The Eve Rocks Challenge (v0.90 only)

[Laie]

Anybody see the glaring flaw?

After much squinting in the shadows: Can it be that two of your inner engines are blocked by some kind of structure?

[James_Eh]

After much squinting in the shadows: Can it be that two of your inner engines are blocked by some kind of structure?

Nope. One of the fuel lines in the inner asparagus thingy is no longer attached to the tank to which it should be. You can see the little nub of the fuel line leading nowhere. I have run into this repeatedly, fuel lines and struts suddenly forgetting to where they ought to be attached. Sorry about the darkish picture but it seemed to me to be the best illustration of the issue. Shortly after I posted this, and shortly before the horrible end of the mission, I had a shot of the same issue front-lit by the sun which would have been a better post.

Ah,well, it was, as they say, a (long) simulation and now I am getting ready for the main event.

[Ziv]

Laie, that rover looks pretty cool!!

My Eve Rocks Expedition finally reached the launch state - the Eve surface-to-orbit Return vehicle with some structure is already in Kerbin Orbit. I will add some base buildings to it but realized that my command module, plane and rover would be too much on part count so I can't send them to Eve as one huge ship. I was designing my stuff to be low on part counts but it become too much anyway.

But anyway, the Return Vehicle will automatically land (no Kerbals yet) on Eve with the base at the same time. The base buildings have parachutes but the Return Vehicle will do a powered landing next to a pond because somebody said parachutes are too weak for it (I guess I heard that engineer behind me whispering about some Jebediah's Level or something, I don't know what they are talking about)...

And then I will send the crew (3 Kerbals) after the automated first one, with a plane and a rover. They will inhabit the base and use the plane and the rover to make an extensive expedition on the surface.

There are some classified engineering solution going on so no pictures yet.

[James_Eh]

Well this is interesting. Doing the main mission now and am coasting to Kerbin escape. I am using 6 tanks (2 LV-N's apiece) as the drive section to get to Eve. I didn't set them up in asparagus fashion, but figured I could transfer fuel and blow off 2 or 3 of them whenever convenient between burns.

So I just checked the fuel levels on all 6. Starting from one at random, moving clockwise:

955 974 971 975 982 972

????? This ship is very very laggy. Is there any chance of this being just related to calculations and calculation cycles? What I'm wondering the most is: Is there any possibility that the tank with the lowest level of remaining fuel was at the "bottom" (ie closest to Kerbin) of the ship during the escape burns and possibly used more fuel for steering? KSP doesn't work like that does it?

EDIT: Even cooler. I chose a tank at random and transferred fuel to the tanks to the left and right of it until they were full. It left a teaspoon of fuel in the "from" tank. Then I did that again with the tank on the opposite side. And everything balanced! The two nearly empty tanks have exactly the same amount of fuel. This must have something to do with the fact that almost everything is 6-sym, but there are two fairly heavy bits at the bottom of the craft that are 2-sym. (?)

Edited November 28, 2014 by James_Eh

[Wavechaser]

No mods... ...aw... ...

I already have one Eve ascend vehicle that works perfectly with some KW tanks, MechJeb (removable) and RealChute (removable), but the biggest part is, the KW tank.

It doesn't kill to just have KW installed...

[James_Eh]

Laie, you magnificent beast. You forced me to finally conquer my Eve fears and send a Kerbal to the surface, with the implicit assumption that an ascent would be part of the plan.

Anyway, the brave lander is back at 120x110 and awaiting the shenanigans of the crew in the luxurious hitchhiker as they match the 30 degree inclination difference and come to grab him. Pix to follow once I can Imgur them up into an album.

[Laie]

I already have one Eve ascend vehicle that works perfectly with some KW tanks, MechJeb (removable) and RealChute (removable), but the biggest part is, the KW tank.

I guess the majority of mods would be perfectly alright, but finding out takes time. Lest everyone & their little daughter asks me to greenlight their favorite mod, I decided to not even take a first step down that road. Sorry about that.

Laie, you magnificent beast. You forced me to finally conquer my Eve fears and send a Kerbal to the surface, with the implicit assumption that an ascent would be part of the plan.

Glad to hear that Eve deserves more attention that she's getting, IMO.

