A hierarchical Petri net framework for the representation and analysis of assembly

This paper uses Petri nets as a representation and analysis framework for automated assembly. It shows how the hierarchical nature of assembly is captured by Petri nets in representing assembly plans and lower level control plans. The tasks in a control plan correspond to assembly robot operations and can be viewed as a lower level representation of tasks at the assembly plan level. Petri nets provide a single unified framework for representing the hierarchical nature of assembly. This paper presents an approach to deriving performance and throughput measures of assembly on the basis of critical path analysis of the Petri net representation of plans