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Arrowstar

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  1. Arrowstar
    1) Was probably an oversight. I'll take a look tomorrow if I can. 2) Thanks for breaking things lol. You are on the latest pre-release, right? I'll see if I can't figure out what's going with the bugs tomorrow.
  2. Arrowstar
    Okay thanks for that tidbit of information. I guess what I'm still hoping to find is the actual math that KSP uses to compute reentry heating. The link I showed has a relationship but it's a mere proportionality, implying that there's some constant out there that I would need to get an actual value. Any idea what that constant is?
  3. Arrowstar
    Digging around some more, @NathanKell, it looks like you've done some work in re-entry modeling in KSP. Do you have any insight into the actual models used by KSP itself to model aerodynamic heating rate?
  4. Arrowstar
    I'll post this here for more visibility in case anyone has an answer to how aerodynamic heating works in KSP...
  5. Arrowstar
    Hi all, Does anyone know how KSP computes aerodynamic heating on vehicles in the atmosphere of a body? I've found some basic relationships on aerodynamic heating in this chart package (slides 17-19), but I'd like to find out what KSP does and uses. Does anyone have any insight? Thanks!
  6. Arrowstar
    Hi everyone, Tonight I compiled the 3rd pre-release of KSPTOT v1.6.3. This is primarily a bug fix release for LVD. Here is the change log: Added a new C3 constraint to MA and LVD; Fixed plotting children bodies around Sun (or top level solar system body); Fixed title of Set Stage State UI; Fixed issues with deleting variables improperly; Fixed issue with thrust being reported incorrectly if throttle is > 0 but all connected tanks to an engine are empty. Now reports zero for that engine as expected; Fixed issue when trying to create an Add Mass to Tank action; Added ability to activate/deactivate constraints without deleting them; Activating hold down now kills all surface-relative velocity; Resolved issue with executing script starting at an event not first. Re-enabled for optimization only; The plot working label is now drawn quicker when you do something that requires it to be made visible; Added undo/redo states to most of the integrator/optimization option menu callbacks. Please let me know if you find any bugs or have any issues. Oh! This is probably a good time to share that I am working on a tutorial for Launch Vehicle Designer. Entitled "Eve: The Final Frontier" (cheesy, yes, I know), this tutorial walks users through modeling a sample return mission to Eve. All phases of flight, from ascent, interplanetary cruise, and entry/descent/landing are modeled. Use of this pre-release or later will be required. I'm looking forward to sharing with you all. Thanks and happy orbiting!
  7. Arrowstar
    I don't think @PLAD has been around for almost a year, sadly.
  8. Arrowstar
    Can I see some screenshots (and the MAT file from MA if that's what you're using)?
  9. Arrowstar
    This issue is resolved in the latest pre-release actually. Give it a try and see if it helps any. Glad it otherwise is working well!
  10. Arrowstar
    So there are a few things that can cause the optimization to take a long time. First, if you have many variables, the optimizer needs to compute the gradient for each of them. This can cause individual iterations to take a significant amount of time. Second, it may just be difficult (or impossible) to find parameter values that achieve what you want. The optimizer is good but it can't break physics. If you find that you are having trouble hitting targets, then consider adding more DV maneuvers, expanding the bounds on variables you already have, and giving the optimizer a better "initial guess" to start from. If you'd like, you can upload a copy of the MAT file that the Mission Architect mission data is stored in and I can take a look and see if I can't help things any. This is fine, yes. After you create the video, you are welcome to send me a link and I'll put it up on the first post of this thread. And yes, a link to this thread and the Ko-Fi "buy me a coffee" page would be much appreciated wherever you post the video! I certainly appreciate that sort of support. Thank you. Thanks for the input, @Drew Kerman!
  11. Arrowstar
    Can you take a screenshot the Multi-Flyby Maneuver Sequencer (MFMS) user interface as it was right before you tried to do the optimization? I'd like to try to replicate it. MFMS should never take that long. Once you get your mission set up, you can try to create the mission plan in Mission Architect, and then use that information to execute all the maneuvers within KSP itself. There are a few tutorials that come with KSPTOT that explain how to go from very basic information to Mission Architect. Let me know if you have any more questions!
  12. Arrowstar
    No, unfortunately this is not possible at this time. What analysis are you running that takes a long time?
