Questions about shields

[Purple]

I got this idea from an old thread here. Can Star Wars ships destroy Star Wars ships? And I want to expand upon it. In particular, how to hell would it work on ground vehicles. But I don't want to do a necro. Hence, this thread.

In short terms, the shield of a vehicle works like a magical force field absorbing energy from enemy weapons and channeling it into a set of batteries/capacitors. Than, these capacitors bleed that energy off slowly in some way over time at a safe rate. Now in space there is no dilemma but what about on the ground. Say you mount such a shield on a tank. What would be the best way to dissipate this energy? I was thinking of just converting it to electricity and using the tracks as a ground wire to slowly bleed it off. But I don't know if there are any other better options. Also, what would be the rate of dissipation that could be reasonably maintained before the effects start equaling a tank shell exploding under the tracks. Like, for comparison a sabot round for a 120mm gun carries something like 15-18 MJ of energy. I can't imagine it would be fun to dissipate all that in a few seconds under the tank. But what would be a safe rate?

Also, any comments are welcome.

[Stark]

Since the output required would produce giant white-hot emitters, and fans decided they used neutrino radiators (ie, radiating the heat in particles that are non-interactive), wouldn't that work on a planet?

Using the tracks as a radiator sounds like a great way to fuck up whatever your tracks are made of.

[Samuel]

I think they had a varient in Ringworld, where they had superconducting wire and had one end in the ocean. The end result is it used the ocean as a giant heat sink. I'm not sure if that is possible with real world physics/materials.

[Imperial528]

Well, in the case of Star Wars they apparently use neutrino-based radiators on star ships, so I see no reason why they couldn't do that for tanks and the like.

Now, as for your suggestion, I would say that you really only run into problems if the tank is fighting in some sort of installation where grounding through the floor would not be a relatively harmless event, since it could damage the installation. In the open field, assuming it isn't near anything or anyone and the discharge is not too concentrated you shouldn't have a problem. If the discharge is too energetic you may have the problem of lighting whatever flora that is beneath you on fire, but if that sort of energy is being thrown about that would be the least of your problems.* Personally I would much rather radiate the excess energy as heat instead of electrical bleed off. Although if you really want to go with electrical discharge I would suggest instead of a constant current bleed-off a series of controlled static discharges, since that at worst would just zap whatever is below the tank. Also, I would just place electrodes on the bottom of the vehicle, rather than using the treads to do it.

If you're really feeling ambitious though you could use the shield discharge to recharge your batteries, or use the discharge banks as secondary batteries even.

*Assuming flash-ignition of grass and undergrowth beneath the tank, since presumably the high-energy discharges would not last long enough to achieve combustion of plants under the treads such that an actual fire would be created, and would only light enough to cause a self-sufficient brush fire in dry conditions or the event of an unusually high discharge.

[Purple]

One reason why I was considering a fast power discharge is becouse I want to power my cloaking system on the same idea. The idea for the cloak is analogous to the one for the shield. Both would take energy and dump it into a set of batteries. In case of the shield that energy would come from enemy projectiles. In case of the cloaking device it would come from converting the emissions my vehicle puts out or reflects like heat or radar reflections. That way I can have both shields and a cloaking device (separate systems, same battery) that do not violate conservation of energy.

And yes, I would be using the batteries to power all my tanks systems. But even so, I expect they would be filled up faster than they are drained.

Also using heat as the discharge medium is not an option. That would ramp up the tanks heat signature so much it would make it easy pray for enemy weapons. I figured with electricity I could get to a low enough rate not to make this happen. But like, what is that rate?

[Number Theoretic]

If all that energy is available for you in form of electricity, couldn't you just use it for your weapons? Lasers, railguns or coilguns require insane amounts of energy anyway, so those would be a prime candidate to dump your shield energy into.
As for capacitors, i believe you can assume that a capacitor bank with a mass of 1 ton could store the energy of even several shots, assuming perfect or near-perfect conversion efficiency. A carbon nanotube capacitor can possibly store 60 Wh of energy per kilogram, that is 216 kJ if my math-fu is correct. Multiply by 1000 to arrive at the 1 ton capacitor bank assumed earlier, you have an electric energy reservoir for 216 MJ. Enough for 10 120mm tank sabot hits with 18 MJ each.

[Purple]

I considered that as I said above. The thing is that during cloaked mode the batteries would have to spend hours or maybe even days quietly absorbing energy readings in the KJ range.* And that would mean that when I decloak to fight my capacitors would be near full. Now that is great if I want to fire my weapons in a broadside but very bad if I take a hit or two and my shield batteries are bursting full. So I need a way to bleed off said energy when entering combat to get the thing down to a safe to use level.

