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The Military Transportation

The Pentagon's Ray Gun Can Stall Cars (defenseone.com) 182

john of sparta quotes Defense One: The Defense Department's Joint Non-Lethal Weapons Program, or JNLWD, is pushing ahead with a new direct energy weapon that uses high-powered microwaves to stop cars in their tracks without damaging the vehicle, its driver, or anyone else. The jammer works by targeting the car's engine control unit causing it to reboot over and over, stalling the engine. Like an invisible hand, the microwaves hold the car in place. "Anything that has electronics on it, these high-powered microwaves will affect," David Law, who leads JNLWD's technology division, said in March. "As long as the [radio] is on, it holds the vehicle stopped."
It weighs 400 pounds -- it's the size of a large copy machine -- and uses 300 kilowatts of power that's generated by a gasoline-powered turbine.

"To deploy it, the driver would pull out in front of the attacker and turn it on."
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The Pentagon's Ray Gun Can Stall Cars

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  • by taylormc ( 926607 ) on Sunday April 29, 2018 @03:43AM (#56522397)
    ...with 300 KW of microwave energy? Good luck with starting a family after that.
    • by thesupraman ( 179040 ) on Sunday April 29, 2018 @04:03AM (#56522445)

      Ah, but its nice warm fuzzy AMERICAN microwave energy, not evil terrorist radiation.
      Its like the American laser 'defense' weapons that instead of burning out eyes, just gently exfoliate the facial skin in a loving caress.
      Because, you know, otherwise they would be illegal blinding weapons, against conventions the US signed.

      • a) Aren't cars made of metal shielding? Don't ECU's have shielding of their own?

        b) Don't they have people inside them? What happens when 300kW of microwave power hits the meat?

        • by Aighearach ( 97333 ) on Sunday April 29, 2018 @01:57PM (#56524269) Homepage

          That shielding won't save you, and is actually the point! The shielding absorbs the energy, causing a large transient voltage spike in your car's electrical system. That causes the ECU to crash, because it isn't designed for those conditions.

          One of the key things to understand here is that the car only has two electrical connections, battery + and battery -. Battery - is often called "ground," it will tend to be at local ground because it is referenced to the vehicle chassis which will likely be at ground potential when you start the car. But it doesn't have a third wire with an actual Earth connection, and the wheels are usually electrical insulators. What that boils down to is that shielding works by converting the RF interference into a short voltage spike, some of which is converted to heat in the ECU and any other electronics with voltage regulation. All the devices in the car are already expected to survive "double battery condition," which is when the tow truck driver gives you a jump start using 24V, which is really 28V+ because their engine is running and their battery is charging voltage. So there is a huge amount of voltage margin and the shielding works well without even having system-wide voltage regulation. But in the extreme case, as with this device, you eventually overload the ECU's voltage regulation, and since the circuit is designed to be robust, it simply crashes and reboots as soon as the spike dissipates. Repeated use could easily damage a vehicle, though.

          For protection against this, I'd want to try something low-tech like a wire brush connected to the chassis that can drag on the ground slightly, so that voltage spikes can find a path to Earth instead of getting stuck in the circuit.

          • Standard automotive tests require components to survive 60V peaks.
            According to Texas Instruments, an automotive load dump for a 12V system can peak at 87V, a 24V system at 174V

            It's not the power wires you need to worry about. They're well filtered, protected and low impedance.
            It's the signal wires that would do the most harm. They don't have much more than ESD protection, usually diodes to each power rail. Inducing a large enough current and voltage in, for example the oxygen sensor wire, usually located on

            • Standard automotive tests require components to survive 60V peaks.
              According to Texas Instruments, an automotive load dump for a 12V system can peak at 87V, a 24V system at 174V

              That's a nice idea, but there are warnings in my 1998 A8's manual about overvoltage during charging. Apparently it only takes something like 19V to damage the PCM. Newer vehicles are probably not actually any better.

              • Perhaps they have load dump protection elsewhere in the system.
                Perhaps the load dump protection in the PCM works by shunting current until a fuse blows, as it only needs to survive less than half a second at those high voltages.
                Perhaps they don't care, and if your battery connections fail while the engine is running, you're fucked.

