1. Introduction
Process planning for metal cutting is among the most knowledge-
intensive activities in manufacturing. In this activity the
product information is mapped on to the available information
for the various existing manufacturing resources to determine
a plan of action to convert the raw material into the final
product [1].
This activity is currently supported by information technology
in the form of computer aided process planning [2]. A considerable
amount of research has been carried out to introduce more
intelligence into process planning [3]. Process planning relies on
manufacturing resource models to supply the necessary information
regarding the physical devices used for manufacturing [4].
In the state of the art, the nominal model of manufacturing
resources is used for process planning. The information contained
within this model, neither reflects the actual state of the resources,
nor does it reflect any policy constraints that have been
implemented in the manufacturing enterprise. This results in
generation of process plans that might not be entirely effective in
the context of the available resources and policies.
In this paper a STEP-compliant methodology for representing
resources is extended to allow the representation of machine tool
capability profiles in a time-based manner while enabling users to
define custom rules and policies. The extended data model can
support the information requirements for profiling techniques
such as prediction and online monitoring of resources as chosen by
the user. The advantages of the methodology and the augmented
model are then presented through the use of a case study. A
discussion on the possible implementations of the methodology is
then presented together with the conclusions derived from the
work