Disassembling two-dimensional composite parts via translations

  • Doron Nussbaum
  • Jörg-R. Sack
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 401)


This paper deals with the computational complexity of disassembling 2-dimensional composite parts (comprised of simple polygons) via collision-free translations. The first result of this paper is an O(Mn + M log M) algorithm for computing a sequence of translations (performed in a common direction) to disassemble composite parts. The algorithm improves on the O(Mn log Mn) bound previously established for this problem and is easily seen to be optimal. The algorithm solves the problem posed by Nurmi and by Toussaint.

The second result of this paper is an Ω(Mn + M log M) lower bound proof for the problem of detecting whether a composite part can be disassembled, or contains interlocking subparts. Thus, detecting the existence of a disassembly sequence is as hard as computing one. As a consequence, the algorithm for computing a disassembly sequence is optimal also for the detecting problem.


Convex Polygon Linear Extension Composite Part Simple Polygon Visibility Hull 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • Doron Nussbaum
    • 1
  • Jörg-R. Sack
    • 2
  1. 1.Tydac Technologies Inc.Ottawa
  2. 2.School of Computer ScienceCarleton UniversityOttawaCanada

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