*I figured that was about as much as a tank that is only moving around and not firing would put out. Correct me if I am wrong.

PS. Thanks for the interesting article and numbers.

[Imperial528]

Just have a deployable electrode that will ground the capacitor banks. Depending on how large your bank is you may make a small lightning strike below the tank.
However if your capacitors are designed for gradual release than you wouldn't have that.
Heck, maybe just put a grounding rail that skims the ground at tread level, which is better than using the actual treads as the grounding mechanism. Frankly though I would just have a bunch of radiators with heater coils running through them to remove the energy. Then we don't have to get into the safety issues of discharging large amounts of electricity in a combat zone.
Or you could just fire the first shot, that will discharge it nicely. Although that is more a doctrine issue than a technology one.

[Purple]

Hm... can anyone actually suggest any numbers on how much energy is emitted from a tank idling or doing non combat things like just driving around per unit of time?

Also, as I said before heat discharging is not an option unless I want my tank to permanently become a massive IR flare for enemy missiles. Also, I want to use this system even when not cloaked to absorb engine heat, coilgun heat and give me a level (not full) of radar and IR stealth. True cloaking would even cover visible light thou so I figure that would be much more energy intensive.

[Number Theoretic]

This depends on several parameters you need to fix before doing some calculations. Like for example the power consumend by your motors and the rest of the electrical equipment and if you have an active power source aboard (like a gas turbine or, since we are talking science fiction, a small fusion reactor). If you have decided on power consumption and start with a given charge of your capacitor bank, you can solve that for time to obtain the total time your capacitors last until they need a recharge.
Say, for example, your engine is electrical and consumes 11 MW of power (which is a typical value for modern-age battle tank engines, feel free to modify). Let your capacitors be charged with aforementioned 216 MJ of electrical energy. 1 Joule is 1 Ws, so 216 MJ is 216 MWs.
To obtain the time for which your capacitor bank can supply the engine running at full throttle with power, simply divide:
216 MWs / 11 MW = 19 s
So, these capacitors can move you for 19 seconds. Conclusions: You definitely need a gas turbine or a fusion reactor to move your tank in general, but if your motors are electrical, you can simply dump the capacitor's energy into a violent acceleration start of your tank. Don't forget to switch the power source after said 19 seconds or you will be mobile as a rock

[Number Theoretic]

sry for doublepost but somehow i can't find the edit button Oo?

Forgot to post a link to an on-line energy/power calculator

[Purple]

Thanks for the input. For the engine, I was definitively thinking something not that much stronger than modern tanks. Taking your number of 11MW I say that 20-30% more than that should be more than enough. After all this thing does not have to fly or hover or anything. As for the thing it self I was definitively looking at a chemical engine, maybe some sort of futuristic fuel cell but definitively not something as far out as fusion. The thing would still be recognizable to us today in that it produces power but also guzzles fuel and makes a lot of wasted heat. The power would be routed into a generator (unless its a fuel cell where that would be redundant) and run through an electric motor with a fully electronic transmission (no more gears to break). As for the waste heat from the process my cloak would conveniently absorb that heat and recycle it into the batteries thus giving me extra fuel economy.

This said, how do I estimate the power consumption of the various components of the thing? You seem to have a way of finding the numbers that I don't. What's your secret?

[Lord of the Abyss]

sry for doublepost but somehow i can't find the edit button Oo?

Editing in this subforum has a time limit, something like 5 minutes. While it's allowed, the Edit button is at the upper right of your post next to the Quote button.

[Number Theoretic]

Thanks for the input. For the engine, I was definitively thinking something not that much stronger than modern tanks. Taking your number of 11MW I say that 20-30% more than that should be more than enough. After all this thing does not have to fly or hover or anything. As for the thing it self I was definitively looking at a chemical engine, maybe some sort of futuristic fuel cell but definitively not something as far out as fusion. The thing would still be recognizable to us today in that it produces power but also guzzles fuel and makes a lot of wasted heat. The power would be routed into a generator (unless its a fuel cell where that would be redundant) and run through an electric motor with a fully electronic transmission (no more gears to break). As for the waste heat from the process my cloak would conveniently absorb that heat and recycle it into the batteries thus giving me extra fuel economy.

This said, how do I estimate the power consumption of the various components of the thing? You seem to have a way of finding the numbers that I don't. What's your secret?

