Applying the affine transformation intergated into autocad to determine exactly the lengths of axes pair of ellipses which are axonometric projection of the circles in or parallel to the coordinate planes

Abstract

– In the Descriptive geometry or Engineering drawing courses, in general an ellipse is intersection of a plane with a conical or cylindrical surface of the second order which is usually determined by a pair of conjugate diameters that is the parallel projection of the pair of circle’s perpendicular diameters. In order to easily construct the ellipse which is the axonometic projection of the circle, we must determine the axes pair of ellipse.
The paper applies the affine trasfomation intergated into AutoCAD to exactly determine the lengths of the axes pair of the ellipses which are axonometric projection of the circles of diameter d in or parallel to the coordinate planes. Compared with the results of other proved methods presented in the Engineering drawings, the research results of this paper are very exact..