Sorry about not reacting to your previous post, I somehow missed it. Check out Kasuhas' Fuel Flow Rules (no link handy, but that's the title and you find it in the tutorials section). No need to memorize all the rules -- but you will understand how switching from 6x to 2x symmetry can mess up everything.

Simple rule of thumb: there can be as many fuel lines leading into a tank as you like. But if there's more than one going out of it, bad things can happen. If you end up building a loop, it's nearly certain that bad things will happen.

[James_Eh]

Sorry about not reacting to your previous post, I somehow missed it. Check out Kasuhas' Fuel Flow Rules (no link handy, but that's the title and you find it in the tutorials section). No need to memorize all the rules -- but you will understand how switching from 6x to 2x symmetry can mess up everything.

Simple rule of thumb: there can be as many fuel lines leading into a tank as you like. But if there's more than one going out of it, bad things can happen. If you end up building a loop, it's nearly certain that bad things will happen.

No need for apology, we've all got lives... But I'm sure the issue has nothing to do with fuel flow, there were no fuel lines involved with those tanks whatsoever. They sat on the outside of the ship attached by radial decouplers. When I get my pix onto Imgur you'll see what I mean. It's a mystery to me. Once I manually pumped 4/6 of them full by draining the other two, and threw away the empties, the levels stayed rock solid. I still think it had something to do with weight distribution in my ship but it's a topic that likely belongs somewhere else, I plan to investigate.

EDIT: Aha. It had nothing to do with neither fuel flow rules, nor weight distribution, and everything to do with the somewhat inexact process of transferring fuel INTO those tanks from the two leftovers from my booster that made it into orbit with me.

Edited December 3, 2014 by James_Eh

[SkyRex94]

one question:

there is this rule "there have to be pods/hitchhikers for all Kerbals involved. No seat-only lifters."

What if there is no Pod for the Crew... but no seat either? And if they are 'inside' something? (aghhm..cargo bay...)?

[James_Eh]

OK, I am utterly mad. We came. We landed. We ASCENDED!!! We rendezvoused with the return ship. We transferred to it flawlessly. We headed for home.

And I ran out of fuel during the burn from Eve to Kerbin. I stupidly didn't notice until very late in the burn that for whatever reason KER was reporting the dV available in my return vessel as far far too high. I don't think this is a stupid mistake on my part like my worries about fuel above. This seems to be some kind of crazy bug in KER which led it to report my available dV as something like 7000 when in fact it was half of that. The worst part is I designed the return ship with 3500 in mind, but then once it was free and KER started reporting 7000, I kind of spent some time flying less-than-optimally...

What follows are two pix. One is of the lander safely on Eve. It ascended and I had almost 1000 dV left to boot. The second picture is of the simple return ship making a burn to match the orbiting Kerbal's inclination. Note how KER is reporting 6000+ dV. This ship, fully fuelled, only has about 3900. I have no idea where the KER display is coming from. I just tested the same vessel in Kerbin orbit and KER faithfully reported 3800 dV or so fully fuelled.

AND I DIDN'T NOTICE IT UNTIL I RAN OUT OF FUEL !!!

[chengong]

@gm537: Just to be clear, this doesn't mean that everything goes. I won't care about an inch or ten, but at some point I'll just refer to the circle rule and that's that.

Eve itself can hardly be done without asparagus (1); but asparagus-ad-infinitum is the easy way out -- single launch, no worries, no finesse required. As long as rocket+tank+decoupler have a TWR > 1, you can move anything to everywhere if you just repeat the same pattern often enough. I don't think there's any point in trying to prevent it from the outset, and besides, it wouldn't be fair: I made a lot of fuss about letting people play the way they like, and if theirs is the way of the Huge Asparagus Single Launch, then by all means.... The circle rule is supposed to at least put a limit to it and/or force some sort of compromise.

(1) a serial-staged Eve lifter is technically possible, but I don't think you have many design choices. And good luck devising a landing gear.

lol all your top entries are asparagus-ad-infinitum, and at 700~900 parts they are hardly fair for ppl with low specs.

[Jason Patterson]

lol all your top entries are asparagus-ad-infinitum, and at 700~900 parts they are hardly fair for ppl with low specs.