You're welcome. Glad that i can help
As for the rest of the components, i believe it is reasonable that computers and sensors taken together would consume at most 10-20 kW or 0.01-0.02 MW of electrical energy, as long as you stick with stabilized optical sensors, laser range measurement and thermal imaging. Radar however could be a different story, depends strongly on the used technology.
Now for the complicated part: the turret and the main gun. Both are big and heavy objects which you want to move fast. Let's start with the gun: Moving it sideways is already covered by the turret, so we only need to consider up-and-down movements of the barrel needed to stabilize the gun while the tank is moving. Because such movements are totally unpredictable, our only hope is to estimate an upper boundary for the required power to move the gun. Again, we have a dependency on the design of your tank but let's assume the gun can be aligned +- 30 degrees, so the longest movement sweep covers 60 degrees. The power needed for
such a sweep is calculated by:
P = M*w
where M is the torque applied to the gun and w is the angular velocity. Same formula applies for the turret btw, but setting a value for w is easier for the turret: The German Leopard 2 main battle tank can spin its turret 360 degrees in 9 seconds, so maybe it is reasonable to assume similar values for your case. Then,

w = 2*pi rad / 9s = (2*pi)/9 rad/s (angular velocity is expressed in rad)

Unfortunately i don't have such a nice number for the sweeping rate of the gun, so i just guesstimate here, that it can do the 60 degrees in 1 second. Then

w = (2*pi)/6 rad * 1/1s = pi/3 rad/s

as maximal angular velocity for the gun barrel.
Now, to M, the torque, and this is, where things start to get messy. Torque is calculated by multiplying angular acceleration with moment of inertia, which is notoriously hard to estimate and somehow an art in itself, as you can verify on Wikipedia. But since we are only estimating, i can provide you an example for the gun: Let's assume, we have a coilgun, so the barrel is somewhat shaped like a rod (A rod has a simple formula for its inertia, but is only an idealisation of the gun's true shape). If we rotate the rod around an axis that is somewhere near its middle and is perpendicular to it's length axis, then its inertia is
J = 1/12 * m * l^2
where m is the rod's mass and l its length. Again, picking numbers to finally arrive at a result, let's assume the gun has a length of 10 meters and weights about 3 tons (perhaps a little less than real tank guns, but close). Then, we get

J = 1/12 * 3000 kg * 100 m^2 = 25 000 kg*m^2

To calculate the torque, we need an angular acceleration (yea i know, another number we simply have to assume). But let's assume, our machinery is powerful and can accelerate at a quarter of its maximum angular velocity, so let

a = w/4 = pi/12 (which is 30 degrees, quite a lot for a change rate)

be the angular acceleration. The applied torque is then:
M = J*a = 25 000 kg*m^2 * = 6545 Nm

Mulitply by our angular velocity, we get:
P = M*w = 6546 * pi/3 = 6853 Nm * rad/s = 6853 W, or more loosely speaking, 6.8 kW.
That is the peak power which the gun stabilizing subsystem can draw alone.
Now, for the turret, you "just" need a moment of inertia and you can do similar calculations. The "simplest and dirtiest" trick that springs to my mind is: assume the turret is a brick and look up the formula for a brick's moment of inertia. A more refined approach would be: Fire up a 3D program and make a rough mesh of the turret's shape. Then save the vertices' coordinates and use them as mass points with
m_p = m / #vertices
for each point p (m is here the mass of the turret, think for example 35 - 40 tons).

Now for my secret: I used to be a Leopard 2 gunner during my mandatory service in the German military, so i have a decent intuition about tanks. My math-fu comes from me persuing a Master's degree in Robotics.
I hope the number-jungling above helps you in some way. If not, feel free to ask.

[Purple]

Now for my secret: I used to be a Leopard 2 gunner during my mandatory service in the German military, so i have a decent intuition about tanks. My math-fu comes from me persuing a Master's degree in Robotics.
I hope the number-jungling above helps you in some way. If not, feel free to ask.

Wow, you are cool.
And yes, I did need to put that first.

As for the rest of the components, i believe it is reasonable that computers and sensors taken together would consume at most 10-20 kW or 0.01-0.02 MW of electrical energy, as long as you stick with stabilized optical sensors, laser range measurement and thermal imaging. Radar however could be a different story, depends strongly on the used technology.

I was definitively going to use radar but it would not be turned on at the same time as the cloak. After all if the cloak absorbs energy emissions from the vehicle to the outside powering it together with an active sensor that works on the same wave length as the one I am cloaking against would not work. And yes, I do know that is sort of a weakness in the design that I would need to either keep the cloak up or the radar but that's a tradeoff I am willing to take. But as far as energy consumption over time goes I can imagine the radar would still be massively costly. This said, about the radar. I was thinking of having an unmanned remote controlled turret and have the hull of the turret be hemispherical and act as the radar antena. Or rather, the radar would be burried just under the turret armor like on the PAK-FA. Do you think this would work for a tank?

Also, when we are at the radar issue. Does a tank even need it? I imagine that you would be a good person to tell me that.

