重建的一个方法对称的 B 花键曲线和表面被介绍。对称性质被使用对称的结向量和对称的控制点认识到。第一，数据点基于从数据点提取的对称轴或对称飞机被划分成二部分。当时，划分数据点是 parameterized，对称的结向量被选择以便得到对称的 B 花键基础功能。关于控制点的限制方程被推出保留 B 花键曲线或表面的控制点关于提取对称轴或对称飞机对称。最后，抑制最小平方试穿问题更多样地与 Lagrange 被解决方法。从工业的 Twoexamples 被给证明建议方法有效、柔韧、有能力满足一般工程要求。
For reconstructing a freeform feature from point cloud, a deformation-based method is proposed in this paper. The freeform feature consists of a secondary surface and a blending surface. The secondary surface plays a role in substituting a local region of a given primary surface. The blending surface acts as a bridge to smoothly connect the unchanged region of the primary surface with the secondary surface. The secondary surface is generated by surface deformation subjected to line constraints, i.e., character lines and limiting lines, not designed by conventional methods. The lines are used to represent the underlying informa-tion of the freeform feature in point cloud, where the character lines depict the feature’s shape, and the limiting lines determine its location and orientation. The configuration of the character lines and the extraction of the limiting lines are discussed in detail. The blending surface is designed by the traditional modeling method, whose intrinsic parameters are recovered from point cloud through a series of steps, namely, point cloud slicing, circle fitting and regression analysis. The proposed method is used not only to effectively and efficiently reconstruct the freeform feature, but also to modify it by manipulating the line constraints. Typical examples are given to verify our method.
