Intermediate resources

[Pthigrivi]

I think its interesting that they've opted to define LFO as methalox, but it also got me wondering about how the real chemistry of ISRU might me abstracted in the game.  Im definitely in the camp that realism is great, but only if it makes a game more fun. But often in KSP there are instances when a simplified model of hard-scientific reality does just that. Could managing off-world resources fit into that camp?

Lets look a moment at the kind of resources we might find on other bodies:

H2O
CO2
O2 (bound up in rock)
Metals (Al, Fe, Mg) 
Xenon (extracted from atmo)
Uranium
He3

From those you can create most of the things we'll need:

CH4 + O2 (methalox)
Life support: (O2, H2O, Carbohydrates)
Monoprop: (H2O2)
H2 
Rocket + colony parts
Ion propellant
Nuclear fuel
Fission fuel

I think for simplicity it makes a lot of sense to get as much milage out of a generic, harvestable "Ore" resource for most of the mid-game and using the various fuel factories to convert that supply into usable resources. Technically carbon is hard to come by on the moon and many bodies, but we could probably pretend the Mun and Minmus are more cabonaceous to keep early ISRU simple. The question I have is should it be possible to convert methalox into life support? or H2 or monoprop? It was certainly a fun dynamic in the Martian and could produce some interesting strategies. The other question is how many resources should go into making parts? We've seen in an early screen-cap that some parts use ore and uranium, but does it make sense to have more than that? Does it help or hurt to have intermediate resources like metals or polymers? I've played around with MKS and found it fun, but probably much more complicated than KSP2 wants to be. But it could be that water ice and atmospheric CO2 could be harvestable resources from which you could easily produce fuel and LS but not new rocket parts?

The big thing for me would be seeing how the availability of different resources guides the way players strategize their colony development and trade. I think its important that there aren't places where you could set up one colony that produced everything. There should be locations where ore is more concentrated but there's little Uranium or science to be mined, that you'd have to set up in multiple locations and cleverly ship key resources around. Does it make sense that Ore could be refined into an intermediate resource so it could be shipped to orbit or other colonies more easily? If you're setting up a resource chain does it make it easier if you can just ship methalox fuel somewhere and then convert that into other things like LS and Monoprop?

Edited April 19, 2021 by Pthigrivi

[PlutoISaPlanet]

I absolutely agree that to get certain resources you should have a different colony or outpost.

[shdwlrd]

Well, I would like ore to stick around for a generic construction material. It could easily encompass both metals and regolith. 

Fuels and LS on the other hand, could get fairly complicated. My only real hope is they don't make it too complicated. I would really prefer one raw resource equals one final product. But for some reason I don't see that happening. As long as there isn't too many intermediary products between the raw resources and finished product, it shouldn't be too bad. I just hope they don't pull a MKS and USI-LS with changing the recipes and not documenting the changes that were made. (This is the primary reason I stopped using the USI resources and just use the parts now.)

For shipping and trade strategies, that would be up to the individual.

[Pthigrivi]

So off the top of my head without breaking carbon out:

Kerbin: Ore, U, Xenon
Mun: Ore, He3
Minmus: Ore
Moho: Ore, He3, U
Eve: Ore, Xenon, U
Gilly: Ore, U
Duna: Ore, U
Ike: Ore, He3
Dres: Ore, U
Jool: Xenon
Laythe: Ore, Xenon
Val: Ore, U
Tylo: Ore, U, He3
Bop: He3
Pol: Ore, U

Which could be balanced further by varying the quantities of each resource and how difficult it is to reach, (say by having rich ore deposits only at poles or U only available in deep craters). I think it would also be nice if most necessary resources could be found within a planets' system so you weren't dependent on too many interplanetary transfers that take a long time. Now you could also add in ice + CO2 as harvestable resources, or make Ore inherently low-carbon and have carbonate as a harvestable resource that could be combined with Ore to produce LS, polymers and and Methalox, but the more I think about it this probably makes things more complicated than they need to be. I think you want to be able to flip back between different resource overlays to find the best base locations, but you don't want those intersections so rare that there's really only one place to build. I still think it might be nice to make "Metals" an intermediate resource derived from ore that you could make into parts so that you could ship just that fraction to orbital shipyards. 

