Curve generation and modification based on radius of curvature smoothing

A method to generate a quintic B-spline curve which passes through the given points is described. In this case, there are four more equations than there are control point positions. Therefore, four gradients which are the first derivative of a quintic B-spline equation are assigned to the given points. In addition to this method, another method to generate a quintic B-spline curve which passes through the given points, and which has the first derivative at these given points is described. In this case, a linear system will be underdetermined, determined or overdetermined depending on the number of given points with gradients. A method to modify a quintic B-spline curve shape according to the specified radius of curvature distribution to realize an aesthetically pleasing freeform curve is described. The differences between the B-spline curve radius of curvature and the specified radius of curvature is minimized by introducing the least-squares method.

[1]  Caiming Zhang,et al.  A method for determining knots in parametric curve interpolation , 1998, Comput. Aided Geom. Des..

[2]  Panagiotis D. Kaklis,et al.  Fairing spatial B-spline curves , 1996 .

[3]  T. Kuragano,et al.  Curve Shape Modification and Fairness Evaluation , 2007, DAC 2007.

[4]  W. Boehm,et al.  The insertion algorithm , 1985 .

[5]  C. D. Boor,et al.  On Calculating B-splines , 1972 .

[6]  Janet F. Poliakoff An improved algorithm for automatic fairing of non-uniform parametric cubic splines , 1996, Comput. Aided Des..

[7]  Tetsuzo Kuragano,et al.  Curve Shape Modification and Fairness Evaluation for Computer Aided Aesthetic Design , 2008, 2008 International Conference on Computational Intelligence for Modelling Control & Automation.

[8]  D. Marsh Applied Geometry for Computer Graphics and CAD , 1999 .

[9]  Gerald E. Farin,et al.  Practical linear algebra - a geometry toolbox , 2004 .

[10]  Duncan Marsh,et al.  Applied Geometry for Computer Graphics , 1999 .

[11]  Gerald E. Farin,et al.  Curvature and the fairness of curves and surfaces , 1989, IEEE Computer Graphics and Applications.

[12]  W. Boehm Inserting New Knots into B-spline Curves , 1980 .

[13]  L. Piegl,et al.  The NURBS Book , 1995, Monographs in Visual Communications.

[14]  Gershon Elber,et al.  Geometric modeling with splines - an introduction , 2001 .

[15]  Wolfgang Böhm,et al.  Geometric concepts for geometric design , 1993 .

[16]  Gang Zhao,et al.  Target curvature driven fairing algorithm for planar cubic B-spline curves , 2004, Comput. Aided Geom. Des..

[17]  Wayne Tiller,et al.  Knot-removal algorithms for NURBS curves and surfaces , 1992, Comput. Aided Des..

[18]  Tetsuzo Kuragano,et al.  Interpolating curve with B-spline curvature function , 1998 .

[19]  Hiroshi Akima,et al.  A New Method of Interpolation and Smooth Curve Fitting Based on Local Procedures , 1970, JACM.

[20]  N. Papamichael,et al.  End Conditions for Interpolatory Quintic Splines , 1981 .

[21]  T. Kuragano,et al.  NURBS curve shape modification and fairness evaluation , 2008 .

[22]  Nickolas S. Sapidis Towards automatic shape improvement of curves and surfaces for computer graphics and CAD/CAM applications , 1992 .

[23]  Imre Juhász,et al.  Shape control of cubic B-spline and NURBS curves by knot modifications , 2001, Proceedings Fifth International Conference on Information Visualisation.

[24]  Josef Hoschek,et al.  Fundamentals of computer aided geometric design , 1996 .

[25]  Knut Mørken,et al.  Knot removal for parametric B-spline curves and surfaces , 1987, Comput. Aided Geom. Des..

[26]  Gerald E. Farin,et al.  Automatic fairing algorithm for B-spline curves , 1990, Comput. Aided Des..