Now for the complicated part: the turret and the main gun. Both are big and heavy objects which you want to move fast. Let's start with the gun: Moving it sideways is already covered by the turret, so we only need to consider up-and-down movements of the barrel needed to stabilize the gun while the tank is moving. Because such movements are totally unpredictable, our only hope is to estimate an upper boundary for the required power to move the gun. Again, we have a dependency on the design of your tank but let's assume the gun can be aligned +- 30 degrees, so the longest movement sweep covers 60 degrees. The power needed for
such a sweep is calculated by:
P = M*w
where M is the torque applied to the gun and w is the angular velocity. Same formula applies for the turret btw, but setting a value for w is easier for the turret: The German Leopard 2 main battle tank can spin its turret 360 degrees in 9 seconds, so maybe it is reasonable to assume similar values for your case. Then,

w = 2*pi rad / 9s = (2*pi)/9 rad/s (angular velocity is expressed in rad)

Unfortunately i don't have such a nice number for the sweeping rate of the gun, so i just guesstimate here, that it can do the 60 degrees in 1 second. Then

w = (2*pi)/6 rad * 1/1s = pi/3 rad/s

as maximal angular velocity for the gun barrel.
Now, to M, the torque, and this is, where things start to get messy. Torque is calculated by multiplying angular acceleration with moment of inertia, which is notoriously hard to estimate and somehow an art in itself, as you can verify on Wikipedia. But since we are only estimating, i can provide you an example for the gun: Let's assume, we have a coilgun, so the barrel is somewhat shaped like a rod (A rod has a simple formula for its inertia, but is only an idealisation of the gun's true shape). If we rotate the rod around an axis that is somewhere near its middle and is perpendicular to it's length axis, then its inertia is
J = 1/12 * m * l^2
where m is the rod's mass and l its length. Again, picking numbers to finally arrive at a result, let's assume the gun has a length of 10 meters and weights about 3 tons (perhaps a little less than real tank guns, but close). Then, we get

J = 1/12 * 3000 kg * 100 m^2 = 25 000 kg*m^2

To calculate the torque, we need an angular acceleration (yea i know, another number we simply have to assume). But let's assume, our machinery is powerful and can accelerate at a quarter of its maximum angular velocity, so let

a = w/4 = pi/12 (which is 30 degrees, quite a lot for a change rate)

be the angular acceleration. The applied torque is then:
M = J*a = 25 000 kg*m^2 * = 6545 Nm

Mulitply by our angular velocity, we get:
P = M*w = 6546 * pi/3 = 6853 Nm * rad/s = 6853 W, or more loosely speaking, 6.8 kW.
That is the peak power which the gun stabilizing subsystem can draw alone.
Now, for the turret, you "just" need a moment of inertia and you can do similar calculations. The "simplest and dirtiest" trick that springs to my mind is: assume the turret is a brick and look up the formula for a brick's moment of inertia. A more refined approach would be: Fire up a 3D program and make a rough mesh of the turret's shape. Then save the vertices' coordinates and use them as mass points with
m_p = m / #vertices
for each point p (m is here the mass of the turret, think for example 35 - 40 tons).

Why not just assume a brick about the size of the turret of a modern day tank? Yes it will be more than it will end up in practice but a healthy safety margin is newer a bad thing.

[Number Theoretic]

Thank you, it's nice to be appreciated

Sorry for the absence. Had much to do for the university. Concerning the turret, it can be reasonable to assume the turret to be roughly a brick, like you suggested. Some Leopard 2 turrets are indeed very brick-ish. But since you mentioned that your turret is hemispherical it would make more sense to use the inertia moment formula for a solid hemisphere. I believe it is 2/5 *m*r^2 but i'm not entirely sure. If your figures are wildly unrealistic, better double check this

In modern-day tanks, the entire crew except for the driver and half the tank's ammunition is located in its turret. That's the reason why it is so big and heavy. If you want your turret to be unmanned, you can probably do that, but then it is most likely smaller (maybe 25 tons, 30 tons max. because then it is reasonable to store all the ammunition in the turret but it doesn't need life support for the crew). Your chassis needs to be bigger though to make room for the commander (and the gunner, if they are not the same).

Integrating the antenna in the entire turret hull can make it vulnerable to machine-gun fire, because the radar cannot penetrate armor, as far as i know. Radar covers are usually designed to be transparent for the radar's emissions but those materials are not designed as being bulletproof. But if you go for a relatively high radar frequency (i.e. millimetre-wavelength), you don't need a terribly large antenna. A good example is the radar sitting on top of the rotors of an Apache combat helicopter. Think that shape.

As for the use of a radar: It can indeed come in handy if the weather is shitty. Rain, Snow and especially fog are unfortunately a problem even for thermal imaging, contrary to popular belief. And i can tell you this firsthand Radar can see straight through fog or rain. Bonus points, if your imaging system has continuous zoom, a wide viewing angle and is a synthetic, fused image, composed from optical, thermal and radar data.

