06:46 <_whitenotifier-1adf> [Principia] pleroy opened pull request #3590: Address comments from #3589 - https://github.com/mockingbirdnest/Principia/pull/3590

06:46 <_whitenotifier-1adf> [Principia] pleroy closed pull request #3590: Address comments from #3589 - https://github.com/mockingbirdnest/Principia/pull/3590

11:03 <queqiao-> ⟨EMPERORINTERNET⟩ the TWP dv numbers are a bit off with principia, or am i doing something wrong?

11:03 <queqiao-> ⟨EMPERORINTERNET⟩ i mean they are a couple hundred dv too cheap

11:04 <queqiao-> ⟨EMPERORINTERNET⟩ 3,5k in twp, usually 3,7-3,8k in praxis

11:05 <queqiao-> ⟨Starkid⟩ I think maybe TWP assumes keplerian orbits

11:06 <queqiao-> ⟨test_account⟩ i think it's mainly becaise non-instant departure burn

11:06 <queqiao-> ⟨test_account⟩ * becase of

11:06 <queqiao-> ⟨Marsh⟩ They're usually close but not exact. Make sure your maneuver frame is in the body you're orbiting (probably ECI) and your plotting frame is your destination

11:06 <queqiao-> ⟨test_account⟩ * because

11:07 <queqiao-> ⟨Starkid⟩ ⟪test_account⟫ i think it's mainly because of […] ⮪ In that case, are you using a Centaur for the burn?

11:08 <queqiao-> ⟨test_account⟩ i think it's mainly because of […] ⮪ also, if you are using inertially fixed burns, that adds some dV losses

11:09 <queqiao-> ⟨Starkid⟩ ⟪test_account⟫ also, if you are using inertially fixed […] ⮪ But TWP assumes instant burn so that should be irrelevant?

11:09 <queqiao-> ⟨test_account⟩ it's relevant because TWP assumes an instant burn and in reality it's not instant

11:10 <queqiao-> ⟨test_account⟩ * fact

11:10 <queqiao-> ⟨Gratak-⟩ Does it assume instant? I'd say it assumes some low burn time.

11:11 <queqiao-> ⟨Gratak-⟩ I seem to remember some edge cases where the dv of TWP was actually to high (I was accidentally planning with the leftover of the last orbital stage)

11:11 <queqiao-> ⟨test_account⟩ I think it's safe to assume that TWP just uses a dV figure that is applied instantly, without any burn time

11:11 <queqiao-> ⟨Starkid⟩ But if it assumes instant burn then inertially fixed vs prograde loses meaning?

11:11 <queqiao-> ⟨Gratak-⟩ * too

11:12 <queqiao-> ⟨Gratak-⟩ I'm totally unsure about the fixed inertia... For plane changes this is actually more effective, right?

11:12 <queqiao-> ⟨Starkid⟩ Because the vector of the burn doesn’t change throughout, it’s instant

11:12 <queqiao-> ⟨Starkid⟩ * over the duration, the duration is

11:12 <queqiao-> ⟨test_account⟩ ⟪Gratak-⟫ I'm totally unsure about the fixed […] ⮪ yes, in fact, it works better for GEO maneuver

11:12 <queqiao-> ⟨test_account⟩ but not for departure burns

11:12 <queqiao-> ⟨Gratak-⟩ Good to know

11:13 <queqiao-> ⟨Gratak-⟩ Never tried it for departure since it behaves very weird there anyway

11:13 <queqiao-> ⟨test_account⟩ i did because of weird reasons, not sure anyone else does it but mentioned just in case

11:13 <queqiao-> ⟨egg⟩ ⟪Starkid⟫ But if it assumes instant burn then […] ⮪ those are _Principia_ settings.

11:13 <queqiao-> ⟨egg⟩ it is TWP that assumes an instant burn, not Principia.

11:14 <queqiao-> ⟨EMPERORINTERNET⟩ what sometimes seems to work is plot a simple planetary transfer with mechjeb and copy over the numbers

11:15 <queqiao-> ⟨EMPERORINTERNET⟩ need to fiddle around a little, but it's very close

11:15 <queqiao-> ⟨Gratak-⟩ ⟪test_account⟫ i did because of weird reasons, not […] ⮪ Thanks for preventing me form wasting time trying to find out if it's more efficient 🤣

11:16 <queqiao-> ⟨Gratak-⟩ * from

11:17 <queqiao-> ⟨Gratak-⟩ ⟪EMPERORINTERNET⟫ what sometimes seems to work is plot a […] ⮪ Imho what helps is fiddling around with the dv until the numbers of days for the journey is right

11:17 <queqiao-> ⟨Gratak-⟩ * right. Never tried the mj maneuver

11:17 <queqiao-> ⟨Gratak-⟩ +though

11:21 <queqiao-> ⟨Marsh⟩ TWP is never perfect for me. If it's within 100 m/s I'm pretty happy. I always sim to confirm the burn on launch day

11:22 <queqiao-> ⟨Gratak-⟩ I find it very annoying to do that... The "sim ahead" feature is terrible to use... It takes a long time and then your fuel is gone and you have to wait for it to be refilled by the launch clamps...

