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Largest Payload to orbit minmus


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I'd say there's definitely a fuel bug going on with Caroliano's ship. you lost little more than 50% weight getting to orbit....and with ships in the 800+ ton range, lose over 3/4th of their weight getting to orbit altitude alone, then there's circularizing, then thrusting to minimus, then circularizing orbit around that too. with ships that large, by the time you get to mimimus orbit you should have about 1/7th the weight of launch.

nhnifong, one of the best ways to reduce lag is to make the ship as stable as possible, i.e. not wobbling. that kills FPS tremendously. I had a huge 950 ton ship that got me about 1 frame a second or less. it had a spot between two large fuel tanks that had some SAS and RCS connecting the gap, with some strings attached between the gap for stability.....but it still allowed the ship to wobble ever so slightly. I removed that section altogether and my FPS went back up to a reasonable rate. the FPS drop was probably because when the ship wobbles, it has to calculate the wobbles of everything attached to the ship and probably collision and structural integrity checks as well across the entire ship. couple all that with the fact that the game is single threaded (only uses one CPU) it has to do every series of calculations one at a time, then display the final result. the game code definitely isn't efficient.

And without further ado I present to you not just a ship, but a piece of art.....

The Urchin Class Communication Hub

able to handle the communication needs of an entire solar system thanks to its plentiful omni-directional transceivers.

q8WCQ.png

WSHIQ.png

all stock parts. it's not breaking any records, but it's good enough to steal 6th place hehe. took me FOREVER to get this thing balanced enough to do it. should actually get me first place since my weight is mostly dry weight...only about 2 tons of fuel left ;) could of probably had more weight to orbit if I had focused on a ship with just engines and fuel, but that's pretty bland design wise.

Edited by trekkie_
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Caroliano, were you getting better than 1 FPS on the first stage? I know my machine could not handle that, and it's got decent specs (GTX 680, 3.?Ghz i7, 8GB ram)

I just don't know how you made KSP handle a rocket that big.

Building it! Well, it made KSP crash on some of the rocket mishaps... I don't know if I should even report it...

The first 5km are really a slide show, but not that bad, and mechjeb is piloting it. After the first boosters separation, it gets above 1fps, and is more stable too. The stage I took till Minmus is already reasonably sized for the game, and it ran smooth, but this time it was slow because even with 8 ASAS, this beast takes it's time turn. It helps to be out of the atmosphere too. 4.2Ghz core i5 here.

BTW, I forgot to mention: I'm using the 176 strength large decoupler fix. Besides that and mechjeb, (and kerbal engineer that I forgot to remove) all stock.

I'd say there's definitely a fuel bug going on with Caroliano's ship. you lost little more than 50% weight getting to orbit....and with ships in the 800+ ton range, lose over 3/4th of their weight getting to orbit altitude alone, then there's circularizing, then thrusting to minimus, then circularizing orbit around that too. with ships that large, by the time you get to mimimus orbit you should have about 1/7th the weight of launch.

Well, I think my craft should naturally have a efficiency well above average for those huge ships. It mantains a good TWR during the launch (a previous shorter version even made mechjeb throttle back at launch), so only 37.5% of the delta-V was lost to gravity, as you can see in the ascent status. And this is full of aerospikes: there are 40 engines firing at take off: 36 aerospikes with 13.1 ?/s consumption, and 4 LV-T30 with a fuel consumption of 86.3--74.1 ?/s. Most of the fuel is thus being consumed by those 390 Isp engines at all times. Also, most of the engine weight is at the top, in the stages that reached orbit and Minmus, not as part of the discarded first stages.

So, even w/o the fuel cross-feed bug, I should get the first position here. I don't know by how much, though...

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Only 976 tons on the ground? That's less than my ship that pulled 103 tons to Minimus had on the ground- she checked in just over 1100.

My laptop usually does okay flying anything up to about 1200 tons, go over that or have lots of struts and fuel lines and it gets to a point where by the time you see the explosion mechjeb has already staged up to the next one to counteract the reduction in thrust.

Also most of the fuel-related bugs only appear when the engines are not operated at 100% at all times. Mechjeb only ever uses anything less than full throttle when making course corrections, so other than a possible crossflow issue it shouldn't be relying on any glitches.

Can you share the craft file to see if others can spot where it is happening? Your design is remarkably similar to mine, but I was only using the LVT-30 engines instead of all the aerospikes and boosters.

