CMM离线检测在逆向设计模型改进中的应用

目前逆向工程主要采用逆向设计软件和CAD系统（如Geomagic，UG等）对点云进行拟合，并以此来评估几何型面拟合误差，而对设计模型的配合型面位置约束检测方法的研究则相对缺乏。为了在设计早期就能提前发现逆向设计模型的缺陷并进行改进，提出用精密三坐标测量软件离线检测逆向设计模型配合型面间空间约束的方法，讨论了逆向设计B-Rep模型的几何封闭性问题和制造工艺性（特别是装配要求）问题场景，给出装配约束型面间位置约束检测与缺陷改进的方法，最后用实例进行了说明，为现有的逆向设计模型质量检验和改进方法提供了一种有益补充。

Application of CMM Offline Inspection in Reverse Design Model Improvement

At present,reverse engineering mainly uses professional reverse design software and CAD systems (such as Geomagic and UG,etc.) to fit the point cloud of the reversed part and use this to evaluate the geometrical profile (including surfaces,etc.) fitting error.However,the discussion for the target geometric models position constraints validation,which has the mating relationship,is relatively lacking.In order to detect the defects of reverse design model and improve them in early design stage,the method of reverse design model mating with interplane space constraints was proposed using precision coordinate measurement machine(CMM) software in the offline inspection.The geometric closure and manufacturing process (especially assembly requirements) problem scenarios of the reverse design boundary representative(B-Rep) model were discussed;the method of position constraint detection in assembly constraint faces and the defect improvement were given out.Finally,it was illustrated with some examples.The proposed method provides a valuable supplement to quality inspection and improvement methods of the existing reverse design model.