  13. Arrowstar
    Hi there! Yes, there is a feature to do this. It's called either the Multi-Flyby Maneuver Sequencer (MFMS) if you want to optimize a particular trajectory, or the Multi-Flyby porkchop plot (or something to that effect) if you want to search over a large span of time. The latter will actually plot "windows" so I suspect that's what you're after. You can use the MFMS later to refine down a good trajectory if you desire. Just a heads up, the run time on this multi-flyby porkchop plotter can get lengthy if you have many legs (because it has to compute every permutation), so start simple and work your way up as you learn to use it. And definitely let me know if you have any questions or you find any bugs while you use it. Happy orbiting! And nice work on the mission too.
  14. Arrowstar
    Hey everyone, Tonight I built KSPTOT v1.6.3 pre-release 2. This is a minor build that includes mostly bug fixes: Fixed an issue on Linux with the Help->About dialog box Fixed an issue with the vectorized Lambert solver that could occasionally arise when the solver was used with multiple inputs. MA: Added a DV magnitude readout to the Insert Delta-V Maneuver dialog box. Please let me know if you have any questions. Thanks!
  15. Arrowstar
    Glad you like it! Yes, I figure it's been a few thousand hours since 2013 or so, but its totally worth it. It's a great hobby. Let me know if you have any questions!
  16. Arrowstar
    RAAN is "right ascension of the ascending node". For the purposes of KSP, it is a synonym for longitude of ascending node (LAN). I'm sue you can find RAAN/LAN in both KER and MJ, yes.
  17. Arrowstar
    No worries, thanks for letting me know.
  18. Arrowstar
    I'm glad you were able to find a solution. I'm not sure what happened honestly. Do you know why you needed to delete that directory to restart the application?
  19. Arrowstar
    @1greywind: I added the dv magnitude text to the MA Insert DV Maneuver dialog box like we talked about. It will be in the next pre-release.
  20. Arrowstar
    Memory usage is probably about 1-2 GB, but generally on the lower end of that scale unless you have some big analysis running. CPU usage will always be at least 1 core's worth when you're running something, but could potentially go up to 100% if you're using parallel optimization in Mission Architect or Launch Vehicle Designer, or some of the other applications which have implicit multithreading (Porkchop plot, Multi Flyby Maneuver Sequencer). Note that CPU usage when the application is idle will always be nearly 0%.
  21. Arrowstar
    If you have any questions, please don't hesitate to post here and let me know so I can help out. :)
  22. Arrowstar
    Hi everyone! Today I'm releasing the first pre-release of KSPTOT v1.6.3. This pre-release has a number of new features that are mostly but not exclusively around LVD. There's lots of good stuff in here. Let's take a look at the change log: LVD: Initial implementation of 3rd body gravity force models. (There may be some bugs here so please report if you find anything.) LVD: The initial state body fixed coordinate system now uses azimuth, elevation, and magnitude for the velocity components. LVD: New initial state coordinate system type: "Circular Restricted 3 Body Problem" (CR3BP) LVD: Plot type can be changed from 3D inertial to 3D body-fixed and 2D. See new "View" menu. LVD and MA: The "observe optimization" UI (that shows the optimization progress) now has a tooltip that shows the variable name and value when you mouse over the bar graph. I also enabled the data tips so you can select the data points in the objective function progress plot and the maximum constraint violation plot. Rendezvous Maneuver Sequencer (RMS): Can now only optimize the first of the two DV maneuvers. Useful for computing intercepts where you don't intend to stop at your target. RMS: Improvements to the plotting for hyperbolic orbits. Other minor performance enhancements in LVD. Bug fixes application-wide. Both Windows and Linux builds are available here. Please let me know if you have any questions. Thanks and happy orbiting!
  23. Arrowstar
    Hey there! In Mission Architect, drag is only important for aerobraking, so that's where you set drag. In Launch Vehicle Designer, the "Edit Drag Properties" area of the initial state is one place where you can edit those parameters. However, events can have actions that modify drag parameters. You can add a "Set Drag Properties" action to do this. In the future, you are welcome to please post KSPTOT questions over in the KSPTOT thread. Thanks!
  24. Arrowstar
    Unfortunately this is impossible. Between the UI and the backend code, KSPTOT is nearly 100k lines of code. A rewrite just to go to another language with no additional benefits would take years of no added value.
  25. Arrowstar
    Hi everyone, I found a somewhat important bug in the latest release of KSPTOT. Within Launch Vehicle Designer, if you don't have any tank to tank connections or engine to tank connections, and you try to set the initial stage states of the vehicle from the Initial State menu dialog box, you will get an error. I've hotfixed the release from yesterday with a patch and re-uploaded. If you downloaded v1.6.2 between last night and now, please re-download to avoid this bug. Thanks!
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