基于FBS的可变功能机械设计变更传播过程及特性分析

Change propagation process and characteristic analysis of adaptable-function machine based on FBS

介绍了可变功能机械的基本概念及对机械产品进行可变功能设计和进行设计变更传播特性研究的意义.从机械产品概念设计的角度,基于"功能-行为-结构"(FBS)映射模型,分析了机械产品功能之间的关联性,并将功能关联性映射到行为和结构中,在此基础上建立变更设计流程图.通过分析结构体在结构和功能上的约束,得出结构体之间的3种约束关系.在结构体约束关系的基础上,建立结构体关联矩阵,用来描述结构体之间变更传播的可能性.归纳总结了几种典型的传播行为特性,并得出变更传播树模型,为更好选择变更传播路线奠定了理论基础.最后在FBS映射模型基础上对CA6140普通车床进行了数控改造,用传播行为过程图描述了具体零部件之间的变更传播,验证了变更传播分析方法在该映射模型上的可行性.

The concept of adaptable-function machine was introduced,together with the significance of redesigning mechanical product for adaptable functions and that of investigating its relevant change propagation characteristics.The incidence of functions among different adaptable functions was analyzed by means of function abstraction from the point of view of conceptual design,by which the structural and behavioral incidences could be investigated based on FBS.Based on these,a change-based design process flowchart was proposed.The propagation was analyzed by structural constraints and functional constraints,and three rules of the structural constraints were proposed,including the constitution relationship,the bidirectional relationship and the functional constraint relationship.The structural incidence matrix was investigated to describe the possibility of change propagation among different structures.Several typical behavioral characteristics were summarized about change propagation,together with the model of change propagation tree which provided the theoretical principle to choose the best change propagation route.Finally,a case study of redesigning the CA6140 machine tool towards being numerically controlled was provided,and the behavior process of change propagation was used to describe the propagation behavior of specific parts in order to validate the feasibility of the proposed analysis approach.