Case-Based Process Planning with Hierarchical Process Plan Merging

Michael M. Marefat and John M. Britanik

Department of Electrical and Computer Engineering
University of Arizona
Tucson, Arizona 85721

Email: { marefat,britanik} @ece.arizona.edu

Abstract

This research focuses on the development of (1) a case-based process planner which combines the advantages of the variant and generative approaches to process planning, and (2) a systematic hierarchical plan merging mechanism. The case-based process planner operates on general 3D prismatic parts, represented by a collection of features (eg: slots, pockets, holes, etc.). Feature subplans are merged into a global plan with a minimized number of fixtures and toolings using a hierarchical plan graph. Abstracted feature subplans correspond to cases, which are used in subsequent planning operations to solve new planning problems. The abstracting and storing of feature subplans as cases is a mechanism by which the planner learns from its previous experiences to become more effective and efficient.