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[1.7-1.9] SMURFF: Simple Module adjUstments for Real-ish Fuel-mass Fractions 1.9.1 (02019 Nov 12)


Kerbas_ad_astra

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On 2/22/2017 at 2:14 PM, brygun said:

Hello,

Im new to trying out this mod and have some basic questions. CKAN is being used as a mod manager. First general discussion on why Im trying SMURFF

Im not using Real Fuels largely due to the engine restarts and ullage. For engine restarts I like reusable explorers which they often trouble. An EVA Kerbal engineer could replace the 'matches' or other starters but Im not aware of that being coded yet. The ullage is a relatively minor issue solved by having solid rockets fire for a few seconds before starting the engine. The game code though requires an extra stage or manual vs Mech Jeb auto staging. With larger and certainly complex explorers having to give up potentially several stages is actually a problem. SMURFF seems to provide the more real ISP, engines and tanks without those issues. Hoping it goes well.

My questions are more about views on if these are the right mods and if Im missing any. If got lots of mods installed, like MechJeb and so on, so this is more about mods giving parts.

Real Solar System is being used

USI for a decent yet playable life support mod has been selected.

SpaceY is installed

I was using KW Rocketry in a recent play. I'm wondering if it is reasonably close to this mod so I might copy over those craft.

Near Future various are installed as well.

 

Are there other mods I should consider?

Are there other mods to avoid?

I don't use KW rocketry myself (though if it's balanced like stock parts then SMURFF will handle it just fine), but the others I do use and like (and to some extent support with SMURFF -- e.g. Near Future's lithium and argon fuel tanks).

For your consideration, I'd suggest looking at HGR or MOLE, for 1.875m parts.  The jump from 1.25 to 2.5m parts is pretty steep, and it's nice to have an intermediate size.  For RSS in particular, I've found size "1.5" parts are great for launching small payloads into orbit without producing excessively long rocket noodles (being squatter than size 1).  Here's a rocket I've made for landing a seismometer (from the Impact! mod) on the Moon:

Spoiler

SeismometerLander.png

 

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On 1/3/2017 at 4:21 PM, Zuthal said:

What would be the proper way of determining what lever is the right one for a certain system scale? I was assuming that the mass ratio multiplier relative to stock is proportional to the lever, and that levers=1 is balanced for RSS.

Then, the lever for a certain scale, I would htink, to maintain roughly the same difficulty, should I think be proportional to the ratio of the mass ratios you need to LKO in the different scales, which would give ~0.56 for the levers for 64k if you use engines with an exhaust velocity of 3500 m/s.

Is that anywhere close to sensible?

Zuthal,

I'm not sure anyone ever responded to this, so I'll take a crack at it.  My rule of thumb is around 0.25 or 0.3 lever for 3.2x, and 0.5 or 0.6 for 6.4x.  Your proposed 0.56 lever for 64K seems right on the money to me.

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  • 3 weeks later...

First off thanks so much for this amazing mod.  I noticed that the 10m inflatable heat shield is not being scaled like the other heat shields - the other shields are all registering at 50% unmodded weight as per your description, but that new heat shield is still at it's stock weight of 1.5t.  The new 10m part has its own space in the squad\parts directory (InflatableHeatShield) where all the others are in the plain old HeatShield directory, which is perhaps why it's being treated differently.

Not sure if intentional or not, but thought you'd like to know.

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SMURFF doesn't work by part names; it works based on the resources and modules that a part has.  The inflatable heat shield doesn't use the same ablative heat shield material or module that the others do, so the patch doesn't apply.  (Nor should it -- the LDSD was 5 meters wide and weighed 3 tons, though much of that was surely taken up by the motor assembly.)

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It seems Kerbalism adds monoprop to kerbals on EVA, so SMURFF is trying to adjust them like a fuel tank, which is kinda funny.   Is there a way to blacklist the KerbalEVA and KerbalEVAfemale parts so SMURFF will ignore them?

[LOG 05:53:27.411] [ModuleManager] Applying node SMURFF/SMURFF/@PART[*]:HAS[@RESOURCE[MonoPropellant],~SMURFFExclude[*rue]]:FOR[zzz_SMURFF] to Squad/Parts/Prebuilt/kerbalEVA/kerbalEVA
[LOG 05:53:27.413] [ModuleManager] Cannot find key mass in PART
[LOG 05:53:27.413] [ModuleManager] Error - Cannot parse variable search when replacing (%) key initialmass = #$mass$
[LOG 05:53:27.414] [ModuleManager] Applying node SMURFF/SMURFF/@PART[*]:HAS[@RESOURCE[MonoPropellant],~SMURFFExclude[*rue]]:FOR[zzz_SMURFF] to Squad/Parts/Prebuilt/kerbalEVAfemale/kerbalEVAfemale
[LOG 05:53:27.415] [ModuleManager] Cannot find key mass in PART
[LOG 05:53:27.416] [ModuleManager] Error - Cannot parse variable search when replacing (%) key initialmass = #$mass$

 

Edited by eberkain
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2 hours ago, eberkain said:

It seems Kerbalism adds monoprop to kerbals on EVA, so SMURFF is trying to adjust them like a fuel tank, which is kinda funny.   Is there a way to blacklist the KerbalEVA and KerbalEVAfemale parts so SMURFF will ignore them?

