Full Power to Shields

[Knight26]

Ok, here is the situation. While I am waiting to hear back from the publishers I am in a writing standstill. I don't want to write anything new or do any revisions just in case I have to revise the first book again, since any revisions tend to snowball. Therefore I am working on the tech aspects, setting up the universe and its rules. Now things I already have down and have beaten from every angle I can think of include, propulsion systems, FTL travel (hyperspace, with a coherent scientific theoritical base behind it), artifical and anti-grav creation, energy production, biological considerations, sensors, communications, psi, weapons, and a few more I can't think of right now. But one I have not put too much into yet is now making me scratch my head, Shields. Armor I'm getting close on, researching various emerging armor technologies and some of those used by other sci-fi authors and games I've got in my head a good armor system to use. But... Shields are a different matter. I'm trying to keep this somewhat hard sci-fi, ok maybe frozen jello, but not liquid like say SW, and I want to have a shielding system that once explained somewhere will actually make someone who is a scientist go, "hey that might just work." Therein lies the problem, the few shielding systems I have been able to research either have too little info on how they work, i.e. purely handwavium (SW, most games, EE Doc Smith, etc...) or go all the way to your Niven type that are all but impractical (screens that aborb all energy making them in invisible on both sides). I don't want to outright copy another system that is out there and right now the best I can come up with is some type that uses a ship's grav/anti-grav and or some form of electromagnetics, or possibly plasma screens (which are being developed). So what I am asking is what are your ideas, or what shielding systems have you read about in the past that seem plausible given the right tech level that can give me a good starting basis? I will of course keep you all apprised of what I eventually come up with.

[mechaninac]

How about:

A coherent energy field consisting of negatively (or positively) charged particles trapped within a magnetic field around the ship in the shape of a torus. This would be akin to Earth's own Van Allen's belt. If the magnetic field is strong enough, and the particles suspended within kept in a sufficiently energetic state (in constant motion around the field at near relativistic speed), than the shield would be capable of protecting the ship from most radiation and energy weapons, and would play havoc with the guidance systems of missiles and mines that get anywhere near it. However, this type of barrier would be near useless against kinetic weapons such as rail gun fired projectiles.

[Knight26]

Not a bad idea, I was considering dual shield layers, one for energetic weapons and one of kinetics. I just wonder how effective it would be against even energy weapons, like plasma lasers, but so long as it absorbs/deflects most of the energy then it should be ok. Of course it also has to allow for visible light and the sensor/comms to get through.

[Cruel Angel's Thesis]

Well if you have the gravtional stuff on the ship you could use it to generate gravity wells outside the ship. Enegry weapons will be warped away/around the ship. Kinetic weapons will be affected as well. Enemy ships will have certain sensors affected due to the gravtional distortions. You sensors will be affected, but you have sensor windows (yes i know its a Star Trek answer) that can be opened and used. However the enemy might pick up on those and fire a weapon through it (like shooting down a snipers scope), so having the sensor windows moving or you open and close them once you get intel. However the distortion will effect your weapons as well, so you can fire out of the sensor windows (something never covered if your shields protect you how do you fire out them since your weapons will be effected as well).

Realstic sci-fi shields are always difficult to do since you have to use something to makes sense, but you always fall back on Gene Roddenberry's answers. "We don't sit around explaining how a car works, why would they be doing that in the 24th century." And there is a axiom for anime, "Unexplained tech is better then stupid tech."

Now in Warhammer there is something called void shields so you might want to look at those, not sure of the sci-fi level in warhammer, but you might find something.

Cruel Angel's Thesis

[mechaninac]

Kinetic weapons could be handled with ablative armor. This type of shield would be most effective against charged particle beams, plasma weapons, or anything that uses ions, electrons, positrons, etc. Anything with an inherent charge would be caught in the,and dissipated by, the magnetic field of the shield, creating an Aurora like effect at the shield's poles.

Visible light should have no problem getting through this type of shield... it may be distorted by the lensing effect caused by the magnetic field, but that could be compensated by adaptive optics sensors. Consequently, light weapons, from IR to UV lasers would not be affected much by an electromagnetic shield unless the particles riding within the field are geared towards absorbing specific spectrums of light.

