The Representation of Circular Arc by Using Rational Cubic Timmer Curve

摘要

In CAD/CAM systems, rational polynomials, in particular the Bezier or NURBS forms, are useful to approximate the circular arcs. In this paper, a new representation method by means of rational cubic Timmer (RCT) curves is proposed to effectively represent a circular arc. The turning angle of a rational cubic Bezier and rational cubic Ball circular arcs without negative weight is still not more than 4π/3 and n, respectively. The turning angle of proposed approach is more than Bezier and Ball circular arcs with easier calculation and determination of control points. The proposed method also provides the easier modification in the shape of circular arc showing in several numerical examples.