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AdmiralTigerclaw

Electromagnetic Reaction Control System (Or Reactionless Control System)

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This is a proposal and a request for someone who's got some parts modeling skills for an idea of a late-game advancement of RCS systems.

NAME: Electromagnetic Control System or 'Reactionless' Thrusters

PURPOSE: 'Fuel-less' electrically powered RCS thrusters.

LORE/THEORY:

No matter where you go in the Kerbol System, you encounter a magnetic field. Be it Kerbin's own Keomagnetic field, Kerbol's expansive electromagnetic dominance, or Jool's tremendous local field trapping precious antimatter, you can't escape the influence of an extremely powerful magnetic presence. It took our scientists playing with some motors in Zero G to suddenly realize the potential of these vast fields of electromagnetic force.

Motors operate on the mechanical force created from the interaction of two magnetic fields. One field usually being generated by a wire coiled through a rotating shaft; and the other by either a fixed magnet, or wire coiled around iron cores in a stator, or fixed point outside the shaft. When the rotor coils are energized, magnetic action generates mechanical motion in the form of torque. While normally this action is action is equally distributed in both directions, the right configuration of coils can result in an imbalanced force in the desired direction, producing magnetic 'thrust'. With the entirety of the Kerbol system all but saturated with huge, dominating magnetic fields, engineers realized the potential for utilizing magneto-mechanical principles towards the improvement of space exploration.

NO CAN BRAIN NO MORE VERSION:

RCS thrusters that use Motor Action as the primary propulsive force. With the Sun or local planetary Geomagnetic field as the 'stator' segment of the motor, and thruster 'coil' blocks as the rotor.

Principle Characteristics of EMRCS Reactionless Thrusters. The primary pros as well as balancing cons.

- No 'fuel' required.

Vessel does not have to carry a limited supply of Monopropellant. This is the biggest advantage. These thrusters NEVER (as far as we're concerned) have to worry about running out of fuel.

- Very Large Power Consumption.

Let's not fool ourselves. Generating an effective magneto-motive force to move a spacecraft massing several tons requires a lot of power. If you're running on solar panels and batteries, you'll be spending a LOT of time waiting for recharges.

- Very Low Thrust Power.

Again, while it holds the promise of near infinite thruster power, the mechanical forces are going to be small. This is NOT a substitute for say, an ion or plasma thruster. In fact, Ion thrusters look like Mainsail rockets compared to an EMRCS.

- The parts themselves will be heavy.

It's wire wrapped around solid iron cores. Does this need to be explained in detail? You aren't saving weight by dropping monopropellant tanks unless they were BIG tanks.

- The parts produce large amounts of waste heat when in operation.

Ohm's law states that current is voltage divided by resistance. Watt's law states that power (heat) is Voltage multiplied by current. Power (heat) thus goes up with the square of the voltage. And for magnetic coils to generate the kind of fields needed to produce appreciable reaction force require a large amount of current, thus, large voltages. Which of course when you sift through all this electronics tripe, simply means that motor coils get HOT. EMRCS is thus understandably very quick to overheat when in use, and require heat sinks/radiators to dump their waste heat.

That's it. That's all there is, there isn't any more. EMRCS, in the concept of game mechanics are simply RCS thrusters in which monopropellant is traded for electrical consumption and the production of waste heat on a 'heavy for its size' part that produces low amounts of thrust.

I thought I'd get this idea out here and see if anyone who models parts wants to give it a crack.

Anyone interested?

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This is a great idea, but to work as described would need a plugin, as the stock engine/rcs modules will not operate on electric charge alone.

There is kinda a way around that without using a plugin, by making a new resource that the engine/rcs burns AND produces (see the firespitter electric props for example of this). What creates this little issues is that the engine/rcs modules need to use at least one resource with mass...electric charge is massless.

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This is a great idea, but to work as described would need a plugin, as the stock engine/rcs modules will not operate on electric charge alone.

There is kinda a way around that without using a plugin, by making a new resource that the engine/rcs burns AND produces (see the firespitter electric props for example of this). What creates this little issues is that the engine/rcs modules need to use at least one resource with mass...electric charge is massless.

So we need to grab a plugin programmer as well? Perhaps we could cannibalize Firespitter's dll.

Alternately, the part produces a resource on its own, stores it, and uses it. (Say, resource named 'magnetic force'. Produces and stores 1 unit that weighs a silly-small amount, and consumes it the same time it produces it.)

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So we need to grab a plugin programmer as well? Perhaps we could cannibalize Firespitter's dll.

Alternately, the part produces a resource on its own, stores it, and uses it. (Say, resource named 'magnetic force'. Produces and stores 1 unit that weighs a silly-small amount, and consumes it the same time it produces it.)