The question is how might local resource scarcity drive different overall strategies? It probably wont be difficult to get access to Methalox, LS, Monoprop, and H2 through Ore. Uranium will probably be important for power generation, rocket parts, and fuel for Orion and NERVA engines. So you can do a lot with just those 2 resources. Maybe however there's an alternate strategy in which you invest in Xenon engines, set up a refinery in orbit above Eve, then leverage that to expand to Jool and Laythe? Or maybe instead you set up a robust Duna base using NERVAs, and then eventually start mining He3 and using fusion power to produce metallic hydrogen on Ike? Those are the kinds of grand strategic choices that really interest me, and could totally shift the way you planned out fleets of high-ISP tugs or big interplanetary freighters or strategically placed orbital shipyards. 
 

Edited April 19, 2021 by Pthigrivi

[shdwlrd]

I can see Kerbin having all the resources available because of a large (if not apparent) manufacturing base. The only limiting factor would be the availability and time to ship them. At a certain point, I can see having to wait for resources to be available to ship. That should push the need for colonies to start collecting on their own.

I've never got as detailed as to which planets would have which resources. I'll leave that to the devs.

For logistics, I can see mirroring what happens in the real world for transferring the resources around.

[Pthigrivi]

@shdwlrd Haha yeah, I mean these are just a for-instance. Obviously there's a lot going on we don't know about and 2 whole engine types we haven't seen. It's the principle I think that's important, what level of resource management is fun and what becomes a bear, thinking through progression not just as a series of landing challenges but as an overall resource exploitation puzzle. 

Edited April 19, 2021 by Pthigrivi

[K^2]

I like the idea of collecting a mixture of resources to be converted into fuels and other resources, but I would much rather keep things simple as far as specific chemistry goes.

In the real world, just in common use for liquid fuels alone are kerosene, methane, several different blends of hydrazine, and liquid hydrogen for fuel, which can be mixed with almost any of the common oxidizers, albeit, some to better effect than others, among liquid oxygen, nitrous oxide, and hydrogen peroxide. And just to make things more exciting the two most common monopropellants are hydrazine and hydrogen peroxide, which come from two different categories of the above.

KSP keeping it down to just "liquid fuel" and "liquid oxidizer" was the right call. At least, until you start thinking about NTR propulsion, because you aren't going to run an efficient NTR on kerosene, and jet planes are going to have to have much bigger tanks if they are running on hydrogen.

With addition of fusion, I think, calling out hydrogen explicitly is the way to go. I would, therefore, limit the liquid fuels to "Liquid Fuel," which is some unspecified hydrocarbon, "Liquid Hydrogen," says it on the tin, and "Monopropellant," which I would argue should be more hydrazine inspired. For starters, I think it would be interesting to have an option to burn monopropellant with oxidizer in some engine types, and have a unified fuel tank for both your main engines and RCS.

And if we don't need hydrogen peroxide for oxidizer, I'm pretty happy just having "Liquid Oxidizer," and model it after liquid oxygen. If life support is, indeed, part of stock, I would be perfectly happy with it being one of the consumables for that system as well. I don't think it has to be explicitly called out as oxygen either way.

In terms of raw resources, this does play nicely with just keeping most minerals under umbrella of "ores", which can provide metals for construction and SRBs as well as byproduct oxygen. Now, I'm not aware of any process that even attempts to reclaim oxygen in ore refining, but then again, why would you try on Earth? I'm sure that various arc methods will produce plenty of oxygen gas as a byproduct that will have to be captured and extracted. But what I would then add is water ice and ammonia ice. The later being used to replace atmospheric nitrogen if you want to subsist on asteroid mining.

