An activity layer is provided for the activity-driven, object-oriented
(ADOO) automatic product design shell within atop-down environment fo
r computer-based manufacturing systems. In the activity layer, a funct
ional treatment template at-an assembly level is first presented to ex
press a conversion from a functional-compliant view to an activity-com
pliant view. An activity container produced by the treatment ment temp
late is then applied to a procedure for the activity organization, whi
ch includes index determining, simple circuit circle searching, topolo
gical sorting, and subcycle decoupling. These identified and organized
activities are transferred into an integrated module with an object-o
riented class form. A geometrical metrical representation and feature-
based modeling are implemented by using these defined activities for f
urther applications in automatic manufacturing systems. The activity l
ayer in an intelligent automatic product design environment supports t
he activity-driven modeling through the functional treatment and activ
ity alternatives within an intelligent concurrent environment.