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Preposterous hydrogen thruster tech - stress testing

Discussion in 'Balancing' started by Spavvy, Apr 14, 2016.

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This last post in this thread was made more than 31 days old.
  1. Spavvy Apprentice Engineer

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    188
    I did a stress test.
    I used:
    1 large cargo container with a capacity of 4210000L - x10 inventory (as wiki states, base capacity is 421000L). 1 of the updates stated, that the density is divided accordingly to the cap multiplier, so that you can pack more stuff, but keep the same mass. If im wrong about that, correct me
    1 hydrogen tank
    1 oxygen generator
    1 small reactor
    1 gyroscope
    1 pilot seat - the chair without the screen
    All of that in large ship grid.
    The oxygen generator was empty. So was the hydrogen tank. It was the creative mode for prototyping.
    The cargo container was filled with about 89Mt of platinum ingots - 4210000L of it. Why Pt? Cause its the densest thing you can get in SE - using this gives you the maximum load.
    Next i stated attaching downwards facing large hydrogen thrusters in pairs. I kept adding them, until i was able to lift off of Earth-like planet with a gravity of 1G. Once i managed to lift off i started removing the excess thrusters, to narrow down the amount of thrusters required to a minimum.
    It takes 15 (FIFTEEN) large thrusters to pick up 1 crate. A ship made out of nothing but bare minimum components requires 15 engines to fly up.
    Heres why its preposterous:
    Game about building space structures with convenient living envirnonmet in a space age, where there are gravity generators, jump drives and powerful, reactionless ion thrusters requires Saturn V level of ancient technology and efficiency to leave planets with cargo holds full.
    Test was done with a maximum loadout to ensure the vessel is capable of lifting ANYTHING you put into the storage. Thats how youre supposed to design and build ships, right? To fill them up to the brim and carry that around space. Not to have a storage, but never fully use it. Not only not fully - conveniently - how much thrusters are you willing to put on your transporter? 15? For 1 box? And how many for lifting the rest of the ship? 7? Is having 1 large cargo container enough to call the ship a heavy transporter? Is it a good idea to carry lots of cargo 1 box at a time? We are free to gather as much of anything as we want and we probably will never gather that much platinum, but then we are disinsentivised from using the most of our storage. If not to test with Pt, what to test with? Iron ore? With how much of it? And will such a test give you an idea of how much stuff of many varieties can you actually load onto a ship? Again, your box will be able to intake 421000L X capacity modifier of items, that might end up being heavier, than what youve measured with, leaving you with a ship, that doesnt do its 1 job.

    Tell me, am i designing cargo ships wrong? Show me your ships and tell me how much of what can they carry. Am i mistaken, that density is adjusted accordingly? Or is it, in fact so, that we are forced to build ships made out of 40% fuel, 55% thrusters and 5% cargo to get off the ground, like in the stoneage of Saturn V? This is why we invented Ion thrusters, gravity generators and Red1 - so that space travel is convenient, affordable and not strenuous. But now its all useless, cause we are bound by gravity.
    Should we get rid of gravity? Not necessarily. We did invent gravity generators and we couldve used that to counteract the planetary pull. But if not those solutions, then what?
    Perhaps, since removing hydrogen tank, hydrogen thrusters and "natural" gravity isnt an option, since that would undermine the effort put into the game development, maybe we (that is you - the developers) could change those hydrogen rockets into whatever kind of stretch of sci-fi, which allows for the return of convenient space travel and convenient gameplay. They might still use some kind of fuel, but in return, they should be stupid powerful.

    Carrying cargo 1 box at a time is silly and building ships exclusively out of thrusters is ridiculous.

    I post this in Feedback - its not a bug, that the system is jank by design, its not a matter of suggesting a feature. Its a matter of balancing the game. Giving you the feedback on the consistency of the world we immerse ourselves in during the play, its mechanics.
     
