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funk

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Posts posted by funk

  1. 9 hours ago, michal.don said:

    That's an example of fine piloting skills, especially the very steep reentry and a precise landing. I'm curious though - did you nail in on your first try, or was some iterative trying needed to get the landing location right? :) In any case, great mission, and a well-deserved badge for you. Congratulations!

    Thx for the batch. I did one  test flight mostly for testing the angle between launch site and mun. It was fine and I could have finished the mission, but at one point instead of activating the engine, apollo decided to decouple the service module.

    For the landing itself it wasn't that hard to get it right. I knew that the time to periapsis at Kerbin has to be less than a multiple of six hours, when setting up the free return trajectory. The second correction was just eyeballing the time between PE and the position of KSC. In fact I overcorrected a little bit and the reentry was almost too short, imho slight overshoots are more forgiving.

  2. 2 minutes ago, 4x4cheesecake said:

    Looks like a combination of the jr. and 'regular' sized clamp-o-tron.  

    This! Just clipped into each other.

     

    6 minutes ago, 4x4cheesecake said:

    Also, which sunflare mod do you use? It looks amazing!

    Sunflares of Maar - UrsaMinor. At least the gamedata folder says so. I copied it from my 1.4.3 install.

  3. Funkyndustries is back in business! RL doesn't give me a lot of time for KSP, so I had to get rid of all unnecessary orbits and play-arounds for STS-5T. Straight to the Mun and back!

    One question though: Are the test missions ment to be accomplished with the same craft? I'm asking because my Energija already has recoverable boosters and I'd just need to finish my catamaran for STS-6T to bring them back. The STS boosters aren't recoverable by design.

  4. 12 hours ago, Kerbolitto said:

    There will be 0 simple aim and inject in this mission :D

    Recommending this as a second title of the challenge...

    12 hours ago, Kerbolitto said:

    Should I put the whole SLV03 to Minmus and refuel tanks to the max (3k9dV - 0.22TWR) or launch from Kerbin just a little time before the transfer window (1k1dV injection / 1kdV capture - 0.27TWR) ? Round trip to Minmus with ISRU and fuel tanks take approx. 25 days, launching from Minmus would reduce that time to 10 11 days before being able to inject with full tanks but if Minmus is on the bad side I'm screwed (got 66 days before optimal transfer).

    Minmus has as a period of what - 50days or so? You should be fine. But is the additional fuel needed?! The pilot ususally knows best.

  5. 7 hours ago, meyst said:

    I used an outbound Aldrin-Cycler (S1L1) cycler myself. Some problems I encountered ironing out the bugs of that outbound orbit; 

    Expecting to always see a Ballistic Trajectory on the Kerbin gravity assist (usually but not necessarily always the case due to the angle needed on the gravity turn. [This is even more true of an Earth<->Mars Aldrin-Cycler])

    Not recognizing/correcting course/orbit deviations early enough. Errors escalate every orbit.

    Orbital duration, drifting/not in sync with the Synodic orbital period of Kerbin and Duna, 19 645 697.3 seconds. I settled on an outbound Kerbol (solar) orbit Ap of 31 505 200 km and Pe of 13 400 000 km but anything that matches the Synodic period should work.

     

     

    I strongly suggest you test that inbound Duna>Taxi>Aldrin-Cycler>Kerbin transfer before committing to it. That one is a surprisingly high Delta V intercept for the taxi and not the easiest thing to fly either.

       

     

    Thx for your recommendations. So far I'm done with both cyclers and the taxis. Thx to this I found the trajectory easily. Two things need to be adressed.

    1. Don't enter Dunas SOI, it's screwing up everything

    2. My test gravity assists at Kerbin are somewhat of inaccurate due to wonky SAS and I guess low TWR

    Further the dv requirements for the taxis are simply ridiculous. For a Kerbin -> Cycler transfer it's ok with 1500m/s + 100m/s to enter Dunas SOI. But Duna -> Cycler transfers are about 2600m/s. Because I want alternating taxis I need nuclear propulsion, so no aerobraking. Makes 4300m/s dv for the taxis. It's viable and the test results where ok, but the margin of error is small (~200m/s) on one leg. Further there will be refuel missions for the cyclers every two periods with a tanker also alternating between the cyclers.

    I found several ways in some papers to reduce dv, but it didn't fit the challenge well. E.g.doing two Kerbin grav assists conflicts with the timeframe, adding more cyclers could fix that, but conflicts with mission efficiency.