Comm signals may be a bit more problematic; but since, like light, they consist of electromagnetic waves, they should be able to slip through, specially if they are modulated to a special shield neutral frequency.

Sensor beams, other than electromagnetic (see comm signals), would be blocked by your own shield since anything that would cripple your opponents beams would also affect yours; unless, similarly to the comm frequency loophole, your sensor wavelength is neutral to the absorption properties of the particle stream within your barrier.

Thinking about this stuff is beginning to give me a headache.

Edited January 17, 2007 by mechaninac

[Knight26]

The torus shape may cause a problem though, it would leave you back and belly exposed, but it is a good starting point.

[Cruel Angel's Thesis]

About generating a smaller torus to protect the back and belly?

Cruel Angel's Thesis

[VF-19]

Well if you have the gravtional stuff on the ship you could use it to generate gravity wells outside the ship. Enegry weapons will be warped away/around the ship. Kinetic weapons will be affected as well. Enemy ships will have certain sensors affected due to the gravtional distortions. You sensors will be affected, but you have sensor windows (yes i know its a Star Trek answer) that can be opened and used. However the enemy might pick up on those and fire a weapon through it (like shooting down a snipers scope), so having the sensor windows moving or you open and close them once you get intel. However the distortion will effect your weapons as well, so you can fire out of the sensor windows (something never covered if your shields protect you how do you fire out them since your weapons will be effected as well).

Realstic sci-fi shields are always difficult to do since you have to use something to makes sense, but you always fall back on Gene Roddenberry's answers. "We don't sit around explaining how a car works, why would they be doing that in the 24th century." And there is a axiom for anime, "Unexplained tech is better then stupid tech."

Now in Warhammer there is something called void shields so you might want to look at those, not sure of the sci-fi level in warhammer, but you might find something.

Cruel Angel's Thesis

The nasty problem with gravity shields is the question on how you prevent tearing your ship apart.

A neat benefit of the shield is that you could trap lots of kinetic rounds in it, forming an outer skin around your ship. Of course, you might have trouble seeing out the window with millions of bullets in front of it...

Personally I'd go with the Homeworld route. Lots of ablative armour. To hell with shields!

[drifand]

Try 'mirror fields' like those in the 'Culture' novels by Ian M Banks. The sentient AI controlled megaships had 'effectors' that could do just about anything with magnetic fields: Displace (teleport) matter/people/weapons; Scan/'feel' volumes of space/matter to seek out specific objects; Grip the hyperspatial energy grid for motion/FTL travel; Manipulate less sophisticated machinery/computers; Generate an englobing field that is mirror-surfaced to almost all frequencies of light, etc

No need to explain everything, if the storytelling is great it'll be believeable! :-)

In fact, one of my favorite Culture novels is told from the POV of a technologically backward race being manipulated by these well-meaning, meddlesome AIs and their human charges. To the swords 'n' sorcery inclined people of the planet, these interlopers with advanced medical/military knowledge, emergency backup semi-sentient micro weapons etc were really MAGIC. Only the fans/readers could see the 'truth' and enjoy the story doubly well.

Edited January 18, 2007 by drifand

[Mr March]

That must be Inversions, I think it's the only Culture book I haven't yet read.

[Graham]

I'm also a big fan of Iain M Bank's Culture novels, but their Effector technogy is probably a bit too advanced for knight26's ships, at least from what little I know about his ships (they look sorta old style Flash Gordon-ish to me). He's also stated that he does not want to directly copy shield tech from any source.

Personally, if you want to make it a realistic hard sci-fi universe, I'd stay away from any sort of energy shields, and instead go with physical armor (reactive, ablative etc). Point and medium range defence with lasers, railguns, missiles etc and active and passive stealth technology for avoidence.

Another possible anti-laser defence could be sounding the ship with ablative anti-laser particles (sorta like chaff). In the old Traveller RPG, this was called 'Sand'.

Graham

[Retracting Head Ter Ter]

The problem with using the term 'Force _Field_' is that unlike common movie interpretations where the incoming shot seems to hit an invisible wall, a field should dissipate the incoming shot over a distance.

Do you want the 'shield' to be a 'wall' or a 'field'?

