MechJeb on to finalize the orbit altitude results in the the ship descending back into the atmosphere. 

Possibly related: getting out of the atmosphere feels like it takes longer now.

I'm running the latest dev build and not seeing this issue.  What build are you using?

[Xd the great]

I seem to find a problem that mechjeb does not know how to use brakes to slow rovers, so they charge downhill. And brake.

Typical jebediah actions.

Mechjeb 2 and v 1.4.3

Edited May 21, 2018 by Xd the great
How to include the log

[Virtualgenius]

Does anyone else get re-entry simulation timed out when using the landing guidance dev 800 version

Edited May 27, 2018 by Virtualgenius

[Capt. James T. Kirman]

Hi. Is it possible to make a custom coordinate preset for landing guidance, such as the KSC pad and VAB ones? And if so, how do I do so?

[El Sancho]

create file LandingSites.cfg with notepad

save it in ...\Kerbal Space Program\GameData\MechJeb2

paste in the code between the two lines of asterisks below, but without those two lines of asterisks themselves, then add your own entries in the same format, paying very careful attention to those squiggly parentheses. Note that while the two landing sites I have added both  do work, (though you will still land well west of the destination, because the landing module isn't designed for in-atmosphere use), the two entries I have added for the Desert Runways do NOT work, and I have no clue why.

How do you get the data to enter? Well, in Mechjeb therte's a thing called Custom Window Editor, and under MISC it has an entry to add a button which copies your latitude, longitude, and altitude to clipboard.

************************

MechJeb2Landing
{
    LandingSites
    {    
        Site
        {
            name = KSC Pad
            latitude = -0.09694444
            longitude = -74.5575
            // body = "Kerbin" // if not set defaults to the starting world (Kerbin, Earth for RSS)
        }
        Site
        {
            name = VAB
            latitude = -0.09694444
            longitude = -74.617
        }
        Site
        {
            name = Desert
            latitude = -6.515573
            longitude = -144.039421
        }
        Site
        {
            name = Woomerang
            latitude = 45.289698
            longitude = 136.109897
        }    
    }
    Runways
    {
        Runway    
        {
            name = KSC Runway 09
            body = "Kerbin"
            touchdown = 100.0
            start
            {
                latitude = -0.0485981
                longitude = -74.726413
                altitude = 67
            }
            end
            {
                latitude = -0.050185
                longitude = -74.490867
                altitude = 67
            }
        }
        Runway    
        {
            name = KSC Runway 27
            body = "Kerbin" // if not set defaults to the starting world (Kerbin, Earth for RSS)
            touchdown = 100.0 // distance in meters from start point
            start
            {
                latitude = -0.050185
                longitude = -74.490867
                altitude = 67
            }
            end
            {
                latitude = -0.0485981
                longitude = -74.726413
                altitude = 67
            }
        }
        Runway    
        {
            name = Island Runway 09
            body = "Kerbin"
            touchdown = 25.0;
            start
            {
                latitude = -1.517306
                longitude = -71.965488
                altitude = 132
            }
            end
            {
                latitude = -1.515980
                longitude = -71.852408
                altitude = 132
            }
        }
        Runway    
        {
            name = Island Runway 27
            body = "Kerbin"
            touchdown = 25.0;
            end
            {
                latitude = -1.515980
                longitude = -71.852408
                altitude = 132
            }
            start
            {
                latitude = -1.517306
                longitude = -71.965488
                altitude = 132
            }
        }
        Runway    
        {
            name = Desert Runway 18
            body = "Kerbin"
            touchdown = 50.0;
            start
            {
                latitude = -6.448288
                longitude = -144.038171
                altitude = 822.05
            }
            end
            {
                latitude = 6.599329
                longitude = -144.040598
                altitude = 821.93
            }
        }
        Runway    
        {
            name = Desert Runway 36
            body = "Kerbin"
            touchdown = 50.0;
            end
            {
                latitude = 6.599329
                longitude = -144.040598
                altitude = 821.93
            }
            start
            {
                latitude = -6.448288
                longitude = -144.038171
                altitude = 822.05            
            }
        }
    }
}

******************************

 

[Space_Kadet]

I installed MechJeb2 (dev800,dev799, and the current release)

I did not get any error on loading KSP (v 1.4.3)

MJ does not show up. No Icon, nothing. anyone else has this problem?

>>> log https://www.dropbox.com/s/eq7ga83d4j110yi/KSP.log?dl=0

[El Sancho]

to begin with the obvious, have you attached a mechjeb module to your spaceship?

[Space_Kadet]

Well, ah humm, uhh <cough> <cough> I did not... 

[El Sancho]

That's OK, good buddy, we've all done it. Some of us more than once

21 hours ago, Space_Kadet said:

I installed MechJeb2 (dev800,dev799, and the current release)

I did not get any error on loading KSP (v 1.4.3)

MJ does not show up. No Icon, nothing. anyone else has this problem?

>>> log https://www.dropbox.com/s/eq7ga83d4j110yi/KSP.log?dl=0

 

56 minutes ago, Space_Kadet said:

Well, ah humm, uhh <cough> <cough> I did not... 

 

[MikeO89]

I'm trying to fly a Falcon Heavy type craft with Mechjeb and it is kicking my butt. I just can't figure out how to launch without it rolling. I'm trying to launch it to just pitch over without roll (to be in the same roll aspect it is at launch) into it's current direction with classic ascent. Even without clicking the Force Roll in Mechjeb, it's still rolls about 90°. Trying to use the Roll checkbox is driving me nuts to try to figure out what to put in there so it just pitches over with no roll. I've been putting numbers in Force Climb ___ Turn ___ but the results are not coming out the way I want and is not making sense to me. I ended up getting a successful orbit by putting in the numbers Force Climb 40°, Turn 150°. That sounds totally wrong to me but it worked. During launch, the craft rolled clockwise a little past 90°, then after that rolled the opposite direction to a position that was acceptable (keeping craft with side boosters side to side and not up and down, if that makes sense). I normally flew either a single craft with no boosters or a craft with 4 boosters and didn't pay much attention to the roll cause in the end it always came out right (or looked right anyway). Flying this craft with 2 boosters is a different animal to me cause now the roll aspect kicks me in the head. A little help from the pros would be really nice here. Thanks

Edited May 30, 2018 by MikeO89

[Space_Kadet]

9 hours ago, MikeO89 said:

I'm trying to fly a Falcon Heavy type craft with Mechjeb

I just can't figure out how to launch without it rolling.

I'm trying to launch it to just pitch over without roll

Even without clicking the Force Roll in Mechjeb, it's still rolls about 90°.

2

Rotate it 90 degrees in the VAB. (Typically, 90 Degrees Clockwise)

I was wondering the same thing with my launch scripts using kOS a while back... I was thinking, why is it rolling? I am not telling it to roll... So I rotated it 90 degrees clockwise in the VAB and it did what you are saying you want your rocket to do

9 hours ago, MikeO89 said:

I'm trying to launch it to just pitch over without roll (to be in the same roll aspect it is at launch)

1

Here are two screenshots so you know 100% exactly what I mean.

 

This rocket WILL roll 90 degrees on launch due to its orientation and what the rocket believes is 0 degrees roll

 

 

This rocket WILL NOT roll 90 degrees on launch due to its orientation, Because the rocket believe it is already at 0 degrees roll

And it is very important to notice the Kerbals in this last picture conducting a final inspection of this rockets orientation prior to flight.

Edited May 30, 2018 by Space_Kadet

[Gordon Dry]

@MikeO89 or use