            • Those load dump tests are a blast!
              Reverse battery, double battery, reverse double battery, caps and diodes failing everywhere!

              Modern electronics are pretty good at dealing with electrical interference. We used to test with a 25kW Marine radar to be sure it wouldn't cause problems with our systems. Once everything went to surface mount components, and 4+ layer PCBs, the robustness, and noise immunity of electrical components increased significantly.

          • by rfengr ( 910026 )
            Earthing something has absolutely nothing to do with electromagnetic shielding.
            • Right. Good work. It has nothing to do with the shielding.

              It has to do with giving the voltage spike that results from successful shielding somewhere to go.

              Like in a device plugged into the wall with a three-prong plug: If you dump the noise back onto neutral, it pushes noise into everything else plugged into the same supply circuit. If you dump the noise to Earth, then that doesn't happen.

              So for example, take an old, simple electric kitchen blender with a metal body, and a two prong plug with no Earth conn

    • Yeah, this is why you short the field with something conductive with holes less than half the wavelength -- so, less than 12cm in this case. Or, were you confused as to why your microwave had a window with a bunch of little holes? ;) Also this tech is fucking old -- people have been stalling cars since the 1980s doing this using a conical lens on a magnatron (the magic box inside a microwave that does the microwaving). Most cars electronics are shielded though, so much of this is kind of worthless, now.
      • Most cars electronics are shielded though, so much of this is kind of worthless, now.

        They still need plenty of wires to penetrate the shielding. Of course, all the wires are EMI filtered, but only for normal levels of interference, not 300 kW aimed directly at the vehicle.

        • by torkus ( 1133985 )

          'Focusing' is the key here...and also the danger. Is it 300kw/m^2 focused and tracked on the target ... or 300kw/100m^2 flooding an area?

          For easy numbers, assume a 75kg person and fudge to 4J*g/deg C then 300KJ or 300Kw will raise your body temp by 1C every second. You are unlikely to concentrate the full power directly on an individual but this is also meant to hold a car in place so your duration is potentially minutes or more.

          Very curious to know the power density impacting the target vehicle. If it's

    • by hey! ( 33014 )

      300 K is power.... the *rate* of energy being expended. So if you use that power for a very short time, it's actually not much energy.

      People are, to a first approximation, a 20 kilo bag containing 40 liter of water. It takes roughly 168000 joules to raise the temperature of that water by 1 degree. So 168 kJ/300 kw == .56 seconds. So a 10 ms pulse, if delivered entirely into an average human body, would only raise the temperature of that body by one hundreths of a degree *averaged over the entire body

      • If you're pulsing, you can charge and release the charge on a capacitor. You only need a 300kw generator if you're (a) continuously sending or (b) pulsing at significantly greater energies.

        • by hey! ( 33014 )

          Or if you want to be able to power the thing up quickly, say to take a second shot.

      • "Surface" in this case would be something like the top 12cm, though, right?

      • a 20 kilo bag containing 40 liter of water.
        1kg of water is 1 liter, so you are somewhere somewhat off ...

        • by torkus ( 1133985 )

          Children can be ter'rists too ya know...

          But i've no clue about 40kg of shit in a 20kg bag thing

      • by torkus ( 1133985 )

        Actually 300kw is the power supplied by the generator according to tfa. Their pulse power may be orders of magnitude higher depending on the duty cycle but your generator is going to be your average power. That leads me to conclude this isn't a one-shot-disabled but instead active, continuous interference with the vehicle computer.

        Even 10% of the (assumed) average power impacting a person is enough to raise body temp to lethal levels in a minute or so. 75kg @ 4J*g/C = 300kw*s/C so 10% of that for 60 seco

    • No. Also, this was demonstrated on American television 12 years ago; the demo had a driver in the car, and the journalist standing right next to it, because there is no reasonable health danger from short-term exposure.

      The thing about "starting a family" tells me you watch a lot fictional television "shows," and that you don't understand what the content is.

