MechJeb Autom8 Scripts Megathread

[Glaucus]

is there anyway to control throttle with this? couldn't see anything in the manual

[olex]

Use the followong:

mechjeb.thrustActivate(0-100)
mechjeb.thrustDeactivate()

It appears not to be documented, but it's used in my Mun return script if you want an example.

[Glaucus]

Thank you, great stuff.

[squirrle4620]

is it possible to make a script to automatically change the inclination of an orbit while in that orbit? or does mechjeb already have a way i can do this and i'm just too dense?

[khmnc]

is it possible to make a script to automatically change the inclination of an orbit while in that orbit? or does mechjeb already have a way i can do this and i'm just too dense?

it is possible to make a script to automatically do it. i have actually been working on one for over a week now but i have a problem in my equations somewhere >_<

[Nadrek]

it is possible to make a script to automatically do it. i have actually been working on one for over a week now but i have a problem in my equations somewhere >_<

If I may ask, I was waiting to even try this until I can warp to the ascending or descending node - have you actually worked out the amount of time from apoapsis/periapsis to the ascending/descending node for elliptical orbits, or are you using a different technique?

My plan would have been to try and figure out the delta-V required, then do a burn anticipated to reach it, possibly with some fudge factor and touch-up afterwards for the highest accuracy, and possibly multi-orbit based if the thrust available isn't high enough.

[calhoun1]

OK I am currently using the FlyMeToTheMun(45,45) script.

I launched and reached 125km orbit successfully. Now I have been warping to SOI for 4 (edit: now 7) kerbal days. How long will I need to wait for the SOI? Do I need to abort and retry? This is my first shot at getting to the Mun and have no clue if I am doing it right.

I also have tried some forum searches and found nothing. Thanks!

Edit- And after I post this, now I have transitioned to warping to Periapsis. Of course the Pe keeps moving slightly, so it is taking a while as well. Hopefully I am doing this right!

Edit - And now it just tried to land on Kerbin without ever transferring to the Mun. Not sure what I did wrong.

Edited September 2, 2012 by calhoun1

[squirrle4620]

Sweet! Could you provide your source code so I can give it a look over? I like bug hunting!

[calhoun1]

I used the file as written. Not sure what I did wrong.

[khmnc]

If I may ask, I was waiting to even try this until I can warp to the ascending or descending node - have you actually worked out the amount of time from apoapsis/periapsis to the ascending/descending node for elliptical orbits, or are you using a different technique?

My plan would have been to try and figure out the delta-V required, then do a burn anticipated to reach it, possibly with some fudge factor and touch-up afterwards for the highest accuracy, and possibly multi-orbit based if the thrust available isn't high enough.

my plan was to calculate the position of the burn nodes, calculate the time until the craft reached the nearest one, warp to it, calculate the amount of time and the amount of thrust needed, make the burn until the amount of time needed has elapsed or it is too far from the burn point, then redo the calculations to see if another burn is needed

so far my equations get within 12% of the target position, which is unacceptable

[Nadrek]

my plan was to calculate the position of the burn nodes, calculate the time until the craft reached the nearest one, warp to it, calculate the amount of time and the amount of thrust needed, make the burn until the amount of time needed has elapsed or it is too far from the burn point, then redo the calculations to see if another burn is needed

so far my equations get within 12% of the target position, which is unacceptable

Hmm; I'd have to wonder if you redid all your calculations after the warp (and noted the differences), and if you accounted for thrust ramp-up and ramp-down time and the change in attitude required during the burn.

When you say within 12%, are you always under, always over, or sometimes some of each?

May I also ask how you warped to the nearest burn node?

[Nadrek]

SimpleKSPOrbitalMechanics upgraded to 0.003 and SimpleKSPOrbitalOperations upgraded to 0.002; see post #53 in this thread for more details (now includes function listings!).

http://kerbalspaceprogram.com/forum/showthread.php/16503-MechJeb-Autom8-Scripts-Megathread?p=238962&viewfull=1#post238962

Togfox, there's code to calculate actual measured Isp (at whatever throttle setting you like) from any rocket you can get into stable orbit. You could then calculate exhaust velocity from this and feed it into your delta-V calculator if you still don't like mine . Try it on every stage for fun and profit .