If your gonna do it the non-plugin way your actually gonna want to make the engine produce slightly more of this resource than it consumes. Making it even produce/consume value can create issues, for some odd reason.. but the offset can be minimal.. like 0.0001 is enough to be issue free. And making it super light will work...long as it has some mass its ok.

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Well, this is a good idea, but I think that they shouldn't really heat up much. Those magnets would be pretty much required to be superconducting in order to produce fields of such magnitude. Also, the way I see it, they're only good for translating the spacecraft. Reaction wheels are much cheaper way of producing torque by exploiting Newton's 3rd law.

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In order to keep this 'balanced' it'll require quite a bit of tweaking. Since you don't need 'that much' monopropellant in vehicle anyway, current Reaction wheels basically replace the need for RCS (part from translation). So how 'heavier' would you want it to be in relation to how much RCS fuel you actually need to do what you need to do?

If either the power consumption or weight is too low, then might as well just play with RCS fuel set to infinite.

As KhaosCorp mentioned, you will definitely need to make a plugin for this. But as you mentioned, you can easily peruse the existing code, assuming you know a bit of programming so you can figure out what going on in their crazy source code of theirs. ;)

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As KhaosCorp mentioned, you will definitely need to make a plugin for this. But as you mentioned, you can easily peruse the existing code, assuming you know a bit of programming so you can figure out what going on in their crazy source code of theirs. ;)

I said a plugin can be used....but this could be done 100% without a plugin...just not as smoothly. Stock engine module + stock alternator module is all that's needed to create the functionality.

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I said a plugin can be used....but this could be done 100% without a plugin...just not as smoothly. Stock engine module + stock alternator module is all that's needed to create the functionality.

Ahhh! Yeah, didn't think of using those modules!

Oh well! What do I know. :)

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If your gonna do it the non-plugin way your actually gonna want to make the engine produce slightly more of this resource than it consumes. Making it even produce/consume value can create issues, for some odd reason.. but the offset can be minimal.. like 0.0001 is enough to be issue free. And making it super light will work...long as it has some mass its ok.

I can see that. Program code is executed linearly, so you'd have an issue with an on-again, off-again cycle of thrust pulses that would likely cause a downstream cascade in the physics engine.

As for balancing. That comes with play testing. I know that the magnetic fields involved would be power-hungry monsters. So it's pretty much a given that EMRCS will consume larger amounts of power and require a player to at least set up a decently large vessel. Probably nuclear reactor and radiators minimum... That or some large batteries, very few maneuvers, on a very light vessel. There's tradeoffs for any given design.

But let's not jump the gun too soon. Some the most useful mods I've found are some of the simplest things. Like weighted bricks. Or this electric turbine I came across. (The electric turbine is brilliant even if it's essentially a canibalized turbojet where the guy just renamed it, got rid of all its thrust, and set the fuel consumption much lower. Essentially an aircraft APU.)

Not too flashy, but give it to a guy as another lego brick of sorts, and watch what he does with it. Results can be surprising.

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I can see that. Program code is executed linearly, so you'd have an issue with an on-again, off-again cycle of thrust pulses that would likely cause a downstream cascade in the physics engine.

As for balancing. That comes with play testing. I know that the magnetic fields involved would be power-hungry monsters. So it's pretty much a given that EMRCS will consume larger amounts of power and require a player to at least set up a decently large vessel. Probably nuclear reactor and radiators minimum... That or some large batteries, very few maneuvers, on a very light vessel. There's tradeoffs for any given design.

But let's not jump the gun too soon. Some the most useful mods I've found are some of the simplest things. Like weighted bricks. Or this electric turbine I came across. (The electric turbine is brilliant even if it's essentially a canibalized turbojet where the guy just renamed it, got rid of all its thrust, and set the fuel consumption much lower. Essentially an aircraft APU.)

Not too flashy, but give it to a guy as another lego brick of sorts, and watch what he does with it. Results can be surprising.

Don't get me wrong it's a good idea. Just might be a challenge to balance. :)

I'm all for bringing more 'blocks' for the masses to play with!

I'll be releasing my plugin 'soon' and it'll have a somewhat simple resource generation code, you could maybe excise it from that.

cheers,

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Just wait until I propose fusion torch engines.

Imagine riding on a six-hundred meter space vessel with a 3 km long nuclear exhaust plume coming from five meter wide engine bell magnetically piping energy directly from a miniature sun.

I'm over in the orbital manufacturing thread poking a little at the moment. The stuff I want to add to KSP pretty much involves maturing the orbital building plugins. Because it's kind of hard to design 20, 30, and 40 meter plus sized parts and construct huge vessels if you can't get them into orbit.

Yeah, I want to build HUGE ships. But infrastructure first.

Speaking of fusion torches, has anyone actually done fusion torch engines? Or are we still on orion drive nuclear pulse detonations?

