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摘要: 针对重大件货仿真系统中船体曲面造型问题, 给出了基于NURBS (非均匀有理B样条方法) 技术重构船体曲面的主要步骤。对于给定的船舶型值点, 用累加弦长参数化方法构造节点矢量, 用非均匀有理B样条方法进行横剖线和水线的全局插值, 并构造出规整的船体曲面的插值点网格, 进而重构出以NURBS为统一数学表达式的船体曲面。仿真结果表明应用NURBS方法重构出的三维船体具有高度真实感。
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关键词:
- 曲面重构 /
- 曲面插值 /
- 重大件货 /
- 非均匀有理B样条方法
Abstract: In allusion to the ship hull surface modelling in simulation system of loading and unloading awkward length cargo, this paper provided the main steps of reconstructing ship hull surface by NURBS (non-uniform rational B-spline). According to the points in offset table, the knot vector was calculated with an accumulative chord length parameterization, the global interpolative crosscut lines and waterlines were available with NURBS technology, and the regulative interpolative grid of ship surface was made, thus the ship surface presented with NURBS was reconstructed. The simulation results show that the 3-D ship hull surface reconstructed by NURBS is highly real, this method is feasible.-
Key words:
- hull surface reconstruction /
- surface interpolation /
- heavy and awkward article /
- NURBS
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