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Burninate

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  1. The question was intended to be: If you have to raise apoapsis substantially (but keep periapsis low), *and* do an inclination change, which to do first? And secondarily, how does that answer decay as plane ascending/descending points move away from the apo/periapses?
  2. Optimizing for minimum fuel expenditure: You are in a 4AU x 6AU eccentric orbit, inclined 10 degrees off from the ecliptic plane. The plane conjunction is very close to periapsis and apoapsis. You want to make an encounter with an atmosphere-possessing object in a 10AU circular orbit on the ecliptic. You have the forecasting power and patience to have this be a high-velocity encounter (to wait for the orbits to line up and do an aerocapture/impact, rather than trying to circularize), but not to hit a bullet with a bullet and do it off-plane. Do you raise apoapsis first, or correct inclination first, or do some phased process, or does it not matter? How would one determine this? How about for other plane conjunctions, N degrees off from the periapsis and apoapsis? First piece of the puzzle I know from very basic orbital mechanics is that inclination is better corrected at apoapsis than periapsis. More than that, I havn't determined. Bonuspoints: How about for other initial inclinations M? Double Bonuspoints: How about for other initial periapses P and apoapses A and target circular orbit radii R in a fully generalized solution?
  3. I just finished up a 12 ton no-docking Moho heavy lander and return mission. 6x (5x xenon, goo tank, gel pod, 2 batteries, 2 6x1 panels, 1 passive panel, 3 legs, 200-size tank, 30kn rocket engine, parachute), plus a central pod with 1x 400-size tank, a one-man capsule, two more 6x1 panels, two passive panels, and an ion engine: No parts were left on Moho. This used some Rockomaxes to get it into orbit, a 3200+atomic transfer stage to loft it through a tight Eve gravity assist, and the rest of the ship made it all the way from the entry to the Moho SOI back to Kerbin. The ions are of course useless for achieving an escape trajectory, necessitating the mixed approach. A long inclination burn and then a high-elliptical apoapsis burn on the way back (after many orbits of waiting and adding maneuver nodes for predictions) let me aerocapture my way (@ 30km)into Kerbin orbit and finally plan my descent directly to KSC HQ with almost empty xenon and liquidfuel tanks. This was around 25 hours gametime of burning, plus many more for orbital maneuvers. No mods, no Mechjeb, no Protractor, no Alarm Clock (though I could have used the last two). Things that were vital: * Just enough solar panels, in a wide enough variety of angles, to assure that you're almost always juiced enough for 100% throttle. A few batteries for if you're forced to make a multi-phase transition on the dark side of a planet (this was a 20-phase final approach to Kerbin for me) * alt + > 4x fast forward mode * Reserving the liquid fuel for landing or taking off, and in my case for a very good gravity assist that took a few times to get right. * Multi-orbit transfer forecasting. Place half a dozen maneuver markers and then modify the first one, and the game will tell you if any of them result in valid transfer trajectories. My last transfer burn to get to an across-system Kerbin encounter was only 1.7m/s and happened five orbits out from the actual encounter, and right after the SOI transition I was moving at 3300m/s, so I had to plan the encounter with Kerbin's atmosphere *long* before the SOI by looking at the post-SOI colored predictions, and make several adjustment burns. *Have a sense of the resonance effect - where coming close to a multiple or the orbital period will end up having the ship moving a little bit ahead or back in relation to the target each orbit * Live, manual transfer correction. Because the forecasted maneuvers are for point accelerations and only go so far, while the ingame map will tell you your current forecasted path very well. * Having something else to multitask on during burns. 25 hours of burning gametime converts to 6.25 hours at 4x speed, but add another 2 hours retrying landing burns and 1 hour on achieving the perfect Eve assist and 1 hour mostly waiting and forecasting for the return trip, and you end up with 10 hours spread over an entire weekend, much of it alt-tabbed to a browser window. * Quicksave. If you're operating close to the line of possibility, you need to use it strategically.
  4. A) Use the x32 grey tank at the bottom and you will completely solve the problem. One octagonal strut, and zero connector struts, will astonishingly also completely solve the problem without introducing any others. I have never, ever been able to do this. I suggest maybe something else is happening.
  5. Onionsparagus staging: The first stage is the entire outer rank (or perhaps most of the outer rank), which crossfeeds using two-way connections until it's all empty at ~3km, then begins asparagus staging.
  6. I would like to ask your opinion not on whether Squad should publish release dates, but whether they should publish blocks of time when no release is sought. During development, patch timing has an impact on mod release pacing and career achievements. This is simply a plan, when 0.22 is released, to say "We're not even attempting to coordinate for a 0.23 release in the next 10 weeks, after that there will not be any predefined release date, but we will be on the path towards a release". It seems like it would mitigate the issue with rigid release dates that can be missed and piss off the community, versus releases which go out on schedule with bugs. Thoughts?
