Raise Shields! Red Alert!

Boeing just got a patent for rudimentary sci-fi style shields. No, really, they did:

The patent describes a system that would detect the shockwave from a nearby explosion and create an area of ionized air – a plasma field – between the oncoming blast and the vehicle it was protecting.

The method works, says the patent, “by heating a selected region of the first fluid medium rapidly to create a second, transient medium that intercepts the shockwave and attenuates its energy density before it reaches a protected asset.”

By creating a temporary, superheated parcel of air with a laser, microwave or electrical arc, researchers believe that the shockwave would, in theory – it hasn’t been determined how far along Boeing’s research into this has got – dissipate once it hit the plasma field, leaving whatever was on the other side unaffected, or for the blast to at least be mitigated.

I see they’ve disguised that its for the new Boeing mechs by using a pic of an old Humvee.

Just don’t give the vehicle passengers red shirts, because shields or no shields…

Where are they getting the energy for this? I’m going to go out on a limb here and guess that a car battery won’t cut it.

Good question, Rich. To heat up a plasma fast enough to stop an explosive shockwave can’t be simple. Then again, if the Matrix taught us anything, it’s that humans make good power sources. Maybe that’s why there’s two guys in that Humvee.

My limited understanding is that you would need a lot of power generation or very dense power storage. So all generator or all dangerous capacitors? If generators that makes me think of a tanker of jet fuel, a jet engine and the shield device. And no room for anything else? I can’t see this working from stored power.

I imagine the method of heating is by using a laser or maser tuned to a frequency that is absorbed by nitrogen. Powerful continuous-beam lasers can burn long plasma tubes in the air, which is why they are extremely dangerous to use outdoors: the wind can blow the tube around, possibly right back at the laser or at some friendly target.

So possibly if you shoot a very powerful pulse laser focused a fixed distance away a whole bunch of times (scanning through a region like a CRT) you can create a plasma shield that might last a couple of seconds or as long as you can keep firing the laser.

But can you do that faster than the propagation of a high explosive that has already detonated? Detonated long enough ago to be detected?

The patent describes a system that would detect the shockwave from a nearby explosion and create an area of ionized air

So the speed of sound is the limit? Don’t see it.

The patent mentions detecting via light, radar, etc. Basically, you can detect at the speed of light while the shockwave itself is limited to presumably around the speed of sound.

Eh - modern active defence systems for tanks can engage inbound missiles before they hit.

(Iron Curtain (lol@the name), LEDS-150, Arena, Trophy etc.)

I don’t see see that as the hard part.

This isn’t targeted at missiles, but shockwaves. Say an IED explodes by a roadside. A system like this could protect a nearby vehicle and its occupants.

Then it has to sense the light from an explosion and not the shockwave. No?

Edit: Or the vehicle is constantly broadcasting radar. Which makes it the biggest target in the area.

Edit 2: That being so it becomes the perfect target for a solid projectile. Which I assume will not be stopped by a plasma shield.

Right, it wouldn’t be. You need some form of armor for that. The most dangerous projectiles would require Chobham or reactive armor.

So you are back to page one. Most IEDs are either right next to, or directly under a vehicle. I don’t see how this can be, in any way, cost effective. Or indeed effective at all.

What you would need is a power source that we don’t have now. And the ability to keep it running constantly. And a version of this that has a dangerous plasma envelope of unknown thickness. So we are in sci-fi territory now.

Edit: I love discussions like this.

Edit 2: So they have a vehicle sized fusion generator? Why haven’t they got a patent for that?

I think Mr. Fusion is prior art. And came out recently, per the documentary about it.

You could use a fluorine-hydrogen laser. Those were powerful enough even back in the 60s-70s to burn a plasma tube. The Army found out the hard way about the effects of wind on plasma tubes in the trials.

Needless to say no one in their right mind would ever put fluorine and hydrogen tanks on a battlefield where someone sneezing will destroy the vehicle or the base or wherever it is the tanks were placed. In the 60s the Army was apparently not in their right minds, however.

So yeah, I’m guessing it either needs super-duper-hyper-capacitors or an arc reactor or somesuch damn thing.

I don’t see how this would work. Let’s say an artillery shell lands near your Humvee. Or at least close enough that the shock wave is going to kill everyone. So in that 0.01 seconds or whatever that the shockwave takes to hit the Humvee, you’re going to generate super heated plasma? I mean… maybe the theory is valid - if you have a couple nuclear reactors and a massive laser/maser setup or something, but… yeah. I just don’t see how this would be feasible for anything less than the actual USS Enterprise from Star Trek or the like. I can’t even imagine most naval vessels being able to pull it off, much less something the size of a Humvee or even a tank.

Forget the Humvee, it’s just an illustration. Let’s say it’s a special defense vehicle that accompanies an artillery unit, or something like that. Perhaps the unit or its brigade is already equipped with anti-missile and even anti-shell systems, but this is a backup in case something gets through without scoring a direct hit.

Okay: that makes no sense either, but it’s better than pretending it can be mounted on a glorified jeep.

What the hell, it’s worth a bunch of government contract money to work through the concept, anyway, not to mention a directorship for someone and jobs for a bunch of engineers and product managers and liaising army officers and graft and contract sweeteners and all that stuff for the company.

As always Randal Munroe has something at least somwhat applicable

http://what-if.xkcd.com/13/
http://what-if.xkcd.com/109/
http://what-if.xkcd.com/119/

Doesn’t quite answer the question, but it does give somewhat the sense of scale of power needed. (especially that first link)

No, we must never forget the Humvee. How can I stick one of these on my Volt if the defensive system and power source combo is so large that it can’t be mounted on anything smaller than a tank or naval vessel? Nope, nope, nope. The Humvee is in the illustration and the Humvee will mount the prototype!