It is entirely possible to build an Eve return vehicle that is not a huge, bloated monster. It's just a lot easier to build one that is. I can't find the challenge thread (it may have been eaten by the forum crash a couple of years ago) but one of the "Lightest Eve Return Vehicle" type missions wound up well under 200 tons, and that isn't going to be a 700 part mission. It's still asparagus, but it doesn't have to be enormous.

There and back using only 0.18.3 demo parts. (It was about an hour from launch to orbit on my old computer.) Exactly the type of vessel I'm saying not to build.

(*Note: The linked video was not intended to be any sort of submission to this challenge, just a goofy video.)

[von Ziegendorf]

Hey, I went to Eve only once in 0.18. It was an interplanetary expedition - I sent empty lander to Eve alone, then two tankers to refuel it in Eve orbit and a return ship with two Kerbals. The lander on the surface weighted 150 tons. I landed in a crater 555m above sea level. The lander (in theory) was able to ascent from 0m so I just descended from orbit without any targetting. Those time I played without any mods. The lander itself was almost flawless - only the last two stages should be made in a different way.

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[chengong]

It is entirely possible to build an Eve return vehicle that is not a huge, bloated monster. It's just a lot easier to build one that is. I can't find the challenge thread (it may have been eaten by the forum crash a couple of years ago) but one of the "Lightest Eve Return Vehicle" type missions wound up well under 200 tons, and that isn't going to be a 700 part mission. It's still asparagus, but it doesn't have to be enormous.

There and back using only 0.18.3 demo parts. (It was about an hour from launch to orbit on my old computer.) Exactly the type of vessel I'm saying not to build.

(*Note: The linked video was not intended to be any sort of submission to this challenge, just a goofy video.)

I'm just saying, if you didn't want asparagus-ad-infinitum and who-has-the-best-specs-or-least-life contest, should've made rules to directly address that, not an obviously ineffective rule that only serves to limit creativity.

Couldn't you have limited the number of non-vertical stages, per vertical stage? Couldn't you have made a scoring system based on mass and part count?

[Laie]

one question:

there is this rule "there have to be pods/hitchhikers for all Kerbals involved. No seat-only lifters."

What if there is no Pod for the Crew... but no seat either? And if they are 'inside' something? (aghhm..cargo bay...)?

Nope.

lol all your top entries are asparagus-ad-infinitum, and at 700~900 parts they are hardly fair for ppl with low specs.

Yes, I noticed. So far, my own mission is the only one to utilize a serious degree of orbital docking, refueling and the likes. Norcalplanner at least refueled in space, anyone else just went with a single launch. That was not what I had in mind, but that's how it worked out. And I'm not gonna change the rules with a dozen-odd missions already done. Besides, I'm trying to not make people play in a certain way (the stockish lifter requirement is already a big demand); as it seems, hardly anyone will bother with docking and refueling if they don't have to.

However, several of these entries can still serve as inspiration if you're looking for low part count. Especially the landers of Astrobond and Zipmafia look as if they weren't all that part-heavy (I guess you could remove half of Astrobond's struts without compromising the vessel).

In order to launch it from Kerbin, Astrobond is using a 200-part recoverable SSTO with lots of intakes and parachutes. I'm sure one could make do with a much simpler throw-away rocket. I'd also recommend to split the mission: one launch for the Eve lifter only, the other is bringing the crew, return vessel, and any rovers, gliders and whatnot you may want to use. And of course, refueling in orbit rather than taking it all up in one go. It's certainly possible to have no more than 200 parts loaded and active at any given time.

@James Eh: no savegame from when your were still in Eve's orbit? 3500m/s would be plenty if you wait for a launch window.

Edited December 6, 2014 by Laie

[astrobond]

...(I guess you could remove half of Astrobond's struts without compromising the vessel)...

Ahem... lol... yes you'r right, i'm trying to use a lot less struts in my new crafts, and the ships don't explode !!!

[kahlzun]

I'm trying this. I managed an eve return craft previously, but that relied heavily on Hooligan Labs' airship parts to get past the lower soup.

So far my best ascent has been to about 27km, will update as I get closer to shinyness

[bitslizer]

Success, I think i'm applying to the level 3 entry, version 0.25

Pretty much stock + MechJeb + Kerbal Alarm + Kerbal Engr.

Upfront note, I was using MechJeb autopilot. My reasoning, I can already do everything manually that's done by MechJeb on this event, and my time is extremely limited and I cannot sit around doing those long burns or lagging ascent.