  7. in re: Content - I would like to see the range of celestial bodies in the Kerbol system expanded considerably, by 200-400%, with particular focus on high-dV targets and increasing the diversity of the game.
  8. .Craft will be coming at some point soon, but I really need to test the most difficult part of this - the docking - to see how it holds up. A few extra touches to reinforce the endcaps have brought the part count up by about 50 parts.
  9. 1406 tons and 485 parts after excess engines have been shed (~120T), 9433 tons and 2089 parts in the hangar.
  10. The number of stages periodically broke both MechJeb's dV calculaions and the game's fuel gauges. I went with 3 side by side 4-symmetry branches, for a total of 12 identical structures. The internal rocket motors have plumes that are not long enough to hurt the other endcap, and positioned so that they go right in between the XL trusses that hold the branches in place. The quad Senior docking endcap has guaranteed spacing due to how the quad adapters work, consider this post my first public release of that technique. Not insured in case of unexpected reentry or sudden appearance of moon when it should have been minding its own business.
  11. Or you could out-do my attempt. But it's going to take a while - I have a dozen other tanker designs archived, and 30 different variations on this one. I don't mean to steal anyone's thunder: Consider it a challenge, and a reason not to quit the game
  12. This is the pinnacle of too many weeks of wasted productivity. The equivalent of 36 orange tanks to orbit without much hassle, up to ~40 with an optimal trajectory and switching to nuclear engines towards the end. 8 2.5m monoprop tanks and sufficient thrusters to dock. Double-ended Quad Sr docking interface allows for extraordinarily strong, radially stable docking. 4 atomic engines for orbital changes, 4 LV-909's for reverse thrust without turning around during docking. Optional (staged) separation of 16x Mainsails once near orbit, and 16x LVT30's (manually undocked) once satisfied that orbit is no longer thrust-limited. 1406 tons and 485 parts after excess engines have been shed (~120T), 9433 tons and 2089 parts in the hangar. On my PC, with physics delta set to minimum, orbit takes about 40 minutes. It took me dozens of designs to get something this part-efficient: bundling an asparagus together reliably is a nontrivial task, this does it on 8-10 struts per stack (stacks 2.5 orange tanks tall). Overheating-protected with the power of Octagonal Struts Fully asparagussed down to the last 3 orange tanks. Requires some care during gravity turn to be directionally stable before staging. Plenty of RTGs, batteries, and loads of inline reaction wheels for efficient, fast electric turning. Space for 4 kerbals in a bin somewhere onboard. I can't actually find them, but I can ping their cockpit cameras. I've built larger tankers than this (2100T maximum I believe), but not ones that have been as versatile for playing the game, or as manageable in terms of final part count per unit of fuel.
  13. Your persistence has inspired me to make my absurd quest of the past six months public. Bob Kerman: "Hey Jeb, there's another challenge up!" Jeb turns off the rocket, partially deaf. Jeb Kerman: "Bunch of orange tanks again? How heavy?" Bob Kerman: "Well, 36 tons per..." Jeb: "What? 36 Orange Tanks? Okay." http://forum.kerbalspaceprogram.com/threads/51471-The-KSP-Valdez-Probably-the-largest-useful-tanker pointers: To get this large without crashing, you need to minimize part count. To minimize part count, you need to equalize TWR among full tank stacks, and support them just enough that they don't break off when they're almost empty. Not having a rocket engine underneath during launch is *not an option* due to differential stresses - asparagus and eject if you don't want to use the fuel inside a tank.
  14. No mention of Ike, the little bastard hanging around pushing people out of Dunar aerocapture/aerobraking/targetted landing orbits?
  15. Quite a lot less than 100m in all likelihood. Let's call it 20m - the length of ~2.6 orange tanks, the diameter of 3 concentric ranks of 2.5m asparagus tanks using long radial decouplers. arctan((20 m) / (280 000 m)) = 14.7 arc seconds arctan((60 000 m) / (47 000 000 m)) = 263.316631 arc seconds The Minmas surface should appear (263/14.7) = 17.9x as large on X and on Y dimensions as a ship of those specs, and before correcting for albedo, 17.9^2 = 320x as bright in the sky, as the KSO spacecraft. On Earth, the practical resolution limit from sea level on something 263as wide (dictated by atmospheric seeing) in a static image is going to be an image roughly 50-150 pixels on an edge, and no more. KSO is *much, much* closer than GSO. It is a practical impossibility to image GSO spacecraft with all but the most sophisticated telescopes equipped with laser guide star AO.