EDIT: Eh, I'll just write some personal notes down on them. Then at least I'll have the idea on record here to refer to later.

Fusion Torch Engine System:

Components:

- Fusion Reactor

- Fusion Torch Exhaust Nozzle (Or Fusion Torch Engine

Fusion Reactor

A fusion reactor works similar to the nuclear reactors. However, a fusion reactor requires an external liquid fuel tank as a fuel source and defaults to a shutdown state.

The fusion reactor requires a large amount of electricity for initial startup. Once the command to start the reactor has been processed, the reactor itself requires five minutes to come up to temp. This means players will have to plan around starting and stopping the reactor. Or just leave it running.

The fusion reactor consumes liquid fuel at all times while active. Albeit this is a very SMALL amount of fuel, there is no throttling.

[[Variation on the reactor, as a bonus, is to have a stage II once the reactor is lit where it can burn oxidizer for a higher amount of energy (and waste heat) output. (But this could be optional)]]

Fusion reactor produces large amounts of waste heat at ALL times if an attached Fusion Torch Engine is not operating at full power. (Much like nuclear reactors and matching nuclear thermal rockets behave.)

Once active, Fusion reactors produce thermal energy, which can be used by a carnot cycle engine to produce electricity, or by a fusion torch engine directly.

Fusion Torch Engine

A fusion Torch engine operates by tapping the fusion reactor, and magnetically piping super heated reactor plasma out the exhaust nozzle at a large fraction of the speed of light. In terms of power and efficiency, it’s got the power of a mainsail engine, with an efficiency surpassing that of an ion engine.

However, it is also the largest, heaviest engine you can get, measuring 3.5 to 5 meters or larger (depending on whether it’s tuned for stock designs, or for modded parts or much larger size), and has a nasty, tempermental drawback.

Most scientists would agree that when you take super-heated nuclear plasma and hurl it out the back of a tube at a decent fraction of the speed of light, that anything that happens to be behind that tube is likely to suffer from a severe case of Not There Anymore. Thus, scientists are obligated to inform Jebadiah Kerman that standing behind a fusion torch engine should be avoided at all costs, lest he suffer from said illness himself. (No really, it’s a really bad disease with no cure. GET AWAY FROM THAT ENGINE!)

Incidentally, it also happens that while you may not think about it, atmospheric gasses are not immune to plasma slamming into it at ten percent of lightspeed. In fact, the chances of the plasma alone causing additional nuclear reactions upon contact with relatively static atmospheric gasses pretty much approach one. So if this engine lights while in an atmosphere, you’re almost guaranteed a nuclear blast to the face. Most scientists agree… That’s not pleasant.

Short version: Fusion Torch engines are as powerful as mainsails, efficient as ions, but are larger, heavier, and will overheat and explode near instantly if lit in an atmosphere, annihilating everything in a 2 km radius. Meaning they are a strictly space-only engine. (Optionally, the direct exhaust plume behind an FTE could destroy other objects up to a km away, making them extremely dangerous to use in crowded space as well.)

As a whole, the Fusion Torch Engine System (Reactor and Engines) is a very POWERFUL engine for late game. But it has lethal drawbacks that prevent players from using it as an overpowered substitute launch engine. It’s meant to be used on large vessels constructed IN ORBIT and act as the main engine of what I like to call Capital Class sized vessels. Its drawbacks change how players have to manage their resources while at the same time, loosening up the player’s options and maneuver budget.

Edited by AdmiralTigerclaw

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I can help you a little, also I would make a suggestion, perhaps for a little added weight (Even more than the coils alone) Add a built-in cooler for the EMRCS, using even more power of course but allowing them to be turned on all day long. Coding wise all you would need to do is +weight, +electric charge used, and remove heat build up. Anyway, as for making them work as you describe this is I think what you would want, with alterations as you see fit. This is copied and altered from regular RCS Blocks.


mass = 2.5
dragModelType = default
maximum_drag = 0.001
minimum_drag = 0.001
angularDrag = 2
crashTolerance = 15
maxTemp = 3600

MODULE
{
name = ModuleRCS
thrusterTransformName = RCSthruster
thrusterPower = 0.15
resourceName = EMRCS
atmosphereCurve
{
key = 0 260
key = 1 100
}
}
//--I cant tell for certain if the generator will stop using power when storage of EMRCS is full, another option would be to make the RCS module above use 2 fuel types however I am not sure if this is possible.
MODULE
{
name = ModuleGenerator
isAlwaysActive = true
OUTPUT_RESOURCE
{
name = EMRCS
rate = 0.75
}
INPUT_RESOURCE
{
name = ElectricCharge
rate = 32
}
}

RESOURCE
{
name = EMRCS
amount = 20
maxAmount = 20
}
}

You may need to alter numbers for balance and to make it work as intended.