    Another way would be repeating small burns along the trajectory, but I don't have the time to code a solver for this in KSP and it's just tedious to perform so many burns.

    Overall I think my designs and mission plans are 80-90% done and hopefully I can start in a few days... rip spare time.

     

  6. Great stuff @Death Engineering! May I ask, why the supply module has four Klaws?

    Just a little update on my plans how to implement the cycler:

    EdYnx6C.jpg

    Due to insane amounts of dv needed for the taxi, I won't be able to fullfill the requirements for "Advanced deep space transit", in spite of that the taxi itself could do it, only the crew needs to shrink from 12 to 6 Kerbals.

    This slides  gave me some inspiration for my planning. Even if there are some realworld attempts to use low-thrust cyclers to reduce dv needed, its barely viable in KSP. That's why I'll take the approach shown in the picture.

    Still need to do some work on the outpost, stations and launch schedule... hopefully next weekend.

     

    Edit: There'll be an inbound cycler implemented as well, it's just the other way around.

  7. 23 minutes ago, Alchemist said:

    Duna Space Station - yeah, the question of likely high-latitude operations leaves a huge question of where to place the station - polar orbit makes huge issues with interplanetary transfers, equatorial orbit has issues with high latitudes. Probably equatorial orbit is better overall.

    Was thinking about the same... Best place would be probably Ike, but your taxis need to be capable to go there.

    23 minutes ago, Alchemist said:

    ife support sustainability: water seems to be fully recirculated if you don't spend it in converters,  oxygen regeneration from CO2 is not 100% self-sufficient, but when you can pump some extra CO2 from the air

    Is there CO2 on Duna? Haven't played with TLS for a long time, that's why I'm wondering. Just figured out, that if you run Sabatier process O2 is self sufficient but needs ~ 1u water/7u food resupply. Does TLS implement more resources to harvest?

  8.  

    4 hours ago, michal.don said:

    Or do I have to have three separate vehicles on the surface (The main Duna Ascent/Landing Vehicle, The Backup Ascent Vehicle, and the Sufrace/LDO shuttle for the "Duna Shuttle Service")?

    I was wondering, too. Let's say I want to rotate the crew on Duna. In this case will I need 2xDAV, 1xEEV and the shuttle? Or can one DAV be enough if it brings the old crew to Duna orbit, like a taxi from Duna to DLO? Then it can either wait in DLO for the next crew or it can go to the surface again and serves as an emergency ascent vehicle (NOT ment as EEV).

    Fur the Duna-Ike Space Bus the OP says "refueling permitted". Is it allowed to refuel on the surface of Duna/Ike only? Or can it refuel also in orbit?

  9. 2 hours ago, michal.don said:

    They just sort of "feel right" to me, I guess this is the kind of things I would build, if I was skilled enough :D

    Understatement...pff! It seems I feel some irony here... Form follows function and laziness equals efficiency - most of the times. I guess you realised that the payloads are just tweaked copies of your work. So I'll give the credit back to you.

    Anyway, thank you for the badge.

  10. 3 hours ago, Death Engineering said:

    I do like the 20t approach by @funk. I did well doing the original challenge with 30t, but things were a lot different back then.  So many launches!

    After some more testing, my assumption, that the shown SLV is kinda overkill for 20t, was true. Now I'm able to lift 45t to 100x100km LKO with the same design, just optimizing flight path, no mods etc. 50t might be possible with a script or mod, its just 100m/s short to circularize in LKO.

    From my plans for the first launches: 2x24t before the first cycler burns for duna is optimal. So 1x48t could be a thing, but I'm not sure which kind of payload would be that heavy (except fuel) and fits into the fairing (I don't like the kinda not streamlined fairings too much - just for the looks). Additionally I still need to design the payloads and plan the flights after year 4. Maybe there will be changes, due to optimization.

    Further, when I looked through my crafts, I found a 18t payload F9 clone, that also could be used...

     

    Edit: Totally forgot to ask @Death Engineeringabout the inflatable airlock, it technically could be counted towards habitation space, but most likely cheety. Will you treat it like the external seat?

  11. 3 hours ago, michal.don said:

    In the process of my planning, I was a bit confused about the timing and durations of transfers/orbital stays etc. So, being an engineer, I created a chart :D

    Great minds think alike I guess. This mission is the first time in KSP thinking about creating a network for the missions. Stuff I do on my daily basis, only costs and annoying customers are missing :wink:. And with your work I could've relaxed yesterday evening. THX alot!