Setting SMURFFExclude on the part is the usual way.

@PART[Whatever]:NEEDS[SMURFF]
{
    %SMURFFExclude = true
}

 

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  • 3 weeks later...

It surely 'works with' Interstellar in the sense that they don't conflict, but I don't use Interstellar myself, and as it adds lots of resources to the game (and, judging by the pull requests I see on the Community Resource Pack, it is always adding more resources), supporting Interstellar would require more effort than I'm able to sustain.

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  • 3 weeks later...

Hey just a quick note.  In your main post, you mention that the choice between xenon/argon comes down to cost. I really doubt that's the case, realistically, fuel costs for rockets are really a low percentage, especially when you're talking about final stages.

Instead, it's about the tradeoff between ISP and thrust.   Scott Manley has a good video about it here, but the TLDW version is 'xenon gives better thrust, lighter noble gases give better ISP, but when you're dealing with ion thrusters, the ISP is already good and the thrust is abysmal'

 

 

 

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Putting together an RSS install from scratch and I'd really like to include SMURFF, so the questions:

Does SMURFF play nice with SETI -- Unmanned before Manned? and

Is there any issue with also running KSP Interstellar Extended?

Thanks for a super great mod btw.

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  • 3 weeks later...
10 hours ago, The-Doctor said:

@Kerbas_ad_astra Hey, I'm getting a few issues with the mod, in that, it doesn't get me to orbit in RSS, I thought that's what it would do, scale up the power of the engines so that you can play RSS with stock engines right? Just curious, I'm really interested in playing RSS with stock engines.

SMURFF adjust stock parts to have performance more like real rocket parts.  However, this does not mean that a stock rocket that can reach orbit around Kerbin can reach orbit around Earth with SMURFF.  Because of the logarithm in the rocket equation, even a 4x reduction in rocket dry mass (which is more-or-less what SMURFF does) has pretty strongly diminished returns (a 60% increase in delta-V capacity at maximum, but more like 40% in practice because there's more to a rocket than engines and fuel tanks), while the delta-V requirements to get around the solar system roughly triple.

For a concrete example, it is possible (barely) to get into orbit with RSS and SMURFF by taking a Kerbal X, removing the ladder and legs, and doubling the upper stage fuel tank.  It has just over 9500 m/s of delta-V.  In stock, the same rocket has "only" 6800 m/s of delta-V, which is enough to land on Duna and return (with very careful piloting and exploiting aerobraking opportunities to their fullest).

So, while SMURFF makes it easier to get into orbit (or anywhere else) in RSS, it is still much more challenging than in stock.

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10 hours ago, The-Doctor said:

@Kerbas_ad_astra Hey, I'm getting a few issues with the mod, in that, it doesn't get me to orbit in RSS, I thought that's what it would do, scale up the power of the engines so that you can play RSS with stock engines right? Just curious, I'm really interested in playing RSS with stock engines.

As an add-on to what the mod author said, vehicles are lighter and LFO engines have 50% more thrust, so if you don't change the amount if fuel carried, your TWR will go through the roof. SMURFF allows you to increase tankage across all your stages, while maintaining TWR and gaining a lot more delta v in the process.

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  • 2 weeks later...
On 5/22/2017 at 5:25 PM, The-Doctor said:

@Kerbas_ad_astra @Norcalplanner I checked the first page and saw the ways to edit it, I changed them all from 1 to 2, so now I can comfortably enter Earth orbit with just about all stock rockets without any modificcations

I hope you didn't set podLever to 2!  Your pods will be practically weightless, have no reaction wheel authority, and your heatshields will have zero ablator.

On 5/29/2017 at 11:21 AM, rohanguard1 said:

@Kerbas_ad_astraHey, FASA was Just released for modern Kerbal Space Program. Can you make SMURFF compatible with it, because right now, the rockets are a little underpowered.

SMURFF should be compatible with any mod that uses stock resources and more-or-less matches stock balance.  Have you tried using it with FASA?

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1 minute ago, Kerbas_ad_astra said:

SMURFF should be compatible with any mod that uses stock resources and more-or-less matches stock balance.  Have you tried using it with FASA?

I have tried using it with FASA, and it is horribly unbalanced. If you try out some of the rockets, they have nowhere near the mass fractions they should have. Ex: The Explorer probe only has 4,000 m/s of Delta V, when it should have 9,500

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13 minutes ago, Kerbas_ad_astra said:

I hope you didn't set podLever to 2!  Your pods will be practically weightless, have no reaction wheel authority, and your heatshields will have zero ablator.

SMURFF should be compatible with any mod that uses stock resources and more-or-less matches stock balance.  Have you tried using it with FASA?

not podleveler, anyways, I'm looking at either SSRSS or stock for my next career

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1 hour ago, rohanguard1 said:

I have tried using it with FASA, and it is horribly unbalanced. If you try out some of the rockets, they have nowhere near the mass fractions they should have. Ex: The Explorer probe only has 4,000 m/s of Delta V, when it should have 9,500

Where are you getting FASA?  All I'm finding is releases for KSP 1.0.x.

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Looking at those parts, I see that they're not balanced like stock parts.  Most of them are lighter, but that means that SMURFF won't act on them at all (if SMURFF's changes would make a part's mass negative, it won't act on that part).  You can try setting the tankLever to be less than 1, but then parts that are balanced against stock won't be as effective.

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