Control of lines of curvature for plate forming in shipbuilding

Masahito Takezawa, Kohei Matsuo, Takashi Maekawa

Research output: Contribution to journalArticle

Abstract

A ship hull consists of smooth streamlined surfaces satisfying hydrodynamic characteristics such as frictional, pressure, and wave resistances. It contains doubly curved surfaces particularly at the bow and stern. In shipbuilding, surface plates are formed by the mixture of cold and hot bending, which is typically called line heating. An efficient plate forming method based on the lines of curvature has recently garnered the attention of researchers. The initial shape of the plate to be cut, amount of bending angle for cold bending, and amount of contraction for line heating can be determined by flattening the doubly curved surface along the lines of curvature. However, the method suffers if the lines of curvature are wavy, or pass near the umbilical points. We herein propose novel methods for smoothing the lines of curvature and sweeping out the umbilics from each partitioned plate by deforming the surface within a prescribed deviation from the designed surface based on nonlinear optimization. We demonstrated the effectiveness of our proposed method by applying it to the bow of a bulk carrier, which was provided by a shipbuilding yard.

Original languageEnglish
Article number101785
JournalComputer Aided Geometric Design
Volume75
DOIs
Publication statusPublished - 2019 Nov

Fingerprint

Shipbuilding
Curvature
Line
Curved Surface
Heating
Hulls (ship)
Sweeping
Smooth surface
Nonlinear Optimization
Ship
Smoothing
Contraction
Hydrodynamics
Deviation
Ships
Angle

Keywords

  • B-spline surface
  • Lines of curvature
  • Nonlinear optimization
  • Plate forming
  • Principal direction field

ASJC Scopus subject areas

  • Modelling and Simulation
  • Automotive Engineering
  • Aerospace Engineering
  • Computer Graphics and Computer-Aided Design

Cite this

Control of lines of curvature for plate forming in shipbuilding. / Takezawa, Masahito; Matsuo, Kohei; Maekawa, Takashi.

In: Computer Aided Geometric Design, Vol. 75, 101785, 11.2019.

Research output: Contribution to journalArticle

Takezawa, Masahito ; Matsuo, Kohei ; Maekawa, Takashi. / Control of lines of curvature for plate forming in shipbuilding. In: Computer Aided Geometric Design. 2019 ; Vol. 75.
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