  • How about that Faraday's Cage tho? :)
    • That's when they pull out your gun and shoot your tires. Which they should have done in the first place anyway. Especially since they have big vehicle in front of you anyway (or at your side, or whatever).
      • by Calydor ( 739835 )

        Yes, because bullets ricochetting into traffic along with a sudden flat tire or two, on a car controlled by a driver now in a state of panic - that's so much better than a car that just stalls and drifts to a halt.

      • That's when they pull out your gun and shoot your tires. Which they should have done in the first place anyway. Especially since they have big vehicle in front of you anyway (or at your side, or whatever).

        Depends, are we talking civilian/LEO use or military use. For the later, yeah, blow that shit to bits. For law enforcement, no, you do not shoot at a car regardless of whatever stupid shit we see on TV, not unless you have serious circumstances to save life and limb (yours or someone else.) Once the bullet leaves the barrel you have no control where it goes, but you almost certainly have the responsibility of what/who it hits accidentally or not.

        That's why there are things like spike strips and caltrops (

      • If they pull out my gun and shoot my tires, I already stopped caring about my car when whatever happened immediately before that happened that caused me to be outside my car, and them to be holding my gun. :)

        A more likely use case would probably be when a car is approaching a checkpoint and doesn't slow down or stop at the correct spot. The correct military decision is to destroy the threat, but it is more often a civilian idiot or phone zombie than some sort of attacker, and it is unpopular to shoot people

    • A car is not a Faraday cage. There are plenty of holes and gaps between panels.

  • UFO's (Score:1, Offtopic)

    "As long as the [radio] is on, it holds the vehicle stopped." Creepy
  • 1.) gasoline engine - carburator - passive tech works not very efficient but works, with manual choke

    weakness1: ignition coil, could get damaged
    weakness2: transistor based ignition - solution -> back to non-transistor based iginition

    but much less electronics.

    2.) diesel engine - inline fuel injection pump with passive spring "controlled" injectors
    no electrics at all

    Start it and it runs till its out of fuel.

    3.) yes K.I.T.T. had it long before this article.

    • by tlhIngan ( 30335 ) <slashdot@w o r f . n et> on Sunday April 29, 2018 @04:53AM (#56522543)

      passive tech works not very efficient but works, with manual choke

      For varying degrees of "works".

      It's not just efficiency, it's basically ease of operation. One of the big things about modern cars is they are "twist and go". You twist the key (or push the button nowadays) and the car goes. Doesn't matter if the engine is hot (vapor lock is not an issue), very cold, or any other thing, including poor fuel. You want it to go, it goes, and unless something is very wrong, it will go. (You can even shoot out cylinders and while it stalls the engine, you can have a V8 engine with 6 dead cylinders still barely run. It's not happy, but the computer is able to compensate and get you home, albiet slowly).

      Anyhow, did you wonder why it took 300kW to do it? It's because an ECU is very well shielded to begin with - the metal body of the car already is a great faraday cage. But the ECU is also encased in a metal body because it's a very challenging environment with a lot of stray RF caused by all the high voltages around.

      In fact, if you're willing to settle for post-millennium vehicles, disrupting the keyfob-car communications will generally be far easier - the windows in the passenger compartment don't generally block RF, and the signal levels are weak since keyfobs are powered by itty coin cell batteries with poor peak power performance, so they don't have much transmit power. (I had to replace the battery in my keyfob - it still measured 3V, while batteries that are generally dead used in PCs measure pretty damn close to 0.5V. Heck, even my watch which died suddenly had a battery that measured around 0.5V. No doubt the battery was low, so it couldn't supply the necessary power for the transmitter)

      • by burni2 ( 1643061 )

        For the twist and go I will install a carburator with auto-choke (passiv) and will put on a sticker into the window

        1.) Turn engine for 1,5s - then stop (to have fuel in the fuel hose - passive on engine fuel pump - tends to have a backflow to the tank)
        2.) Push gas pedal 3 Times (to trigger the accelerator pump to have enough fuel in intake)
        3.) start engine ... yeah I would not sell any cars.

        Btw. you might like this documentary especially Part2

        Part1: https://www.youtube.com/watch?... [youtube.com]
        Part2: https://www.youtub [youtube.com]

  • by Gravis Zero ( 934156 ) on Sunday April 29, 2018 @04:06AM (#56522449)

    Another technical achievement that can be defeated by aluminum foil. ;)

    • by MrKaos ( 858439 )

      Another technical achievement that can be defeated by aluminum foil. ;)

      So you're advocating walking around wearing a tin foil hat?