Added KSP based isOrbitStable, reporting on orbital and mass variables instantaneously and over time(!), and operational testing of actual Isp at various thrust settings. Skoo now has functional code to detect when mechjeb.attitudeTo() has finished pointing.

New Skom functions:

isSkomCurrentOrbitStable()

reportSkomCurrentMsMsdApPeSopTmapTmpeLanAopIncEccAOvSvVvHvHdPiRlAltaslAlttruAltbotLatLngRfcbGAtmdTm()

reportSkomCurrentChangeOverTimeMsiMsfMsMsdApPeSopTmapTmpeLanAopIncEccAOvSvVvHvHdPiRlAltaslAlttruAltbotLatLngRfcbGAtmdTmFromTmbiTmbtwnDriver(TimeBeforeInitial, TimeBetween)

printSkomCurrentChangeOverTimeMsiMsfMsMsdApPeSopTmapTmpeLanAopIncEccAOvSvVvHvHdPiRlAltaslAlttruAltbotLatLngRfcbGAtmdTmFromTmbiTmbtwnDriver(TimeBeforeInitial, TimeBetween)

coprintSkomCurrentChangeOverTimeMsiMsfMsMsdApPeSopTmapTmpeLanAopIncEccAOvSvVvHvHdPiRlAltaslAlttruAltbotLatLngRfcbGAtmdTmFromTmbiTmbtwn(TimeBeforeInitial, TimeBetween)

New Skoo functions:

measureSkooIspFromTmbiTmbtwnNsDriver(TimeBeforeInitial, TimeBetweenEach, NumberSlices)

testSkooIspFromTmbiTmbtwnNsMpcsDriver(TimeBeforeInitial, TimeBetweenEach, NumberSlices, MaxPointingChangeStable)

cotestSkooIspFromTmbiTmbtwnNs(TimeBeforeInitial, TimeBetweenEach, NumberSlices)

cotestSkooIspFromTmbiTmbtwnNsMpcs(TimeBeforeInitial, TimeBetweenEach, NumberSlices, MaxPointingChangeStable)

[togfox]

Togfox, there's code to calculate actual measured Isp (at whatever throttle setting you like) from any rocket you can get into stable orbit. You could then calculate exhaust velocity from this and feed it into your delta-V calculator if you still don't like mine . Try it on every stage for fun and profit .

I had considered doing that - that will remove one of my parameters - a pretty important one mind you. That means "fuel left" would be the only manually entered input - and that's available in-game with a right-mouse-click.

[Nadrek]

I had considered doing that - that will remove one of my parameters - a pretty important one mind you. That means "fuel left" would be the only manually entered input - and that's available in-game with a right-mouse-click.

There's a userecho request for it to be in-game, per stage, to the lua code.

Alternately, at the design stage, write down the amount of fuel per stage in mass units, and then feed your code one parameter - the dry mass of the rocket, and then it can calculate fuel from the wet mass... as long as you don't use more than one fuel type (i.e. RCS).

[sanderlebau]

Has anyone written a program to travel to a given lat, lon? For example, I'm trying to circumnavigate the globe, and now that you cannot accelerate time while in the atmosphere, I'd like to automate some of the longer crossings without worrying about over-shooting and crashing into land. Has anyone written such a program?

[j-tk]

Hopefulyl this is what you were looking for to help ( A HUGE thank yuo to you and the rest of this community, you guys are awesome!) This is from the webpage directly, copied, and put in thru notepad++

1.
--

 2.
--         Mun to Kerbin Return Script by olex

 3.
--                    Version 1.0

 4.
--

 5.
--                 for MechJeb 1.9.1

 6.
--

 7.
--------------------------------------------------------

 8.
-- Usage: * save to KSP/PluginData/mumechlib/GoHome.lua

 9.
--        * in game, open autom8

 10.
--        * enter: dofile("GoHome.lua")

 11.
--        * and follow the instructions.

