基于实物的复杂曲面零件反求工程中未知区域测量数据补充及曲面重构技术

MEASURED DATA SUPPLEMENT AND SURFACE RECONSTRUCTION IN REVERSE ENGINEERING OF SCULPTURE SURFACE

针对基于实物的复杂零件反求工程中含有部分形状未知区域（如裁减曲面中的被裁减部分、测量盲区等）的复杂曲面反求CAD建模问题,提出了三种测量数据补充方法:①局部区域实物填充法。②补充设计数据补充法。③基于逼近曲面或三角曲面的测量数据自动补充法。研究了基于三角曲面模型初始表达的复杂曲面分区NURBS曲面重构方法。最后,给出了结合上述方法和反求工程软件RE-SOFT所解决的摩托车塑料件反求CAD建模实例。实践表明,综合运用所提出的数据补充和曲面重构方法,能够大大缩短实物样件的反求CAD建模时间,提高复杂曲面产品的设计效率。

Three measured data supplement methods are presented for reverse engineering of sculpture surface with unknown regions (such as trimmed region or unreachable re-gion).They are ①mending the unknown region of the practical part manually with some solid material before measuring, ②ending the unknown region of the measured data-cloud by designed surface according its surrounding data, and ③ending the gap with triangular Bezier surface or fitting surface automatically. As well as, a NURBS surface reconstruction method is presented based on the initial representation of triangular Bezier surface. Finally, an example of reversing engineering of a motorcycle part is given to verify the efficiency of the presented methods.