    • Disagree Disagree x 3
    • Agree Agree x 1
  2. Ralirashi Apprentice Engineer

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    306
    It takes 15 thrusters to lift a ship with an equivalent of 10 cargo containers is what you're saying. Or 1.5 for a single box.
    Your test is correct: you have to test lifting capabilities at maximum load. However, you configured your environment incorrectly. You increased the maximum load tenfold. Why are you surprised that you need to increase your lift tenfold?
     
  3. Dakroth Apprentice Engineer

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    144
    @Ralirashi The question is whether or not the mass is scaled with the inventory multiplier. If an object takes up 1/10th of the volume and only has 1/10th of its base mass when inventory multiplier is set to x10, then the result should be exactly the same as if he had done the test at 1x inventory. If mass *does not* scale, then your question is valid.

    For the record, I've built hydro-powered rockets on 1x inventory that consist of only the essential components, one large thruster and some visual extras, and those are able to get everything needed for a good-sized base off of the earth-like planet just fine. Large cargo wasn't full, of course, but it didn't need to be.

    @Spavvy A couple of thoughts: First, I would recommend re-trying the test on 1x inventory to se if the effect is the same. Second, while you are correct about the engineering-for-full-load aspect, I would suggest that you went off-track by using platinum ingots. Yes, they are the densest item in the game, but who is going to be lifting large cargos worth of platinum off the surface of a planet? Unless you're on a custom planet, platinum has to be brought down first. The reason I ask this is because you must bear in mind what these rockets would likely be used for. Perhaps try the test with intermediate mass objects like steel plates, of fill the cargo with ore. Another thing I would point out s that in the event that someone isready to be heavy-lifting off of a planet, they would either have already gone to space, thus having access to platinum and ion thrusters (to take load off of the hydrogen thrusters once they start working again,) or have the resources to do something like use multi-stage systems, such as detachable large atmo thrusters that are used up until they no longer function and then are jettisoned.

    I again go back to the use of platinum for the test. I would point out that actual rockets lifting actual things into actual space tend to be limited to carrying relatively small loads because of the very problem you are having. That's why we don't lauch rockets full of water, for example. (Water sucks.) In the event of heavy-lift operations, perhaps it would ultimately be better to use small cargos instead?

    Also, if you want to be sure that you have accurate data, I recommend using the Build Info mod. Very helpful.

    -Dakroth
     
  4. Spavvy Apprentice Engineer

    Messages:
    188
    So yeah, i did retry the test with "realistic" (x1) inventory space and, as usual:
    Mass was the same, number of engines was the same, i was right and instead of being corrected i was proclaimed wrong.
    |
    |
     
  5. Dakroth Apprentice Engineer

    Messages:
    144
    Then engineer around the problem. Can't afford to lift an entire large cargo ful of whatever? Build a smaller ship.

    -Dakroth
     
  6. Dakroth Apprentice Engineer

    Messages:
    144
    Also, no one "proclaimed you wrong." If anything, we restated something in terms as we understood them. I post to input my ideas into a discussion, not to say someone is wrong or defame them or what have you. Imagining yourself a victim of some attack doesn't help here.

    As for your return to your Saturn V comment, hydrogen can only put out so much power period. Rocket fuel is inherently weak relative to its required mass load cost, but you already knew that, I'm sure. If you want more power out of your future rocket to lift amount of cargo that are otherwise too large for the ship you have designed, there are plenty of mods to help you out there. In the case that you don't want to mod, refer to my previous comment. There are, as I have previously stated, several alternatives to simply building a single stage large hydrogen thruster lifting system. There is no one-size-fits-all solution to getting out of gravity, but that's part of the challenge. Find a way to build a better ship. Engineer.

    Remember, I'm giving suggestions here, not calling you an imbecile. If you have comments or counter arguments, for the love of civility, articulate them rather than re-posting what you've already said.

    -Dakroth
     
  7. Harrekin Master Engineer

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    3,077
    In Sci-Fi they build the heavier ships in space for a reason...
     
