Determining knots by minimizing second derivative vector
基于极小化二阶导矢确定节点

One of key problems of constructing parametric fitting curves is to compute a knot for each point. A new method for determining knots was presented. Corresponding to each data point, the new method constructed a quadratic curve that passed three consecutive points; the knots of the quadratic curve were determined by minimizing the second derivative vector of the curve. The knot interval between two adjacent points was determined by the two quadratic curves. The new method determined the knots with a local way, which made it useful in interactive design of curve and surface. The experimental results in this paper show that the new method is more effective than the other existing methods.