A knowledge-based manufacturing and cost evaluation system for product design/re-design

Various research studies have concluded that most new design projects are actually re-design activities. This re-design may be for improvement or for reprovision of existing products. Most research efforts for providing computer tools for supporting conceptual or early design mainly concentrated on the design of new products. In practice manufacturing plans generated when an order was placed may quickly become out-dated as the manufacturing environment and constraints often change. It is therefore equally important to regenerate manufacturing plans and re-evaluate design every time a product is changed, redesigned or reordered. This project focuses on manufacturability analysis and provides re-design support for conceptual design of discrete single-piece mechanical parts with emphasis on machined processes. This limitation of implementing the prototype system for re-design activities is not a system design or methodology restriction. The condition has been imposed by the authors as a prelude to validating the system and its results. A novel hybrid approach using a combination of sequential flowchart logic and an expert system has been developed which uses a user-defined feature tree as the input for its analysis. The system allows the designer to estimate manufacturability according to criteria of time and cost, and also to explore different scenarios of parametric variation in the design. A case study has been presented to validate the system's practicality and usefulness.