Here's my 103 ton test vessel. The lander itself is over 30 tons, and carries 3 kerbins in an attempt to land and EVA on minimus

screenshot1.png

screenshot2.png

I'm still working on an uprated version called Alder, but I'm back to the same complexity barrier that I ran into before where if I try to add anything else to the craft it detonates on the launch pad by structural failures. Mind you I'm completely stock over here other than the use of mechjeb.

Edited by OdinYggd
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Only 976 tons on the ground? That's less than my ship that pulled 103 tons to Minimus had on the ground- she checked in just over 1100.

My laptop usually does okay flying anything up to about 1200 tons, go over that or have lots of struts and fuel lines and it gets to a point where by the time you see the explosion mechjeb has already staged up to the next one to counteract the reduction in thrust.

The performance seems to depend more on the number of parts than the total mass. Your rocket uses basically big parts and big tanks, so it is lighter on the engine. I may have overdone in the structs also.

Also most of the fuel-related bugs only appear when the engines are not operated at 100% at all times. Mechjeb only ever uses anything less than full throttle when making course corrections, so other than a possible crossflow issue it shouldn't be relying on any glitches.

Can you share the craft file to see if others can spot where it is happening? Your design is remarkably similar to mine, but I was only using the LVT-30 engines instead of all the aerospikes and boosters.

I don't think it is so similar. My design is centered on bringing fuel for the maximum number of top aerospikes to fire simultaneously, so that the average Isp of the engines is quite high since the start. And this variety of fuel flow configurations I use to reach this goal probably triggers at least one of the crossflow bugs present in this version... The below 100% throttle bug is only one bug, and I made the same effort to avoid it as the other people here did.

My craft file is in my first post on this thread, on the mediafire link. I may upload as an attachment too.

I'm still working on an uprated version called Alder, but I'm back to the same complexity barrier that I ran into before where if I try to add anything else to the craft it detonates on the launch pad by structural failures. Mind you I'm completely stock over here other than the use of mechjeb.

Try using the large decoupler, with the strenght fix. But this still leaves the engines. I tried to use those small engines like that in the second stage, above the LV-T30 engines, but they were crushed under the weight of the top of the craft. So, I ended up putting they on the sides too.

Edited by Caroliano
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Well, I think my craft should naturally have a efficiency well above average for those huge ships. It mantains a good TWR during the launch (a previous shorter version even made mechjeb throttle back at launch), so only 37.5% of the delta-V was lost to gravity, as you can see in the ascent status. And this is full of aerospikes: there are 40 engines firing at take off: 36 aerospikes with 13.1 ?/s consumption, and 4 LV-T30 with a fuel consumption of 86.3--74.1 ?/s. Most of the fuel is thus being consumed by those 390 Isp engines at all times. Also, most of the engine weight is at the top, in the stages that reached orbit and Minmus, not as part of the discarded first stages.

T:W has nothing to do with the amount of delta-v it takes to get a craft to orbit. More engines or higher T:W != more delta-v, only higher Isp and more fuel = more delta-v. It takes on average around 4400m/s of delta-v for a low kerbin orbit, around 75km. Your craft started at 954.5 tons and you got 342.5 tons into orbit. Even if all that weight you lost was fuel, that would be a maximum delta-v of 4000 (w/Isp of 400), not enough to get into Kerbin orbit. The problem is, that first stage isn't all fuel, and your Isp isn't 400. You have those heavy empty tanks, engines, and everything else. I added them all up and your first stage actually only has 376 tons of fuel and a total weight of 477 tons. At an Isp of 400, that's only 1964.27m/s of delta-v.

That doesn't even take into account the fact that more than 1/3 of your thrust (4800) is from horribly inefficient engines that have an Isp of 280 in Atmo. You get 9000 thrust from the aerospikes. So your Isp in your ascent stage is nowhere even near 400, it's actually 351.74 at launch and maxes out at 373 in vacuum. So your first stage delta-v is actually below 1900m/s. (Somewhere between 1700-1800m/s)

Your second stage starts with 471.1 tons and gets to Minmus with 270.2 tons left, has an Isp of 390, and used a delta-v of 2174.52 m/s. Adding the delta-v of the two stages is a total of under 4075m/s of delta-v. Not even enough to get to orbit, let alone to Minmus. So yeah, there is definitely a fuel bug here.

[Edit] I am actually checking my craft now too, because it just doesn't seem right, but mine is far harder to calculate because of the amount of staging and the way it works.

[Edit2] Yep, there may be a fuel bug in mine too, I need to figure out how SRB's calculate into this. I know it wasn't from low throttle because I have the fix for that and I also fly at full throttle just in case. I thought the other bug was from directly attaching lateral tanks, but now I'm thinking its in the fuel lines. Boy oh boy , .17 going to have a new learning curve.

