A new method of rational approximation of the offset curves of planar Bézier Curves

The approximation of the norm of parametric speed is crucial to the approximation of offset curves.In this paper,a rational approximation method of the norm of parametric speed is given,which is more effective than the polynomial approximation.The approximation function of planar Bezier offset curves and the function for error estimation are provided.The algebraic rational approximation algorithm of offset curves,in which the direction of the normal can be kept,is derived.A numerical example is given to show the effectiveness of the new method.