Technology Reduces Risks during Detection
Dees, Tim, Law & Order
Even though law enforcement officers have far more tools and technology today than those of previous generations, many of the risks they face are the same.
A motion sensor can advise that something is inside a building, but it can't tell you what it is, or even exactly where it is. A metal detector can alert you that someone has a magnetically sensitive object in or on his person, but it can't tell you if it's a gun or a belt buckle. In the end, someone has to check out the situation, placing them at risk of injury or death.
Developments in technology promise to reduce the risk by allowing a more precise threat assessment from afar. Some of the devices and methods invite challenges on 4th Amendment grounds that the founding fathers could scarcely have imagined.
Much of this technology has come from projects at national laboratories or government contractors, many of which were focused on weapons development in past years. Since the decline of the Cold War, many of the technologies under study at these laboratories have been re-evaluated to determine if they have public safety applications, and with considerable success.
Remote Laser Guidance System
Remotely operated vehicles (ROVs) are used for moving bombs and exploring hazardous materials spills. However, even the most skilled operator is handicapped by lack of stereo vision and depth perception through the single-camera video image used to control and guide the robot. Manipulating a control arm to pick up and deliver an object can be hit-or-miss because the operator can't visualize how close the gripper arm is to the object.
ETI Products has a laser guidance system that projects a three-dot pattern onto the object to be grasped. As the robot approaches the object, the dots begin to converge, and come together as one when the gripper "fingers" are around the object. If the operator overshoots and gets too close, the dots again diverge and display an inverted pattern. The device requires no modifications to the existing ROV, runs from common AA batteries, and is lightweight and self-contained.
Mobile Vehicle and Cargo Inspection System (VACIS)
Even the most diligent checkpoint inspector can search only a fraction of the vehicles that pass by his area of responsibility without backing up traffic for miles. Sealed containers can conceal any amount of contraband, and opening them invites potential damage to the contents and even more delay. The VACIS technology developed by Science Applications International Corporation (SAIC) is essentially a giant x-ray machine, capable of yielding a real-time Superman-view of the interior of a boxcar, truck trailer or other vehicle.
The system can be fixed or mounted on a truck for temporary use. The container to be examined is driven between a Cesium137 gamma radiation source and a series of three-foot high sodium iodide detectors. All are housed in fireproof containers. A Doppler radar automatically adjusts the image displayed on the operator's computer screen to compensate for the speed of the moving vehicle. The time required to scan a vehicle is a function of the vehicle's length, as the scan time is about seven feet per second. Thus, a 40-foot trailer could be scanned in about six seconds.
If the image shown on the operator's console is inconsistent with the vehicle's manifest, then the vehicle can be detained for a more thorough, manual inspection. The Cesium137 source emitter is capable of producing an image through as much as 2.5 inches of steel.
This inspection can be accomplished without any risk of radiation to the driver of the vehicle, as the beam is restricted to 14 inches in width. Residual emissions are limited to a few feet outside the scanned area, and are limited to less than 0.2 millirems per hour.
Even the area scanned directly is not exposed to a great deal of radiation. A typical inspection pass delivers a radiation dose of about five microrems, equivalent to a few hours of natural background radiation, or about 111000th the amount of radiation delivered during a dental x-ray. …