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[DEVTHREAD] Deep Space Exploration Vessels

Angelo Kerman

By Angelo Kerman
in KSP1 Mod Development

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Keep pulsed plasma mode?  

33 members have voted

  1. 1. Keep pulsed plasma mode?

    • Yes, I use it
      14
    • No, I don't use it
      2

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Threadsinger

Threadsinger

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One "capstone" engine could be an antiproton-catalyzed drive of some kind for ludicrous isp/thrust at the expense of very expensive antiprotons. Not that I want to duplicate KSPI accidentally (which is an equally awesome mod for futuristic, but well thought out engine concepts), but that would be a logical step up.

One niche engine I'd like to see would be a radial, fusion VTOL drive. Snub nosed, dramatically less isp-efficient but very high thrust than a regular fusion engine, but designed to help VTOL craft land on planets. (But still keeping it better than using conventional rocket engines - it's a fusion drive, after all). Maybe add an overheat mechanism, where you've got only 20-30 seconds at full thrust before it overheats, to compensate for it's relatively high TWR/isp ratio. I've been looking for something like this (that wasn't worse than a regular chemical engine) for near-future VTOL'ing. Is there a market for that?

Also, I hope you don't plan on putting too many crazy gameplay restrictions for using engines - Kerbals don't even have food, gravity, or lifesupport needs! I'd say let cost, science, weight, and exotic/expensive fuels be the limiting factor, and let players build their ships with their choice of ridiculously-awesome tritium-powered mayhem drives.

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Angelo Kerman

Angelo Kerman

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One "capstone" engine could be an antiproton-catalyzed drive of some kind for ludicrous isp/thrust at the expense of very expensive antiprotons. Not that I want to duplicate KSPI accidentally (which is an equally awesome mod for futuristic, but well thought out engine concepts), but that would be a logical step up.

One niche engine I'd like to see would be a radial, fusion VTOL drive. Snub nosed, dramatically less isp-efficient but very high thrust than a regular fusion engine, but designed to help VTOL craft land on planets. (But still keeping it better than using conventional rocket engines - it's a fusion drive, after all). Maybe add an overheat mechanism, where you've got only 20-30 seconds at full thrust before it overheats, to compensate for it's relatively high TWR/isp ratio. I've been looking for something like this (that wasn't worse than a regular chemical engine) for near-future VTOL'ing. Is there a market for that?

Also, I hope you don't plan on putting too many crazy gameplay restrictions for using engines - Kerbals don't even have food, gravity, or lifesupport needs! I'd say let cost, science, weight, and exotic/expensive fuels be the limiting factor, and let players build their ships with their choice of ridiculously-awesome tritium-powered mayhem drives.

The pulsed plasma mode of the Supernova, with its really high ISP, definitely could fill the role of the antiproton-catalyzed fusion drive. I plan to make it a field-upgraded option that requires RocketParts and some science, and is done on a per-engine basis. Perhaps a further upgrade would boost the engine's thrust in pulsed-plasma mode.

I'll think on the radial VTOL drive, and add it to my list of potential parts for the mod.

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Angelo Kerman

Angelo Kerman

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Get the latest here.

- Added the FLM-100 radial storage tank. It slipped into the last update, so it's now officially ready for use.

- Deprecated the WB-120 radial fusion pellet tank.

- Removed the SpareParts storage template. Fixing DSEV vessels will require RocketParts (which, if you have Extraplanetary Launchpads, can be used to build rockets).

- Fixed an issue where the ArcJet RCS would still act like it is firing even when disabled.

- Fixed an issue where the HexPort allowed you to toggle the vestibule while in flight.

- Fixed an issue where the double hex truss allowed you to toggle the center vestibule while in flight.

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Angelo Kerman

Angelo Kerman

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Certainly interested in seeing what your visual take on a NSWR is :) . There's not that many visualizations floating around.

Thanks. :) If I can come up with something that fits game-wise then I'll add it in. It has to be good but not overshadow the Supernova.

Meanwhile, I've created a new release. Get the latest here.

