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Study of the Shape Optimization in Spline FEM Considering both NURBS Control Point Positions and Weights as Design Variables

NURBS 제어점의 위치 및 가중치를 설계변수로 하는 스플라인 유한요소법 기반 형상최적설계 연구

  • Song, Yeo-Ul (School of Mechanical, Aerospace and Systems Engineering, Division of Mechanical Engineering, KAIST) ;
  • Hur, Jun Young (School of Mechanical, Aerospace and Systems Engineering, Division of Mechanical Engineering, KAIST) ;
  • Youn, Sung-Kie (School of Mechanical, Aerospace and Systems Engineering, Division of Mechanical Engineering, KAIST)
  • Received : 2013.10.14
  • Accepted : 2014.01.27
  • Published : 2014.04.01

Abstract

A new NURBS-based shape optimization method is proposed. Most shape optimization studies consider only control point positions as design variables. Some shape optimization processes present problems with mesh quality and convergence when control points are constrained to a limited space. If the weights of the control points are regarded as additional design variables, it should be possible to attain a better degree of shape control. In this study, positions and weights of NURBS control points are used as design variables, and a shape optimization algorithm incorporates position optimization and weight optimization steps. This method is applied to shape optimization benchmarking problems to verify its advantages.

Keywords

Spline Finite Element Method;Shape Optimization;Non-Uniform Rational B-Spline;Control Point;Weight

Acknowledgement

Supported by : 한국연구재단

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