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I like to deorbit my debris using a craft that has an AGU attached. A few versions back, I had no issues with this. But now targeting debris targets the root part of the debris, not the COM, and once the klaw is attached, I can't target the COM, like I can when attached to an asteroid. Am I missing something? Or is there a workaround? I'd gladly install (or even write, if I knew where to start) a plugin that adds the "target COM" ability to the right click menu, or changes the game's targeting behaviour to target vessels' COM by default, or treats debris as a singular part that forces COM to be targeted. Does anyone have suggestions for this issue?

I was away from KSP for a while, but since I've been back, I've come to find that one can no longer target the COM of a piece of debris once latched on to it with the AGU. I seem to remember being able to do this back in the day, just as I can today with asteroids. This seems so backwards, as it's the engineered object whose COM should be able to be known, while an asteroid's should be less certain. I've considered options like a "pull design" tug that could perhaps work, but I'd still need to know roughly where the COM is at the time of attachment, so that's not my ideal. Also, I just feel like I should be able to know the COM of an engineered object (even if the engineers were kerbals). I'm open to other ideas and suggestions, but at this point I'm wondering what would be involved in writing a plugin that revives this capability. I imagine the devs had a reason for removing it, so maybe there is some big barrier to success here, but it seems like it might be worth a try... I've written up contract packs and waypoint collections in the past, and have a bit of "backend" experience, so something (seemingly) simple like this seems like it would be within my capacities. I'm just not too sure where to begin. Any help would be appreciated!

Can someone help shed some light for me? I thought I knew SCANsat... but then I found this, and I honestly don't get it. There is so much data here, and all the people responding are so excited about it... and I don't understand what the data means or why it pleases people or how it could be useful to me as a SCANsat user. I know that different scanner parts have different ideal orbit altitudes, and that small adjustments to that altitude will make for more complete scans of the surface, but this... this is something more, no? I think of myself as fairly well versed in KSP and its mechanics (orbital mechanics and game mechanics), but the significance of these graphs continues to elude me. I know some have to do with other mods that I don't use (KSPI, MKS, Karbonite, EPL), but what about the base SCANsat stuff? For example, what are the "Ideal Zones" graphs about? I don't think I know how to even read them properly, let alone what they describe. And what the heck is a resonance structure? (And Sidelaps?) And why was it not important to @technogeeky to include the data pertaining to the Kerbin system? Or did he, and I just missed it? Any help with understanding all this will be much appreciated.

I thought I knew SCANsat... but then I found this, and I honestly don't get it. There is so much data here, and all the people responding are so excited about it... and I don't understand what the data means or why it pleases people or how it could be useful to me. I know that different scanner parts have different ideal orbit altitudes, and that small adjustments to that altitude will make for more complete scans of the surface, but this... this is something more, no? I think of myself as fairly well versed in KSP and its mechanics (orbital mechanics and game mechanics), but the significance of these graphs continues to elude me. I know some have to do with other mods that I don't use (KSPI, MKS, Karbonite, EPL), but what about the base SCANsat stuff? For example, what are the "Ideal Zones" graphs about? I don't think I know how to even read them properly, let alone what they describe. And what the heck is a resonance structure? (And Sidelaps?) And why was it not important to the author to include the data pertaining to the Kerbin system? Or did he, and I just missed it? Any help with understanding all this will be much appreciated.

Nice! Thanks! I managed to make it work. I ended up leaving the initial value for the minimum distance unspecified. When I use the code below, the true anomalies spit out at the end were 0 (or whatever value I passed in that initial value array). I couldn't figure out why, as that didn't happen with the max distance array reduction. const res = distances.reduce((a, b) => a[0] < b[0] ? a : b, [a1 + a2, 0, 0]); But it worked without that initial value... just thought that was a bit strange. Anyway, thanks so much for your guidance! You've really helped me tie a nice bow on this

I'm sorry to necro this. I thought you might be interested in knowing that I did get to the bottom of this issue some months ago, but haven't done much with the results yet. I'm starting to work on it again... I find myself with more free time lately... Turns out the problem was a silly calculation error on my end, and both your code and my model in fact were returning identical results (long story short, I was conflating true anomaly and eccentric anomaly). More as an exercise and diversion than anything else, I am now wondering: What would I need to change about the original code to use it to find the absolute minimum distances between two orbits? If I understand correctly, the golden section search you employed is a twist on a method to find local minima. If I could "untwist" it (whatever that might mean), could I employ it in just that fashion? I'm working on trying to reverse engineer it, but my limited background isn't getting me very far very fast. Figured I'd go to the source

