This research in the area of manufacturing automation is focused on the study of linking design and process control through automated process planning. Process planning is the task of determining manufacturing operations and sequences for making a piece part or assembly. It links the design, production planning and control, and manufacturing process control functions. Efforts are underway to study automated understanding of design models to extract manufacturable features from geometric models and to examine assembly planning and different functional modules for an intelligent process planning system. The overall goal is to develo principles for modeling manufacturing knowledge, for understanding CAD geometric models, and for generating automated CNC control codes.