[Purple]

Concerning the turret, it can be reasonable to assume the turret to be roughly a brick, like you suggested. Some Leopard 2 turrets are indeed very brick-ish. But since you mentioned that your turret is hemispherical it would make more sense to use the inertia moment formula for a solid hemisphere. I believe it is 2/5 *m*r^2 but i'm not entirely sure. If your figures are wildly unrealistic, better double check this

I am mostly unsure about the actual shape as I am still doing reserch on that. As far as I know so far sloped armor does not really work against modern kinetic penetrators becouse the dart just diggs in anway. The only exception being realy, realy sharp slopes. And if I go for a roof mounted radar like you mentioned I can just put it on a pod on top of what ever shape I want. I figure that if I use a brick I can get a wildly larger number but one that will cover all things.

In modern-day tanks, the entire crew except for the driver and half the tank's ammunition is located in its turret. That's the reason why it is so big and heavy. If you want your turret to be unmanned, you can probably do that, but then it is most likely smaller (maybe 25 tons, 30 tons max. because then it is reasonable to store all the ammunition in the turret but it doesn't need life support for the crew). Your chassis needs to be bigger though to make room for the commander (and the gunner, if they are not the same).

That is true. I am looking at something that will put the crew in a similar sized position like tank drivers have in modern tanks. This said, how much space does a tank driver have inside? And how high do you think a hull I would need to acomodate all 3 crew members in such a pod?

Integrating the antenna in the entire turret hull can make it vulnerable to machine-gun fire, because the radar cannot penetrate armor, as far as i know. Radar covers are usually designed to be transparent for the radar's emissions but those materials are not designed as being bulletproof. But if you go for a relatively high radar frequency (i.e. millimetre-wavelength), you don't need a terribly large antenna. A good example is the radar sitting on top of the rotors of an Apache combat helicopter. Think that shape.

That I did not know. Thanks. Guess it's plan B than. Ill just mount a small pod on top of the turret like you said.

As for the use of a radar: It can indeed come in handy if the weather is shitty. Rain, Snow and especially fog are unfortunately a problem even for thermal imaging, contrary to popular belief. And i can tell you this firsthand Radar can see straight through fog or rain. Bonus points, if your imaging system has continuous zoom, a wide viewing angle and is a synthetic, fused image, composed from optical, thermal and radar data.

Man that is cool. You are a genius.
Implementing...

[Number Theoretic]

I am mostly unsure about the actual shape as I am still doing reserch on that. As far as I know so far sloped armor does not really work against modern kinetic penetrators becouse the dart just diggs in anway. The only exception being realy, realy sharp slopes. And if I go for a roof mounted radar like you mentioned I can just put it on a pod on top of what ever shape I want. I figure that if I use a brick I can get a wildly larger number but one that will cover all things.

Sloped armor doesn't work well enough to be a deciding factor, that's correct. However, what does work is a Whipple armor: leave some hollow spaces between two layers of armor material. The projectile then looses much of its kinetic energy while hitting the first layer and possibly gets fragmented. The spray of projectile fragments is then stopped by the second layer. I think, the ISS uses this kind of armor to protect against micrometeorites and i have seen this on the Leopards as well.

That is true. I am looking at something that will put the crew in a similar sized position like tank drivers have in modern tanks. This said, how much space does a tank driver have inside? And how high do you think a hull I would need to acomodate all 3 crew members in such a pod?

A tank driver usually has very little space. He is more lying on his back than sitting, because the driver's compartment is not very high</understatement>.
The problem is the turrent's socket. It extrudes deep into the chassis and has a wide base, otherwise your turret will slip off your chassis and that would look rather embarassing. You could extend the chassis' width, so either the gunner or the commander has some space next to the driver.
That still leaves one man who has to be placed. I see two options here: Either place the commander next to the driver and place the gunner in the turret (abandoning the unmanned turret concept). Or make the chassis longer and slighly higher to place the gunner behind the commander and the driver. If you can't exploit the unmanned-ness of the turret to shrink it, it will make your tank larger as it would be with a manned turret. However, i believe you can indeed shrink the turret's socket width, since it must only support machinery and no humans anymore. It still needs to be rather deep to ensure the turret sits tight, but it frees up some space for the gunner and you don't need to make the chassis much higher than the typical height of today's battle tanks.

As for the use of a radar: It can indeed come in handy if the weather is shitty. Rain, Snow and especially fog are unfortunately a problem even for thermal imaging, contrary to popular belief. And i can tell you this firsthand Radar can see straight through fog or rain. Bonus points, if your imaging system has continuous zoom, a wide viewing angle and is a synthetic, fused image, composed from optical, thermal and radar data.