  8. Dakroth Apprentice Engineer

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    144
    This is true, but there are other sci-fi 'universes,' StarGate, for example, where you have large spacecraft with dual purpose thrusters that function equally or reasonably well in atmosphere or outer space. That's something that this game doesn't have, particularly since the ion thrusters are incrementally nerfed as you go deeper into a gravity field. Personally, I was hoping that ion thrusters wouldn't be affected at all so you would be able to build large ships that function like what I described just previously. Sort of as a reward for being able to escape the planet and acquire enough platinum for the thruster components.

    -Dakroth
     
  9. Spavvy Apprentice Engineer

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    188
    You dont have to sign your posts.
    "build a smaller ship" isnt a solution to "we have a large container at our disposal".
    Its the time of easy, convenient space travel. That means fast, cheap and not physiologically straining. Thats why we have GravGens - to not have our muscles and bones atrophy. And we can use them to effectively lift mass of 0kg with the thrust of lots of newtons.
    But no, we need a "challenge".

    And yet they can come down to a planet and lift off with ion engines.
     
  10. Harrekin Master Engineer

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    3,077
    Citation?
     
  11. Spavvy Apprentice Engineer

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    188
  12. SpecFrigateBLK3 Senior Engineer

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    1,133
    Star Wars tech is drastically OP. Space Engineers is, best guess, 2077 or soon afterwards.
     
  13. viertar Trainee Engineer

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    36
    it already has gravity generators, though, so theres a solution, but some1 thought solved problems need new problems for balance
     
  14. Phoera Senior Engineer

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    1,713
    if i understand correcrly problem in topic is the fact that
    inventory scales, mass scales, but engine power not scales, right?
     
  15. Blako Apprentice Engineer

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    385
    I'm going to start doing similar tests but using my script I'm going to try and pull 4gs of (vertical) acceleration in space when empty and see if that equals 3gs of acceleration on the surface when empty. Then I will start adding cargo and see what happens.

    On a side note a ship with ion thrusters did 1.4gs of vertical acceleration in space and yet on the surface it could not hover. Thus ions becoming less efficient in atmosphere was confirmed.
     
  16. SpecFrigateBLK3 Senior Engineer

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    1,133
    As I recall, ion thrusters are approx. thirty percent efficient at an even one gravity.
     
    • Informative Informative x 1
  17. viertar Trainee Engineer

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    36
    wrong, problem is theres not enough power and we cant circumvent it by using gravgens to create 0G bubble around the ship and make it effortless to move
     
  18. SpecFrigateBLK3 Senior Engineer

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    1,133
    If that were possible it would completely remove the challenge of designing a ship capable of exiting the gravity well.
     
  19. Merandix Junior Engineer

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    519
    Some comparisons with real life thrusters. I used roughly 0,8 to 1,02 kg per litre for RP1, and roughly 0,07 kg per litre for LH2 (Liquid Hydrogen takes up ridiculous volumes).
    I also get that KSH will likely completely forget about an oxidiser also being necessary for the sake of simplicity (to which I echo, why not change the name of 'hydrogen' to 'rocket fuel'?). I know it's not about realism, but it's a fun comparison either way. And considering conveyors use a lot of CPU performance, anything that can decrease the number of conveyors used seems like a good idea. I used sea-level thrust for all real engines.

    Large Ship Small Hydrogen thruster
    Diameter: 2,5 metres
    Mass: 1420 kg
    Thrust: 900 kN
    Burn-rate: (76 kg) 1,092.5 litres of 'hydrodgen' per second.
    Single engine burn time: 38 minutes and 8,3 seconds (on a full large-ship hydrogen tank)

    Space Shuttle Main Engine
    Diameter: 2,4 metres
    Mass: 3533 kg
    Thrust: 1800 kN
    Burn-rate: 411 kg (5871 L) of LH2 per second.
    Single engine burn time: 7 minutes and 5,8 seconds (on a full large-ship hydrogen tank, this one's obviously hypothetical)

    Okay, so our engineers CLEARLY sacrificed power for fuel efficiency compared to the SSME.
    Let's compare the large hydrogen thruster to the largest single chamber rocket motor humanity has ever produced, and the most powerful rocket engine ever built:

