The objective of this research is to proposed a semi-automatic method for mapping electric poles using the structure from motion technique or SFM. First an epipolar geometry for each image pair is estimated. Then the 3D structures are obtained using incremental SFM technique which will give us both 3D point cloud of the study area and camera parameters. Also vertical 2D lines are extracted from the input images. These 2D lines and the 3D structures are then integreated for estimating the positions of electric pole in 3D space. Finally these 3D electric poles are then geo-registered by estimating 3D rigid transformation from embeded coordinates in the input images.

The experimental models of electric fields were set up by using 4 forms of electric poles a point - point point - rod parallel rod and coaxial ring. The equipotential lines and electric line of force were drawn by using Microsoft Office Visio Program 2007. The drawing of equipotential lines and electric field had shown the direction of electric field moving from the positive electrode toward the negative electrode and perpendicular to the equipotential line. The point - point poles in 10 cm. distance have constant and the highest electric fields which is 28.64 V/m. The electric fields of point - rod parallel rod and coaxial ring are 60.51 V/m 45.81 V/m and 181.98 V/m respectively.