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

[Gudlifer]

Hi! I have a little problem creating a script in MJ! I want to take off on the type of falcon 9, but I can not understand the script (and to be more precise, I basically do not understand how to do it). Who can throw a video or exact instructions on how to do it, please help. since the use of Kos for me an impossible task, due to the fact that the Internet I do not see ready-made scripts. What I need: Takeoff missiles\ at an altitude of 20km stops the engine 1 stage \ separation stages \ the first stage of the beginning of maneuvers to land \ the second continued to bring the spacecraft into orbit. Thank you!

Edited March 12, 2019 by Gudlifer

[Chimichanga]

Sorry to be a bother, but I still can't quite get Ascent Guidance's Launch Into Plane to work correctly... this looks to have been "fixed" in dev #865, but using current dev #872 it's still not matching inclination correctly.  It's late and I need to sleep, but I will test again with a clean KSP install tomorrow after work.  Can anyone else confirm if Launch to Plane is working correctly for them? 

[Xd the great]

6 hours ago, Chimichanga said:

Sorry to be a bother, but I still can't quite get Ascent Guidance's Launch Into Plane to work correctly... this looks to have been "fixed" in dev #865, but using current dev #872 it's still not matching inclination correctly.  It's late and I need to sleep, but I will test again with a clean KSP install tomorrow after work.  Can anyone else confirm if Launch to Plane is working correctly for them? 

I can launch to 0 and 90...

Where did you start launching from?

18 hours ago, Gudlifer said:

Hi! I have a little problem creating a script in MJ! I want to take off on the type of falcon 9, but I can not understand the script (and to be more precise, I basically do not understand how to do it). Who can throw a video or exact instructions on how to do it, please help. since the use of Kos for me an impossible task, due to the fact that the Internet I do not see ready-made scripts. What I need: Takeoff missiles\ at an altitude of 20km stops the engine 1 stage \ separation stages \ the first stage of the beginning of maneuvers to land \ the second continued to bring the spacecraft into orbit. Thank you!

You need other mods to help you do this. Something like stage recovery.

I do it like 

1. Stage

2. (parallel) start ascent guidance //  wait till altitude >20k the stage

Then use FMRS to land the first stage

[Chimichanga]

1 hour ago, Xd the great said:

I can launch to 0 and 90...

Where did you start launching from?

Thanks, sorry I forgot a completely necessary detail - I was launching to match inclination with a targeted vessel at a 30-35° inclincation

Will do additional testing when I get home from work.

Edited March 13, 2019 by Chimichanga

[Tonka Crash]

1 hour ago, Chimichanga said:

Thanks, sorry I forgot a completely necessary detail - I was launching to match inclination with a targeted vessel at a 30-35° inclincation

Will do additional testing when I get home from work.

Launch to plane should be working. It did last week. 

Launch to plane of target was still broken, but it's been a couple weeks since I last tried. The best you can do is set up a launch to plane and manually timewarp until the correct plane is aligned with your launch pad before blast off. It might take a couple attempts to get it just right if dV is critical.

[sarbian]

On 3/12/2019 at 5:25 PM, Gudlifer said:

Hi! I have a little problem creating a script in MJ! I want to take off on the type of falcon 9, but I can not understand the script (and to be more precise, I basically do not understand how to do it). Who can throw a video or exact instructions on how to do it, please help. since the use of Kos for me an impossible task, due to the fact that the Internet I do not see ready-made scripts. What I need: Takeoff missiles\ at an altitude of 20km stops the engine 1 stage \ separation stages \ the first stage of the beginning of maneuvers to land \ the second continued to bring the spacecraft into orbit. Thank you!

The MJ scripting is very basic and can only control one stage. So what you ask for is not doable. Also I read post here so there is no need to also post on my profile and PM me in Russian at the same time.

 

Launch to plane of targe requires the game to know how long it takes for your rocket to ascent. So you need to launch once and revert so the launchPhaseAngle is properly setup. Something else might be broken but you need to check that first.

