Journal of Zhejiang University-SCIENCE A

, Volume 8, Issue 4, pp 593–595 | Cite as

Vanishing torsion of parametric curves

  • Juhász Imre 


We consider the class of parametric curves that can be represented by combination of control points and basis functions. A control point is let vary while the rest is held fixed. It’s shown that the locus of the moving control point that yields points of zero torsion is the osculating plane of the corresponding discriminant curve at its point of the same parameter value. The special case is studied when the basis functions sum to one.

Key words

Parametric curve Torsion Discriminant curve 

CLC number



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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Juhász Imre 
    • 1
  1. 1.Department of Descriptive GeometryUniversity of MiskolcMiskolc-EgyetemvárosHungary

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