Anyone know how to calculate how much delta-v you get from SRB's?

Edited by Ziff
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Anyone know how to calculate how much delta-v you get from SRB's?

ISP is the average of the engines weighted by Thrust.

The you just factor in the liquid fuel used under SRB boost for that stage full and dry mass. You can calculate that, but with it's probably easier to estimate from a test flight.

Edit: Oh, and the values are...

Small SRB Imp 440 Thrust 250

Large SRB Imp 204 Thrust 400

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Wow, I asked that in the dumbest way possible. I totally need to get more sleep but thank you for understanding what I was getting at. Yeah, I can calculate that no problem. Also, I didn't realize SRB's also had a full/empty weight, I had just been looking at their thrust and burn time.

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Ok Folks

1.014,9t at launch

85t orbiting 1.725x1.737km Minmus

that looks like a FIFTH place right now - Name of the Ship is "Artemis B".

on ramp:

http://imageshack.us/photo/my-images/844/screenshot192f.png

upper stage in parking orbiting

http://imageshack.us/photo/my-images/571/screenshot193t.png

orbiting minmus

http://imageshack.us/photo/my-images/198/screenshot196s.png/

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I quess I'll post this...

Minimus GigaCraft #0 - 1648,1t on launch - 123,5t while orbiting Minimus.

All stock - except Jebediah's brain.

http://s16.postimage.org/byxwufc83/screenshot57.png

http://s9.postimage.org/5miwdavzj/screenshot66.png

http://s7.postimage.org/sf0ta1lkb/screenshot74.png

http://s15.postimage.org/gh9wkt5kr/screenshot76.png

PC get's all laggy with bigger ships...

Perhaps time to consider buying better cpu.

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Well, I think I stole 5th place with my ship, the OL-Titan MK3. 666.6 tons on the pad and managed to get 94.3 tons into orbit around Minmus.

On the pad

KSP2012-08-2112-07-16-22.png

In LKO at 75km

KSP2012-08-2112-13-11-16.png

Main injection burn to Minmus

KSP2012-08-2112-27-02-97.png

In orbit around Minmus

KSP2012-08-2112-05-10-42.png

Unfortunately, I think there may be a fuel bug in the launch stage, but I'm not sure.

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Ok, so how do I display mass? :)

screenshot13vj.png

screenshot14ed.png

Just from adding up the components, The center rocket is completely full of fuel, and 5 full tanks at 18 each, should mass 90. The 4 side rockets have almost a single full fuel tank each, empties mass 2 each, so if they were all completely empty that would mass 40. The engines are 7 each, so 35 total there. So that would be a total of at least 165, plus another 11500L of fuel or so. The side bottom tanks are over 7/8 full, so I think that should be 14 mass worth of fuel in each, for an extra 56, bringing the total up to at least 221 or so. :0.0:

If it's non-rocket payload mass, I could replace 4 tanks from the center shaft, and 1 from each of the side ones, and I should be able to bring up 144 worth of non-rocket payload with a bit of fuel (1900L or so total) to spare, left over in the center fuel tank.

This absurd ship is the SunGrazer, all stock parts, no mods, no addons:

screenshot0cu.png

I used a slightly modified version to do this: :)

sunimpact.png

(and adding a small rocket with 3 full size smaller fuel tanks and a rocket on top works and gives even more delta-v, enough to zero out my velocity around the sun with lots of fuel to spare)

I tried to make a bigger one that had 19 main rockets, that could separate them 2 at a time to orbit as they got empty (fuel being pumped into the remaining rockets, so whenever there's a detachment, all the remaining rockets are always full on fuel), and I could almost get it to work, but things kept occasionally detaching and blowing up. This one drops off 4 at a time, pairs on each side, as they get empty.

Takeoff mass, from what I can tell, is close to 1470.

screenshot10pi.png

screenshot12k.png

I got a bit lucky on the transfer orbit, although I did have to turn around and burn the other way and off to the side a little bit near Kerbal to get it right, but not much, and got it on the first pass, and didn't have to wait to loop around again. I really should put some RCS on this thing, it's a pain to have to turn the engines on slightly just to steer. :)

Edited by Soralin
Fixing spoiler tags.
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This one would also qualify. :)

screenshot115g.png

screenshot116r.png

screenshot114l.png

The vehicle on top has 7 mass 7 engines, 7 mass 9 fuel tanks, 6 mass 4 engines, 6 mass 2.25 fuel tanks, all full, for a total of 149.5 (plus various struts, landing struts, RCS, the command capsule, etc.) The bottom section has 2 mass 7 engines, 2 full mass 18 fuel tanks, 2 empty mass 2 fuel tanks, and 2 fuel tanks over 7/16 full, for 9 mass each (2 for the tank, 7 for the fuel, which would be 16 when full), for a total of at least 72. Together, it would mass over 221. Hmm, similar to my last one, this one is probably a little heavier, from the stuff that's harder to estimate, and the true weight of both will be a bit more than that, since these are strictly underestimates.

