egg changed the topic of #principia to: Logs: https://esper.irclog.whitequark.org/principia | <scott_manley> anyone that doubts the wisdom of retrograde bop needs to get the hell out | https://xkcd.com/323/ | <egg> calculating the influence of lamont on Pluto is a bit silly…
<queqiao->
⟨night_beast⟩ so instead of one unstable orbit we're dealing with 2? sounds bad.
<queqiao->
There seems to be a few ways to deal with the problem, but none of them are good, just less worse than others 😢. It looks like with coms tech level 4 you can do the L4 + L2 option.
<queqiao->
In the end, here's what I think I'm going to do. I'm going to put a comm sat in L5. Then for any mission that requires landing on the back side, I'm going to put an antenna on my orbiter stage that can reach L5. As long as my orbiter says out of the black triangle, i should have something like 95% coverage of the moon's surface except when the orbiter is in front. I know the orbiter isn't a permanent solution, but it should last long enough for...
<queqiao->
... any single mission to the back side of the moon. (excuse the crude drawing)
<queqiao->
⟨night_beast⟩ wait... why is L5 not modeled in principia?
<queqiao->
⟨Al₂Me₆⟩ Not drawn explicitly != doesn't exist
<queqiao->
⟨egg⟩ The potential is very flat around the rim here, so that small perturbations make it quite hard to pick up the Lagrange points correctly, so we miss that one where trying to draw lines around the maxima. I should try to improve that.
<queqiao->
The dynamics are unaffected by this.
<queqiao->
⟨lpg4999⟩ is the number of lines drawn configurable? (and would increasing it make a difference for this?)
<queqiao->
⟨egg⟩ no. (and no, this is all crammed up at the top; the one line that is drawn that delineates L₄ is special-cased for that purposed.)
<queqiao->
⟨night_beast⟩ Yea, I also noticed L3 isn't modeled here either., although that one is easier to pinpoint where that would be.
<queqiao->
⟨night_beast⟩ * drawn
<queqiao->
⟨night_beast⟩ * either,
<queqiao->
⟨night_beast⟩ I'm guessing L4 is easier to get into anyway with a sling shot around the moon? or should you go around the back side of the moon for an L5 insertion?
<queqiao->
⟨Al₂Me₆⟩ ⟪egg⟫ no. (and no, this is all crammed up at […] ⮪ (I wonder how much work it would be to draw a heatmap instead and have the eyeballs do the optimization...)
<queqiao->
⟨Al₂Me₆⟩ +(And whether that would look good at all)
<queqiao->
⟨night_beast⟩ I'm looking at a graph like this one. But in-game the lines are probably physics based projections, and I think what egg is saying is that to have the lines drawn to the detail we would need for L4 & L5, the whole thing would just be one big blob of lines
<queqiao->
⟨egg⟩ ⟪Al₂Me₆⟫ (I wonder how much work it would be to […] ⮪ As far as dealing with the problem goes, you would have the same problem, this is very flat.
<queqiao->
As far as implementation goes, most of what we have done would not be reusable, so let’s not go there.
<queqiao->
⟨egg⟩ no. (and no, this is all crammed up at the top; the one line that is drawn that delineates L₄ is special-cased for that purpose.)
<queqiao->
⟨egg⟩ ⟪night_beast⟫ I'm looking at a graph like this one. […] ⮪ > the whole thing would just be one big blob of linesIt would, if the lines were drawn at equal intervals.
<queqiao->
The line you see enclosing L₄ is not at the same spacing from the rest as the other ones are from each other, it is drawn specifically to highlight L₄. We could try to be more clever and pick another line which would highlight L₅.
<queqiao->
⟨egg⟩ The plot you show looks like what you get for very similar masses (like the Pluto-Charon system); there things are not as flat.
<queqiao->
⟨night_beast⟩ So what's the best way to get into one of the L4/L5 points? Let me know if I'm on the right track.
