Degree Elevation of Interval B-Spline Curves

O. Ismail, Senior Member, IEEE Abstract— This paper presents an efficient method for degree elevation of interval B-spline curves. The four fixed Kharitonov's polynomials (four fixed B-spline curves) associated with the original interval B-spline curve are obtained. The method is based on the matrix identity. The B-spline basis functions are represented as linear combinations of the B-splines of a higher degree. The process of degree elevation is applied to the four fixed B-spline curves of degree to obtain the four fixed Bspline curves of degree without changing their shapes. Finally the new interval vertices *, -+ of the new interval polygon are obtained from vertices of the new fixed polygons of the four fixed B-spline curves. An illustrative example is included in order to demonstrate the effectiveness of the proposed method.