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[WIN/MAC/LINUX] KSP Trajectory Optimization Tool v1.6.9 [New MATLAB Version!]


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9 hours ago, Drew Kerman said:

hey @Arrowstar I just noticed that all the Outer Planet Mod bodies except the moon Hale show up in the celestial body catalog with Epoch values hours or even days ahead of 0 like all the stock planets. I'm not sure why - could this be a KSPTOT issue or maybe something with Kopernicus? I created a new game so the UT was 0 and imported body values from it, but the catalog (and in fact the rendezvous planner) show Epoch values greater than 0. I mean, it's not really a huge issue cause no one is going to get out there in a few hours or days to need to know where the bodies are before then, but I also can't figure out why these bodies would have a starting Epoch that is not 0.

The epoch is whatever is specified by the mod designer. It doesn't matter too much, KSPTOT can figure out celestial body positions before and after any epoch. :-) 

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18 minutes ago, Drew Kerman said:

wrong thread

Quote

Q: I can't get the KSP TOT real time system or maneuver node upload to connect. What can I do?

A: Check the following conditions: KSP must be running in a windowed mode, you must be in the flight scene (not tracking station or space center scene, but the scene where you can fly your vessel), and you must have a firewall exception for KSP. If these are all true and you're still having problems, let me know.

 

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5 minutes ago, Gordon Dry said:

 

 

3 hours ago, Gordon Dry said:

Why does it have to be in windowed mode?

This fiddling with OpenGL or DirectX11 or -popupwindow or not or Fullscreen = True or False etc. is so weird....

You can certainly try it in full screen mode!  Let me know what you find. :-) I've had issues in the past is all, but that was a long time ago. 

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That coordinate system for reference spacecraft is a great idea! I look forward to trying it out. I think I'll be starting by using it when putting relay satellites into regularly spaced orbits. Should be much easier to see what's going on now :)

Edited by Snoman314
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On 5/5/2017 at 7:26 PM, Snoman314 said:

That coordinate system for reference spacecraft is a great idea! I look forward to trying it out. I think I'll be starting by using it when putting relay satellites into regularly spaced orbits. Should be much easier to see what's going on now :)

It is!  I'll have a pre-release out at some point soon and you can try it out then. :)

----------------------------------------------------------------------------------

And I'll just leave this here....  The next version is getting another cool feature.

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whenever people ask me why I'm taking so long to do stuff I tell them it's not just because of "realism" it's cause the longer I wait the more awesome KSP stuff gets! :P

So this isn't a full-on launch planner as you originally had going but does at least give you an idea of how to setup an injection orbit from launch to get a craft where it needs to be to start a mission you planned?

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45 minutes ago, Drew Kerman said:

So this isn't a full-on launch planner as you originally had going but does at least give you an idea of how to setup an injection orbit from launch to get a craft where it needs to be to start a mission you planned?

Correct. The trajectory it provides is reasonably realistic but it is only an approximation. If you have a rocket that you know something about, you can use that knowledge along with information about launch site and desired altitude to see roughly what your rocket might do, and more importantly what kind of orbit you might end up in. It's just another way to get a mission started without having to know exactly what orbit you'll be in once you get to space. This helps you figure that out. 

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18 hours ago, Phineas Freak said:

Oh god, this will make direct ascent profiles so much easier...thank you very much for adding that feature! :D

So just as a warning, this only injects you into a circular parking orbit.  The math for anything else is beyond the scope of what I'm trying to achieve here, and I would like to keep it simple for users.  Most people inject into circular parking orbits anyway, so it's applicable in many cases.  And if it's not, then you can set the state directly.  I am working on setting up optimization variables for the "set state directly" part of the UI.  Should have a pre-release version with all this to play with by the end of this weekend. :)

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1 minute ago, Drew Kerman said:

would it still be helpful using the direct state method to setup something like a New Horizons launch that just flew straight out of the system?

I'm not entirely sure what you're asking, but I think... Yes? :-) 

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2 hours ago, Arrowstar said:

I'm not entirely sure what you're asking, but I think... Yes? :-) 

the New Horizons probe to Pluto did not enter into orbit around Earth, it launched into a hyperbolic trajectory - I understand it was the fastest probe to leave the system. Looking to do something similar for my early interplanetary probes

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21 minutes ago, Drew Kerman said:

he New Horizons probe to Pluto did not enter into orbit around Earth, it launched into a hyperbolic trajectory

Umm...no:

Quote

"29 minutes and 59 seconds after liftoff, Centaur re-ignited its engine on a burn of nine minutes and 27 seconds to boost the vehicle out of Earth orbit, targeting a velocity of 12.4 Kilometers per second at the cutoff of Centaur 39 minutes and 26 seconds into the flight. Nineteen seconds after Centaur engine shutdown, the Star 48B upper stage was released for ignition of its Solid Rocket Motor at T+40:15. Star 48B completed a spin-up just before ignition and fired its rocket for 86 seconds to give the final boost to New Horizons. The spacecraft was separated from the upper stage 44 minutes and 55 seconds after liftoff at an injection speed of 16,204 meters per second – setting a new record for the fastest man-made object sent into space."

Source: Spaceflight101

And another one, "more official" (page 30): http://www.boulder.swri.edu/pkb/ssr/ssr-mission-design.pdf

Generally, direct ascent profiles are so limiting that were done only because there was no other way. Limited ignitions, not reliable engines, tight mass limits were some of the factors of the early Pioneer, Luna, Surveyor, Mariner, Ranger (and even more) missions. IIRC the last mission to use something like that was back in the '60s.