[Tonka Crash]

2 minutes ago, sarbian said:

Launch to plane of targe requires the game to know how long it takes for your rocket to ascent. So you need to launch once and revert so the launchPhaseAngle is properly setup. Something else might be broken but you need to check that first.

I just went to test this and it seems to be launching to the correct inclination, but not waiting to for the target orbit to move over the launch site.

I select a target in an inclined orbit around Kerbin (phase angle and target inclination are both filled in and seem reasonable), select launch to plane of target (Orbit Inc box fills in with the correct inclination) , hit engage autopilot, and the rocket lifts off immediately there is no timewarp for the targeted orbit to move overhead. Reverting to launch after an reaching orbit does not change behavior of subsequent launches..

 

On a different topic I've been meaning to bring up: (1.6.1 and whatever the latest dev build is) Lately I've been having trouble with rockets circularizing orbits after launch and sometimes  just getting oriented for maneuver nodes on time. It seems like the mechjeb has reduced the control authority it uses for reaction wheels so that I'm missing maneuver nodes on heavier rockets that used to work just fine. I first noticed this on launches. While my rockets are coasting to Ap they are not rotating enough to aim prograde in time for a burn as they approach Ap. If I help them by holding nose down pitch they make it easily and it will time warp to Ap before the burn. I've noticed the same problem orienting for once in orbit maneuver nodes. I have to help steer to get the nose pointed in time. It's typically heavier rockets. I can always throw more reaction wheels at the problem, but it seems like the behavior changed sometime in the last couple weeks.

 

 

[dlrk]

I can get logs, etc, if needed, but just asking off the cuff, what does it mean if the suicide burn countdown is greater than time to impact?

[GoatRider]

3 minutes ago, dlrk said:

I can get logs, etc, if needed, but just asking off the cuff, what does it mean if the suicide burn countdown is greater than time to impact?

That seems right to me- if you're burning, you're going to be slowing down, so it will take longer to get to the ground than if you were just going to let it go.

EDIT- oh you mean the time to START the suicide burn? Yeah, that would be a problem.

Edited March 13, 2019 by GoatRider

[dlrk]

Uh, no. Suicide burn countdown greater than to impact would have me hitting the ground before I start decelerating.

[Chimichanga]

On 3/13/2019 at 2:58 PM, sarbian said:

Launch to plane of targe requires the game to know how long it takes for your rocket to ascent. So you need to launch once and revert so the launchPhaseAngle is properly setup. Something else might be broken but you need to check that first.

I thought this was only for Launch to Rendezvous - in the past I used to use Launch to Plane successfully to get around having to revert when using Launch to Rendezvous - anyway I am home and will start mucking around trying to get a good baseline to submit logs.

 

EDIT: Reverting to launch does not fix the issue - first launch was 12° off target, second launch was 8.5° off target.  Will continue doing this by eye / using Engineer Redux for determining rendezvous angles at launch.

Edited March 16, 2019 by Chimichanga

[Jim DiGriz]

6 hours ago, Tonka Crash said:

On a different topic I've been meaning to bring up: (1.6.1 and whatever the latest dev build is) Lately I've been having trouble with rockets circularizing orbits after launch and sometimes  just getting oriented for maneuver nodes on time. It seems like the mechjeb has reduced the control authority it uses for reaction wheels so that I'm missing maneuver nodes on heavier rockets that used to work just fine. I first noticed this on launches. While my rockets are coasting to Ap they are not rotating enough to aim prograde in time for a burn as they approach Ap. If I help them by holding nose down pitch they make it easily and it will time warp to Ap before the burn. I've noticed the same problem orienting for once in orbit maneuver nodes. I have to help steer to get the nose pointed in time. It's typically heavier rockets. I can always throw more reaction wheels at the problem, but it seems like the behavior changed sometime in the last couple weeks.

In the "Attitude Adjustment" make sure you have "Hybrid Controller" selected, and set "MaxStoppingTime" to 10.

