基于特征面向装配规划的装配方向自动求解方法

Research on automated calculation of assembly direction for feature based assembly process planning

为自动求解装配规划中零部件的装配方向，利用了特征造型平台，通过指定装配体中零部件间的配合特征元素，建立了产品的装配模型。利用装配模型中零部件的配合特征几何元素的构造过程信息，通过提取装配模型中零部件间的配合特征几何元素的构造坐标系，以坐标轴方向作为零件的装配方向。若装配体中零部件具有多个配合特征元素，则以零部件配合特征元素集所确定的装配方向集的交集作为零部件的装配方向。该方法被用于装配序列的自动求解，实践表明，该方法能自动求解各种构型零件的装配方向。

In order to get the components' assembly directions automatically for assembly planning, a feature based modeling system to establish products' assembly models is used, by means of specifying mating elements among components. This paper proposes a method for determining the assembly direction of components, which uses the direction of the axis vectors as components' assembly directions. The constructing coordinate systems of the mating feature geometric elements among components within the assembly model are extracted to get the axis vectors. If there exist more than one mating elements among components, intersection of the direction set determined by the mating element set among the components is used as components' assembly directions. This approach is used in assembly process planning, and it is proved to be capable of calculating assembly directions for all kinds of components.