 12.
--

 13.
-- Quicksave before using.

 14.
-- If an "coroutine out of sync" error pops up, load the save and try again.

 15.
--

 16.
-- No guarantees, but it should work  Have fun!

 17.
--------------------------------------------------------

 18.


 19.
function KerbinReturnDriver(pe)

 20.
        if pe == nil then

 21.
                pe = 20.0

 22.
        end

 23.
        if pe > 70 then

 24.
                print "Final periapsis not in atmosphere, no automatic landing."

 25.
        end

 26.


27.
        print "Lifting off..."

 28.
        mechjeb.attitudeTo("up", "SURFACE_NORTH") -- vertical ascent

 29.
        mechjeb.thrustActivate(100)

 30.
        while vessel.altitudeTrue < 300 do

 31.
                wait(0.25)

 32.
        end

 33.


34.
        print "Escaping the Mun..."

 35.
        -- this needs to be optimized. figure out an escape vector

 36.
        -- that is as close as possible to the opposite of Mun's orbital velocity

 37.
        -- but not lower than 0° to the surface

 38.
        mechjeb.attitudeTo("right", "SURFACE_NORTH") -- heading east

 39.
        while vessel.orbitEccentricity < 1 do

 40.
                wait(0.25)

 41.
        end

 42.
        mechjeb.thrustDeactivate()

 43.


44.
        print "Coasting to Mun escape, hang on."

 45.
        mechjeb.warpToEvent("soi")

 46.
        wait(mechjeb.free)

 47.


48.
        print("Lowering Kerbin periapsis to "..pe.."km...")

 49.
        mechjeb.changePe(pe * 1000)

 50.
        wait(mechjeb.free)

 51.


52.
        print "Coasting to Kerbin, stand by."

 53.
        mechjeb.warpToEvent("pe")

 54.
        while vessel.atmosphericDensity <= 0 and (not mechjeb.free()) do

 55.
                wait(0.25)

 56.
        end

 57.
        mechjeb.controlRelease()

 58.


59.
        if vessel.atmosphericDensity > 0 then

 60.
                print "Re-entry... hold onto something."

 61.
                mechjeb.attitudeTo("back", "ORBIT")

 62.
                while vessel.speedSurface > 250 do

 63.
                        wait(0.1)

 64.
                end

 65.
                print "Landing."

 66.
                mechjeb.autoStageActivate()

 67.
                mechjeb.land()

 68.
                wait(mechjeb.free)

 69.
                mechjeb.autoStageDeactivate()

 70.
                print "Welcome home!"

 71.
        else

 72.
                print "Not in atmosphere at periapsis. We're done here."

 73.
        end

 74.
end

 75.


 76.
function GoHome(pe)

 77.
        local co = coroutine.create(KerbinReturnDriver)

 78.
    coroutine.resume(co, pe)

 79.
end

 80.


 81.
print "Usage: GoHome(<desired Kerbin periapsis in km, default 20>)"

[Nadrek]

Again, thanks to the KSP and Mechjeb teams for providing us with such an exciting toolbox to play with in an easily written and scripted interpreted language. With little more than KSP, Mechjeb, a text editor, and some typing we can land on the Mun, get into a Molniya orbit, or perform most other manuevers.

I think I may be running into either mechjeb.* data limit, or a limit in my vocabulary, as I'm rapidly approaching a stalling point where I have almost, but not quite, all the orbital elements. to do more math and then more operations with.

