保持形状特征的整体网格曲面变形算法

Global mesh deformation method with form features preserved

为了克服传统网格曲面变形对模型的特征只能进行近似控制的缺陷,提出一种精确的特征控制方法,使得模型特征在整体曲面变形中保持原有形状。首先提取形状特征的位置信息,将其作为变形过程中的刚性约束;再根据改进的离散拉普拉斯算子,建立反映网格曲面微分特性的柔性约束;对刚性约束条件引入拉格朗日乘子,结合柔性约束条件建立线性方程组,利用最小二乘法求出最优解,从而实现在保持形状特征的情况下网格曲面的整体变形。最后,通过实践应用证明了上述算法的合理有效性。

The traditional mesh deformation only approximates the form features.To overcome this shortcoming,one precise feature controlled method was proposed to preserve the form features in mesh deformation processing.Position information was firstly extracted to act as hard constraints for deformation.Based on refined discrete Laplace operator method,the soft constraints was established to mean mesh differential coefficient features.Introducing Lagrange multiplier to hard constraints,the linear equation was set up by combing with soft constraints.The optimal solution was obtained using least-squares method.The mesh was deformed preserving form features.Finally,the feasibility and effectiveness demonstrated by a practical engineering.