This does still leave a lot of chemistry, but now, I think, it can be hidden under the hood for casual player. For example, lets say you are setting up the gas condenser on Duna. What we have going into it is mostly CO2 and what we want to be getting out is methane and oxygen. Without getting into details, the UI for the condenser can simply show: "Oxidizer: +X units/minute, Liquid Fuel: +Y units/minute, Hydrogen: -Z units/minute." The negative water production tells you that you need to hook up a hydrogen storage tank and some way of filling it up if you want to have the condenser do anything. Whereas, same unit sitting on Kerbin might tell you something like, "Oxidizer: +X units per minute. Optional: Monopropellant: +Y units per minute, Hydrogen: -Z units per minute." So if you just need oxygen, it will do perfectly fine on its own, but if you want to make use of nitrogen as well, then you'll need to provide a source of hydrogen.

For people who want to crunch out the numbers, all the stoichiometry can be provided either somewhere deep within the game or on Wiki. And for anyone who wants to just figure things out live, the UI provides most of the information they need to make it work, possibly, via some iteration.

[shdwlrd]

1 hour ago, Pthigrivi said:

@shdwlrd Haha yeah, I mean these are just a for-instance. Obviously there's a lot going on we don't know about and 2 whole engine types we haven't seen. It's the principle I think that's important, what level of resource management is fun and what becomes a bear, thinking through progression not just as a series of landing challenges but as an overall resource exploitation puzzle. 

I agree and understand. With the large resource base that is coming to KSP2, it's hard for me to speculate that deeply into it without a vested interest. Without knowing the raw resources and final products. I can see right now is a very general image of what's going to happen logistically.

In the early game, you're going to be stuck with doing Hoffmann transfers which would limit the early trade to Kerbin's and Jool's SOI based on how quickly you can traverse between the planets and moons. But trade between Kerbin and Jool will be sporadic because of optimal transfer windows. (All the other planets would suffer from the same problem more or less.) That means any resources collected will be used for local production or stored for transfer to other planets. Once you can start to brute force brachistochrone transfers, different routes will begin to open up. Probably limited to urgent supplies in the beginning. Once you get engines that can do brachistochrone transfers reliably and cheaply there would be very little limitations on trade within the star system. Which at that point, you're looking to start going interstellar.

[mattinoz]

Curious as to why Water doesn't get a mention as a resource.   Surely the resource system will cover more than fuel for engines and extend to keep Kerbals alive and thriving.

Would be nice to see distinct levels of mining a drill might get ore and water if sunk into ice or a lake.  Special resources should present a distinct challenge if they exist.

[KSK]

I don’t think many raw materials or intermediates are required.

Ore. For all your off world construction and SRB requirements.

Water. Helpful for keeping your Kerbals properly hydrated. Can also be processed into hydrogen and oxygen.

Carbon.  Optional. Could be an extra resource for high tech materials. Can be combined with oxygen into carbon dioxide.

Carbon dioxide. Can be extracted directly as a raw material or manufactured as mentioned above.

Nitrogen.

Manufacturing then goes as follows.

Hydrogen + carbon dioxide = Liquid Fuel plus Liquid Oxidiser.

Oxygen = liquid Oxidiser.

Nitrogen plus Hydrogen = Monoprop. 
 

That also gives you oxygen, water, and fertiliser (nitrogen plus hydrogen again) as inputs for any life support systems.

Water is found pretty much everywhere from permanently shadowed craters on Moho or the Mun, to the ice caps of Duna, to the muns of Jool.

Ore is found everywhere.

Carbon is found on Kerbin, possibly Laythe, and has a chance to occur in asteroids.

Carbon Dioxide is found in planetary atmospheres, the Dunan ice caps and the smaller muns of Jool which are assumed to be icy bodies.

Nitrogen is found in planetary atmospheres. 

