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Arrowstar

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  1. Unfortunately this proved to be quite the pain in the neck. I don't think it'll be possible. You can always export the lat vs long from Graphical Analysis to see the 2D trajectory, of course. In MA's main display, the body does not rotate at all because there is not really a singular time to rotate it to. I've fixed the issue for mission animator, though. The central body will now rotate properly. I suppose. What's the use case here? I generally feel like the textured spheres are an improvement all around and there isn't much of a reason to go back to them.
  2. Hi everyone, Tonight I've built KSPTOT v1.6.8 pre-release 1. This pre-release introduces a major new feature to Launch Vehicle Designer, the geometry system. Please see my post above for details. Here's the full change log: LVD: The function to export a kOS CSV file has been updated to allow users to select the event(s) they want to export. LVD: Introduction of the geometry system. LVD: The "launch vehicle" menu is now called "scenario," and the "edit launch vehicle" menu beneath it is now called "edit vehicle configuration." Some additional bug fixes and perfor
  3. Here's a nice video showing what LVD's kOS script plus the new reference frame system can do. I have the vehicle pointing at KSC throughout an orbit, and during that time, we're trying to keep one face of the vehicle pointing at the Sun as closely as possible.
  4. Hi everyone, Tonight I'm pleased to be able to share with you all the next major feature coming to KSPTOT's Launch Vehicle Designer (LVD). Having previously improved the ability of LVD to handle different types of orbital elements, the next thing I wanted to do was allow users to create their own reference frames within which those elements could be used. This has led to the creation of the Geometry system within LVD. The geometry system has four main components: points, vectors, coordinate systems, and reference frames. Points are just that: 0-dimensional locations in space
  5. Ooooh. Okay, I see. I guess maybe I didn't understand the original request. I had been sort of under the impression you wanted me to implement the KWP model in KSPTOT, which is not really feasible lol. I'll see what I can do.
  6. You can certainly change the atmospheric inputs in the bodies.ini file for pressure and temperature. I think that's as far as this is going to go in KSPTOT. Managing the current atmospheric model is a pain in the neck already, and I would hate to try to add another one that's even more complex. I think one of the two tutorials that ships with KSPTOT does include some brief discussion of MFMS, even if it's for MA. But it's pretty simple to use in general, so I'd encourage you to play around with it and ask specific questions here if they come up.
  7. Hi everyone! This afternoon I'm pleased to announce the release of the KSP Trajectory Optimization Tool v1.6.7! This is a major release that generally adds significant new functionality to Launch Vehicle designer. It also fixes some bugs in Mission Architect and other parts of the application. One of the marquee improvements to Launch Vehicle Designer is the ability to export LVD steering and throttle controls to a CSV file which can be read in from a custom kOS script. You can check out some of the discussion on this topic earlier in this thread, or check out the following demons
  8. Look for Powered Explicit Guidance, PEG. A modified version of PEG was flown on Shuttle so it's pretty good all around.
  9. You're going to make me rewrite the KSPTOT atmosphere models again, aren't you?
  10. Well, it's not actually as bad as I was thinking it was going to be, but clearly it's fairly far off. This is why real rockets use closed loop guidance for orbit insertion and don't just run open loop steering the whole way to orbit. Would you mind sharing the updated script with me? If you've already done it and don't mind me just using it after the v1.6.7 release, I may just go that route...
  11. I noticed this too, yes. There's not much I can do about it, though. This is a control systems issue. kOS needs to be smart enough to find the short way rotation between its current and commanded attitude. At the moment, it's not. Maybe I'll file a bug report with the kOS devs. At least it'll get on their radar that way. Yes, that's true. It's not a bad suggestion actually. I don't think I'll change it for the v1.6.7 release since I really do want to get it out the door in the next few days, but I can look into the change afterwards. I suspect it wouldn't be hard at all
  12. Great idea, I'll do this for the release. So I thought about this and almost did it. However, with the ability to jump around in time and propagate backwards, it seemed like it would cause too much confusion to the user about which events to select. Outputting everything and then using the new "advance to event" functionality to later jump past completed events spares everyone that confusion at the expense of just a bit of loading time in kOS. The only big thing it impacts for most integrators is the number of data points output: the solutions themselves generally stay the sa
  13. Well that is interesting... so it looks like MATLAB's csvwrite function spits out data in scientific notation if the numbers get too long. Let me investigate how to do this properly. Thanks for sharing. I'll try to get a new build up ASAP. EDIT: By the way, just by looking at your CSV file, I see you may have an issue. You need to up your data rate so the linear interpolation in the script doesn't get to wonky. Try setting your global integration output step size to 1 second. You can do this in Settings -> Integration Settings. Then experiment to find a good balance between too
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