Search the Community
Showing results for tags 'rebalance'.
Found 3 results
S A F I R E - Stockalike Adjustments to Fuels, ISRU, Ratios and Engines Main ideas: 1 stock resource unit = 1 kg -> check propellant mass just looking at the units Oxidizer : Fuel ratio = 3:1 for all LFO rocket engines -> more realistic and great for semi-direct ISRU, where you can produce locally only part of propellant Rocket engines generally cost 60% more, tanks cost ~60% less and rocket fuels cost much less -> more or less same rocket costs but with much more realistic distribution - better for reusability, TSTO, SSTO and drop tanks designs ISRU produces only Oxidizer from ORE; no heat, needs high energy input and is slow -> no more unlimited fuel production, realistic ISRU operation, semi-direct missions (produce 75% of your propellant, bring the rest with you) This is a continuation of an idea from couple of years ago, you can read more about it here How does it look in-game: https://imgur.com/a/yM5sagD Requirements: Module Manager by Sarbian. Warning: Save-game breaking and not compatible with old and stock vessels because it doesn't update values in old saved craft parts. New vessels should work fine. DOWNLOAD 0.2.0 GITHUB CONFIRMED COMPATIBILITY: - SMURFF - Making History Expansion - Rescale mods such as Sigma Dimensions CURRENTLY NOT COMPATIBLE WITH: - mods using Community Resource Pack, procedural and fuel switch modules Changelog:
Fuel and ISRU rebalance mod [FIR] Source: MIT AeroAstro presentation "Utilizing Molten Regolith Electrolysis Reactors to Produce Oxygen on the Moon", 2015. The Installation shown above is designed to make 10t of oxidizer per year. What is this mod about? Brief summary: FIR is a mod that rebalances prices of stock fuel (cheaper) and mixture mix used by stock engines/fuel cells (3:1 instead of 1.1:0.9). Additionally it makes behaviour of stock ISRUs a bit more realistic (can only produce oxidizer from ore + work much slower + other tweaks). The mod aims to approximate KSP stock behaviour to reality and thus be a middle ground between the stock game and mods like RO/RealFuels. Detailed description: This is a mod that rebalances couple of things that limited my gameplay and at the same time the learning value of KSP. 1) stock ISRU can only produce oxidizer now. And it is a very slow process (however faster than in reality). ISRUs, scanners and ore tanks are moved earlier in the tech tree. Rationale: Oxidizer only - Making oxidizer of any kind from ore (regolith) is broadly researched in many working papers concerning both Mars and Moon. It's decisively simpler than making all parts of propellant and can be done virtually anywhere by 'just' heating feedstock to a high temperature (in a process called Molten Regotlih Electrolysis). It also doesn't require any inputs except energy. Conversely making both oxidizer and fuel out of ore or even water is quite complicated (taking into account all requirements that accompany off-world manufacturing) and energy intensive process - to such an extent that even known papers about it seems to not get past theoretical stage (G. Landis and others). For now the most advanced in testing, simplest and reliable technology assumes making only oxidizer part of fuel. Lower processing speed - the most advanced MRE ISRU designs currently tested (on the picture above) are able to make about 10t of oxidizer a year assuming continuous operation (on the picture above).In comparison a small stock ISRU is able to churn out the same amount of oxidizer in an hour (0.55 unit/s * 5 kg per unit * 60 * 60 = 9.9t). Therefore my mod is going to rebalance small and normal ISRU's LOX production to about 28t and 160t per Kerbin year (1.2 and 6.6 jumbo tanks accordingly). Increased weight - in reality MRE regolith>oxidizer making system (so ISRU+tanks+power source) has a weight efficiency of about 5-7 (measured as a weight of oxidizer production per year divided by ISRU system weight). Therefore meeting production quota above (28/160t) would require much heavier ISRU units. Again I'm happy with approximation to reality so the mod make small ISRU weigh 2t and large 8t. Moreover large ISRU is much more efficient so there is a reward for bringing larger ISRU to the planet's surface. Lower technology requirements - by moving tech requirements earlier the main difficulty is moved from researching the technology to actually making it work. So the player would need to send and ISRU system in advance to produce fuel (so similar to assumptions of some current MARS/Moon missions). It should create interesting situations when player can utilize ISRU before upgrading science compound in a career game. Therefore with careful planning he can extend the range of lower tech rockets and reach further planets so the gameplay could be more interesting in early career compared to late game. Energy demands for small isru remain unchanged at the moment. Standard ISRU however has 4x higher EC demand (4x bigger size and 50% better efficiency = heating more regolith to a higher temperature). 