How about doing away with shields and have energy reinforced armour? You know, like in Macross Zero. Something along the lines of pumping energy to strengthen the molecular bonds of the armour material. Not sure what happens to the incoming energy then, lots of dissipated heat I guess.

Edited January 18, 2007 by Retracting Head Ter Ter

[Morpheus]

What about Tesla shield?

http://www.cheniere.org/books/part1/teslaweapons.htm

The Saryshagan howitzer actually is a huge Tesla scalar interferometer with four modes of operation. One continuous mode is the Tesla shield, which places a thin, impenetrable hemispherical shell of energy over a large defended area. The 3-dimensional shell is created by interfering two Fourier-expansion, 3-dimensional scalar hemispherical patterns in space so they pair-couple into a dome-like shell of intense, ordinary electromagnetic energy. The air molecules and atoms in the shell are totally ionized and thus highly excited, giving off intense, glowing light. Anything physical which hits the shell receives an enormous discharge of electrical energy and is instantly vaporized -- it goes pfft! like a bug hitting one of the electrical bug killers now so much in vogue.

Its kinda difficult to tell whether the above article is fact or science fiction.

Edited January 18, 2007 by Morpheus

[Akilae]

Let's take this back to the basics.

There are two basic functions of armor which I think should also apply to shields: absorption, and deflection. The first is usually performed by the structure of the armor, the second by the shaping of the armor. Unless you're talking about something exotic like reactive armor... but let's keep this simple. In the history of tank armor evolution has been in leapfrog phases. First metallurgy was superior enough to produce metal that was better at absorbing damange, then the Russians came up with sloping armor, then the Brits came up with Chobham... etc...

So what do you want your shields to do? What stage of evolution do you want them to be? If you want them to absorb, then what's the absorption limit? What do you want to apply this armor to? Small craft? Large craft? The needs of each will be different. Also think about the culture that developed the armor. Each country on earth has different tank and armor designs based on their fighting philosophy and weapons.

For the ultimate in "armor" technology, I think gravity will reign supreme. The design here will be based solely on deflection, instead of absorption. Imagine what light does when it passes by a massive gravity well and you'll get a pretty good idea why. Now reverse that effect. For better visual effects, the final few episodes of Diebuster has a STMC deflecting incoming optical based weaponry using gravity. But this is also pretty exotic stuff... to generate gravity wells massive enough to matter you'd need to harness the power of a mini black hole. On the flipside, in order for the enemy to even touch you they'd have to throw something even more massive at you.. say.. a few planets worth

The problem is what happens when you power up your shields? Well, I'm not sure if the effects will mimick a black hole, but you WILL be flying blind, literally, given the effects of massive gravity wells on light... heck, reverse the effects of your shields and you won't even need shields, just open up a black hole in front of you and suck your enemy into oblivion. End of story :-p

In terms of practicality, as somebody else already mentioned, lots of ablative armor. You can even go ST: Enterprise on it and pass some sort of EM current through your armor plates.

Edited January 18, 2007 by Akilae

[F-ZeroOne]

Going abck to armour rather than shields, a while back it was announced that military researchers in the UK (yay, us!) had developed a way of passing an electrical current through armour plate that could break up incoming shells before they could detonate.

Other than that... er... Minovsky particles?

[Knight26]

I really like Mechaninac's idea with an artifical van allen belt and have some ideas springing from it.

Type 1 Shield: Electro-Magnetic Toroid (EMT): Effective against energetic weapons. Long used in the creation of fusion energy the EMT also referred to as a mirror field was developed by studying the natural E-M belts present around most life giving planets. These shields work by creating a coherent energy field consisting of negatively (or positively) charged particles trapped within a magnetic field around the craft in the shape of a torus. The suspended particles are kept in a constant EM controlled loop around the craft at near relativistic speeds. The initial benefit of this is clear, as it protects the crew from harmful stellar radiation, and this was its original usage. It was later discovered that the field could also protect against energy weapons, deflecting or absorbing most of the energy, and played havoc with weapons guidance systems. The field is further enhanced by being kept in a constant longitudinal or lateral spin, .i.e. the whole toriod rotates around the ship peridocially to cover the gaps left by the toroid. This rotation is imperceptible to outside observors and is synchronized with onboard, sensors, communications and weapons to ensure that they will only transmit or fire when the toroid is in a non-interfering region. The system is not effective however against kinetic projectiles which pass through it harmlessly, however it will result in early detonation of any unshielded explosive ordnance.

