Sarosh Talukdar, Jim Rehg, Rob Woodbury, Alberto Elfes
Design systems can have considerable embedded value. Improvements in such systems are better achieved through upgrades than through complete replacements. To determine how best to make these upgrades requires a systems view of design. Such a view is provided by what we call TAO (test-aspect-operator) graphs. Nodes in these graphs represent . aspects of the artifacts being designed while arcs represent operators (transforms between aspects) and tests (comparisons of aspects). Upgrades can be thought of as the additions of nodes or arcs to an existing TAO graph. To illustrate these ideas we will briefly describe the upgrades that we are making to a system for designing certain automobile parts.