Study on B-Spline Surface Fitting onto Dense Measured Point Data: Method of Setting Knot Location and Parameter with Considering Curvature

In the case of the style design based on a master model which is made by clay or wood, the production of the CAD model by fitting the measured point data has been bottleneck in the design process. This paper describes a new fitting method of 3-degree B-spline surface onto the dense measured point data. The method to determine knot location with taking account of curve length and curvature is proposed. And the parameter is set in consideration of the knot location. The master model with free form surface is measured by using the developed non-contact 3-D digitizing system. It is shown that the B-spline surface without waviness is fitted to the measured point data with high accuracy and in good condition.