What's not shown, lots of craft getting eaten by the kranken.... Hyperedit to Eve for simulation/testing (not its EVE lander 18... as in 18 design failures prior to this one, i had one version that would lift perfectly until the final 4 stage and then it would shake itself apart for some reason.... and struct didn't help)

Yes I researched other people's entry and took inspiration from them, I tried not to copy and paste and see if I can improve upon them. If you see aspect of your own design in my design please take it as a compliment

My goal was originally to design/test/simulate something in sandbox that I can use in my career mode save (that's why the lander was designed with Material Bay and GOO pods). However this challenge end up taking alot more time then I expected and I'll probably be taking a short break before I re-perform the mission in career mode.

I ended up taking the LKO orbital refuel approach... could I have gone with single Launch? probably, but by the time I tested my Kerbin lifter to make sure I can launch the lander fully fueled. My wife was nagging me to stop playing KSP so I decide to just refuel the sucker in orbit with the same lifter rather than spending additional time re-desiging a lifter that can do single launch... is it the most efficient/least fund design? hardly even close.... but it... got the job done!

funds

unfueled lander+ lifter/interplantery stage = 701,850

orbital fueler x2 = 467,860x2 (i believe 2 refueling trips would have top up the lander and interplanetary stage)

kerbin lander = 16,973

The mission would probably have been cheaper if i decide to recover the orbital refueler, but I'm time constrained and this was done in sandbox mode anyway

Parts count

lander + lifter = 492

eve lander only (no chutes and landing gear, just whatever boost to eve orbit) = 209

Eve lander only weights 204,160kg (without chutes and landing gears)

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Edited December 9, 2014 by bitslizer

[Laie]

Upfront note, I was using MechJeb autopilot. My reasoning, [...]

Nevermind. Though I dare you to try without for a while -- I find that I'm pretty ***ed up without smart a.s.s. My landings would need much more delta-V without it. And while I prefer to plan the more complicated maneuvers myself, I'd be lost if I had to do it with the stock pull-thingy. Being able to edit the node while being fully zoomed in to the destination is priceless.

Looking through your delta-V stats, you've got about 330 seconds at an average TWR of 1.35 to take you out of the atmosphere... that's insanely tight. I once had a craft like that myself and had to start over and over and over.... but yes, it can be done. Your lifter looks familiar, but I guess that's only because Eve is funneling everyone towards similar solutions. I like it that you took the time to attach some science gear, and how your clock turns green during the ascent

Congratulations, You've completed the Eve Rocks Challenge on level 3!

[2001kraft]

Can I ask a question about the circle in VAB rule?

I am going to make a huge Blended-Wing-Body-ion-powered-Single-Stage-To-Eve-spaceplane....

Are there any size restrictions for the SPH? Or I'm not even allowed to build there due to the same size restriction rule.

I'm super sure that this is possible and I will not give up until I make this thing fly in Eve and out of it. Thanks and sorry for being persistent

[Red Iron Crown]

Can I ask a question about the circle in VAB rule?

I am going to make a huge Blended-Wing-Body-ion-powered-Single-Stage-To-Eve-spaceplane....

Are there any size restrictions for the SPH? Or I'm not even allowed to build there due to the same size restriction rule.

I'm super sure that this is possible and I will not give up until I make this thing fly in Eve and out of it. Thanks and sorry for being persistent

If you can get to Eve orbit from the surface in a single stage that would be an accomplishment worthy of its own thread. It is generally believed to be impossible as it is just barely possible from Kerbin, the first to do so will become a KSP god. Good luck.

Edit for below: Good point, Overfloater. Success is likely to be met with suspicion and accusation.

Edited December 9, 2014 by Red Iron Crown

[Overfloater]

...the first to do so will become a KSP god....

Nah, whoever succeeds will be accused of infini-gliding for using a controllable aeroplane.

Srsly whatever i put on Eve shakes like crazy, and amount of flaps was minimal.

[bitslizer]

Nevermind. Though I dare you to try without for a while -- I find that I'm pretty ***ed up without smart a.s.s. My landings would need much more delta-V without it. And while I prefer to plan the more complicated maneuvers myself, I'd be lost if I had to do it with the stock pull-thingy. Being able to edit the node while being fully zoomed in to the destination is priceless.