Progression-wise, you start with access to all raw materials on Kerbin. Water is easy to find in the Kerbin system so your initial off-world manufacturing efforts probably focus on Water and Oxygen for partial life support, plus fuel and oxidiser for hydrolox and/or nuclear engines. If you’re able to capture a suitable asteroid then Carbon comes into play too, giving you access to LFO.

Going further afield to Duna, you now have access to Water, Carbon Dioxide and possibly nitrogen, although I’d be inclined not to make nitrogen available. That gives you guaranteed access to Water, Oxygen, Liquid Oxidiser and LFO (if you weren’t lucky enough to find a suitable asteroid.

Going still further afield to Laythe, you get access to Nitrogen too which means that you can manufacture everything off-world if you so wish.

Edit. If you want a little more realism then make oxygen a raw material for monoprop (needed for nitrogen tetroxide or nitric acid) and fertiliser (needed for nitrates). That won’t have a significant impact on gameplay and is largely realism window dressing if you want the chemistry to look more plausible.

Edit 2. If I’m adding this up correctly, the above scheme has four raw materials (carbon, water, nitrogen, carbon dioxide), two intermediates (oxygen, hydrogen) produced from the same raw material, one manufacturable raw material (carbon dioxide), and three manufactured resources (Liquid Fuel, Monoprop and Fertiliser).

Combine them all and that’s everything required for moderately realistic but fully featured propellant and life-support resource system.

Ore kind of sits off to one side as a generic building resource.

That doesnt seem excessively complicated to me but YMMV.

Edited April 20, 2021 by KSK

[PlutoISaPlanet]

I just realized, minmus will probably have better resources then the mun.

[Pthigrivi]

@KSK Love this. I feel like there's some elegant sweet spot between a robust organization like yours and what @K^2 suggests. There are two parts to streamlining, making something understandable so players aren't wasting time making big mistakes, and condensing things so there aren't so many variables and parts to worry about. For instance if some element of chemistry can happen inside a converter and doesn't need to be transported then that element can be kept under the hood and doesn't need its own in-game resource or tanks. Fortunately the only intermediate resources in your scheme are O2 and H2 which will probably have their own tanks anyway. I also really like the idea that a colony that was lacking a resource could be supplemented by capturing an asteroid--always a fun challenge. The other handy thing is this is a toy solar system and we can kind of make up whatever surface composition we want, but its always nice if it maps on to the real solar system. 

What I think matters quite a bit gameplay-wise is how prospecting works. Say you had a surface spectrometer part that you could put in orbit and get an overlay of where different elements were most common. When selecting your colony location you're going to want a spot that has as much of what you need as possible. To keep things fun early on you're certainly going to need a source for some basics--Methalox, Monoprop, + LS. So thats at the very least some source of carbon and ice, maybe nitrogen. Later as you start phase 2 building new components and rockets on site you'll need metals from Ore and Uranium. If all these were represented in a scan you'd be looking at 5 different harvestable resources, and looking for areas with as much coverage as possible. I think this is probably too many. For the sake of simplicity you could say all ore has enough metal in it to be suitable making parts, and what you're really looking for are areas that are high in water ice. You could probably also for simplicity pretend we were using H2O2 rather than Hydrazine and pretend away nitrogen in LS. That would get us down to 3 scannable resources--H20, Carbon (either mined chondrites or CO2), and Uranium. That might not be so cumbersome to find in combination. If you were breaking out carbon it might also make sense that most parts were just a combination of metals and plastics and that only a few advanced parts required Uranium. Maybe his sounds overcomplicated, but you'd only need one refinery part that could process both if you have access to ice-rich ore and carbon. In either case I think ideally you want all of these available within each planets' SOI so you'd have the option to build and expand one main base either on the surface or in orbit and feed it with outposts gathering whatever it lacks. 

--Or you could break it up a different way--to assume all ore contains sufficient carbon and a high Ore concentration means its rich with metals, but there's a separate scan for ice that lets you mine and combine to produce fuel and LS? At that point though you may as well stick to a single "ore" resource, and a high reading means its got high values of everything except Uranium and other exotic resources. 
 