Type 2 Shield: Gravitational Deflectors: Ever since the first Anti-Gravity Gield (AGF) generator was developed scientists realized that not only could it be used to float an object but to protect it from kinetic attack. Graviational Deflectors work by focusing the influence of an AGF towards an incoming kinetic projectile. The difference in graviational potential effectively "pushes" agains the projectile, slowing it and or deflecting it away. It should be noted that the greater the angle of incidence that an incoming kinetic weapon comes in at the great the amount of energy required to slow or deflect it. (I'll draw diagrams). Gravitational deflectors require much more power to operate then EMTs and as such are primarily used by large scale craft and installations. Smaller scale craft however that cannot afford the power requirements instead used focused AGFs which are automatically controlled by onboard computers, focusing the AGFs towards incoming fire. Graviational Deflectors are most effective against Kinetic weapons, but have also proven marginally effective at deflecting energitic weapons as well.

[Knight26]

So basically we have two types of shields on pretty much all craft, your EMTs which protect against energy weapons, and your GDs, which protect against kinetics. The EMT is much more of a field and absorbs/deflects the energy, but in the process the electron cloud loses potential and requires time to recharge. The GD is also a field but is pretty much a pure deflector, hit it spot on and it just pushes back trying to through you, hit it at an angle and you bounce right off. There is no real shield loss there, but the shield can be quickly overwhelmed if you keep hammering it eventually frying the projector. Plus, since it more focused, especially on fighters, you best bet is to attack from multiple angles and hit several areas at once, the more the field is expanded the less effective it is. Of course since most fighters have multiple banks of AGF on their ventral surface it is more advisable to attack from above.

So how do those two concepts sound, especially since they will be used together?

Also note that the EMT uses real mirror field theory, which from what I was able to gather was Iain M. Banks starting point for his Mirror Fields. Basically scientists have been trying to utilize them for years to make fusion.

@ All: Armor is still used, I will expand on the types used later.

@Drifand: I looked up mirror fields and expanded on the real practice of them to expand on Mechananics concept, good idea, and as soon as I saw it I remembered my classes on fusion and nearly smacked my head off for not thinking of them sooner.

@Graham: I think that real shields could be developed some day and part of hard sci-fi is expanding on existing theory. Flash Gordonish? As for the dust shields of traveler, looked into it, but rejected it, too many issues.

@RHTT: Basically these are fields as described above.

@Morpheus: Ah good old Tesla

@akilae: You basically just described the Langstron Field, Larry Niven loved 'em, but black hole ships, no thanks.

[Knight26]

I promised some diagrams, here are three that show how a GDF would function:

[attachmentid=39697] Against a direct hit.

[attachmentid=39698] A deflection hit.

[attachmentid=39699] A breaching hit.

Edited January 18, 2007 by Knight26

[Nied]

Are the GDs necessary? Since most kinetic kill weaponry would be ferrous anyway (especially if fired from a rail gun) wouldn't a magnetic field as powerful as the one you're talking about trap or alter the course of a KE projectile? At the very least you'd expect it slow down a ferrous KE weapon limiting the amount of damage dealt. The only problem with this is that the KE from projectile weapons would be transfered to the shield generator so it would have to have a heavily re-enforced mount, this might be easier than armoring a whole ship though.

[Knight26]

You know Nied something was bothering me and I think that was it. But I think that you would still want to keep the GDF for use against other projectiles, like missile warheads, rocks, etc... At a minimum you would want to keep them as some form of (and I hate to phrase it this way) navigational deflector. Anyway I think that the kinetic shock from the hit will end up getting transferred with any of these shields, so yes some reinforcement will be required.

Edited January 18, 2007 by Knight26

[Knight26]

Ok how about some EMT diagrams now. Yes I am bored at work today (your tax dollars at work folks).

[attachmentid=39700] First up the basic EMT arrangement around the ship.

[attachmentid=39701] Second up the direct hit absorbtion effect.

