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  1. I've recreated the bug and I believe I've got it figured out. I reuploaded the PR7 ZIP file. Please go ahead and redownload that and let me know if you have any issues going forward. Thanks!
  2. Today I've built KSPTOT v1.6.10 pre-release 7. This pre-release adds a bunch of new functionality and includes some bug fixes and minor performance improvements, all of which are in LVD. Here's the change log: Noticeable performance improvement when using numerically propagated celestial bodies. LVD: Added new ground track tab to main LVD UI's display area. LVD: Added sky box code for more "cinematic" display of 3D trajectories. Set option to enable in View Settings. LVD: Added additional camera controls functionality (Dolly horizontally/vertically camera). LVD: New steering model: tabular quaternion interpolation. LVD: New throttle model: tabular throttle interpolation. LVD: Update version of IPOPT optimizer to v1.1.6. LVD: Add new SQP optimizer algorithm. LVD: Bug fixes and performance improvements. Please let me know if you find any bugs. Thanks! Happy orbiting!
  3. No, this is a new one certainly. Can't say I've seen this before. I'm going to push a PR7 out pretty soon (maybe even tomorrow), so can you let me know if the issue persists with the new build? If it does, I'll investigate further. Thanks!
  4. Ah, I didn't realize you were using Principia. In that case, yes, you can turn on the n-body calculations for the celestial bodies as you had it. Just realize that it's going to be very slow. Sorry about that.
  5. Ah, no, sorry, I think I see the confusion. Numerically propagating the orbits of the celestial bodies is NOT the same as using n-body gravity on your spacecraft. To enable n-body gravity, you need to do the following: In your initial state, set the bodies you want to use for 3rd body gravity. For each event, set the Force Model to use 3rd body gravity. That should be all you need!
  6. Honestly, just leave the numerical propagation to two body for everything. Your simulations will run much faster. You typically want to scale your objective function so that the value is between -1 and 1. Since final vehicle mass is the objective function, and the final vehicle mass is around 4, a scale factor of 10 is appropriate since it'll make it 0.4, which is between -1 and 1.
  7. You had a couple of issues that I was able to resolve: 1) You had numerical propagation turned on for all your celestial bodies. That's much slower than the two-body analytic solutions and was causing the propagator to take forever. I had to change things back to analytic two body propagation. 2) I scaled the constraints by their current value (Optimization menu -> Scale Constraints -> Current Value). 3) I scaled the objective function by 10. Once I did all of these, the optimizer brought the solution in easier and quickly. Here's the file. Please let me know if you have any questions with anything I did! Happy orbiting! https://drive.google.com/file/d/1t9DxXgP46S7R3gHbPCPeSpExvdcHQHFy/view?usp=sharing
  8. I have access but when I try to load your MAT file I'm told that it's not a binary MAT file. Can you try again? EDIT: Nevermind, seems like it works now.
  9. It can, but I'd still highly recommend using LVD. Did you try scaling the constraints as the text box message that pops up describes? Can you share your MFMS output with me so I can take a look at it and see what's going on? In other news, work on the new optional sky box functionality for LVD is progressing nicely. No more grey axes boxes if you don't want them!
  10. I've been working on a new display for Launch Vehicle Designer (LVD). This is a new ground track display that can show the following on a 2D map of a celestial body. This display is located on a new tab in the Display area of the main LVD GUI. Vehicle trajectory Ground object location and trajectory Celestial body location and trajectory Terminator line between lit and shadow (day and night) portions of the celestial body Terrain contours (may be turned off and off in View Settings) Here's a great image of Duna that illustrates these new functionalities. You'll also notice that the tool tips on this display are much richer and show more useful data. This is true for the 3D orbit display as well! This will show up in the next v1.6.10 pre-release. Let me know what you think! Happy orbiting.
  11. Hi everyone, I'm happy to announce that after a fairly lengthy hiatus, I've built KSPTOT v1.6.10 pre-release 6. This new build moves KSPTOT to a new MATLAB version, MATLAB R2023b. You will need to download and install the MATLAB Compiler Runtime version for R2023b to run this build. Please do so before attempting to run KSPTOT v1.6.10 PR6. Here's the change log: New MATLAB Version: R2023b LVD: Update NOMAD solver to v4.4 and removed v4.3.1. LVD: Enabled DiscoMADS option for NOMAD solver. MA/LVD: Updated the optimization variable plot mouseover label background color to be not transparent. LVD: Run Case Matrix workers now record diary as they run to a "running" log file. LVD: Updated tab order for initial state and set kinematic state UIs. LVD: New example: lvdExample_MunarFreeReturn MA/LVD: Many bug fixes. Please let me know if you find any issues. Thank you and happy orbiting!
  12. Just a heads up to everyone, the next pre-release will probably update MATLAB to R2023b (the latest version). It'll also have an updated version of the NOMAD optimizer (v4.4) in LVD, along with some other changes.
  13. I actually couldn't reproduce this error. Does it still happen for you? Propagating to certain "events", like true anomaly or whatnot, doesn't work as well in the integrator based system that LVD uses. This is why everything is time based. Set up constraints to the target you want at the end of an event and then optimize the propagation time of that event to meet those constraints. This should work out pretty well most of the time.
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