表达式法在系列产品参数化CAD中的应用

根据不同系列军用改装车辆的特殊要求,需要对方舱结构进行频繁改动。为避免CAD模型的重复建立,本文应用两类表达式实现了改装车辆的方舱结构快速设计。首先建立了原型方舱零件及其装配的参数化模型,然后定义了驱动参数及其所有零件的装配关系表达式。通过关系表达式的驱动实现了方舱结构的尺寸参数化;通过抑制表达式实现了方舱结构形式的特征参数化。讨论了参数化设计与建模的关系,提出了零件参数化的表达策略。

Application of Expressions On Parametric CAD of Serialization Production

Shelter of serialization military vehicle is one subassembly need to be modified frequently according to different requirements. To avoid building CAD model repetitiously, two types of expressions are applied in the rapid reconstruction of CAD model for shelter alternation. Firstly, the parametric assembly model of prototype shelter was built. Then, both the driving parameters and the assembly relationship expressions of all parts were defined. Next, a kind of new shelter structure based on geometry parameterization was obtained by the relationship expression method, and other two kinds of transfigured shelter models were established by means of suppress expression method. Finally, the relationship between parametric design and modeling method, as well as the expression strategy, has been put forward.