设计更改在装配关节图上的传播

Design Change Propagation in Assembly Joint Graph

设计更改的连锁反应效应可能导致不可预计的后果,为了更好地获取更改在零件间的传播过程,提出基于装配关节图的更改传播求解方法.装配关节图以机件内部所有与装配特征相关的几何特征为研究对象,零件间的连接关系和零件内几何特征间的空间关系分别用装配关节和变换矩阵表示;作用于几何特征的设计更改表达为特征坐标系下的变换矩阵,更改在关节图上的传播按机器人学中的正运动学问题求解,并在关节处根据自由度进行消解;在装配关节图上层层递进的更改传播求解与人工干预的更改方案的确定及实施交替进行.最后基于Pro/E平台二次开发的应用系统验证了该方法的可行性.

Knock on effects in design changes can lead to unexpected results. To acquire the propagation of changes among parts, a design change resolution method based on assembly joint graph （AJG） is proposed. AJG involves all geometry features associated with assembly features. Connections between parts are expressed as assembly joints, and the spatial relations among geometry features in the same part as transformation matrix. Changes on geometry features are denoted as transformation matrix in the geometry feature coordinate system, and propagation of the changes in AJG is solved as the forward kinematics in robotics, and is dissolved in the assembly joint according to DOF of the joint. The layer-by-layer recursively solving of change propagation in AJG and the implementation of change solution identified by manual intervention are performed by turns. The efficiency of this method is evaluated with the application developed based on Pro/E platform.