So I've been away from KSP for about 3 years. I've always missed playing it, but I fell away and got caught up in other projects. Last time I played was in 1.2. KSP2 hadn't yet been announced and Making History and Breaking Ground were but glimmers in the devs' eyes. I was good enough at the game to feel comfortable with landing on Mun and Minmus, rendezvous and docking, I had several mods installed and had played around with planes and VTOLs a bit. I had probably a couple hundred hours docked, but I never got around to leaving the Kerbin SOI... Though I was on the brink of such a mission before I put the game down back in 2016.I was watching a lot of Scott Manley videos to prepare Now I have some time and I'm looking forward to getting back into it in the new year, but I feel like I'm starting from scratch. So I figured before I jump back in, I'd ask the ol' community for a primer. Any pointers, advice, suggestions, guidance, recommendations, resources are welcome! Here are some prompts in the form of things I'm curious about: What new stock features are there? What still sucks in stock? In 1.2, aero forces and wheels were the achilles heel of the game. At least there was the Far mod for the former... ARE WHEELS FIXED?? Which major mods have been deprecated or abandoned, and what awesome new ones have come out? Is spacedock still the go-to repository? Is the community still as active as it was 3 years ago? Are people excited about KSP2? Is KSP still under active development, or has that slowed/stopped to work on the sequel? Who's who in the community these days? I think I've seen that Manley is still active as a YouTuber... who are some others to look out for as I take aim at the rest of the solar system?

@K^2 Whelp, I'm out of ideas at this point. I've learned enough about rotation matrices in the last few days to understand how to reproduce your transformX and transformY functions. I was hoping to find some minor discrepancy that, when resolved, would close the gap between the results. And the rotation matrices I came up with did differ slightly from yours, by a negative sign in the variable z for each. Changing it didn't make any difference at all. I checked the rotation matrix against the orbits' orientations in my model, and they are visually identical. As for bignumbers, I don't see how I could apply it in a way that would make any difference at all. I haven't tried it, because honestly I'm not sure where I would. I've played around with the degree of accuracy in your code, pushing it to the limit of crashing the browser page. No luck there, either. Would a more powerful machine even help, or will the browser always be the bottleneck? I don't understand why my model and your code agree on the max separation, but disagree on true anomaly. I'll keep thinking on it, but I'm definitely open to more ideas if you've got 'em. Maybe I'm missing something in the max2d or golden function... Again, I'll keep exploring.

@K^2Really, just enough to work out what's causing that 0.05 rad discrepancy. I'm happy to research and learn, but it can be hard to know where to look, and my formal mathematics training ended with high school calculus. These are definitely well out of my league. Thank you for the resource, though. Who knows, I may end up to coming back to them. This helped a lot, and I'm going to try to find more stuff like this. Just about the only thing left in your JS that I don't understand is the transformX and transformY functions, and I'm hoping that with that last puzzle piece I can close the book on this.

@K^2 Thank you SO MUCH for what you've done here. You've single-handedly brought me to within a hair's breadth of the solution to this problem that has been bugging me for months! I say "within a hair's breadth" because, oddly, when I put the true anomalies output by your algorithm into my model, I get a distance of 113191.131383 Mm, a difference of 169.675468 Mm from your algorithm's output (113360.806852). But, when I play around with fine adjustments to those body positions in my model, I can maximize the distance calculated in the model to within <10m of the algorithm output! So I just need to figure out why the true anomalies I'm finding are around 0.05 rad off from yours. I really believe my model is accurate... but perhaps more checks on that are in order. Whether the issue lies with my model or your code, I will continue looking into this and keep you updated. I'm sorry I needed so much hand holding on this... it's that I don't have a good grasp on the math used to transform the ellipses from 2D into 3D. Any resources you could recommend for me to read/watch to deepen that skill set?

@K^2 This gives a max separation a few Gm less than what I've been able to find just through trial and error.

@K^2That does look more believable. Seems likely I'm having issues on my end. Not sure why, though. I will also continue looking. One thing I do notice (and this could help explain our discrepancies), is that on the graph you provided, it looks like Dres' periapsis lies on the positive y-axis, and Jool's orbit swings away from it to the upper left. When I look at my model (and indeed at the map screen in KSP) in that orientation, Jool's orbit swings away from Dres' to the upper right when looking straight down at it.

Sure can! Jool SMA: 68773.56032 e: 0.05 Inc: 0.022759093795546 LAN: 0.907571211037052 APe: 0 Dres SMA: 40839.348203 e: 0.145 Inc: 0.0872664625997166 LAN: 4.88692190558413 APe: 1.57079632679490 Thanks so much for all your help! This is amazing.