0.3.15: Moar Thrusters

- Improved engine thrust on the Supernova. Hydrogen mode thrust has been increased to 900, up from 600. Pulsed Plasma mode is now 650, up from 150.

- Supernova now consumes fewer FusionPellets when idling.

- WB-2 reactor will start idling when its EC resource is full. When idling, it consumes fewer pellets.

- The WB-2 reactor shows how much EC it produces when running.

- Added the RT-5 ArcJet RCS Thruster. It offers RCS thrust in 5 directions for more epicness.

- Reduced the thrust power on the ArcJet RCS thrusters to 1.2kn (half what it was before and more in line with stock RCS).

- ArcJets require 150 EC/sec.

- The ArcJet RCS thrusters can be started, stopped, and toggled through Action Groups.

- Added the WBR-12M Radiator, a small radiator for the fusion reactor. It needs more artwork but it is functional.

- Radiators now measure in terms of Celsius © instead of speed of light ©. It's still better than negative Kelvin... ;)

KPRvuh2.jpg

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Angelo Kerman

Angelo Kerman

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Just a heads up that I found an issue late last night with mixing large and small radiators on the same craft and running the Supernova. I should have a fix later this week. If I don't then for now, don't mix the two radiators.

edit: due to the major changes coming in 1.0, I'm simplifying the heat management system so that radiators won't explode. It will be ready after 1.0 releases.

Edited by Angel-125
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mckamx

mckamx

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I installed DSEV for the centrifugal system. However, after getting a contract to test the SuperNova engine, I decide to give it a try. My first design had insufficient radiator panels (it was a testbed system, after all), so I cracked down the thrust limiter to keep the radiators from melting. However, on its first real mission (Jool and back), I noticed that the Delta-V listed for the propulsion module by both MechJeb and KER did not match what I was actually seeing - it was taking almost twice as much LiquidFuel to make a maneuver as MechJeb and KER was saying it should.

emvZlZG.png

I see several possibilities for why the engine is not working as I expect:

* I am assuming the thrust limiter essentually just dials back the throttle, so has no effect on DeltaV or ISP

* I am assuming that the maneuver node deltaV, when the orbit radius is large (so prograde is basically constant for the length of the burn) should closely reflect the deltaV loss reported by MechJeb / KER after completing the maneuver.

* I noticed an oddity - that MechJeb was reporting "angle to prograde" as 93 deg, when the burn was almost exactly prograde according to the navball and my understanding

* I am using DSEV v0.3.13 (once something is basically working, I usually change versions only when I change game saves, which is usually when a new version of KSP is released)

Can anyone give me some pointers on what might be happening here?

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Angelo Kerman

Angelo Kerman

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I believe the thrust limiter currently just limits thrust, not isp. It definitely won't affect delta-v. However, 1.0 will apparently affect isp based on thrust. Not sure about tthat, but next week is bringing a lot of changes to the game.

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mckamx

mckamx

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My current speculation (I haven't done the math to see if it deserves hypothesis status): the low thrust is what is causing the efficiency problems.

Details: I am doing a burn within the Jool system, where the gravity well is fairly deep. If I was doing an impulse burn (full deltaV change in 0 time), the MechJeb prediction would be true. However, because I am spreading my burn over a long time, each instant of burn I have to subtract off the current SOI gravity field from my thrust. In a low gravity field, or with high TWR, this is negligible. However, in a high gravity field, with very low TWR, my thrust may be only a few times the gravity field, so the net effect is a very inefficient burn.

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Angelo Kerman

Angelo Kerman

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I was talking about this mod with my friend the other day and he actually said it should merge with prokjet's nuclear engines mod lol:D. But seriously, this is never going to happen, right?

I love PorkJet's engines and his Atomic Rockets mod is way cool. But the two mods won't be merging. That said, DSEV will work alongside Atomic Rockets if installed. :)

Edited by Angel-125
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ChrisSpace

ChrisSpace

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... for example, if the isp at 100% thrust was 9000s, at 50% thrust it would be 18000s, at 33% thrust it would be 27000s etc etc...