If you then start to notice that when docking, etc using RCS that it uses piles and piles of monoprop you'll need to set it back down to 2.

Difficult to autotune that one based on whatever anyone might be doing with any rocket, so you need to manually tweak that sometimes.

6 hours ago, Tonka Crash said:

I select a target in an inclined orbit around Kerbin (phase angle and target inclination are both filled in and seem reasonable), select launch to plane of target (Orbit Inc box fills in with the correct inclination) , hit engage autopilot, and the rocket lifts off immediately there is no timewarp for the targeted orbit to move overhead. Reverting to launch after an reaching orbit does not change behavior of subsequent launches..

Just tried this with the "classic" ascent targeting the moon, and went through that exact process and it warped fine.

[Friznit]

It seems to be a sporadic issue.  I'm also occasionally experiencing MJ launching immediately and heading at 90 deg instead of time warping and launching to the correct inclination.  There's definitely some weirdness going on but I can't find anything relevant in the logs.  I'd say it's almost guaranteed to be a mod conflict somewhere but it's a tough one to nail down.

[Jim DiGriz]

That really sounds like the old bug.  Make absolutely certain that you've upgraded and that you only have one MechJeb.dll in your GameData and that the folder layout looks correct.

[Nicias]

I think something is wrong with the dV calculator.

If you just put a poodle, X200-32, and RC-001S  together, the dV calculator reports a dV of 11259 and a run time of 439.3 seconds. Both are almost exactly twice as large as they should be.

If you just use a RC-001S, Nerv, and Mk1 LF fuesalge, MechJeb reports 3305 dv and a run time of 235.3 seconds. Both are about 90% of what they should be.

This is with a bare 1.5.1 install with just MJ-dev (and MJ for all) installed.

Edited March 15, 2019 by Nicias
more info

[Chimichanga]

8 hours ago, Nicias said:

I think something is wrong with the dV calculator.

If you just put a poodle, X200-32, and RC-001S  together, the dV calculator reports a dV of 11259 and a run time of 439.3 seconds. Both are almost exactly twice as large as they should be.

If you just use a RC-001S, Nerv, and Mk1 LF fuesalge, MechJeb reports 3305 dv and a run time of 235.3 seconds. Both are about 90% of what they should be.

This is with a bare 1.5.1 install with just MJ-dev (and MJ for all) installed.

Can confirm this issue on dev #875, 1.6.1 w/ MH

Edited March 15, 2019 by Chimichanga

[El Sancho]

I also confirm the business of MJ showing double the Delta-V reported by KSP itself.

On the subject of launch to plane, I was having all sorts of weirdness and inconsistent behaviour. Then I tried Jim's suggestion above. I nuked my existing MJ2 directory in C:\Program Files (x86)\Steam\steamapps\common\Kerbal Space Program\GameData and did a fresh reinstall from the archive of ver 875 and now it seems to work fine.

My tentative conclusion is that my habit of updating MJ by simply dragging the MJ2 directory from the new archive to GameData and choosing "overwrite all files" is not sufficient. Some vestige of an old version was apparently remaining and ****ing things up.

[Jim DiGriz]

On 3/16/2019 at 4:40 PM, El Sancho said:

I also confirm the business of MJ showing double the Delta-V reported by KSP itself.

On the subject of launch to plane, I was having all sorts of weirdness and inconsistent behaviour. Then I tried Jim's suggestion above. I nuked my existing MJ2 directory in C:\Program Files (x86)\Steam\steamapps\common\Kerbal Space Program\GameData and did a fresh reinstall from the archive of ver 875 and now it seems to work fine.

My tentative conclusion is that my habit of updating MJ by simply dragging the MJ2 directory from the new archive to GameData and choosing "overwrite all files" is not sufficient. Some vestige of an old version was apparently remaining and ****ing things up.

You may have wound up with a MechJeb directory inside your MechJeb directory, so both GameData/MechJeb2/Plugins/MechJeb2.dll and GameData/MechJeb2/MechJeb2/Plugins/MechJeb2.dll both existed or something, and then who knows which dll gets wired up right.