11:22 <queqiao-> ⟨Gratak-⟩ * use (beyond short times)...

11:23 <queqiao-> ⟨Marsh⟩ You can just start in orbit in however many days advance you need to be at your launch day

11:23 <queqiao-> ⟨test_account⟩ and then the orbit will not be the correct parking orbit

11:24 <queqiao-> ⟨Marsh⟩ Hyper edit the lan and inclination

11:25 <queqiao-> ⟨test_account⟩ also boiloff kills the craft in orbit.

11:26 <queqiao-> ⟨Marsh⟩ It's already on launch day. Just plot and burn

11:27 <queqiao-> ⟨EMPERORINTERNET⟩ simulating ahead crashes my game 7/10 times

11:27 <queqiao-> ⟨test_account⟩ i've done it up to 250 days ahead, 100-150 days is fine, 200+ can crash

11:28 <queqiao-> ⟨Marsh⟩ TWP gets you in the ballpark, but I never trust it with my life. Always confirm with a sim (as all things should be)

11:28 <queqiao-> ⟨test_account⟩ Or just have dV margin

11:28 <queqiao-> ⟨Starkid⟩ Do missions really have margin?

11:29 <queqiao-> ⟨Marsh⟩ Yea I was gonna say, that's very sub optimal of you to say

11:29 <queqiao-> ⟨Gratak-⟩ ⟪Marsh⟫ It's already on launch day. Just plot […] ⮪ It is? It seems to me that simulate ahead places the craft and the warps without showing that

11:29 <queqiao-> ⟨Gratak-⟩ * then

11:29 <queqiao-> ⟨test_account⟩ at some point, 300m/s margin for the departure burn doesn't really matter anymore

11:29 <queqiao-> ⟨test_account⟩ there are some launches without margin, but most have some margin

11:30 <queqiao-> ⟨Marsh⟩ ⟪Gratak-⟫ It is? It seems to me that simulate […] ⮪ If so you can just refill the tanks with hyperedit

11:30 <queqiao-> ⟨Gratak-⟩ True. But with Principia that warp takes a long time....

11:30 <queqiao-> ⟨Gratak-⟩ At least beyond early game

11:30 <queqiao-> ⟨Marsh⟩ But how else would you sim a launch before building the rocket 🤷‍♂️

11:31 <queqiao-> ⟨Gratak-⟩ I usually just test that it burns through all stages. Trust TWP to be 90% correct and test the insertion stuff by placing it in the target orbit

11:32 <queqiao-> ⟨Gratak-⟩ I would love to have a better solution, but simulate ahead doesn't do that in a way I want to use it

11:32 <queqiao-> ⟨Marsh⟩ I do all up tests. RiS rules are that reverts and edits are not allowed, so it must work the first time. Only way to know is to do a full sim

11:33 <queqiao-> ⟨test_account⟩ I suppose in a race there is no other choice but to fully sim all the launches

11:33 <queqiao-> ⟨test_account⟩ A lot of things can go wrong even besides TWP 💀

11:33 <queqiao-> ⟨Starkid⟩ hyper editing into the target orbit seems fine tho

11:34 <queqiao-> ⟨Starkid⟩ but the warp is an issue

11:34 <queqiao-> ⟨Marsh⟩ Delete old craft and debris so warp is faster

11:34 <queqiao-> ⟨Gratak-⟩ Yeah. I see. I allow reverts except on engine failure for myself

11:34 <queqiao-> ⟨Starkid⟩ can’t you just look at the KAC alarm and start the sim that many days ahead?

11:34 <queqiao-> ⟨Gratak-⟩ We are going off topic though

11:35 <queqiao-> ⟨Gratak-⟩ Quick, post some cats somebody

11:35 <queqiao-> ⟨Marsh⟩ Are we? This is a principia discussion

11:45 <queqiao-> ⟨egg⟩ Precisely: the topic here is cats.

14:03 <paculino> Is this on-topic because it mentions both cats and Ea-nāṣir? https://xkcd.com/2758/

14:03 <queqiao-> ⟨egg⟩ yes.

15:08 <queqiao-> ⟨artificialselection⟩ is this the right view for an ECEF frame of reference?

15:09 <queqiao-> ⟨egg⟩ Yes.

15:09 <queqiao-> ⟨artificialselection⟩ ok cool

15:09 <queqiao-> ⟨artificialselection⟩ it was really throwing me off lmao