树脂叶片出模后由于内应力的释放易导致其出现弯扭变形,为此在模具设计过程中必须对叶片变形进行补偿.点到点的变形补偿方式广泛应用于模具型腔优化设计流程,涉及2个主要问题:对应点的搜索及变形的表征.常用的基于迭代最近点(ICP)算法的对应点搜索方法无法处理较大变形或者是非刚体的情况;同时,基于离散矢量的变形表征方式容易出现局部重构变形.针对上述两问题,论文提出并研究了一种基于仿射配准的模具型腔反变形优化方法,并建立了与之对应的变形补偿模型.通过仿射变换消除非刚体的影响,同时将变形量表征为光滑的空间变换矩阵,实现了变形的精确补偿.仿真实验结果表明文中方法可以有效减小树脂叶片的弯扭变形,其中叶片最大变形量已由优化前的2.3360 mm降低至0.1689 mm;二维偏差平均值已由0.4962 mm降低至0.0568 mm,减小了88.6%.%A resin blade trends to have a torsion and bending deformation accompanying with the release of its in -ternal stress after being demoulded .Thus, it is in great need to compensate for its deformation during the mold de-sign.The point-to-point deformation compensation method , which is widely used in mold cavity optimization , in-volves two main problems: searching the corresponding points and characterizing the deformation . The corresponding point search method based on the iteration closest point ( ICP ) algorithm is not applicable if the de-formation is large or the model is a non-rigid body; In addition, the local reconstruction deformation often occurs when characterizing the deformation by discrete vectors .To solve these two aforementioned problems , a reverse de-formation method based on affine transformation is presented to optimize the mold cavity , and the corresponding de-formation compensation model is established .The effect of non-rigid body is eliminated by affine transformation , and the deformation is expressed as a smooth spatial transformation matrix which realizes a precise compensation for deformation.The simulation results show that the maximum deviation of the optimized blade decreases from 2. 3360mm to 0.1668mm and the two-dimensional standard deviation decreases from 0.4962mm to 0.0568mm, which confirms that the method can decrease the deformation of resin blade effectively .
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