@K^2 That's fantastic. Thanks for clarifying. I see it now. Thing is... something's not adding up. I've made this model (linked in my signature) against which I'm checking the angles and distances this script is spitting out. I've been using Dres and Jool... and I'm getting a max distance that I can't seem to replicate no matter how hard I try (off by 3Gm!). Plus, the angles are just plain nonsensical. I don't know what is leading to the inconsistencies. I'm trying to get it to add up, but no luck yet. If you get a chance to look at what I'm talking about, I'd be interested to hear your thoughts on a diagnosis. Here's what I've done with the code you provided. I'll warn you: it's not pretty; I'm not good enough at this to make it streamlined.

My cup overflows! Thank you! I will try this out tonight. Am I correct in my understanding that the centre of the ellipse (and not one of the foci) is at the origin?

This. Is. Incredible! You're my hero! Thank you! Purely for curiosity's sake, do you think there would be a relatively simple way to determine the points the two bodies would have to be at in their orbits to achieve their max separation? Looking at your code, I see a position function devoted to "3D Position at true anomaly T." That looks like the ticket! I'm having a hard time getting that value onto the browser page, though. I think it's because I haven't looked at JS in some time and am not at all familiar with the arrow function... what do I need to do here?

That would be incredible! I'm very much a beginner with code, but do have some limited experience with javascript, ruby, and (to an even lesser extent) python. If any of those work for you, I'd be "over the moon" just to have something to work from. I will say, though, that I'd need some clear commenting. All the internets to you for such a favor!

I'm looking for some help/guidance on what is turning out to be a surprisingly challenging math problem: I'm trying to find the maximum possible separation between any two given planets. I think it would be useful, or at least interesting, to know this kind of thing when constructing comms relay networks, etc. I've got some idea how to proceed, but my efforts keep coming up dry (not least because of my merely intermediate math knowledge). Seems my problem needs new eyes and new ideas. I'm all ears!

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I got one showing here: But I thought you had already seen that... I don't mind playing around a bit more with the math, but I can't promise results or give you much of an idea of when I'll get to do that, so I'd definitely encourage you to dig into it yourself. I'd like to help here, though. I'll do what I can!

Hi Drew, I take it you mean ecc>1? The problem is not how to constrain the conic. It's how to represent the asteroid's position on that conic. For the closed ellipses of all the planets and moons, the orbiting body is represented by a point that is mathematically tied to that path. Not so easy with the open hyperbola. KSP must have a way of doing it, though...

I've been futzing around a bit with your idea this week and I think I've got the beginnings of something you might be able to work with here. All I've added is some numbers and formulas in column S of the spreadsheet. One tricky thing with representing a hyperbolic orbit on a 3d plot is that we only want to see one of the branches (here, the one swinging by Kerbin). So right away the more obvious choices for commands to use in geogebra are ruled out: Hyperbola command, Conic command. So that leaves me with the Curve command, which uses parametric equations to plot a curve in a given range. I have not yet been able to figure out how to parameterise a hyperbola in 3 dimensions, so I tried plotting one in 2D that had your example's SMA and Ecc, and then tried to rotate that curve to the proper 3D orientation. I doubt I've managed to get it right on my first go. Take a look and tell me how it compares to your example. I can't test in KSP just now. It would be more computationally efficient if we could represent the hyperbola in 3D right out of the gate, so that's another challenge. It will be up to you to define a range for the curve (given in cell S23) that you think is appropriate. But once you've done that, how do you define the asteroid's actual position on that arbitrarily sized curve? Perhaps it would be better, in the case of hyperbolic trajectories, to represent the trajectory shape and the asteroid position independently, as opposed to interwining them as I did for elliptical orbits. But we have the beginning of something here.

Hey Drew. I have not abandoned this! I have not done any updates but have been using it myself for a project of my own. Point is, it's very much on my radar. As for hyperbolic trajectories, it's secondary to my interests but perhaps I could look into it when my own project gets wrapped up. What kind of functionality are you looking for specifically?

This should be do-able, but there's a chance the model will take a performance hit. I think what you need is a parameteically defined curve (google parametric equation for details). When I tried using them in my model, they made GeoGebra hurt. But I was trying to do all sorts of funny stuff with them. Ideally, I'd try to go with something else, but I'm not sure what that would be off the top of my head. I feel your pain. I did algebra in high school but nothing really beyond that. Google was a very good friend to me through this process. I would love to help you, but it will be at least a few weeks before I can really sit down with this and try to work it out. I'm in the midst of a renovation and a move. Next chance I get I'll take a look and let you know what I come up with, but I encourage you to keep at it in the mean time. Keep posting updates and asking questions I love that I'm not the only one getting use out of this, and I quite like sharing what I've learned while making it.