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Electromagnetic Pulse Gun To Help In Police Chases
adeelarshad82 writes "In an attempt to put an end to dangerous, high-speed police chases, scientists at Eureka Aerospace have developed an electromagnetic pulse gun called the High Power Electromagnetic System, or HPEMS. It develops a high-intensity directed pulse of electricity designed to disable a car's microprocessor system, shutting down all of its systems. Right now the prototype seen in a video fills an entire lab, but they have plans to shrink its size to hand-held proportions. Some form of this is already featured in OnStar-equipped vehicles though the electromagnetic signal used to disable the vehicle is beamed via satellite, and doesn't cripple the in-car computer, but rather puts it into a mode that allows police to easily catch and then stop the fleeing criminal."
Eureka Aerospace can call it "HPEMS", but really it is just another HERF device, and it is certainly not a new thing. In fact you can buy kits from places like this and build your own.
This is a High Energy Radio Frequency (HERF) gun not an EMP weapon, although the two are very similar in their final effects. EMP devices are omnidirectional and create a blanket pulse across a far larger portion of the EM spectrum. HERF affects a much smaller part of the spectrum, which allows the generating electronics to be tuned for higher efficiency and allowing the antennas to be directional. EMP devices are usually much higher power that fry the electronics, whereas HERF devices typically only cause disruption (requiring pulses to be sustained to prevent the normal function from restarting).
It will shut down the engine computers of most modern cars, but cars with carburetors and mechanical based ignition systems (ie. distributors) and diesel engines without electronic injection will be unnafected. While this may affect most cars and trucks made since 1970, it does not include them all.
To get to the power output that will stop a vehicle from distances usually seen in car chases would require a massive arrangement, capacitor bank, and a dedicated power supply to keep the HERF pulses sustained. This certainly will not be the kind of device that will be mounted on police cars any time soon.
I have to also wonder how effective it would be in an actual car chase (assuming they could find as way of making it mobile). They would typically be shooting it at the rear of the car where the bodywork would act as shielding for the engine computer, and there is nothing to stop portions of the RF pulses reflecting off the metal bodywork and disabling chasing police cars.