<queqiao->
There's A, launch to the moon, make a trip around it and jet out on plane and just manage orbit sizes until you get an intersect with L4
<queqiao->
or B since they're offset 60 degrees from the moon, launch 4 hours early (for L5) or 4 hours late (for L4) , go straight there and circularize into the L4/L5 point
<queqiao->
⟨cxg2827⟩ is this expected accuracy with executing principia maneuver via mechjeb, or did i incorrectly set something? This is almost as accurate as my iriginal attempt at an unguided impactor
<queqiao->
⟨lpg4999⟩ depends on various factors, but it's not outlandish
<queqiao->
⟨lpg4999⟩ the point of a guided tli is being able to correct it
<queqiao->
⟨lpg4999⟩ "duration 2.7s" does seem to suggest an error
<queqiao->
⟨cxg2827⟩ ok, I guess I'll have to modify the stage to increase RCS propellant
<queqiao->
⟨night_beast⟩ Yea, I've never been off by more than 1/2 a moon's width before with my TLIs
<queqiao->
⟨cxg2827⟩ i might have clicked instant impulse now that you mention it
<queqiao->
⟨lpg4999⟩ (and so does needing so much normal dv)
<queqiao->
⟨lpg4999⟩ * binormal
<queqiao->
⟨lpg4999⟩ and if this is guided, using 'inertially fixed' would probably be another error
<queqiao->
⟨cxg2827⟩ i ve noticed in the few TLIs ive done and following a 3 day transfer in the planner tool, i have been consistently needing a good chunk of binormal with a tangent of 3150. here is a revert without instant impulse, still a bit off but slightly improved.
<queqiao->
⟨night_beast⟩ You need to plan a 4 day transfer if you don't want to have to add binormal... you should be using 4 day
<queqiao->
⟨cxg2827⟩ whoops, need to fix "inertially fixed"
<queqiao->
⟨egg⟩ The manœuvre frame should probably be ECI rather than MEO, too.
<queqiao->
⟨cxg2827⟩ Ok gotcha, I think from watching Nathankells playthroughs I caught him mentioning 3 days which is why i set the transfer to that
<queqiao->
⟨cxg2827⟩ though this is me changing the transfer setting without full context
<queqiao->
⟨lpg4999⟩ duration shouldn't have anything to do with needing or not binormal, but a short duration does necessarily mean needing more dv
<queqiao->
⟨cxg2827⟩ thanks all, this is more what i was hoping for
<queqiao->
⟨egg⟩ ⟪night_beast⟫ I can't get it stable 😦 ⮪ This doesn’t look too bad, but your plan length is far too short. I suspect this trajectory stays in the vicinity for a while.
<queqiao->
⟨night_beast⟩ ⟪egg⟫ This doesn’t look too bad, but your […] ⮪ but it's an L4/L5 point, so shouldn't it try to stay in the middle of that shelf?
<queqiao->
⟨egg⟩ it shouldn’t run away completely. But here we cannot see where it’s going, because the plan is very short; maybe it comes back.
<queqiao->
⟨night_beast⟩ Closer, but I feel it's still too large is it not?
<queqiao->
⟨night_beast⟩ What should my DV be to enter the point? I've checked everything from 800 to 3K DV and none of it makes sense
<queqiao->
⟨thunkii⟩ ⟪lpg4999⟫ duration shouldn't have anything to do […] ⮪ i think it does because you have to account for longer moon travel time cross-plane to launch orbit. unless you're launching in-plane of course.
<queqiao->
⟨thunkii⟩ ⟪night_beast⟫ What should my DV be to enter the […] ⮪ you probably want to match speeds with Luna, which is moving at 1000 m/s, and your apoapse velocity is going to be around 200 so yeah 800 makes sense
<queqiao->
⟨thunkii⟩ that sounds close enough for government work at least
_whitelogger has joined #principia
<queqiao->
⟨Gopnik_Boi⟩ Im downloading Principia for the first time and for some reason it says "Principia.DLL failed to validate or wasn't found" but it is in my files so help?
<queqiao->
⟨egg⟩ > it saysWhat does « it » mean here?
<queqiao->
⟨Gopnik_Boi⟩ i get like a messege in ksp menu
<queqiao->
⟨Gopnik_Boi⟩ its like when teakscale sends a warning
<queqiao->
⟨egg⟩ ⟪Gopnik_Boi⟫ i get like a messege in ksp menu ⮪ Is what you quoted the exact wording of the message?
<queqiao->
⟨Gopnik_Boi⟩ more or less
<queqiao->
⟨Gopnik_Boi⟩ want screenshot
<queqiao->
⟨egg⟩ Yes.
<queqiao->
⟨Gopnik_Boi⟩ k wait a sec
<queqiao->
⟨Gopnik_Boi⟩ You are trying to execute the source code of Principia instead the binary.
<queqiao->
⟨Gopnik_Boi⟩ The Principia DLL failed to load.
<queqiao->
The principia DLL was not found at 'GameData\Principia\x64\principia.dll' in directory 'D:\SteamLibrary\steamapps\common\Kerbal Space Program'.
<queqiao->
Warning: don't load a Principia save before you have fixed this error; it might get damaged.
<queqiao->
⟨Gopnik_Boi⟩ and this
<queqiao->
⟨egg⟩ ⟪Gopnik_Boi⟫ You are trying to execute the source […] ⮪ Have you tried doing what the error message says?