2) Changed fuel mixture ratio for stock tanks, engines and fuel cells to 3:1 (from 1.1:0.9). This is a compromise as to what stock LiquidFuel might be since sometimes it acts as RP-1/Kerosene (jets, big engines) and sometimes as liquid hydrogen (LV-N). Rationale: 3:1 ratio seems to be a good compromise and generalized mixture ratio that encompasses different fuel types: Typical oxidizer to RP-1 mixture ratio = 2.56:1 (RD-180 2.72:1) Typical oxidizer to methane mix ratio = 3.2:1 Typical oxidizer to liq hydrogen mix ratio = 5:1 *(from 4:1 to 8:1) So we can see that no matter what popular fuel mix we take they always use more mass of oxidizer than fuel. This means that player can refuel now a significant portion of a fuel (75% of mass) in the form of oxidizer. Also 3:1 ratio means that it's easier to make quick calculations by seeing whether you have more than 3x times more oxidizer than liquid fuel. 3) Liquid fuel, oxidizer, monopropellant and solid fuel are much cheaper now. So player using SSTO or recovering stages gets much higher cash bonus than before. Rationale: I didn't like how my big SSTOs or rockets still used quite a lot of fuel even though they were recoverable. In stock KSP - depending on your design - fuel costs can comprise even 10-20%+ of a spacecraft or almost 40% of a stock tank. In reality fuel costs are about 0.4% in case of a space shuttle so very little compared to space vehicle costs. Since the parts' total cost remains the same, the parts' dry cost is relatively higher while fuel price is So now player that invests a lot more time to build recoverable parts or/and fly SSTOs is rewarded with higher percentage of recovered funds. 4) - for people using Atomic Age mod by porkjet - I've changed fuel mix and isp value for LANTERN engine in Atomic Age Nuclear Propulsion mod by porkjet: Using stats from this page: http://www.nss.org/settlement/moon/LANTR.html and reducing isp to stock values, I've increased slightly isp in LOX augmented mode to 500isp instead of 455. In reality isp for 3:1 fuel mix is expected to be in range of 631-647s. Isp for LF mode only remained unchanged (720s). LOX augmented mode uses now 3:1 fuel mix. Therefore LANTERN engine has now the highest isp (500) from all engines that can be refuelled with an oxidizer (since LV-N can't be refuelled with new ISRU mechanics). Aside from more challenging and (imho) interesting gameplay this rebalance increases educational value for KSP; a player: - can see that oxidizer is making a bulk of the rocket fuel (similar to real world) - observes that ISRU can extend range of the rocket by making only oxidizer however implementation of it requires planning ahead (similar to real life). Also it's rather not viable as a part of a spaceship due to system mass (heavier) and rate it produces oxidizer. The main purpose of it is now to sit on a surface of a planet and produce small amounts of oxidizer for the long time. - can note that fuel costs in rockets are very small thus researching and developing reusability is a key point to savings and extending the space program. And the last point - if you still reading -this mod will be a basis for my next mods which involve low-tech/low-isp alternative isru fuels/propulsions that were researched extensively due to the ease of implementation compared to more advanced/complicated and therefore less viable solutions. No download link yet, the project is on the drawing board at the moment. I welcome all suggestions and discussion about the mod and ISRU stuff in general:)
From what I've seen and heard, it's pretty widely agreed that the current command modules aren't very well balanced. There doesn't seem to be any good mechanical reason to use any of the 2.5m parts - you can always get the same capabilities by using multiple 1.25m modules stuck together - and even that's usually just the Mk1 Lander Can. In the spirit of making each command module worth using without just outlawing half of them from the game, here's an attempt at a rebalance. First, the current stats of the pods (and the hitchhiker pod, which while technically not a command module is still relevant). Cockpits are not included - I simply don't have a good feel for those parts: When you look at mass-adjusted stats, the Mk1 Lander Can simply beats the pants off any other part in both raw kerbal carrying capacity and monoprop capacity. It's second to only the cupola in battery capacity, and third in torque. It isn't great in stats that don't vary on weight, but to be honest, those don't really matter. A Mk1 Lander Can with a parachute and an empty heatshield still only weighs as much as the next lightest command module. Conversely, the Mk1-2 Command Pod is really truly awful. It beats only the cupola in kerbal-carrying capacity and is the outright worst part in every other stat. The mass-unadjusted stats are a little better - but those are generally pretty easily mitigated with additional parts that are ultimately much lighter. Making all of these effectively size-scaled copies of each other isn't any better - we'd still be functionally down to a single part. Hopefully my changes give each part a useful and