Man that is cool. You are a genius.
Implementing...

You can even take this one step further by feeding the image data directly into the crew's contact lens displays or cybernetic eyes. And by tracking their head and eye movements to see where they are looking and aligning the sensor system's focus accordingly. Or go for a direct brain-machine datalink.

[Purple]

Sloped armor doesn't work well enough to be a deciding factor, that's correct. However, what does work is a Whipple armor: leave some hollow spaces between two layers of armor material. The projectile then looses much of its kinetic energy while hitting the first layer and possibly gets fragmented. The spray of projectile fragments is then stopped by the second layer. I think, the ISS uses this kind of armor to protect against micrometeorites and i have seen this on the Leopards as well.

Ah yes, good old spaced armor. Ill have that and ERA and an active protection system with both hard and soft kill capacity and possibly a separate laser dazzler on the commanders sight for flashing enemy infantry out in the open to blind them just for lol.

Also, I know hot tanks deploy smoke and I was thinking. How useful would it be if I could have some sort of very high power flash grenade I could fire up above the vehicle. The thing would fly to about half a meter above the tank and just flash like a normal flash grenade to blind enemy sensors and infantry temporarily, maybe also disrupting optical and IR missile guidance.

A tank driver usually has very little space. He is more lying on his back than sitting, because the driver's compartment is not very high</understatement>.

I heard its still not horribly uncomfortable or anything like that. Could a normal tank crew operate if they all were seated in such positions?

The problem is the turrent's socket. It extrudes deep into the chassis and has a wide base, otherwise your turret will slip off your chassis and that would look rather embarassing. You could extend the chassis' width, so either the gunner or the commander has some space next to the driver.

The concept of an unmanned turret is that the crew is seated inside the socket but are in the part fully submerged into the body. That way enemy projectiles that hit the turret won't hurt the crew. And even ammunition flashes should be harmless since the ammo is located in a separate compartment entirely. Its more likely to blow out the entire turret than go down into the body thanks to the separation. The way I figured it the hull would end up being taller but the turret would end up being smaller so it should equal out.

You can even take this one step further by feeding the image data directly into the crew's contact lens displays or cybernetic eyes. And by tracking their head and eye movements to see where they are looking and aligning the sensor system's focus accordingly. Or go for a direct brain-machine datalink.

I was thinking of giving each of the crew members a helmet like jet fighter pilots have that tracks the motions of their heads as you described and displayed what they would be seeing if the tank was not in the way.

[Number Theoretic]

Ah yes, good old spaced armor. Ill have that and ERA and an active protection system with both hard and soft kill capacity and possibly a separate laser dazzler on the commanders sight for flashing enemy infantry out in the open to blind them just for lol.

Or equip your laser with a variable power supply: Low power for range measurement and targeting, high power to dazzle or kill infantry.

Also, I know hot tanks deploy smoke and I was thinking. How useful would it be if I could have some sort of very high power flash grenade I could fire up above the vehicle. The thing would fly to about half a meter above the tank and just flash like a normal flash grenade to blind enemy sensors and infantry temporarily, maybe also disrupting optical and IR missile guidance.

The Leopards in our units had some special launcher buckets on their turrets which could launch smokescreens or even fragmentation grenades as a messy and deadly efficient way to get rid of infantry near your vehicle. Maybe such a multi-purpose system is interesting for your tank as well?
Launching flash grenades from it should be trivial but to effectively deter heat-seeking missiles you would need a decoy that
1) flies way higher than half a meter (think 10 meters) and
2) burns for at least 1 minute.
I reckon this should lure your missile away from the tank more effectively than a flash.

I heard its still not horribly uncomfortable or anything like that. Could a normal tank crew operate if they all were seated in such positions?

True, it isn't that uncomfortable and you reasonably can expect your crew to operate unter such conditions. I even slept once in the driver's seat, it's not that bad.

The concept of an unmanned turret is that the crew is seated inside the socket but are in the part fully submerged into the body. That way enemy projectiles that hit the turret won't hurt the crew. And even ammunition flashes should be harmless since the ammo is located in a separate compartment entirely. Its more likely to blow out the entire turret than go down into the body thanks to the separation. The way I figured it the hull would end up being taller but the turret would end up being smaller so it should equal out.

Ah, now i get it. That is a good idea indeed! It would make sense to place the gunner in the turret's socket then. If his seat is more hanging than sitting on a bottom plate you could leave out the bottom plate of the socket and place an emergency escape hatch for the gunner under the socket. Hanging seats also have the advantage to shield the crew from a shockwave coming from below when your tank hits a mine.