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I can help you a little, also I would make a suggestion, perhaps for a little added weight (Even more than the coils alone) Add a built-in cooler for the EMRCS, using even more power of course but allowing them to be turned on all day long. Coding wise all you would need to do is +weight, +electric charge used, and remove heat build up. Anyway, as for making them work as you describe this is I think what you would want, with alterations as you see fit. This is copied and altered from regular RCS Blocks.


mass = 2.5
dragModelType = default
maximum_drag = 0.001
minimum_drag = 0.001
angularDrag = 2
crashTolerance = 15
maxTemp = 3600

MODULE
{
name = ModuleRCS
thrusterTransformName = RCSthruster
thrusterPower = 0.15
resourceName = EMRCS
atmosphereCurve
{
key = 0 260
key = 1 100
}
}
//--I cant tell for certain if the generator will stop using power when storage of EMRCS is full, another option would be to make the RCS module above use 2 fuel types however I am not sure if this is possible.
MODULE
{
name = ModuleGenerator
isAlwaysActive = true
OUTPUT_RESOURCE
{
name = EMRCS
rate = 0.75
}
INPUT_RESOURCE
{
name = ElectricCharge
rate = 32
}
}

RESOURCE
{
name = EMRCS
amount = 20
maxAmount = 20
}
}

You may need to alter numbers for balance and to make it work as intended.

That's nifty and quick of you. But yeah, that'll have to be tested. If it works as advertised, then we don't need to do much else unless someone WANTS to torture themselves making the plugin. We just need someone to design the part model itself.

I'm thinking two part types. One radial, containing five coils around the sides in the four cardinal directions, and on coil on the side that faces away from vehicle center. (Allows one part to have a full six degrees of freedom.)

The second part type being an inline component that's much larger and more powerful. Ringed with coil modules. Perhaps taking a page out of the Alcubiere Drive model from the warp plugin.

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Short version: Fusion Torch engines are as powerful as mainsails, efficient as ions, but are larger, heavier, and will overheat and explode near instantly if lit in an atmosphere, annihilating everything in a 2 km radius. Meaning they are a strictly space-only engine. (Optionally, the direct exhaust plume behind an FTE could destroy other objects up to a km away, making them extremely dangerous to use in crowded space as well.)

What you're describing sounds like IC-fusion engine: http://www.projectrho.com/public_html/rocket/enginelist.php#icfusion It doesn't actually blow up if exposed to atmosphere, so I think that it could be used for ascent. On the other hand, it's a pulse engine, which isn't really an optimal solution, especially in KSP.

However, another viable torch drive is an MC-fusion engine: http://www.projectrho.com/public_html/rocket/enginelist.php#mcfusion Atomic Rockets makes quite a few assumptions about the technology's limits, you could potentially get high thrusts out of this if you manage to scale the engine up. It's also very viable to have multiple versions depending on the tech available, only the last ones being actual torch drives.

Note, the entire concept of a KSP torchship is sketchy at best. If you're running a brachistochrone, you're constantly under thrust, so you can't warp more than 4x, meaning you'll actually wait longer than with a normal transfer orbit.

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Could one use a plugin to make it work better in stronger magnetospheres? Maybe cooperation with the KSP Interstellar mod could help there.

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How would you control the ERCS?

Would it respond to the throttle, or does it behave like RCS?

Or maybe both...

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You could also look over at KSPI. He's got a 'waste heat' resource that you have to radiate out or things shut down (or explode).

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Our sats currently do use earth's magnetic field to move and align themselves, much like a compass. It does not require much power at all, but the field is very weak. it's like using an ion engine.. practically unmeasurably small force is exerted over a long period of time to accomplish movement.

Ramping up the coil power doesn't help, once you max out the force you can push off the planet's field with the rest is just wasted power. Also other planets have inconsistent or totaly missing magnetic fields, so it's really not a good solution for exploratory sats.

http://en.wikipedia.org/wiki/Attitude_control#Magnetic_torquers

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Dropped a note in that thread already, just waiting on a response.

Just a brief reply I'm afraid because I don't have much time right now but Fusion reactors are a planned feature for KSPI. They will require Deuterium+Tritium (or maybe, at some point, Helium-3) and will produce power outputs somewhere between the nuclear and antimatter reactors. These might be restricted to relatively large parts as the DT Vista Inertial Fusion Engine already is, though I'm more thinking about 2.5m+ in this case.

If you're looking for torch-ship like perfomance then the DT Vista is probably still the place to be because you have the variable specific impulse throttle on that engine. The fusion reactors and associated thermal rockets will most likely be for slightly higher thrust applications/lower specific impulse applications. That said, these fusion reactors/generators would be excellent for actually powering up the DT Vista.

Note that that engine already poses a radiation hazard to other nearby ships.

Additionally, electrical RCS is also a planned feature though is very unlikely to appear until at least version 0.9.

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