AN OBJECT-ORIENTED MODELING FRAMEWORK FOR AUTOMATED MANUFACTURING SYSTEM

Proposed in the paper is an object-oriented modelling (OOM) framework, called a JR-net modelling framework, for automated manufacturing syst em (AIMS) design. The proposed modelling framework, which consists of a graphical modelling tool called JR-net (job resource relation-net) a nd a modelling building procedure, is the same as the current practice of AMS design and is based on the OOM paradigm. In other words, a vir tual prototype of AMS is constructed step-by step based on a three-pha se modelling approach: static layout modelling (object model); job flo w modelling (functional JR-net model); supervisory control modelling ( dynamic model). A functional JR-net model is a directed graph in which the standard resources of an AMS become nodes and job transfers among the resources become the arcs of the graph. A complete (dynamic) JR-n et model is obtained by specifying supervisory control requirements us ing tokens in the functional JR-net model. The usefulness of the propo sed OOM framework is demonstrated by applying it to the modelling of a n AS/RS. Also addressed are implementation issues of JR-net models.