AN ALGEBRA FOR MODELING ASSEMBLY TASKS

In this paper we develop a systematic approach to mechanical assembly which allows rigorous reasoning and is sufficiently general so that it is applicable to different kinds of assemblies. The paper presents a representation scheme based on attribute graphs for describing assembl y parts and an algebra to model assembly tasks. Any task is modelled a s a merging of two attribute graphs to produce a single attribute grap h which represents the merged or assembled object. The paper introduce s a number of different types of merging operations and their mathemat ical properties are of particular interest in the assembly context. Th ese two aspects of assembly, namely the representation scheme to descr ibe assembly objects and the framework to model assembly tasks, form m ajor components of an assembly planner. Due to its generic, formal and systematic nature, the framework is applicable to the assembly of dif ferent kinds of products, thus making the proposed scheme particularly attractive for flexible assembly systems.