Abstract
It is very difficult to analyze the behavior of a free arc column from a series of continuous images, e. g. the images obtained using a high-speed video camera. This paper presents a useful method for estimating the three dimensional path of the long gap free arc column using image processing technique without making any subjective judgments. In this method, first of all, a set of two orthogonal digital images of the arc column is entered as the first data. Next, this set of images is processed using a new extraction scheme in order to obtain automatically a linear shape as the extraction area, which is especially useful for arc images including indistinct or low contrast sections. Finally, a set of two linear shapes in the extraction images is transformed into the three dimensional path in the coordinate system at actual size. This paper also describes the results ofapplying this method to continuous images of the long gap free arcs obtained using high-speed video cameras. The change with time of the visualized path, the length and expansion for the arc column with the direct current of 100 and 2, 000A and the gap length of 1. 6m, were derived quantitatively.
