By John Rhea
RATON, N.M. - In the current concern over buried anti-personnel mines (an estimated 100 million throughout the world today, of which at least 4 million are in the Bosnian theater of operations), engineers at Raton Technology Research of Raton, N.M., are adapting resonant antenna sensor technology originally developed for the coal industry to a new prototype mine detector.
The purpose is to detect the non-metallic mines 2 inches in diameter or larger at depths to 31 inches. The devices weigh less than 20 pounds and look like the metal detectors that vacationers use to search for treasure on beaches.
The U.S. Army currently uses truck-mounted ground penetrating radars, which weigh about 60 pounds, to search for anti-tank mines, but they are only usable for metallic objects beyond two feet in depth.
Raton engineers are working under a $1.2 million, one-year cooperative research and development agreement awarded by the U.S. Defense Advanced Research Projects Agency in June.
A prototype is finished, and the next step is two weeks of testing at the Army`s proving ground at Fort A.P. Hill, Va., next May. The long-term goal is to drive the unit price down to $1,500 over a production run of 20,000 units, says Gerald Stolarczyk, senior systems engineer at Raton.
The basic technology is a resonant microstrip patch antenna, which measures the differences in the resonant frequency and impedance of the buried objects. Processing the data is a dual SC300 microprocessor from Advanced Micro Devices in Santa Clara, Calif., (equivalent to the Intel 386) and displayed to the operator via a Seiko G321E gray-scale unit.
The data are also stored on a PCMCIA memory card for retransmission via an onboard RF modem. This permits further analysis at a central location.
The device is based on Raton`s original horizon sensor mounted on the cutting head of coal mining equipment to allow measurements as far as 20 feet ahead so the miners can follow a coal seam. The goal was to improve mine safety while increasing coal production.
Also participating in the mine detector project is NASA`s Johnson Space Center in Houston, whose experts are providing their expertise in sensor arrays under a subcontract, Stolarczyk says.
Designers are using radar technology developed to help miners follow seams of coal to improve the U.S. Army`s ability to detect small non-metallic explosive mines.