Hey, you remember when I said this about inertially confined fusion engines? Well, I will admit I did not do my research long enough, it turns out there are several fusion engines, both inertially and magnetically confined, that have this characteristic. So perhaps the supernova can exchange thrust for isp as well:D

Also, I had some more ideas for engines and their gameplay niches (most of these ideas came from my friends actually, and I tried really hard to limit the number of posted ideas to unique ones only):

TRINITY nuclear pulse propulsion unit

mass: 200t

thrust: 2,220kN

isp (vac): 2000s

fuel: nukeunits

gameplay niche: the first orion nuclear propulsion system. TWR is only just a little bit above 1, so this is not for lifting off kerbin. also, the international kerbin environmental protection organization (IKEPO) would not be very pleased.

SPRAYER open-cycle gas-core nuclear thermal rocket

mass: 200t

thrust: 3500kN

isp (vac): 3600s

fuel: liquidfuel

gameplay niche: a high-thrust high-isp nuclear engine with radioactive exhaust

ATR Solid-core antimatter thermal rocket

mass: 5t

thrust: 440kN

isp (vac): 1100s

fuel: antimatter and liquidfuel

gameplay niche: a step up from the LV-N nuclear engine

IVY MIKE nuclear pulse propulsion unit

mass: 1700t

thrust: 80,000kN

isp (vac): 4000s

fuel: nukeunits

gameplay niche: a mid-sized nuclear pulse propulsion system, quite massive and powerful

FLARE IC-fusion engine

mass: 4t

thrust: 80kN

isp (vac): 15,200s

fuel: fusionpellets

gameplay niche: a small fusion engine for small spacecraft

FREEDOM closed-cycle gas-core nuclear thermal rocket

mass: 40t

thrust: 4000kN

isp (vac): 3000s

fuel: liquidfuel

gameplay niche: very heavy high-efficiency payload lifting

KITE photon sail

mass: 16t

thrust: 0.185kN, when at kerbin's distance from kerbol

photon sail dimensions: 4km x 4km x 300nm

gameplay niche: solar photon sail. requires no propellant. works best close to kerbol.

Edited by ChrisSpace
removed some more engines
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Angelo Kerman

Angelo Kerman

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Wow, that's quite the list! Thanks for putting that together. Based on my vision for the mod though, the Supernova is the best engine offered. The next engine I do will offer performance in between the Supernova and the NERVA (what we knew as the LV-N, which now burns liquid fuel only, apparently). The Trinity NSWR motor would be too overpowered, so the Triton, with its high-thrust mode that's a step behind the Mainsail and consumes LFO, and its low-thrust mode that is liquid fuel only but is still more thrust than the Nerva, should fit the bill. I also want to make a 0.625m mini-nuke that can be stacked or radially attached. Hm... that might be a reason to redo the nuclear aerospike... They will have to wait though, I'm still working on refining the existing parts.

This weekend I tossed out the existing heat management system and abstracted it in the interests of game play. You still have to worry about overheating, but for the time being it won't be tied to part temperature (at least until I see how 1.0 affects temperature). Oh, and the mod now gives you a custom part category, and the ArcJet RCS thrusters are fixed, and the Supernova and fusion reactor remember their last state. So pretty much the mod is ready for 1.0, and just needs an update to ModuleManager and InfernalRobotics. :)

Edited by Angel-125
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ChrisSpace

ChrisSpace

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Okay, I have removed all the mega-overpowered late-game engines, so now it is easier to see my (and my friends') other suggestions.

The Trinity NSWR motor would be too overpowered, so the Triton, with its high-thrust mode that's a step behind the Mainsail and consumes LFO, and its low-thrust mode that is liquid fuel only but is still more thrust than the Nerva, should fit the bill.

What? Why can't we add both? As far as I could tell, the NSWR was perfectly balanced with its destroy-everything-when turned-on quality. In fact, I specifically did not add NSWR because I thought you were already on it.

And if you plan on making the supernova the absolute end-game engine, its isp might need to be bumped up a little (the discovery II's engine isp was a bit over 35,000. scaled down for the kerbal universe, an isp of 20-30k would be best)

Edited by ChrisSpace
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Angelo Kerman

Angelo Kerman

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Okay, I have removed all the mega-overpowered late-game engines, so now it is easier to see my (and my friends') other suggestions.