I'm asking for help in gathering the following information, either directly or by pointing out the elements I have that I can use to derive the following:

A. Mean Anomaly at Epoch and units (or any of the related anomalies - Mean Anomaly, True Anomaly, perhaps the Eccentric Anomaly)

EDIT: A.1 in Kerbin Orbital Parameters V2 (https://docs.google.com/document/d/1fmTW6P91OVFj5Tuj0JzKcnfpcw79RqveQTAywrPIIrI/edit?pli=1#heading=h.ktf15rmlbwy8) I see a formula that says it's for Mean Anomaly at Epoch based solely on semi-major axis, the standard gravitational parameter, and time since periapsis. My questions now becomes: is that correct, Epoch is strictly arbitrary (i.e. the first step in any set of formulas that use Epoch is to synchronize Epochs, and/or set them all to a reference value, like - arbitrarily - vessel.time = 0)? I'm still seeking the formulas and elements for circles, equatorial circles, parabolas, and hyperbolas, though.

B. True longitude (is it the same as vessel.longitude) and units

C. True latitude (is it the same as vessel.latitude) and units

Or, alternately:

D. Position Vector and units

E. Velocity Vector and units

F. Frame of reference and units

G. Any recommended pure lua library for matrix and vector math to code the conversions with .

Some references on equations I'd like to be able to use (True Anomaly or other values required): http://kerbalspaceprogram.com/forum/showthread.php/10037-Getting-Absolute-Longitude-%28in-same-reference-system-as-LAN%29?p=216289&viewfull=1#post216289

Edited September 6, 2012 by Nadrek
Learned more, amended A

[OdinYggd]

Chance question- can mechjeb's autom8 fire off events from other modules, such as the orbital construction mod's transfer cargo feature?

Was thinking about making a script that would launch an unmanned cargo vessel, approach spacedock, transfer cargo, and then deorbit to crash land. Or if I felt up to it, return to KSP after delivering the cargo.

[Nadrek]

From the UserEcho, I found 'access the C# class with mechjeb.core.targetVessel"

1) What's the companion way of getting to a body, like the Mun, Minmus (Eve), etc.?

2) Is there one of the C# files from the svn repository I can ready to see what options I have for mechjeb.core.*, or mechjeb.core.targetVessel? Or a way in lua to enumerate all the possible options? I hate asking silly questions like these.

In MechJeb 1.9.1, I popped up the Rendevous module, selected a Vessel from the Spacecraft exchange at 1200km distance, and tried:

> print(mechjeb.core.targetVessel.speedOrbital)

receiving:

Exception: Cannot get speedOrbital from Talos-MKII Debris (unloaded) (Vessel)

So it's reading the target correctly, but I don't know how to use it . I then selected the Mun, and tried again - still pointed at the Talos debris (unsurprisingly)

[r4m0n]

From the UserEcho, I found 'access the C# class with mechjeb.core.targetVessel"

1) What's the companion way of getting to a body, like the Mun, Minmus (Eve), etc.?

2) Is there one of the C# files from the svn repository I can ready to see what options I have for mechjeb.core.*, or mechjeb.core.targetVessel? Or a way in lua to enumerate all the possible options? I hate asking silly questions like these.

In MechJeb 1.9.1, I popped up the Rendevous module, selected a Vessel from the Spacecraft exchange at 1200km distance, and tried:

> print(mechjeb.core.targetVessel.speedOrbital)

receiving:

Exception: Cannot get speedOrbital from Talos-MKII Debris (unloaded) (Vessel)

So it's reading the target correctly, but I don't know how to use it . I then selected the Mun, and tried again - still pointed at the Talos debris (unsurprisingly)

1 - mechjeb.core.targetBody

2 - http://svn.mumech.com/KSP/trunk/MuMechLib/MechJebCore.cs

Note that targetVessel is a C# Vessel object, not a VesselState like the Lua "vessel" variable. What you wanted would be mechjeb.core.targetVessel.orbit.orbitalSpeed.

[Nadrek]

Excellent - thank you, r4m0n! I was able to determine many of the relevant values by guesswork.

Unfortunately, in any of the .cs files, looking for even "orbitalSpeed" did not turn up anything other than part.vessel.orbit.getOrbitalSpeedAt(timeLeft), which I couldn't figure out in Lua by guesswork.