     

    9 hours ago, Blasty McBlastblast said:

    Has anyone else encountered this or know of a solution?

    It happens, when the landing legs are overstressed. Not sure, but I thought it's fixed in KSP 1.4.4. You'll either need the heavy landing legs or you could use e.g. airbrakes/beams as legs. As far as I see from your picture you're testing on Kerbin. For Duna you might get away with less stress due to gravitiy. "Hack gravity" can be useful for testing.

     

    8 hours ago, Kerbolitto said:

    Another thing that also really bothers me are structural tubes (not 1.25, the new ones from Making History), they can't whistand a lot of pressure and radial wheels fall appart if you try to jump with a big rover ..

    The strength of joints in KSP are based on the mass of the part another part is attached to. So the tubes are very light, every part connected to them will have a weak joint. Autostrutting might help. Or the best way would be to attach the wheels to another heavy part and offset them. For the pressure thing I'm not sure what you mean, but tubes don't occlude parts inside from airflow.

  12. 2 hours ago, Kerbolitto said:

    I'm currently flying the first steps of this challenge, here is a little spoiler of what's coming up !

    Holy!  I'm not into payload building, yet. But this looks massive! Did you launch it in one go?

     

    My sunday afternoon was dedicated to a first iteration of a SLV:

    Album a/oSvsDHE will appear when post is submitted

    It's rated for 20t payload only, cause I think it should be enough for what I imagine as my future payloads. But it should be capable of more, when I've found out the best ascent path for it. And a boost back doesn't give any benefit for the challenge compared to a barge or whatever landing along the ballistic curve. Additionally the second stage has 1k m/s dv left before payload decoupling and my attempt to hover slam was on the safe side.

    I tried a shallower ascent path but the time to maneuver the two stages is really short if you don't leave the atmosphere. Haven't played with physics range extender yet. @Death Engineering Would it be allowed to use?

    Maybe I'll write a script for the SLV. But it all depends on what is really needed payload wise.

     

     
     
  13. Great challenge reboot. Didn't try in the past, but when I read the mission profile, I instantly thought: "Finally I have a reason to try out an Aldrin-Cycler to Duna". I'm by far not sure how to do it, especially how to find the right trajectory. So far I was playing around with some flybys, but it breaks after some circles. I'm not even sure yet, if it is possible at all. But I'll try.

    Q: If I use a SLV with different NPM, like an Atlas V with a different amount of boosters, will the minimum time between launches be different too?

  14. 1 hour ago, michal.don said:

    Out of curiosity, what are the d-V requirements for correction burns in this kind of transfer? Do the planets send you the right way on their own, or are some larger burns requirerd?

    Best case, it's only the transfer burn. But their are so many variables like timing, burn, thrust angle offset through SAS even when your craft is symmetrical etc. that at least I needed some minor correction burns. I found, the cheapest way is to burn right after you leave the flyby-planets SoI. Only 3-5 m/s per burn. For fine tuning it's more like 0.1m/s. The closer you're to the next planet the more expensive it is, but easier to perform. For K-E-K-J I used totally about 15m/s dv.

    I would advise you, if you like to do this kind of maneuvers, that you get used to flyby finder. When you've found a window decrease the search period to 50 days or so for departure. Then FF will find a lot of possible transfers. It's easier than you would think.

    Last important point has to do with KSPs solver. You will only see the next encounter (when your craft crosses the orbit of the targeted planet). So adding an additional (0m/s)maneuver node on the resulting trajectory helps to find the next one /(x orbits later and so on).

    2 hours ago, michal.don said:

    Being an engineer myself, I can add my bit of expertise and confirm that sets of non-linear differential equations are pure evil and caused me many sleepless nights in my school days..... :D

    Yeah diff. equations and headaches sounds familiar. Because I'm more on the electrical side, transformations and discrete math is more common and way easier imho. And for the mechanical part I was glad when I passed it. Nowadays I only need it for KSP ... thankfully.

    14 hours ago, hoioh said:

    And then there's the hylarious option we've all seen recently which is to grab it underneath the shuttle and play soccer with it

    Ehem... it's still called football :wink:.

  15. 1 hour ago, michal.don said:

    How often do the planets align for this kind of Kerbin-Eve-Kerbin-Jool transfer?

    Thx again for the badge.