What? Why can't we add both? As far as I could tell, the NSWR was perfectly balanced with its destroy-everything-when turned-on quality. In fact, I specifically did not add NSWR because I thought you were already on it.

And if you plan on making the supernova the absolute end-game engine, its isp might need to be bumped up a little (the discovery II's engine isp was a bit over 35,000. scaled down for the kerbal universe, an isp of 20-30k would be best)

It was 35k in the paper because the thrust was so low, about 68kn. In the NASA paper, the engine is designed to run continuously. The ship flips around mid way to slow down. Since KSP doesn't let you do that very well (it would require many hours of boredom) I chose to increase the thrust and decrease the ISP in the interests of gameplay. My test craft, with four 3.75m liquid hydrogen tanks from NFT, gets something like 56k delta-v. You can go anywhere in the kerbol system and back with that much delta-v. If that isn't enough though, the engine performance is done through config files, so you can easily change it to your liking. :)

My other idea I am toying with is an ArcJet based engine. Basically, take nine of the RCS thrusters and cluster them together. You'd get a paltry 10.8kn of thrust and you'd eat through 1,350ec/sec, but it might be useful in some situations.

Edited by Angel-125
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ChrisSpace

ChrisSpace

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Good point with the supernova engine. perhaps instead it can trade throttle for isp? As in, at 100% thrust the isp would be 15,000s, at 50% it would be 30,000s, etc? That way we get the best of both worlds.

Also, I might as well remove some of my other low-thrust high-isp engines from the list now...

(But i'm still keeping the KITE on the list because I like it)

Edited by ChrisSpace
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Angelo Kerman

Angelo Kerman

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So, good news and bad news. Bad news: radiators will remain dark until next week-ish while I sort out the new heat mechanics. Good news: mod will be 1.0 ready by tomorrow night, and has new parts. More good news: in my quest to get the radiators working again, they will be able to cool the entire spacecraft.

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Angelo Kerman

Angelo Kerman

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Thanks guys! And more good news: I have my radiators working! DSEV radiators will go through all the parts in a vessel and attempt to cool them down to ambient temperature- or room temperature if the part has crew capacity. The radiators themselves take on the heat. This is all done within the game's heat system, so parts attached to the radiators may get hotter. That said, I had a Supernova running full throttle on the pad and staying a nice cool room temperature. :)

So not only will they cool the Supernova and fusion reactor, they can cool fuel cells, drills, and ISRU processors, and LV-Ns...

Radiators have Coolant, a resource with good thermal mass per unit. But I've set up the module so that you can specify different types of coolants, such as liquid fuel, oxidizer, and monopropellant if you wish.

My radiators support both closed-cycle and open-cycle cooling. With open-cycle cooling, you can rapidly cool the radiator at the expense of venting Coolant. The nice thing as this paves the way for those liquid droplet radiators that I've wanted forever...

Edited by Angel-125
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Whizzkid

Whizzkid

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Thanks guys! And more good news: I have my radiators working! DSEV radiators will go through all the parts in a vessel and attempt to cool them down to ambient temperature- or room temperature if the part has crew capacity. The radiators themselves take on the heat. This is all done within the game's heat system, so parts attached to the radiators may get hotter. That said, I had a Supernova running full throttle on the pad and staying a nice cool room temperature. :)

So not only will they cool the Supernova and fusion reactor, they can cool fuel cells, drills, and ISRU processors, and LV-Ns...

Radiators have Coolant, a resource with good thermal mass per unit. But I've set up the module so that you can specify different types of coolants, such as liquid fuel, oxidizer, and monopropellant if you wish.

My radiators support both closed-cycle and open-cycle cooling. With open-cycle cooling, you can rapidly cool the radiator at the expense of venting Coolant. The nice thing as this paves the way for those liquid droplet radiators that I've wanted forever...

So is it 1.0 compatible now? or is there more to do?

Awesome looking mod BTW

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