Is there another place to look for the contents of the C# Vessel (and Body) object? I'm sorry for the basic questions.

If anyone else can use it, here's a list of the additional functionality I've read on the forums/userecho, or found based on r4m0n's help so far:

Undocumented commands:
mechjeb.stage() 
  increments stage, just like hitting space bar
mechjeb.controlRelease() 
  deactivates the .attitudeTo(), .thrustActivate() and perhaps other commands
mechjeb.thrustActivate(Percentage)
  sets engines to that level
mechjeb.thrustDeactivate()
  turns off engines
mechjeb.warpIncrease()
  increases warp factor by 1
  Returns True if the warp increase succeeded, False if it failed
mechjeb.warpDecrease()
  decreases warp factor by 1
  Safe to re-run when at 0
  Always returns nil
mechjeb.warpPhysics()
  0.16 - sets warp to 1x
mechjeb.warpMinimum()
  0.16 - sets warp to 1x
mechjeb.getAttitudeActive()
  returns boolean - apparently whether Smart A.S.S. or a similar attitude hold is in effect
mechjeb.attitudeDeactivate()
  disables .attitudeTo() and/or Smart A.S.S. without changing thrust.

var = mechjeb.getModule(ModuleName)
  ??
mechjeb.attitudeGetReferenceRotation(??)
  ??
mechjeb.attitudeWorldToReference(??)
  ??
mechjeb.attitudeReferenceToWorld(??)
  ??
mechjeb.attitudeAngleFromTarget(??)
  ??
mechjeb.distanceFromTarget(??)
  ??
mechjeb.relativeVelocityToTarget(??)
  ??
mechjeb.targetName(??)
  ??
mechjeb.landActivate(??)
  ??
mechjeb.landDeactivate(??)
  ??
mechjeb.launch(??)
  ??
mechjeb.mechjeb.getControlClaimed()
  ?? - returns False even with both Smart A.S.S./.attitudeTo() and .thrustActivate() active

EITHER mechjeb.core.targetVessel (select target Vessel or Debris, NOT Bodies, in Rendevous Module GUI)
OR mechjeb.core.targetBody (select target Celestial Body in Rendevous Module GUI)
  .orbit.orbitalSpeed
  Example: print(mechjeb.core.targetBody.orbit.orbitalSpeed)
  returnsTarget orbital speed in m/s 

  mechjeb.core.targetBody.orbit.orbitalSpeed
    returns Target orbital speed in m/s
  .latitude (targetVessel ONLY!!!)
    returns Target latitude in ??
  .longitude (targetVessel ONLY!!!)
    returns Target longitude in ??
  .orbit.semiMajorAxis
    returns Target semi-major axis in meters
  .orbit.LAN
    returns Target LAN in degrees
  .orbit.eccentricity
    returns Target 
  .orbit.argumentOfPeriapsis
    returns target Argument of Periapsis in degrees
  .orbit.altitude
    returns target ??(ASL?  Bottom?  True?  Other?) altitude in meters
  .orbit.ApA
    returns target Apoapsis in meters
  .orbit.PeA
    returns target Periapsis in meters
  .orbit.inclination
    returns target Inclination in degrees
  .orbit.period
    returns target Period in seconds
  .orbit.timeToPe
    returns target time to Periapsis in seconds
  .orbit.timeToAp
    returns target time to Apoapsis in seconds
  .orbit.radius
    returns orbital radius (from center of body being orbited) in meters
  .CoM[1]  (targetVessel ONLY!!!)
    returns ??
  .CoM[2]  (targetVessel ONLY!!!)
    returns ??
  .CoM[3]  (targetVessel ONLY!!!)
    returns ??

[togfox]

Nice. Rep points for you.

[TwiggyShip]

Might I ask how to save as an .lua file? It downloads and saves as just a .txt for me..?

[sal_vager]

TwiggyShip, have you tried renaming the file extension to .lua ?

[TwiggyShip]

I have, and it is still a .txt document.