A.R.C. Tech: the SWIPE Prototype (Patreon)

I mentioned it a few times in my ARC story as a clawlike pistol but never really went int further detail.

Well now, here it is!  The Slow Wave Pulse Inducer device for non-invasive, electromagnetically induced anesthesia (SWPI) casually called Swipe.

Basically, its close range pistol that you place over someones head and pull the trigger, knocking the target unconscious.  Since it has no range beyond the area inside the claw, it has no use as a weapon or in combat.  A.R.C. agents must either distract or sneak up on their targets to use.

How it works:

The general idea is that you place two electromagnets, one on either side of the head, then turn them on in such a way that a magnetic field is generated across the brain, from left to right or right to left, then quickly reverse it, causing a current to flow from one side of the brain to the other.  

My thinking is that by inducing a directional current across the brain will force the neurons to "sync up" and generate a slow wave across the brain.

When the brain is active and awake, neurons are firing off all over the place in a seemingly chaotic manner, never in any kind of pattern or order until given an anesthetic.  When anesthetized, the neurons in your brain "line up" and a slow wave is generated in the  30–100 Hz range.

In researching this topic, it is unclear as to weather there is any directionality to these waves, meaning the actual placement of the magnets might be wrong.  The waves that the literature refers to are waves seen on an EEG, meaning that a wave doesn't sweep across the brain, it means that it is increases and decreases in activity over time.  That kind of wave.  The direction of this induced current might not even matter.

Many articles I have found have shown that magnetic fields can and do cause neurons to activate and nerve function to change, but it looks like the amount of current needed to stimulate nerves is small and the magnetic field to create that current is conversely fairly weak, but only at very close ranges (mm apart.)  Since the falloff distance for magnetic fields follows the inverse square law, the magnets (even pressed right against the head) would have to be incredibly strong, hence, the superconducting magnets.

But this then presents another problem: field strength gradient.  The field would be incredibly strong at the side of the head and far too weak in the center, meaning that half your brain would get too much and the other half won't get enough, with only a small area in the middle getting the right amount.

I didn't find anything about what happens when too much current is induced in living nerves, but I think its safe to say its not good. Enough current could literally fry nerves, and that isn't the purpose of this device.

Also, I do know that creating a magnetic field from left to right wont cause an electric field in the same direction.  The field, and thus, current induced will be at a right angle to the axis of the magnets.  But having the magnets arranged above and below the head would mean you'd have to be facing your target to use the device, and that just wont do!

So I guess i'm going to have to add another miracle exemption here: the current induced by a magnetic field in this way is sufficient to cause the brain to enter slow wave anesthesia (SWA), and that it doesn't also fry your nerves.

If you can get past all of that, then you have the Swipe!  A pistol grip tool that has 3 arms and a helium tank at the front.  

Construction:

the "reciever" or "frame" is made from 2 hollow pieces of injection-molded hard plastic fused together down the middle.  The grip is has a core of hard plastic with a softer plastic covering it.  The trigger, trigger axle and axle mount are all made of metal, as are all linkages.

The arms are spring loaded and must be folded back manually.  There is no mechanical linkage between the arms, so they each have to be folded back individually.

Position 1 and 2 shown above. Position 1: Arms are retracted.  Position 2: Arms are extended.  Position 3 (not shown): the magnet arms extend further, making the magnets contact the head and apply pressure (additional "grip"). Position 3 refers to the maximum of this extension.

Battery is located in the bottom of the grip.  This is to offset how front-heavy the device gets when in position 2.

Capacitors located above the side arms along either side of the top part of the frame that catches the top arm when folded back to position 1.

(see diagram for more details)

Operation:

Once a target is located, operator pulls trigger to the first stop.  This releases all the arms to swing into pos 2 and causes capacitors to charge.  Once target is sufficiently distracted and capacitors fully charged, operator sneaks behind target and places device over target's head (grabs their head with the claw) then squeezes trigger.  This causes the claws to squeeze toward pos 3 and is powered by direct 1:1 cable linkage to the trigger.  Operator must have a strong grip.

Once the trigger reaches the halfway point between pos 1 and pos 2, helium is sent through the tubes to the magnets where it cools them to superconducting temperatures.

Then, after a carefully timed delay to allow time for the magnets to cool down, capacitors dump all their current into the electromagnets, causing a brief spike in magnetic field between the claws followed by an immediate collapse, inducing a brief but powerful current in the brain of the target, inducing SWA in target

 Operator must then replace the helium tank, as it contains only enough coolant for one use.  Any more would make the device too heavy to be practical.  The tank has to be extra heavy in order to contain the pressure that helium will put on it, and due to the nature of helium (it will leak through even the best valve), each tank must be filled prior to mission execution and emptied upon completion.

Additional note:

If there were a way to create coils with Yttrium Barium Copper Oxide (YBCO) that could bend around a core, then the use of helium would be unnecessary and the device could instead use liquid nitrogen as its coolant, since YBCO becomes superconducting at 93 K and liquid nitrogen's boiling point is 77 K.  I wan't able to find any info about its mechanical properties and, having never worked with it, I assume it is a ceramic and quite brittle.

Liquid nitrogen is a LOT cheaper and easier to make, store and dispense than helium, so it would be greatly preferred.