    Large Ship Large Hydrogen thruster
    Diameter: 7,5 metres
    Mass: 6940 kg
    Thrust: 6000 kN
    Burn-rate: (449,9 kg) 6,426.7 L of 'hydrogen' per second
    Single engine burn time: 6 minutes 29 seconds (on a full large hydrogen tank)

    Rocketdyne F1 (Saturn 5 main engines)
    Diameter: 3,72 metres
    Mass: 9172 kg
    Thrust: 6770 kN
    Burn-rate: (820-1046,5 kg) 1026 L of RP1 per second
    Single engine burn time: 40 minutes and 36,6 seconds (hypothetical, and unfair, since RP1 is WAY denser than LH2, using the same weight however, the tank could hold 175 tonnes of LH2, if it would hold the same mass of RP1, that would be depleted in only 3 minutes and 33,4 seconds when using 0,80 kg/L)

    RD-170 (Russian engine, most powerful ever built, but uses four combustion chambers and four nozzles)
    Diameter: 3,8 metres (total engine diameter, contains four smaller nozzles)
    Mass: 9750 kg
    Thrust: 7257 kN
    Burn-rate: ???

    Again, our engineers managed to crank up fuel efficiency. But not as notable as with the SSME. The main thing that stands out is that the Large Hydrogen Thruster is absolutely MASSIVE by comparison, yet pretty tame as far as thrust performance goes, the F1 is slightly less than half the diameter and only one fourth the exhaust surface, yet still more powerful. The fuel efficiency is again pretty great. (SE-numbers taken from the Space Engineers wiki)


    Also, space engineers wiki gives us a 2.500.000 m3 gas capacity ... which seems slightly ridiculous. The space shuttle external tank held 'only' 629.340 kg of LH2 (though a portion of it was reserved for LOX), that's 8.990.571 L or only 8.990,5 m3)

    I suspect that needs to read 2.500.000 litres, which is a much more sensible 175.000 kg of hydrogen (still, how they put 175 tonnes of fuel in a tank that ALWAYS has a mass of 8,1 tonnes regardless of it being full or empty).

    I think the balance would be a bit better with more powerful engines. Lets call the engines 'rocket engines' and the fuel 'rocket fuel'. Then change the thrust ratings. Up, to accomodate larger, more complex ship designs that are a bit lighter on performance and decrease the number of thrusters needed. I honestly feel as though 1800 kN and 12000 kN for the large and small hydrogen engines would be a lot more fitting (keeping the exact fuel consumptions as they have now). Wouldn't change ANYTHING in construction, except needlessly duplicating a lot of components. If you can build a ship that flies with two thrusters, you can also build it with only one. On that end of the spectrum, it hardly matters... but when you previously needed 20 engines, and now only ten, THEN it starts helping!

    Again, yes, I know my final conclusion is far from realistic; but I believe more powerful engines, gyroscopes etc would make the game much more accessible for new players, and far less frustrating for the very advanced players who start seeing serious performance drops because of the huge amounts needed of everything to move very large ships.
     
    • Agree Agree x 1
  20. Maddo Trainee Engineer

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    41
    Well that's your problem right there. Even a dump truck would fall apart if you filled it top to bottom with metal bars. Much less the densest material known to man.

    Don't think of this as being a bad thing, think of it as an opportunity to build different transports for different purposes.
    - Ones with small cargo, big engines and lots of weapons for carrying heavy valuable stuff.
    - Ones with big cargo, and fewer engines for carrying light cheap stuff (like ore).
    - And stuff somewhere in the middle for generic work.
    - And then of course there's different transports depending on the planets gravity or for deep space...

    OK I lied, not like anyone is gonna build multiple different transports (other than Keen), we'll all just make one transport and use it for everything, just leaving it partially empty when it hits it's mass limit.

    *I mean, I'm not even planning to build a transport. I just put a cargo box next to all my refineries and assemblers and call it good.
     
  21. viertar Trainee Engineer

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    36
    There shouldnt be a challenge there, thats the point. Its the age of easy space flight.

