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IMAGING OF A FAR SURFACE OBJECT WITH HORIZONTAL LOOP ELECTROMAGNETIC INSTRUMENT

Joseph A. Owolabi

Abstract


An electromagnetic imaging instrument with variable voltage and frequency was designed and constructed to image a far surface metallic object. The methodology involved the transmitted voltage of 250V to the transmitter core with frequency of 300Hz. The liquid crystal display (LCD) module was used to display the computed voltage values after being processed by the microcontroller unit. The constructed instrument took measurement at horizontal profiling to 30m along the surface and vertical profiling to 310cm across the surface. The horizontal profiling and vertical measurements were made on 0cm,70cm,120cm,150cm,180cm,210cm,240cm, 310cm across the surface and 0m, 4m, 7m, 12m, 17m, 20m, 25m, 30m, along the surface, where cast iron metal pipes are placed on the flat surface. The 130cm iron pipe placed between 90cm – 220cm while the 72cm iron pipe was placed between 119cm -191cm perpendicular to the surface. The results obtained show that as the distance along and across the surface increases, the receiver voltage decreases when 250V are transmitted. Various 2 –D column plots were made from measured receiver voltages for flat surface measurement. These 2-D column plots of the data indicate the locations of the test iron pipes and other metallic objects on the flat surface measurements. Keywords: Imaging, surface, object, horizontal loop ,electromagnetic instrument.

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References


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