Geometriae Dedicata

, Volume 53, Issue 2, pp 119–131 | Cite as

Immobilization of smooth convex figures

  • J. Bracho
  • L. Montejano
  • J. Urrutia


We establish a curvature criterion to decide whether three points immobilize a plane convex figure with smooth boundary. Then we use it to prove in the affirmative the convex case of Kuperberg's Conjecture. Namely, we prove that any convex figure with smooth boundary, different from a circular disk, can be immobilized with three points.

Mathematics Subject Classification (1991)



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Copyright information

© Kluwer Academic Publishers 1994

Authors and Affiliations

  • J. Bracho
    • 1
  • L. Montejano
    • 1
  • J. Urrutia
    • 1
    • 2
  1. 1.Instituto de MatemáticasUNAM, Circuito exterior, C.U.México D.F.México
  2. 2.Department of Computer ScienceUniversity of OttawaCanada

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