Journal of Mechanical Science and Technology

The Korean Society of Mechanical Engineers (대한기계학회)
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Weight Control and Knot Placement for Rational B-spline Curve Interpolation

  • Kim, Tae-Wan (Computer Aided Design and Analysis Laboratory, School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Lee, Kunwoo (Computer Aided Design and Analysis Laboratory, School of Mechanical and Aerospace Engineering, Seoul National University)
  • Published : 2001.02.01
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Abstract

We consider an interpolation problem with nonuniform rational B-spline curves given ordered data points. The existing approaches assume that weight for each point is available. But, it is not the case in practical applications. Schneider suggested a method which interpolates data points by automatically determining the weight of each control point. However, a drawback of Schneiders approach is that there is no guarantee of avoiding undesired poles; avoiding negative weights. Based on a quadratic programming technique, we use the weights of the control points for interpolating additional data. The weights are restricted to appropriate intervals; this guarantees the regularity of the interpolating curve. In a addition, a knot placement is proposed for pleasing interpolation. In comparison with integral B-spline interpolation, the proposed scheme leads to B-spline curves with fewer control points.

Keywords

References

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