Looking through your delta-V stats, you've got about 330 seconds at an average TWR of 1.35 to take you out of the atmosphere... that's insanely tight. I once had a craft like that myself and had to start over and over and over.... but yes, it can be done. Your lifter looks familiar, but I guess that's only because Eve is funneling everyone towards similar solutions. I like it that you took the time to attach some science gear, and how your clock turns green during the ascent

Congratulations, You've completed the Eve Rocks Challenge on level 3!

Thanks!

Definitely agree....

I would not have a problem with landing as I'm doing unpower landing, as long as I maintain retrograde through out the entire process if i'm doing manual landing, the drag would hold me in the right position for the landing in the end. EVEN if i flip upside down, I can manually deploy chutes to selectively increase drag which would right side up the lander.

Ascent without the autopilot WILL BE much tougher, but just seeing MechJeb does it once or twice you get a feel of the timing and turn profile, and that already help alot.

Frankly for the meetup and docking, I feel MechJeb waste more DV than If i do it manually, but I was lazy and have more than enough DV fuel budget to let it fly for me while I'm working on something else (i play ksp in window mode).

As to the lander looking familiar, yes it is the common FT400+FT800+Aerospike build... In the first pic you can see my attempted at a wide footprint lander build that I typically prefer, while that thing can make orbit from sealevel, the DV budget is even tighter and the parts count even higher and lagging like crazy on my computer. Originally my thoughts were to do a high TWR approach to get up to 30K ASAP with each stage being optimized to the terminal velocity on EVE by adding stage specific fuel load that's why there are all the odd size tanks. My approach was to have a common core using the fat/flat tank with 8x Jr docking port in symetery mode + 8x 48-7s + 1 centrally mounted 48-7s, but each core section already end up having a partcount of 18.... using that for asparagus staging and that quickly bog down the system (vs 3 with the FT400+FT800+Aerospike).

So I went back to the drawing board and after some research and turn out the Aerospike build is the best compromise between DV, TWR and parts count for my rig (I5-2500k + 8GB + GTX660 TI)

as the the DV being tight... well this thing still seem plenty of leg left to it, the TWR creeps up with each stage while the DV boost get lower, so it seems I can actually add at least another 7x stages (each stage being FT400+FT800+Aerospike x2) before adding more stage add little if any DV... 8x stages would have been another 2 full onion rings and probably still fit within the VAB circle rule so If i end up having to do a sloppy ineffeicient manual eve ascent that's a brute force approach that would add at least another 1000 atmosphere DV.

In fact let me toy with that tonight to see what's the break even point.... but that's definitely kind of the asparagus ad infinium thing.....

Lastly what did you meant by being able to edit node while fully zoomed in? I thought that was a stock KSP feature that mechjeb just take the hassle out of finding the semi-optimal point to place the node

[Laie]

as the the DV being tight... well this thing still seem plenty of leg left to it, the TWR creeps up with each stage while the DV boost get lower,

Have you considered removing one set of FT400s from the innermost stage? The higher TWR might make it worthwhile.

Lastly what did you meant by being able to edit node while fully zoomed in? I thought that was a stock KSP feature that mechjeb just take the hassle out of finding the semi-optimal point to place the node

Getting both the node and the destination on the screen at the same time can be quite tricky. And god forbid the node should decide to close itself, then you have to move back top open it, then find your viewpoint again... the MJ node editor does away with all of that.

[bitslizer]

Have you considered removing one set of FT400s from the innermost stage? The higher TWR might make it worthwhile.

Getting both the node and the destination on the screen at the same time can be quite tricky. And god forbid the node should decide to close itself, then you have to move back top open it, then find your viewpoint again... the MJ node editor does away with all of that.

its possible... I can toy around with it

I hardly EVER use the node editor... mostly i have MechJeb manuver planner to create the node, focus view on the destination (which does show me the predicted path along with PE) spin camera to find the node and use the push pull thingy and mouse wheel to adjust the node as necessary (ie adjust the PE for aerobraking or the insertion inclination). The only time I would use the node editor where I can actually input the numbers is if I need to make super tiny adjustment that even the mouse wheel give too much/inaccurate change and I hardly ever run into that problem.

For sure I did not use mechJeb node editor for this challenge