  16. So the benefit of a sphere is that it's a compression/tension skin structure which evenly distributes loads, making it incredibly strong - strong enough that you can design it of some very lightweight material if you spread out the loads. A half sphere doesn't have this advantage, and shouldn't be particularly strong against a number of loads - just to make it hold its own form would require considerably increasing dry weight. The half-sphere is not a thing that would be realistically used in any circumstance. A half-sphere might be used in KSP to *portray* a rounded cylinder, which is the typical real-world tank form factor.
  17. Two things in regards to the Munar surface debate: 1) Maria. They're not there right now, and they would make quite a nice feature. 2) The craters? It's fine if there are tons of them, but they need better generation coding: They need a reasonable, *continuous* distribution of sizes, not just a selection of one of a few discrete values. Also, ideally there would be an 'age' variable: new craters are crater-shaped, but older craters subside into mere depressions.
  18. While yes, there are a lot of changes the devs might be able to make to the engines at some point in the future, let's not focus on that. *WITHIN THE CURRENT* perfect patched-conic system, are there free return trajectories with sharper ends inside another SOI than a normal parabola? What do the minimum-thrust return trajectories look like? Is it possible to do a 180 grav-assist on one end, and a 180 turnaround on the other end, and adjust them to balance out using minimal aerobraking & small maneuvering burns? This is not a well-explored system, because we do not live in a solar system where patched-conic equations rule. The kerbals do. What's possible *there*?
  19. The 'ultimate challenge' mission *should* be something at least on the borderline of possible. You're not owed a completion. I would go so far as to argue that there should be a number of bodies significantly more challenging than Eve, *just because*. To give us something to strive for. Things we can't do without some effort, some ingenuity, some work. KSP isn't a rails shooter - this isn't the a boss mob that is standing in the way of the rest of the story - it's a challenge.
  20. What's that Alex? It has to be in the form of a challenge? "Mayday, mayday, our shipment of colonists aimed for the beautiful hydrothermal resort colony on Laythe missed and accidentally landed on Tylo instead! An ion storm has disabled all our unmanned cores in the area, leading to the mishap - it seems that Jeb was the only one onboard that remembered the destination, and when he went offline, nobody could remember which one was the target. When they realized their parachutes weren't working, they burned all but the last 100 units of fuel in a crash landing into a hill. 64 kerbal passengers are stuck there strapped into their habitation pods, spacecraft lying on its side, with nothing but winter coats and their kerosene-powered furnace to keep them warm. This is on the *dark side* of Tylo, without line of sight to Kerbin - and with the ion storm disrupting communications, the only way this message got out is that the 3 pilots used the return stages to burn as far as they could on a tilted ballistic trajectory from the original landing, eventually reaching the *light side*, where they transmitted the message via laser. In light of this disaster, KASA has removed Laythe Venture's launch license with the exception of one rescue flight, but their rocket planners aren't sure how they can possibly move it all there without the whole ship falling apart on impact. Help us Obi-Wan Kenobi, you're our only hope! Launch a craft from Kerbin and land it on Tylo with enough space and enough fuel to get 64 stranded passengers on the dark side and 3 stranded pilots on the other side of the planet to a comfortable landing on Laythe." Does that sound like a reasonable test?
  21. Because on places with more gravity than than the Mun, that can be rather difficult unless you employ Mechjeb every time. I will note that your statement can be adapted: "Adding the ingame landing gear to absorb damage ruins fuel efficiency and gives the ship more momentum during an impact anyway. Why not, you know, don't hit as hard?" The trusses can function as a much more effective and more positionally flexible landing gear than the 'landing gear' included, and I don't see much literature discussing how to use them while minimizing wasted mass, or how much impact they can assist with. So finding out what other people think about that is the goal of this thread.
  22. So the landing gear that's ingame now is horrible for major impacts, relative to a bunch of bendy 0.125T trusses. What's not clear, however, is the optimal arrangement for those trusses. As the game is right now, I would like to establish some sort of conventional wisdom about truss landing gears, and the weight and velocity that they can protect on heavy, fast vertical landings. The restriction is: Lithobraking must cause zero damage to the truss structure. I want a reusable vertical lander, not something that will unpredictably break apart. What have been your experiences with this technique? Pics requested. This, when you remove the nonfunctional wheels (testing something else) will survive a 60m/s landing with zero damage. Note: I am explicitly looking for discussion and feedback on what you guys have tried in this vein, I only included the example to clarify, not to show off.
  23. I've seen this a number of times - but I'm curious - what happens if you bypass circularizing LKO and simply raise apoapsis to escape velocity?
  24. 1) A supernova would induce temporary biosphere collapse ten light years away - 10 or so light-minutes are not getting through it. 2) All that is required to win this challenge is to never use warp, and continuously lob ships up into the sky for ten years.
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