I was thinking of giving each of the crew members a helmet like jet fighter pilots have that tracks the motions of their heads as you described and displayed what they would be seeing if the tank was not in the way.

Fair enough. And it has the advantage, that your crew doesn't need to undergo some surgery.

[Purple]

Or equip your laser with a variable power supply: Low power for range measurement and targeting, high power to dazzle or kill infantry.

You are evil. You do know that. Me likes.

The Leopards in our units had some special launcher buckets on their turrets which could launch smokescreens or even fragmentation grenades as a messy and deadly efficient way to get rid of infantry near your vehicle. Maybe such a multi-purpose system is interesting for your tank as well?

Of course. Also, the smoke would be toxic to breathe in just for kicks. Since all my infantry will have powered armor with filters its not an issue for me but the other guy that does not anticipate it would find out the hard way not to smell the tank fumes.

Launching flash grenades from it should be trivial but to effectively deter heat-seeking missiles you would need a decoy that
1) flies way higher than half a meter (think 10 meters) and
2) burns for at least 1 minute.
I reckon this should lure your missile away from the tank more effectively than a flash.

I was thinking more along the lines of an extremely bright flash to burn out the optics and just plain overload the seeker heads much like what happens when you flash them with a laser. Once that is done, provided it works the missile becomes just a dumb shell that you can much more easily take down or kill with your active protection system. Also, with command guided missiles it has the bonus effect of taking out the operator.

True, it isn't that uncomfortable and you reasonably can expect your crew to operate unter such conditions. I even slept once in the driver's seat, it's not that bad.

Ah, now i get it. That is a good idea indeed! It would make sense to place the gunner in the turret's socket then. If his seat is more hanging than sitting on a bottom plate you could leave out the bottom plate of the socket and place an emergency escape hatch for the gunner under the socket. Hanging seats also have the advantage to shield the crew from a shockwave coming from below when your tank hits a mine.

That was the general idea. It turns the entire turret into a giant blow out hatch.
This said, I thought most modern tanks already had bottom escape hatches in case the thing flips over. Although I heard that some of the modern urban combat kits actually cover them up with armor plates to protect against IED's.

[Number Theoretic]

You are evil. You do know that.

I know

I was thinking more along the lines of an extremely bright flash to burn out the optics and just plain overload the seeker heads much like what happens when you flash them with a laser. Once that is done, provided it works the missile becomes just a dumb shell that you can much more easily take down or kill with your active protection system. Also, with command guided missiles it has the bonus effect of taking out the operator.

Could work, but sounds like extreme high radiation (the one that turns the woods around the tank into charred ashes). Even if your tank can resist it, launching it a couple of meters away seems like a good idea to me. And timing seems important since it's less effective when the missile is still several hunderd meters away and you need to shut your optics to protect them.

That was the general idea. It turns the entire turret into a giant blow out hatch.
This said, I thought most modern tanks already had bottom escape hatches in case the thing flips over. Although I heard that some of the modern urban combat kits actually cover them up with armor plates to protect against IED's.

Usually the driver does have a hatch. The rest of the crew is not that lucky if the tank flips over, unless the turret happens to be in a position where it is possible to crouch into the driver's compartment and then through his hatch. Don't know many details about urban combat upgrade kits though.

Of course. Also, the smoke would be toxic to breathe in just for kicks. Since all my infantry will have powered armor with filters its not an issue for me but the other guy that does not anticipate it would find out the hard way not to smell the tank fumes.

You, sir, are designing quite a deadly tank there. Keep me posted when it's done and leaving its enemys behind in agony! Oh, and send me a copy

[Purple]

Could work, but sounds like extreme high radiation (the one that turns the woods around the tank into charred ashes). Even if your tank can resist it, launching it a couple of meters away seems like a good idea to me. And timing seems important since it's less effective when the missile is still several hunderd meters away and you need to shut your optics to protect them.

Oh, in that case scratch it. As much as I like the idea of having a tactical nuke for point defense I have to draw a line somewhere.

Switching instead to an APS with several mini turrets each with a hard kill dart thrower and a laser dazzler to kill seeker heads and all slaved to a central computer being fed data from a radar. That should kill anything that comes close short of a dumb shell. And I have shields for that contingency.

This said, how much force do you think I would need to take out a normal shell. Not a sabot dart but say a HE or HEAT shell from a gun. Would I need to blow it up completely or just drill through it with a small dart or something?

Usually the driver does have a hatch. The rest of the crew is not that lucky if the tank flips over, unless the turret happens to be in a position where it is possible to crouch into the driver's compartment and then through his hatch. Don't know many details about urban combat upgrade kits though.

Man, that is messed up. But I guess they just figured anything that flips the tank over is going to mess it up sufficiently that it no longer matters anyway.

