An Evaluation Method of a Machined Shape with Free-form Surfaces Based on the Detection of Positional Vectors and Unit Normal Vectors

Hideki Aoyama, Takeshi Kishinami, Katsumasa Saito

Research output: Contribution to journalArticle


This paper proposes an evaluation method of a mechined shape with free-form surfaces and describes the basic way of thinking for the evaluation in which free-form surfaces are classified into a style surface and a function surface according to the application purpose. The evaluation items of a style surface and a function surface are determined as a unit normal vector and a positional vector respectively. The transformation from a designed shape to a machined shape is assumed as a model of a coordinate transformation, and the permitted transformations in the evaluations of a style surface and a function surface are clarified. The evaluation procedure based on the detection of positional vectors and unit normal vectors at sixteen arbitrary points on a patch of a machined surface is described in detail. In addition, the validity of the proposed evaluation method is examined by a computer simulation.

Original languageEnglish
Pages (from-to)1651-1657
Number of pages7
JournalJournal of the Japan Society for Precision Engineering
Issue number9
Publication statusPublished - 1991 Jan 1
Externally publishedYes



  • CAD
  • CAM
  • evaluation
  • free-form surface
  • machined shape
  • measurement
  • positional vector
  • style design
  • unit normal vector

ASJC Scopus subject areas

  • Mechanical Engineering

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