2 hours ago, PlutoISaPlanet said:

I just realized, minmus will probably have better resources then the mun.

Why do you think? I imagine it would work out if it was an easier early-game location, but to get later game resources like He3 you'd have to fight Mun's higher gravity. 

Edited April 20, 2021 by Pthigrivi

[KSK]

I have a slightly different view on this. I wouldn’t be unduly worried about having lots of resources to harvest provided that: 

a) It’s entirely apparent what each resource does.

b) There are reasonable alternatives that the player can use so that lack of any one resource isn’t game-breaking.

c) The tech tree is flexible enough that the player can research those alternatives in a reasonable time.

Gameplay then becomes a balance between making do with what you have at a given site, founding another site to harvest the exact resources you need, or shipping in resources from a more developed site (worst case scenario, shipping it in from Kerbin which has everything).

The big trick will be making the ‘make do’ option a matter of maybe not having the perfect tools for the job but adequate.

Under my scheme, for example, it’s quite likely that nitrogen availability will be limited which, in turn, limits the player’s use of monoprop. That’s fine (IMO) provided the player can research Vernor engines, or some equivalent RCS system that runs on another propellant combo.

A more controversial example could be the Fuel that Shall Not be Named.   It only requires water to make (plus the appropriate tech of course) and makes a good (arguably better) alternative to nuclear engines if the player doesn’t have easy access to uranium.

Edit. I’m all for abstracting away most of the chemistry incidentally, so long as the raw materials that you’re chucking into your refining gear looks sort of okay.  Again, using my scheme:

1. Find nitrogen and hydrogen.

2.  ????

3. Monoprop!

I’m not even sure if the middle step corresponds to any actual chemistry - and I’m fine with that. The raw materials look approximately correct for those that care about such things and the details... well this is Kerbal Space Program, not Kerbal Chemistry Lesson.  

It would be nice if the ISRU system is plausible enough to lead the interested player to digging out the details in their own time though. I think that would fit nicely with KSP inspiring players to learn more about rocketry in their spare time.

Edited April 20, 2021 by KSK

[Pthigrivi]

8 minutes ago, KSK said:

A more controversial example could be the Fuel that Shall Not be Named.   

Im stupid today, whats that?

[KSK]

3 minutes ago, Pthigrivi said:

Im stupid today, whats that?

*looks around furtively*
 

Metallic Hydrogen.

[Pthigrivi]

2 minutes ago, KSK said:

*looks around furtively*
 

Metallic Hydrogen.

Oh of course. Yeah I figure thats latish game and probably has some huge power requirements and in practical terms you'd need fusion generators to produce?

[PlutoISaPlanet]

I assume Minmus has water. 

[KSK]

1 hour ago, Pthigrivi said:

Oh of course. Yeah I figure thats latish game and probably has some huge power requirements and in practical terms you'd need fusion generators to produce?

Midgame, I always thought (somewhere between KSP1 level chemical engines and the high end interstellar engines) but yeah, definitely not available in the early game.

In which case, a lack of off-world uranium  would prevent the player from building NERV powered ships off-world. Nothing to stop the player sending them out from Kerbin though and then refueling them pretty much anywhere though since I'm imagining water to be available almost anywhere (in varying quantities). Or that lack of uranium could be a prompt that pushes the player to beeline for MH related techs.

53 minutes ago, PlutoISaPlanet said:

I assume Minmus has water. 

You could argue either way, depending on how the developers play it and how realistic they're feeling. Minmus is difficult to explain as an icy body but the devs could handwave that away for the sake of gameplay. Water ice on the Mun would be realistic though, so hopefully that would be a thing.

[Dientus]

1 hour ago, PlutoISaPlanet said:

I assume Minmus has water. 

Curious, why would you assume that?

[PlutoISaPlanet]

49 minutes ago, Dientus said:

Curious, why would you assume that?

It appears to be frozen.