[attachmentid=39702] Third the deflection hit absorbtion/deflection.

[attachmentid=39703] Last up the breeching hit.

Notice the kinetic effect transfers through this field. I need to sit and think it if will pass through the GDF too, I'm not sure, part of me says yes, the other part says it will be absorbed.

Edited January 18, 2007 by Knight26

[Knight26]

Ok based on everyone's comments I think I have my shields figured out, thanks a lot. I even did a full write up on it complete with corrected and refined diagrams. If anyone who provided input wants to take a look let me know.

[Retracting Head Ter Ter]

How do these shields affect outgoing fire though? Does fire control have to lower them for a moment to let attacks go out?

[Knight26]

The EMT spins at a known set speed, the weapons just have to be time to fire when the EMT is out of the way, kind of like the guns on prop planes. As for the GDF that is a focused system, it is not up all the time, think something like the pinpoint barrier of the Macross, in simple terms, due to energy requirements it is only projected into the region it is needed, when it is needed.

[chrono]

That must be Inversions, I think it's the only Culture book I haven't yet read.

Actually most of Bain's books have that element in them in some way any how. Remember his stort story works?

As for Effectors I'm beginning to think that those are basically advanced and realistic usage of virtual particles

Knight26,

You are digging your self a fairly nasty little hole that will trip you up later on.

[Knight26]

how so?

[Knight26]

Since there were questions about it, here is my armor description, comments:

The outer layer of all starships be they combat or non-combat, must provide defense against artificial and natural threats. For primitive races this armor usually takes the form of heavy plate metals attached to the outer hull of the ship, however these armored plates add a significant mass penalty to any ship and are not considered viable options. Armor still takes many forms but the most common type of armor found on combat and non-combat starships is found described below:

Outer layers of hull armor are typically composed of multiple layers of nanosheet, nanosheet is a thin sheet made from nanotubes which are 250 times stronger than steel and 10 times lighter. Nanosheet is ideal for use in the outer layers of hull armor for the following reasons:

• As one of the most thermally conductive materials known, nanosheet lends itself to the development of heat sinks, and in the case of space craft, nanosheet armor is often used to supplement or completely replace traditional thermal radiators.

• Because it has an unusually high current-carrying capacity, a film made from nanosheet allows for electrical energy from electrical discharge strikes or energy weapons to flow around the craft and dissipate without causing significant damage.

• Films of nanosheet have also proven itself to be able to effective protect electronic circuits and devices within ships from electromagnetic interference, which can damage equipment and alter settings. Similarly, such films allow military craft to shield their electromagnetic "signatures," from conventional electromagnetic radars.

• When layered correctly nanosheet makes a highly effective anti-ballistic armor plating.

The layers of nanosheet act as an extremely hard outer layer, and as a very effective conductor of heat and energy. Impacts from energy weapons typically dump their energy into the lattice matrix, which then spreads it across a much wider area via conduction. However the lattice can be breached if enough energy is released into it because it will disrupt the atomic linkages of the carbon nanotubes.

Beneath the nanosheet layer and the main armor lays a network of fiber sensor and microtubes known as the self repair sheet. The microtubes are in turn lattices nanotube constructs with numerous opening through which an army of carbon construction microbots reside. These tiny microbots, once activated seep out of the microtubes and repair any damage to the outer layers of armor detected by the fiber sensor grid.

The final layers of the main armor lie beneath the self repair sheet. The main armor is composed of varying layers of high density composite closed metal/ceramic foam arranged in ablative sheets. The metal used in the foam can take many forms but is usually an aluminum/titanium composite. This lightweight structural material has proven itself time again to be extremely stiff and rigid and highly resistant to impact, though high velocity ballistics will permanently deform it upon impact, mandating its replacement. The armor is cast in such a way that the material density increases as it nears the inner wall, shrinking the size and number of foam pocket and making the material more solid. This makes the material highly resistant to impact and penetration. Additionally the armor is always forged in a nitrogen rich environment with the purpose of trapping nitrogen in foam pockets. The addition of the nitrogen in these pockets gives the armor additional resistance to energetic weapons that penetrate the nanosheet layers, which vaporizes the trapped nitrogen blowing the melted hull metal outward. The resultant spray of metal particulates has the added benefit of disrupting the cohesion of any additional incident energy further protecting the hull for a short period.