    No! See, its as if the game has no lore - no context outside of what is a player doing right now. "Youll never fill a container with that much platinum" - thats irrelevant. In an age of space explorations there would be companies that mine more than that on industrial level and need to haul the load over to sell it. And they are not gonna fly 1 small crate at a time, cuz they werent expected to fill that large box with it. And they are not gonna land it ingot by ingot on a planet.
    As its mentioned in OP: we are discouraged from using large crates, cause we might end up putting more mass than we wanted to carry, yet still have room in the container. So we should have just small boxes, each separate and with a merge block, so we transport only exactly as much as we can in most efficient space use. Yet we can warp spacetime around us.
     
  22. SpecFrigateBLK3 Senior Engineer

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    1,133
    Easy space flight? No, the point of the game is ENGINEERING.
    Small containers with merge blocks? Go for it dude. Also, perhaps large containers are meant for space only. Also keep inventory multipliers in mind.
     
    • Agree Agree x 1
    • Disagree Disagree x 1
  23. Maddo Trainee Engineer

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    41
    Good idea, you could have like a tugboat and barge setup. The tugboat used is always the same, but it gets hooked up to different numbers of barges (possibly even different types and sizes of barges) depending on how much each individual barge weights.
     
  24. thatguywithahammer Apprentice Engineer

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    179
    You could fit the planet Jupiter into one of those cargo containers if you squeeze it hard enough, but you wouldn't be at all surprised that you need more than 15 thrusters to lift a gas giant.

    Mass is what really matters, and those 15 engines are lifting over 9 thousand metric tons. That's equivalent to about 5.8 Landkreuzer P. 1500 Monsters -- self-propelled guns that, had they been built, would have fired projectiles heavier than a school bus.
    Also, filling the container with platinum is more achievable than squeezing a gas giant, but...
     
    • Agree Agree x 1
  25. viertar Trainee Engineer

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    36
    It wouldve been a good idea, if there was no large containers, that were just not supposed to use!

    @thatguywithahammer
    We already have GRAVITY GENERATORS engineered. The engineering now involves gravity generators. Now youre thinking with portals.
     
  26. SpecFrigateBLK3 Senior Engineer

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    1,133
    Except gravity generators DON'T FUCKING WORK in natural gravity. Don't give a fuck whether you think they should, they don't, and they're not gonna or they would already.
     
    • Funny Funny x 1
  27. viertar Trainee Engineer

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    36
    theres no such thing as "natural gravity" as opposed to "artificial gravity", thats not how physics work, all your suggestions are super valid, but suggesting to not bother with this ridiculous dichotomy is horrible, cause there needs to be some arbitrary "balance".
    But give us compact antimatter reactors to make it easier, though. Thats fair.
     
    • Disagree Disagree x 2
  28. SpecFrigateBLK3 Senior Engineer

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    1,133
    Work with the reality of the situation, not wishes.
    Artificial gravity is a crutch introduced into the game because of engine limitations and to help players by providing gravity where there is none.
    Logically speaking, any artificial means of inducing gravity would be heavily interfered with by existing gravity. ESPECIALLY if the artificial gravity is aligned to counteract existing gravity.
    Why? Think about it. You're trying to balance out the force exerted by an entire fucking planet.
     
  29. viertar Trainee Engineer

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    36
    WTF are you even on about? The game already did this 2 years ago. It does it now. You can move a gravity field into a gravity field and the vectors will add. And the existing gravity would interfere exactly as strongly as strongly it acts on anything. If its 9,81m/s^2 it merely 9,81m/s^2 and its the exact 9,81m/s^2 we can produce with 2,5x2,5(x2,5)m gravity generator. -1G + 1G is exactly 0G. We even have spherical generators, which would make the vectors addition even easier, since both are always radial.
    In other words "the entire fucking planet"'s force is about 10N. Not FUCKING much - thats why you can stand up and not have your spine crushed by Earths pull.
     
  30. SpecFrigateBLK3 Senior Engineer

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    1,133
    Every action has an equal and opposite reaction. By this logic, the force generated by a gravity generator would have to counteract both the force of gravity AND mass of an entire planet.
     
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