[Pthigrivi]

So we're really only talking the difference between:

Ore ----> Methane, O2, Monoprop, LS, H2, MH, Parts 
Uranium ----> Energy, Orion pellets, Parts
Xenon -----> Ion Fuel
He3 ----> Energy, Fusion Fuel

or

Ore ----> Parts
H20 ----> H2, O2, MH
H20 + C ----> Methane
H20 + N ----> Monoprop
H20 + C + N ----> LS, Parts
Uranium ----> Energy, Orion pellets, Parts
Xenon -----> Ion Fuel
He3 ----> Energy, Fusion Fuel

And maybe the latter sounds more interesting to me, but a little hard in the transition from early to mid-game cobbling together basics from scattered harvesting sites. 

[KSK]

That looks about right.

And yeah, there will be a transition to overcome but that also means that the various ISRU elements can be introduced gradually for new players.  Whilst you're still launching everything from Kerbin and doing Mun / Minmus missions, then ISRU is a bit of a gimmick frankly, since Kerbin can supply everything and is never more than a few days away.  Nevertheless, water and ore will be easily available off-world, possibly uranium and He3 too. You can't build a completely self-sufficient base on the Mun, for example but you can do quite a lot.

The first transition to overcome is finding a source of off-world carbon but that's reliably achievable by going to Duna, which is one of the next logical destinations after the Mun and Minmus. After that, the remaining transition is finding off-world nitrogen. Under my proposed scheme that required a planetary atmosphere and excluded Duna. Plenty of ways of making things easier though - adding nitrogen to Duna's atmosphere would be an obvious help.  Alternatively, you could flesh out the nitrogen manufacturing a bit by adding ammonia as an intermediate - and then making ammonia extractable from icy bodies. So you end up with one carbon intermediate (carbon dioxide) and one nitrogen intermediate (ammonia), both of which can either be synthesised or directly mined, depending what resources the player has to work with.

Admittedly, that's a little more complex, but it also makes actual gameplay a bit easier because it smooths out a significant transition in that gameplay.

Beyond that, I guess it depends what kind of game the developers have in mind. Personally, I'm not a fan of Ore as a magic 'make anything' resource, the way we have it now, and would like the game to be a bit more about  exploring to find resources and setting up the infrastructure to move them around and make use of them. To me, building that kind of benign Kerbal Space Empire would give the game some much needed progression and goals beyond simply building bigger and fancier rockets.

That cobbling together aspect that you mentioned would be part of the fun.

On the other hand, I totally get that other players will want to plonk down a base near all the relevant resources and just get it up and running with minimal fuss.

Edited April 20, 2021 by KSK

[Dientus]

2 hours ago, PlutoISaPlanet said:

It appears to be frozen.

I always thought it as a rocky dust ball like Mun... But if there's mint ice cream I guess it has to have water somewhere right?

1 hour ago, KSK said:

Beyond that, I guess it depends what kind of game the developers have in mind. Personally, I'm not a fan of Ore as a magic 'make anything' resource, the way we have it now, and would like the game to be a bit more about  exploring to find resources and setting up the infrastructure to move them around and make use of them. To me, building that kind of benign Kerbal Space Empire would give the game some much needed progression and goals beyond simply building bigger and fancier rockets.

That cobbling together aspect that you mentioned would be part of the fun.

Something along these lines is exactly what I'm hoping for myself, I do think it will be a delicate balance between what has been said previously to where it becomes more of a grind and a hassle versus just fun. Based on everything I have heard so far I am very optimistic that if KSP 2 were to have this style of intermediary resources included, it would be in a simple yet challenging way that wouldn't require constant attention or hassle, nor would it become a roadblock to the point of being game stopping.

[B.Riches2500]

On 4/19/2021 at 4:10 PM, PlutoISaPlanet said:

I absolutely agree that to get certain resources you should have a different colony or outpost.

Yep, 100% agree. Would also be an incentive to transport resources from one base to another (or perhaps even one planet/moon to another?).