In addition a nanotube lattice is woven throughout the closed metal/ceramic foam. In the event that a ballistic impact has enough force to fracture the hull armor the nanotibe matrix is normally strong enough to hold the damaged sections together.

Edited January 22, 2007 by Knight26

[Mr March]

Actually most of Bain's books have that element in them in some way any how. Remember his stort story works?

Perhaps a small element in the stories, if you're refering to less advanced societies The Culture interacts with (more specifically, Contact). But from the description it sounds more involved than that, so I was thinking it was one of the few Culture books I've not yet read. I think the only one I've not gone through is Inversions. Consider Phlebas, Player of Games, Use of Weapons, Excession, State of the Art and Look to Winward I've all read.

[Mr March]

I'd very much agree with Graham. Sometimes intriguing concepts can come from what seems like the most mundane technology. Try advancing current technology forward while keeping the fundamental technology the same and see what you get. It might be pretty damn cool. Take gunpowder ballistics, a technology that's been around for hundreds of years yet we're still using it. What happens if your future technology can get bullets and shells going tens of thousands of meters per second rather than just the few thousand we're limited to today? How about faster, maybe even minor fractions of the speed of light. That would make quite a deadly weapon and its far more plausible than some phasing energy nonsense.

Also, I'd do research and concentrate on real terminology. Proper use of scientific and astronomical terms like kiloton (for measurable explosive yields) or light minute (a much more relevant method for distances in space) can bring a great deal of legitimacy to any science fiction story. Especially since so much science fiction doesn't even use proper terms or invents ridiculous fictional names when they are not needed. You don't need a character to explain a city was destroyed with a 1,000 babbleton explosion when you can just have them use 25-50 kiloton bomb to achieve the same result. Even Macross is guilty of this, using ridiculous distances like Misa quoting 280,000 kilometers for enemy distance when a simple term like one light second will do. You'd be surprised just how much real world science can be written into sci-fi if one just does a little research.

Personally, if you want to make it a realistic hard sci-fi universe, I'd stay away from any sort of energy shields, and instead go with physical armor (reactive, ablative etc). Point and medium range defence with lasers, railguns, missiles etc and active and passive stealth technology for avoidence.

Edited January 23, 2007 by Mr March

[mechaninac]

The way I had the shield envisioned, the toroidal shape would not be all that vulnerable to a coaxial attack angle as the small ID of the torus would be very small and very hard to breach with anything but an attack from directly above/bellow the emitters. See attached image for a shield schematic.

[attachmentid=39810]

Edited January 22, 2007 by mechaninac

[Knight26]

I'd very much agree with Graham. Sometimes intriguing concepts can come from what seems like the most mundane technology. Try advancing current technology forward while keeping the fundamental technology the same and see what you get. It might be pretty damn cool. Take gunpowder ballistics, a technology that's been around for hundreds of years yet we're still using it. What happens if your future technology can get bullets and shells going tens of thousands of meters per second rather than just the few thousand we're limited to today? How about faster, maybe even minor fractions of the speed of light. That would make quite a deadly weapon and its far more plausible than some phasing energy nonsense.

Also, I'd do research and concentrate on real terminology. Proper use of scientific and astronomical terms like kiloton (for measurable explosive yields) or light minute (a much more relevant method for distances in space) can bring a great deal of legitimacy to any science fiction story. Especially since so much science fiction doesn't even use proper terms or invents ridiculous fictional names when they are not needed. You don't need a character to explain a city was destroyed with a 1.000 babbleton explosion when you can just have them use 25-50 kiloton bomb to achieve the same result. Even Macross is guilty of this, using ridiculous distances like Misa quoting 280,000 kilometers for enemy distance when a simple term like one light second will do. You'd be surprised just how much real world science can be written into sci-fi if one just does a little research.