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29 minutes ago, Phineas Freak said:

Limited ignitions, not reliable engines, tight mass limits were some of the factors of the early Pioneer, Luna, Surveyor, Mariner, Ranger (and even more) missions

yea, that's why I was considering doing this for my early interplanetary probes. Huh, I guess I must have read too fast when first learning about how New Horizons was launched. I stand corrected!

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3 minutes ago, Drew Kerman said:

yea, that's why I was considering doing this for my early interplanetary probes.

Interplanetary is relatively easy compared to Lunar direct ascents. They usually have a launch window spanning several days (instead of just minutes), since you don't need to be well aligned with the plane of the Moon and larger phase angles. Minor corrections done early can also fix some of the launch trajectory anomalies.

The most difficult thing would be to have an Altair or STAR motor as an escape stage. Now...you have to trim the trajectory and the payload mass to be just right. Not too little and not too much.

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1 hour ago, Drew Kerman said:

the New Horizons probe to Pluto did not enter into orbit around Earth, it launched into a hyperbolic trajectory - I understand it was the fastest probe to leave the system. Looking to do something similar for my early interplanetary probes

Okay, so you can actually do this now without having to optimize the initial state.  Say you want to go to Duna from Kerbin:

  1. Use the porkchop plot and Compute Departure button to find the basic departure plan.
  2. On the Compute Departure window, find the top textbox that shows the outbound hyperbolic orbit.  Locate the hyperbolic excess velocity vector components in that box, as well as the magnitude.
  3. In Mission Architect, set up a new mission and use whatever initial orbit you want.
  4. Add coast and DV maneuver.
  5. Optimize the coast and DV maneuver with no objective function (satisfy constraints only) and set four constraints, one for each of the excessive velocity vector components you grabbed in step (2) plus the magnitude.
  6. Push Optimize.
  7. Go through the normal "target a body to land on" sequence from here.

You can get your hyperbolic departure orbit from after step (6), so basically the parking orbit is only fictitious if you don't want to use it.  Launching into that hyperbolic orbit is up to you, though, MA can't do that for you. :)

 

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Hi everyone!

Good news!  I have a new pre-release of 1.5.7 for people to play around with and take a look at.  Here's the feature set, all of which are in Mission Architect:

  • Includes the updated RIC components for relative spacecraft position.  These show up in the optimizer and Graphical Analysis.
  • Includes the new launch trajectory estimation tool within the Set State event.
  • Includes the ability to optimize your "Set State" events directly from within the Mission Optimizer.  This includes in the Set State Directly (the old Set State stuff) and the new Launch Estimator parameters.
  • A handful of other very minor fixes/things.

One bad point: this pre-release is extremely hot off the press.  I think I've got everything more-or-less tested, but it would be great if people could take a look and see if it's doing anything noticeably stupid or wrong anywhere. I literally just wrote the optimizer stuff for the normal Set State parameters a few hours ago...

There will be one more feature pre-release before v1.5.7 drops officially.  The goal of that will be to introduce some new "landing" functionality that I've wanted to get into Mission Architect for some time.  These features are really twofold and include:

  • A new "Landing" event.  This is going to be fairly simplistic and just fix your spacecraft to the body frame of your central body, at whatever latitude, longitude, and altitude you call it at, for a user-specified period of time.  This is a good place to use the new "launch" stuff afterwards! :wink:
  • Two new graphical analysis tasks and optimizer constraints: vertical speed and horizontal speed.  These will be available for general use, but I'm envisioning using them mostly for setting up landing burns with the normal finite duration delta-v events. 

One question: would there be interest in me building a feature to display a translucent atmosphere sphere around the central body in the Mission Architect display window on the right if the user selects the option to do so?  Or would that be useless?  Let me know!

Anyways, what do you all think of all this? :)

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56 minutes ago, Arrowstar said:

Good news!  I have a new pre-release of 1.5.7 for people to play around with and take a look at.

Grabbed it. No time to test any of the new stuff (rrrgggh) but I can at least put it through my normal use for the moment and see if anything breaks

56 minutes ago, Arrowstar said:

One question: would there be interest in me building a feature to display a translucent atmosphere sphere around the central body in the Mission Architect display window on the right if the user selects the option to do so?  Or would that be useless?  Let me know!

As a visual aid for posting figures for other people to see, that'd be sweet. Practical use however... I don't think I would miss not having it. If it's something that's going to give you trouble to implement, I'd vote "don't bother".

1 hour ago, Arrowstar said:

Anyways, what do you all think of all this?

Awesome, as always

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16 minutes ago, Arrowstar said:

What event terminates at the start of that jump?

nothing, that's the problem. See included mission file - I just have a Coast to Pe event that should run all the way to the bottom of the curve

Also another issue: mission file w/log

Load the mission file and try to advance to the last state (Coast to Pe). Beeps at me and throws some errors in the log

 

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1 hour ago, Drew Kerman said:

nothing, that's the problem. See included mission file - I just have a Coast to Pe event that should run all the way to the bottom of the curve

Also another issue: mission file w/log

Load the mission file and try to advance to the last state (Coast to Pe). Beeps at me and throws some errors in the log

 

Can you check to make sure the mission file you gave me for the first problem is correct?  I don't see any issues when I look at  the plot.  What UT does the issue occur at (not MET)?

EDIT: Nevermind, I see it.  It's a data resolution thing.  The second point you have a data point at is the periapsis.  So the altitude is "jumping" because you're starting to swing around the planet and the graphing just doesn't have enough resolution there.  Add in more points per coast in Script -> Execution Settings if you need more resolution.

1 hour ago, Drew Kerman said:

Load the mission file and try to advance to the last state (Coast to Pe). Beeps at me and throws some errors in the log

 

I missed something when I created the pre-release.  This is a bug I'll fix very soon.  Thanks for pointing it out!
 

EDIT: Issue resolved for next release.

Edited by Arrowstar
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