Forced emergency stop devices

 U.S. police have put to the test 2 control device driver, forced to make an emergency stop in any case, even when the driver tried to ... crash barrier broken.

                                                     Pit-bul and Nighthawk are such devices.

Pit-bul is a series of sharp nails, diameter 17mm, length about 18cm is controlled by electrical relays. When signaled to stop the car, if the driver still tries to jump through checkpoints, police will switch remote, sharp nails mounted on the roads will pop up so that the tires deflated quickly and the vehicle must be stopped back.

Meanwhile, the Nighthawk is a network drive, each fiber synthetic fiber diameter of about 8mm. Two hard grid is compressed in the box compressed air, high pressure, "buried" in the reducer rubber band. If the driver tried to jump through, despite police car stop, the wheels of the suspects accidentally activated, causing the hard mesh pop blast of compressed air, thrown vertically either side of the wheel. Only a few meters from the road, the only time in milliseconds, the grid will expand his wheel, hard bunch of suspects, forcing the car to stop.

Two devices on the Department of Homeland Security in conjunction with the Academy of Sciences made​​.