I understand where you are coming from, and the actual write up I did is a much more legitimized document. Also look at the armor write up I just posted. Everything on there is real world tech just taken to the next level. My "nanosheet" is known today as buckypaper, if you look it up on wiki you will see I lifted a lot of stuff right off of it. The same goes for the metal foam, I just made it composite with ceramics. The My changes to mechs torus shield were done as a comprimise to make it more practicle, no offence mech but in order to use energetic weapons with yours tuning would be much more difficult issue. Then you have mirror fields, which are real and in development for use in fusion powerplant, these are the true core of the EMT, and several papers discussing mirror fields have put forth the idea of using them as some sort of at least radiation screen. And again the first generation plasma shields currently in development by the military use the same prinicipals as my EMT, I'm just taking it to the next level. Really the shield that uses the most handwavium is Gravitational Deflector, but even that I have used actual scientific theory on anti-grav, researching many papers, it just took me asking here to really get my brain to wrap all the various scraps together. Yes I have done my homework, helps when there is so little to do at work, lol.

[Knight26]

The way I had the shield envisioned, the toroidal shape would not be all that vulnerable to a coaxial attack angle as the small ID of the torus would be very small and very hard to breach with anything but an attack from directly above/bellow the emitters. See attached image for a shield schematic.

[attachmentid=39810]

Biggest problem I see with that is how to fire the weapons through it, and you have the EM field of the inner wall of the torus running right through your ship. That EM field would reek havoc on unshielded electronics and the fact that you have high energy particles runnign through it could injure personnel as well.

[mechaninac]

Firing weapon's through the shield would be dependent on the type of weapon in question: Kinetic weapons would suffer no effect incoming or outgoing; light weapons would not be deterred by the EM field but would be vulnerable to the charged particles riding within it unless the frequency of the weapon's discharge is set to a one that is shield neutral (the particle within the field would have a known spectrum absorption signature that could be circumvented by setting your laser spectrum to one that is not absorbed by the shield); energy weapons would require a shield flicker in order to be fired (the shield is disengaged for the split second necessary for the charged energy bolt to clear the field effective area -- the energy weapons would be tied in to the shield systems to make the process automatic and seamless).

There would be no problem with the shield intersecting the ship as the generator is fully shielded and positioned so that shielded access corridors connecting the prow and stern of the ship could ferry personnel to either side of the generator. These corridors would not even come into contact with the EM envelope since the part of the filed that intersects the ship is very small in diameter and fully encased within the confines of the shield generator itself (see attached).

[attachmentid=39829]

Edited January 23, 2007 by mechaninac

[Knight26]

I see where you are coming from MM but for I still think that the spinning torus is the better way to go, true it has more moving parts, but overall works better in my mind for the following reasons.

Kinetic projecticles, if of fereous or otherwise EM charged nature (such as from a rail gun) will have their trajectories altered passing through the field, especially if it is always on. I really don't use light weapons so that is not much of an issue and in the right up I note that while the field dissipates charged plasmas in a laser beam the light itself still strikes hull, which many crews find disconserting. As for timing the field with a flicker rate, or just a temporary drop for shooting, you just seriously amped up the power requirements there. Plus you are forgetting about missile weapons, even with the spin the missiles will have to have some shielding during launch to protect them from the launching ship's fields. True the shield could be flickered off (in your case) or the field rotation temporarily slowed (as in mine), but some EM shielding will be necessary, even if it is just temporarily shutting off the tracking systems during launch.

As for getting the crew around. Unless I am misreading my research on mirror fields and van allen belts the charged particles are not in just the outer sheaths, but fill it. So you will still have charged particles running all through your ship. Even if the particles and EM radiation are confined to the sheath, those sheaths still intersect your ship. So now you are talking major masses of addtional EM shielding to protect not just your electronics but the crew. Even if the sheath is only say 1 meter thick, you have a big arc of it running through your ship, at a minimum of two places per deck.

[Knight26]

This should illustrate one of the concerns I have with how you have your torus interacting with the ship MM. Now, this is assuming that the EM field and and charged particles are only in the outer walls of the torus, which I do not think is correct. Here is a deck say three decks above your generator and aft of it. The green arc represents the inner wall of the torus field. Notice that it crosses two main passageways, completely fills a crossing passageway and inpinges on two rooms. And this is only a 1Meter wide field wall, you now have to shield everywhere that the field is touching, plus more in case of fluctuations in the field or risk frying your electronics and steralizing your crew.