    I'm not absolutely sure, I'm using flyby finder and just from a quick search, the next low energy window was approx. 620 days after the one I've used. I don't think you can generalize it, cause even when Eve and Kerbin are in the same position relative to each other again, Jool has moved a bit further so the K-E alignment will have to move further too and so on. There will be some kind of tipping point where the alignment needs to be "restarted". Then you'll probably have a longer period to the next low-energy transfer.

    As far as I can remember and without any further proove and me being an engineer with basic mathmatics/physics background only, the tipping points are one reason why non-linear systems of differential equations, like the three body problem or in chaos theory, need to be solved numerical.

  16. 7 hours ago, michal.don said:

    Also, I checked the previous version of the challenge, and found out that this version has the most replies of them all - so I'd like to thank you all for the interest in shuttle flying!

    No really, thank YOU for keeping this challenge alive with all your effort and time you spend.

    7 hours ago, michal.don said:

    Would you prefer to explore new worlds we haven't visited yet, or should I make the missions to develop functioning, complex infrastructure around and on the planets like Duna? 

    It depends... basically it comes down to building (LV/Orbiter/Payload) and maneuvering skills (Transfers/FlyBys/Docking/Landings). In that regard the missions should be from entry level up to master level.

    What stock KSP doesn't teach you well is timing (compared to RSS). Maybe there are some ways to limit a mission's parameters to reduce the margin of error.

    IMHO the missions shouldn't be too repetitive, e.g. sending an orbital station to Eve is more or less the same as sending it to Duna. Same goes for bigger stations (more flights).

    I was reading some stuff about the upcoming Parker-Solar-Probe and came across Ulysses which could be a medium mission to show newer players how to use Jool to get to the sun for cheap. On the other hand it would be similiar to Cassini and is more about flying the probe instead of the shuttle.

    A mission to Moho, Eve, Tylo can be challenging but doable (Alchemist). In 1.3.1 I've built a "shuttle" which disintegrates itself to a LV with another shuttle on top, to land on Eve and return to Kerbin. Also visiting easter eggs might be a thing. A grand tour with a shuttle (all-in-one or separately) would be the ultimate mission I could think of, but would interfere with other challenges except for doing it with a shuttle.

    Overall I think the existing missions already cover a lot of use cases and it probably won't be easy to create new ones or filling niches.

    2 hours ago, hoioh said:

    Do you like the "test pilot" missions? Should I make more, or should I focus on the regular, big ones?

    I don't mind. Maybe the test missions are da way for more restricted missions.

    2 hours ago, hoioh said:

    Do you like the "reading materials" I sometimes include in the mission description, or are the pointless?

    At first I was like: "I don't need that bs - let me build and fly". But tbh when I build, I read myself so many additional stuff, which I wasn't realizing until RTLS and for that it showed me how amazing it is to have some additional information I'd probably never stumbled across, without your links. So I'd say keep it, if you've informations but don't force it.

     

    What I like the most about this challenge is its wide range of possibilities and creativity without a lot of constraints. It's about what you yourself want to achieve (sandbox feeling). Keep that spirit!

  17. @michal.donI hope you've had a nice week. In pictures likes this it always impress me to see how nature recovers and reminds me that it will still be there when humans are gone.

    Regarding the challenge, for STS-3T the description says: "The Cassini probe must weigh at least 1,5 tons, the Huygens lander must weigh at least 1 ton"

    Am I correct that this is ment to be mass or weight on Kerbin sealevel? And does the lander need to have a fuel tank? Because I'm planning to send it to Laythe without an engine. Cassini will only have the torodial tank.

    Thx in advance.

  18. 10 hours ago, michal.don said:

    And I really like your shuttle design - would you mind sharing the craft file, so I can examine how exactly it works and fly it a bit?

    Yay, another batch! THX!

    You've forced me to fix some minor design flaws today and it should've been tested more, but it's time to face the public now. I've recently uploaded it to kerbalx (s.sig.) Have fun!

  19. 22 hours ago, michal.don said:

    The RTLS isn't easy, when the engine switches off, the shuttle starts really fighting back. In my run, it was a wrestling match all the way to space.....

    I've done some tests with 18t payload and I think I have it under control now - with the help of RCS and using the OMS to gain altitude. Further I understand now what is mentioned in the article about energy management when you need to burn all your fuel but also reach KSC in the end.

    Here is the obligatory STS-1T mission, which wasn't really a thing, cause the crafts had been tested and flown several times in previous versions of the challenge.

     

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