<queqiao->
⟨Gopnik_Boi⟩ kinda i installed the newest version of principia
<queqiao->
⟨egg⟩ No you did not.
<queqiao->
⟨Gopnik_Boi⟩ the thing with arabic letters
<queqiao->
⟨egg⟩ You downloaded the source code, not the actual release.
<queqiao->
⟨Gopnik_Boi⟩ ohh and where is the reales
<queqiao->
⟨Gopnik_Boi⟩ idk why its called gamedata
<queqiao->
⟨egg⟩ Alright. delete both of these.
<queqiao->
⟨Gopnik_Boi⟩ ok
<queqiao->
⟨egg⟩ Now, go to the readme https://github.com/mockingbirdnest/Principia#readme, and click the link that says "Download it here for 1.8.1, 1.9.1, 1.10.1, 1.11.0, 1.11.1, 1.11.2, and 1.12.2 to 1.12.5.".
<queqiao->
⟨egg⟩ You will get a zip. Inside that zip is a folder called GameData. You must _merge_ this folder with your Principia install’s GameData, not put it under it. That is, when you are done, you should have <KSP directory>\GameData\Principia.
<queqiao->
⟨Gopnik_Boi⟩ i think i did it lemme start ksp
<queqiao->
⟨Damien⟩ ⟪egg⟫ Alright. delete both of these. ⮪ Inb4 he deleted his entire gamedata
<queqiao->
⟨egg⟩ You will get a zip. Inside that zip is a folder called GameData. You must _merge_ this folder with your KSP install’s GameData, not put it under it. That is, when you are done, you should have <KSP directory>\GameData\Principia.
<queqiao->
⟨Gopnik_Boi⟩ nuh uh
<queqiao->
⟨Gopnik_Boi⟩ btw wgg i did it wrong but have math lesson now thanks for helping
<queqiao->
⟨Gopnik_Boi⟩ was i supposed to delet this
<queqiao->
⟨nazfib⟩ Yes.
<queqiao->
⟨Gopnik_Boi⟩ The Principia DLL failed to load. The […] ⮪ i still get this
<queqiao->
⟨nazfib⟩ So, you downloaded the .zip file from the Google Drive link, unzipped it, then placed the _contents_ of the GameData folder of the .zip file in the GameData folder of your KSP install? And there's no GameData folder _inside_ your GameData folder? And you're not using any weird workarounds to by-pass the PD launcher?
<queqiao->
⟨Gopnik_Boi⟩ i have the normal game data
<queqiao->
⟨egg⟩ But as the hovertext indicates, _you have a GameData inside GameData_.
<queqiao->
⟨egg⟩ You should not.
<queqiao->
⟨egg⟩ I told you twenty minutes ago to delete the GameData inside GameData.
<queqiao->
⟨Gopnik_Boi⟩ i did thew link if i downlaod it it comes upp as gamedata
<queqiao->
⟨Gopnik_Boi⟩ * the
<queqiao->
⟨egg⟩ You will get a zip. Inside that zip is […] ⮪ Please read this message again, in its entirety, and only proceed once you understand everything it says.
<queqiao->
⟨Gopnik_Boi⟩ ok ill continu this in like 50 mins
<queqiao->
⟨fiora⟩ i executed a maneuver precisely with mechjeb but ended up with a trajectory over 4 million km off. i didn't run out of fuel, and my RCS kept me pointed the right way the whole time. what could be going wrong? according to a quick attempt at using principia to create a correction node, i'd need ~300m/s (!) to correct the trajectory.
<queqiao->
⟨fiora⟩ i executed a maneuver precisely with mechjeb but ended up with a trajectory over 4 million km off. i didn't run out of fuel during the burn, and my RCS kept me pointed the right way the whole time. what could be going wrong? according to a quick attempt at using principia to create a correction node, i'd need ~300m/s (!) to correct the trajectory.
raptop has quit [Ping timeout: 189 seconds]
raptop has joined #principia
<queqiao->
⟨egg⟩ fiora what happend to your flight plan eggsecution problems?
<queqiao->
⟨fiora⟩ I realized I had forgotten to rebase immediately before the actual execution
<queqiao->
⟨egg⟩ ah, and boiloff or some other change of mass messed things up?
<queqiao->
⟨fiora⟩ I think it might have been RCS or a mistiming. not sure
<queqiao->
⟨fiora⟩ +maneuvers
<queqiao->
⟨fiora⟩ could also be boiloff? either way a good note. always rebase like 3 minutes before the execution and then correct