And if anyone is reading this and blowing away their MJ folder and reinstalled from scratch the GameData/MechJeb2/Plugins/PluginData/MechJeb2 is where all the settings are -- just save and restore that however you like.

On 3/15/2019 at 2:42 PM, Chimichanga said:

Can confirm this issue on dev #875, 1.6.1 w/ MH

confirmed in 1.3.1, but i saw this way too late to start worrying about fixing it tonight.

[Jim DiGriz]

On 3/17/2019 at 9:06 PM, Jim DiGriz said:

confirmed in 1.3.1, but i saw this way too late to start worrying about fixing it tonight.

Should be fixed in #877

[Jim DiGriz]

Other nuts and bolts stuff that has gone into #877 and leading up to it:

- Goodings Lambert method got debugged, which may impact some of the accuracy of the porkchop predictions in the advanced transfer planner (or rather may have fixed some bugs that were reported about inaccuracies in the porkchop plot)

- The non-simple biimpulsive transfer planner has had a ton of bugfixing and should work now much more reliably.  Specifically:

* it is now a basin-hopping algorithm instead of simulated annealing (although its probably not terribly well tuned and there's still some annealing-style code in it)

* it uses the (debugged) Gooding solver

* it is wired up to Shepperd's method for keplerian propagation

* several crazy bugs that would have rendered it pretty much unusable got fixed

It is now fairly close to being able to calculate the primer vector trajectory using Shepperd's method along the path and analyze it for optimality, which will lead to implementing Jezewski's algorithm for generating optimal N-impulse transfer trajectories (read:  MechJeb will be able to figure out optimal mid course corrections -- although not interplanetary ones --  in the somewhat near future).

Edited March 19, 2019 by Jim DiGriz

[Tacombel]

I can only say, brilliant!!!!

[Jim DiGriz]

And maybe to head off a question about the new biimpulsive transfer planner code -- it still isn't wired up with UX to support manual entering of the search criteria.  That means that for certain cases it comes up with optimal-but-not-what-i-wanted trajectories.  So from a parking orbit to intercept a hyperbolic asteroid orbit, it will prefer to intercept at the SOI exit of the hyperbolic orbit because that is minimal delta v, but maximally useless if you wanted to burn at the periapsis of the hyperbolic orbit to capture it.  Gotta get the basic algorithm working though before adding tons of knobs and dials to it and crawl before you walk before you run and all that...

[Xd the great]

How can I reduce the AoA of plane autopilots? Especially the landing system.

 

[El Sancho]

On 3/19/2019 at 2:48 AM, Jim DiGriz said:

It is now fairly close to being able to calculate the primer vector trajectory using Shepperd's method along the path and analyze it for optimality, which will lead to implementing Jezewski's algorithm for generating optimal N-impulse transfer trajectories (read:  MechJeb will be able to figure out optimal mid course corrections -- although not interplanetary ones --  in the somewhat near future).

I teach English online, and much of my working day consists of waiting for students. So, given that my major was Political Science and some of this stuff goes waaaaayyyy over my head, I decided to look up this Jezewski's algorithm just on the basic principle of self-education. When I Googled it, I found to my amusement that the first results are related to "uterine contractions and fetal heartrate". Apparently this is the work of Janusz Jezewski, whereas the rocket-related stuff is the work of D.J. Jezewski. The rocket stuff does show up further down the page, but my initial reaction was along the lines of, "Ahhhh, Whiskey Tango Foxtrot, Jim?"

Edited March 21, 2019 by El Sancho

[Deltac]

I've done my best to try and find info on Mechjeb and Space Shuttles' offset center of mass/thrust in space, but I'm finding a lack of info.  If the center of thrust and mass are aligned in a space shuttle, but off center from the rest of the craft, can Mechjeb point the shuttle so that the center of thrust/mass are pointing at the maneuver node?