      Stylish!

    • Another technical achievement that can be defeated by aluminum foil. ;)

      True, that. Just make sure to wrap it well enough to get under the car's wheels, because the car is already shielded and the only workable theory of operation is to create a path to Earth to dump the transient.

  • by Harold Halloway ( 1047486 ) on Sunday April 29, 2018 @04:26AM (#56522473)

    My Austin Allegro is impervious to anything.

    • My dad had a Maestro and there's no way some gadget like this would have stopped it, mainly because it wouldn't start in the first place.

  • by mridoni ( 228377 ) on Sunday April 29, 2018 @04:30AM (#56522491)

    If you have to take along a 300kW gasoline-powered turbine and a copy machine-sized unit, isn't it easier to just throw this stuff in the path of the car you want to stop?

    • Re:One question (Score:5, Insightful)

      by wierd_w ( 1375923 ) on Sunday April 29, 2018 @04:58AM (#56522565)

      Really, I had this idea a very long time ago. You don't need the full 300kw power system if you use a pulsed maser instead of a constant broadcast. That means you can use some kind of storage system with a smaller input, such as an air-coil resonant tank, or a super-capacitor array. You just need to be able to deliver the 300kw on each pulse. It takes time for the ICM to reboot; you dont have to keep roasting its ground lanes with signal. You just have to make it malfunction and restart in a reasonable interval. 1hz pulse width would be sufficient.

      Assuming these tools are driving their emitter nonstop, that would let you use 1/60th of the power generation hardware, or ~5kw power system. Even less if you use a 2sec interval instead of 1.

      For some variations of the pulse timing, a second alternator on the delivery vehicle would be sufficient; the bulky part would be the super capacitor array, which could be installed in the trunk, or in the rear seats.

      The referenced idea I had called for a klystron resonant cavity with a pulsed electron beam, and a low power reference microwave signal produced by a small magnetron. As long as pulse duration time is some whole integer product of the reference signal frequency, it should work fine.

      Hilarious that an idea I had as a teenager in the 90s is being seriously considered here though. LOL.

      • I actually considered this too when I took some Navy electronics training. My biggest concern was the heat dissipation. For the exciter in the EA6B, we had a dedicated oil cooling system and it was HEAVY. Of course, more energy was being poured into that, a full jet engine's worth, than 350kw, but still, heat is an issue.

      • It takes time for the ICM to reboot; you dont have to keep roasting its ground lanes with signal. You just have to make it malfunction and restart in a reasonable interval. 1hz pulse width would be sufficient.

        I've seen operating engine ECMs reboot due to coding bugs. They boot incredibly fast. In milliseconds. The engine would keep running, but it would misfire when the ECU rebooted. The engine and vehicle have kinetic energy, so they don't stop dead in their tracks.

        I'm not saying it won't work, but 1hz may not be fast enough. It might only slow the engine down.

    • If you have to take along a 300kW gasoline-powered turbine and a copy machine-sized unit, isn't it easier to just throw this stuff in the path of the car you want to stop?

      I suggest that would mean there wouldn't be an excuse to deploy microwave weapons within civilian populations.

      • If you have to take along a 300kW gasoline-powered turbine and a copy machine-sized unit, isn't it easier to just throw this stuff in the path of the car you want to stop?

        I suggest that would mean there wouldn't be an excuse to deploy microwave weapons within civilian populations.

        Almost everywhere the military operates already has a civilian population. Wars aren't conducted safely off-planet, or whatever. If you're well-enough educated you can tell which civilians it will be used on based on which part of the government is operating it. ;)

        • by MrKaos ( 858439 )

          If you have to take along a 300kW gasoline-powered turbine and a copy machine-sized unit, isn't it easier to just throw this stuff in the path of the car you want to stop?

          I suggest that would mean there wouldn't be an excuse to deploy microwave weapons within civilian populations.

          Almost everywhere the military operates already has a civilian population.

          Usually not their own.