distinct role: Mk1 Command Pod: This part is untouched. Mk1-2 Command Pod: Dry mass reduced from 4t to 2.4t Torque cost reduced from 0.08 charge/kN⋅m to 0.04 charge/kN⋅m Mk1 Lander Can: Critical skin temperature reduced from 2000K to 1200K Impact tolerance reduced from 8 m/s to 6 m/s Battery reduced from 50 charge to 25 charge Mk2 Lander Can: Dry mass reduced from 2.5t to 1.2t Critical skin temperature reduced from 2000K to 1200K Battery reduced from 100 charge to 60 charge Torque per axis reduced from 15 kN⋅m to 10 kN⋅m Torque cost per axis increased from 0.05 charge/kN⋅m to 0.06 charge/kN⋅m Hitchhiker Pod: Dry mass reduced from 2.5t to 2.2t Impact tolerance increased from 6 m/s to 10 m/s Cupola: Dry mass reduced from 1.76t to 1.35t Battery capacity increased from 200 charge to 1000 charge Monoprop capacity increased from 10 to 100 Torque per axis increased from 9 kN⋅m to 30 kN⋅m Torque cost per axis reduced from 0.1 charge/kN⋅m to 0.02 charge/kN⋅m Probe core with basic SAS (ie, stability assist only) added to the part. This drains 1.2 charge/minute (this is equivalent to an OKTO). Crew reports still require a kerbal, and if a level 2+ pilot enters the cupola their maneuver abilities are used instead. Critical skin temperature reduced from 2000K to 1500K Impact tolerance reduced from 8 m/s to 6 m/s Dry cost increased from √3188 to √4380 The state of the new parts is summarized below (does not include cost or probe core modifications to the Cupola): All of these changes can be made using nothing more than Module Manager - this guarantees that the changes are both easy to make and easy to setup as a mod for testing. My rationale for each part is listed below. As a general rule I wanted to maintain the weight of a seat in a category (command pods are 0.8t/seat, lander cans are 0.6t/seat) but make the larger parts a little more useful in other aspects. Mk1 Command Pod: Everything is already functionally balanced to this pod - starting engines, parachutes, fuel tanks - so I was totally uninterested in messing with it. Instead, I've used it as a benchmark for roughly how useful a part should be in its niche. The full suite of changes I'm proposing make the command pods the durable choice - particularly good for re-entry - Mk1-2 Command Pod: This part already had triple the seats, monoprop capacity, battery, and torque of the Mk1 Pod, so the natural thing to do was to reduce it to triple the mass as well. The charge required per unit torque was reduced to make it a little more efficient than Mk1 Pod. The high impact and thermal tolerances really work with the "durable re-entry module" theme of the command pods, so I left that. Mk1 Lander Can: Lander cans should be lightweight. They should not survive re-entry from Mun without any shielding. The thermal and impact tolerance nerfs should give the lander cans a defined role (other than "awesome at everything", which is this part's current role). The part still felt too good to me, but I understood why monoprop would be useful in lunar-orbit rendezvous lander. Limiting the battery made the lander can worse than the command pod in every stat except weight and monoprop, which is about where it belongs in my opinion. Mk2 Lander Can: The weight and critical skin tolerances brought this in line with the new Mk1 Can. It's now a little better in battery, monoprop, and torque than the Mk1 but still worse than either command pod in all of those except monoprop. This probably still won't be great for small landers, simply because 1.25m engines weigh less, but it'll be a good choice for slightly beefier ones. Hitchhiker Pod: The Mk1 and Mk2 Crew Cabins both carry 2 seats per ton, and have 40+ m/s impact tolerances. This weight reduction brings the hitchhiker pod in line with those in terms of carrying capacity. I don't understand why it had such a low impact tolerance in the first place - the basic fin is the only part in stock with a lower impact tolerance than 6 m/s. Cupola: This part is in a rough place for balance. This part obviously belongs on a space station (or a mothership - they're nearly the same thing), so impact and thermal tolerance aren't a big deal. On the other hand, it shouldn't be light enough to become a strong competitor for normal rockets. One step is to give this phenomenal battery, monoprop, and torque, and to make the reaction wheels more efficient. That still isn't really enough in my opinion, so I decided that the reasonable thing to do with the Cupola was to make it the next-best thing to a complete space station in a single part to help keep part count down - and that meant adding a probe core so that the space station could still function even without a kerbal. The only things this part is really lacking are power generation and an antenna. For comparison, a Mk1 Pod with an OKTO, 1k battery, large reaction wheel, and an empty 150 unit monoprop tank only weighs 1.4t, so this isn't really even particularly lighter. I've tested all of these in my own install, and they all seem reasonable to me. I'm not the only person in the world though, and I'd like to hear some other opinions.