You, sir, are designing quite a deadly tank there. Keep me posted when it's done and leaving its enemys behind in agony! Oh, and send me a copy

Will do.

[Number Theoretic]

Oh, in that case scratch it. As much as I like the idea of having a tactical nuke for point defense I have to draw a line somewhere.

As awesome as it indeed is, i guess you're right. Decency and stuff

Switching instead to an APS with several mini turrets each with a hard kill dart thrower and a laser dazzler to kill seeker heads and all slaved to a central computer being fed data from a radar. That should kill anything that comes close short of a dumb shell. And I have shields for that contingency.

This said, how much force do you think I would need to take out a normal shell. Not a sabot dart but say a HE or HEAT shell from a gun. Would I need to blow it up completely or just drill through it with a small dart or something?

If you are using projectile-based APS like for example a Phalanx CIWS style gatling turret, i reckon that an ordinary gatling would suffice. Because what is killing the shell is mostly it's own kinetic energy. If it collides in mid air with a cloud of gatling bullets, the sum of its own kinetic energy and the ones from the gatling bullets would shatter it to pieces.
Lasers are a different story because there you can't exploit the shell's own kinetic energy. Following some stories about the US army's laser experiments, i somewhere picked up the figure, that beginning at 100 kW, lasers become useful on the battlefield. Which also includes the ability to heat up a shell sufficiently that its own explosives will kill it. A 1 MW laser is better but also demands more energy from your power source.

To deter missiles, a magnetron-based microwave emitter could be useful. If you have hundreds of kilowatts of power or even a few megawatts at your disposal, you could even dual-use this anti-electronics weapon to harass enemy infantry even more!

Usually the driver does have a hatch. The rest of the crew is not that lucky if the tank flips over, unless the turret happens to be in a position where it is possible to crouch into the driver's compartment and then through his hatch. Don't know many details about urban combat upgrade kits though.

Man, that is messed up. But I guess they just figured anything that flips the tank over is going to mess it up sufficiently that it no longer matters anyway.

Yup, that is messed up indeed. Like they say, war is hell. And yes, that "if your tank flips over you have worse problems than getting out of a flipped tank" rationale is the one they use. Or, if you screw it up in peace time, you can be turned back by a salvaging tank or a crane.

[Purple]

If you are using projectile-based APS like for example a Phalanx CIWS style gatling turret, i reckon that an ordinary gatling would suffice. Because what is killing the shell is mostly it's own kinetic energy. If it collides in mid air with a cloud of gatling bullets, the sum of its own kinetic energy and the ones from the gatling bullets would shatter it to pieces.

There is no way one can mount a gattling turret on a tank thou. At least not unless I redesign the whole tank to be a mount for it scraping all the rest. I mean these things are just massive, power intensive and generally more suited for a battleship. I was thinking of something more along the line of real world APS systems like the Arena or Drozd. Most likely a combination of all three.

http://fofanov.free.fr/Tanks/EQP/shtora.html
http://fofanov.free.fr/Tanks/EQP/arena.html
http://fofanov.free.fr/Tanks/EQP/drozd.html

Lasers are a different story because there you can't exploit the shell's own kinetic energy. Following some stories about the US army's laser experiments, i somewhere picked up the figure, that beginning at 100 kW, lasers become useful on the battlefield. Which also includes the ability to heat up a shell sufficiently that its own explosives will kill it. A 1 MW laser is better but also demands more energy from your power source.

I will probably stick to normal things than.

This said, I had the idea for a weapon back in the day that might be useful as a point defense system. After all it takes way less energy to fry a shell than a tank. But I have no idea if it would work. Ill lay it out here and you (and others) tell me what you think.

Say I fire a laser beam at an incoming shell. The laser it self is not the damage mechanism. Instead it only serves to ionize the air along the path to the shell sufficiently. Hooked up to the laser thou is a really strong capacitor. As soon as the laser does its job (practically instantly due to the speed of light and all) the capacitor discharges releasing what is in essence a bolt of lightning through that path. Now, this has a 50% chance of being awesome or just plain idiotic and make you facepalm. But physics is not my strong side so you tell me.

To deter missiles, a magnetron-based microwave emitter could be useful. If you have hundreds of kilowatts of power or even a few megawatts at your disposal, you could even dual-use this anti-electronics weapon to harass enemy infantry even more!

Man, where do you get these links?!
This is brilliant. I will have to read it to the end tomorrow morning since it's late but it sounds like quite a useful thing to have.

Yup, that is messed up indeed. Like they say, war is hell. And yes, that "if your tank flips over you have worse problems than getting out of a flipped tank" rationale is the one they use. Or, if you screw it up in peace time, you can be turned back by a salvaging tank or a crane.

Although that would be quite an embarrassment.