          Wars aren't conducted safely off-planet, or whatever.

          I've never thought of wars that ensure peoples safety.

          If you're well-enough educated you can tell which civilians it will be used on based on which part of the government is operating it. ;)

          We have seen that. We've seen microwave weapons used on citizens in England protesting American bases.

    • by Anonymous Coward

      I think it's primary purpose is as a non-lethal way of stopping 3rd world suicide bombers from driving their IED-cars into US military convoys.

      (The other option is that they just assume the worst and fire .50-cal Gatling guns at any suspected vehicle. "This kills the crab.")

    • One word: Prototype.

    • That's what I was thinking, too, when I read this quote:

      "To deploy it, the driver would pull out in front of the attacker and turn it on."

      At that point, you could just drop the equipment in the path of the "attacker". Or just step on the brakes.

      Also, isn't "fugitive" more accurate here?
    • If you have to take along a 300kW gasoline-powered turbine and a copy machine-sized unit, isn't it easier to just throw this stuff in the path of the car you want to stop?

      No, you park it right next to the road to stop cars at the checkpoint, if you put the equipment out in the road without turning it on they'll just hit it with a suicide bomber.

      This is to stop the car a few feet farther back, keeping most of the checkpoint outside of the blast radius, and allowing a way to kill less civilians who don't stop at the right time.

  • I'll wait a year and get the hand held model on Banggood for $10
  • Law suits from the first person operating a target vehicle in that trial to get cancer can't be that far off.
    • by schwit1 ( 797399 )

      Good luck proving it was this microwave generator and not the thousands of other possible causes.

  • by carlhaagen ( 1021273 ) on Sunday April 29, 2018 @07:27AM (#56522827)
    If you'd be left with only your fertility taken from you after that you'd be lucky. It's fucking insanity and downright lies to label this power of EM aimed at a person as harmless.
  • If the tiny EMAG energy of a cellphone is supposed to cause brain cancer, how can 300kW blasted at you NOT do something deleterious??
  • and it was strong enough to mess with a car's magneto. Normally I would take this sort of thing with a grain of salt, but my great grandma saw it in action.
  • by ledow ( 319597 )

    Gimme 300KW of directed energy from a gasoline-powered turbine, and I'd stop a car no problem at all.

    But this is just stupid.

    "To deploy it, the driver would pull out in front of the attacker and turn it on."

    Sigh. Press button. Stinger drops in road. Problem solved without lots of stupid and dangerous ideas.

    And anything the military might want to attack that's not just a commercial car? Yeah, they'll shield the relevant parts against this from the first time you use it.

    Sometimes I really wonder just how

  • For sale: 1982 Mercedes-Benz 300SD. The fuel cutoff is vacuum-driven, and there are zero computers involved with the normal operation of the vehicle. It can even be pull-started (or bump started given a sufficiently large hill) in spite of the automatic transmission. The transmission is governed by a vacuum line and a cable so it doesn't need a computer either. Runs like a champ, but needs extensive cosmetic work like new paint and a good carpet cleaning. Located in Kelseyville, CA. $2500 OBO

  • The internal combustion engine killing ray was a staple of 1920s and 30's pulp fiction super-science villains. It was a common trope in spy thrillers and detective stories. In those stories airplanes (the highest of high tech) were continually falling mysteriously out of the sky, brought down by the villain and his henchmen's engine freezing ray.

    If you think about it, the internal combustion engine in 1930 was newer to the general public than the computer is today. Before the model T in 1908 it was an ex

  • of the attacker and turn it on."

    And if it doesn't work, you've stopped that truck full of explosives and it only cost one soldier and a truck full of worthless electronics...

  • It weighs 400 pounds -- it's the size of a large copy machine -- and uses 300 kilowatts of power that's generated by a gasoline-powered turbine. "To deploy it, the driver would pull out in front of the attacker and turn it on."

    Wouldn't putting a giant truck carrying the 400 lb "ray gun" and generator in front of the oncoming car also stop it?

  • And you can knock down drones at distance too.

  • Much better solution.

"Mach was the greatest intellectual fraud in the last ten years." "What about X?" "I said `intellectual'." ;login, 9/1990

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