Our delivery rocket:

screenshot129mt.png

More detail in the Knock Minmus out of orbit challenge. :) : http://kerbalspaceprogram.com/forum/showthread.php/18026-Knock-Minmus-out-of-orbit%21-Challenge?p=247866&viewfull=1#post247866

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Managed to get my new prototype Hercules 'silly systems' transport vessel (start weight 781.8 tons) with 287.6 tons of weight left in orbit around Minmus. (all stock except used mechjeb module in the end to get the angle right to minmus :F). Ship is actually incredibly stable and capable of carrying more weight into orbit, not just minmus orbit..

Vehicle basically consists of 9 LV-T30 and 15 LV-T45 engines which simultaniously fire for launch. Ship lifts a total of 96 FL-T400, 19 FL-T32 and 12 FL-T16 fuel tanks together with some tricouplers, decouplers and mostly struts to keep stuff from flying their own way.

Vehicle is stable at full throttle but here I launched and got into orbit at a bit lower thrust (see launch image). Kept this trust and boosted where neccesary to get in orbit, full thrust boosts for the rest.

Whole mass can be seperated from the main vessel, consisiting of a command console, struts, some ladders and LV-909, supported initially by 3 x 5 FL-T400 tanks and 3 T45 engines (which are still 100% fuel when in Kerbin orbit). But didn't do that here :').

At launch, actually I should still build boosters around it to launch it (for this flight, only used some help from aerespike rocket with 2 fuel tanks to test).

I fly up till about 5Km, then I steer to 60% and keep this angle till apoapsis is about right (min 70km but it's actually nicer to go into a 1 million orbit eventually to be able to steer this slow mofo into Minmus).

Out of the 9 T30 rockets, 3 of them will run out of fuel soon enough (usually at about 320m/s); these rockets together with 3 FL-T32 and 3 FL-T16 fuel tanks are seperated. Rest flies all the way to minmus in this case.

Hardest thing about this is to steer it where you want when you can't really use any acceleration; it's quite slow to turn and you need throttle. Haven't experimented with thrusters on the side or something.. Out of frustration I ended up using mechjeb for orbital insertion, just to get the angle right, rest of insertion had to cancel Mechjeb because it ended up rotation the ship too fast every tme.

Can put .craft file online if you want; dunno where one can upload such thing though

herculesqltdx21.png

herculesqltdx21b.png

herculesqltdx23.png

herculesqltdx25.png

herculesqltdx26.png

(pic of launch and below views were taken later as I forgot to make them; but it's the actual vessel used (and it's actually repeatable with same ship)

Edited by Qyn
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Hmm, ok reading that I am not conviced of my thing, hehehe :P

But hmm, if I put 9 more T400 tanks on top of mine and about 12 T32's extra.. This time used full throttle from start to Kerbin orbit and as much as possible later. Ended up at 280 tons to get in Minmus orbit this time (and almost out of fuel), bit sloppy steering so had to make lots of corrections to actually reach orbit. Although I guess it's bugged after all because even the small engine bursts for corrections or to create some acceleration for steering feel like cheating now :P

borgx21.png
borgx22.png
borgx23.png
borgx24.png

Ship: http://www./?zws9y8sxaga9v7w

(was just for fun to try and lift long heavy weight in construction using tricouplers, bit sloppy and oops think I left mechjeb module on top)

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This ship wasn't specifically designed for this contest, it's actually my design for the upcoming planetary flights, but I figured I'd post it 'cause it lofts a respectable mass into Minmus orbit.

screenshot9f.th.png

screenshot12x.th.png

screenshot14j.th.png

702.9 tons on the pad, 32.7 to Min orbit. The rocket gets SRBs knocked off the side if I launch it from the tower, so I had to launch from the spaceplane runway :D So far this is my most successful heavy lift rocket.

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The rocket gets SRBs knocked off the side if I launch it from the tower, so I had to launch from the spaceplane runway :D

That's actually pretty clever, hadn't though about that.

You can move it sideways a bit if you only need a little room, so that's what I've been doing so far.

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