Process planning for reconfigurable manufacturing systems.

摘要

Today's dynamic market requires fast and responsive manufacturing systems, which led to the development of Reconfigurable Manufacturing Systems (RMS); a new manufacturing paradigm. The machine capabilities, in RMS, change with each configuration. RMS technological enablers allow machines to be designed around products and process plans to be reconfigured in response to changes in these products.;The developed approach was demonstrated and validated using two case studies based on examples from literature. It was applied to both RMS and Flexible manufacturing Systems (FMS) environment. The results showed that developed RMS Process Planning Approach is not limited to RMS and can be applied to other manufacturing systems as exemplified by FMS.;This research work advances the existing knowledge about process planning in the RMS domain with regards to macro-level process planning (sequencing, operation selection and selection of machines and their configurations). This work supports the process planner in the decision making activity of the machine assignment/selection and sequencing activities at the initial stages of manufacturing systems design and subsequent changes in products scope.;In order to achieve the goal of this work, "RMS Process Planning Approach" was developed. It consists of four stages, the first of which clusters operations that have to be performed together. The second step introduces a new procedure that maps product features to their required machine capabilities, which are represented by a kinematic chain-like format. Accordingly candidate capable machines and their corresponding configurations are identified. Optimal process plans are generated in the third stage using Genetic Algorithms (GAs) based on a novel constraint satisfaction procedure that ensures the feasibility of all produced plans. A novel rule-based semi-generative Computer Aided Process Plans Reconfiguration (CAPPR) approach is introduced in the final stage. It reconfigures existing process plans to accommodate for changes in product requirements and/or availability of system resources. The CAPPR approach minimizes the required hard-type reconfiguration on both system and machine levels by performing less costly soft-type reconfiguration to existing process plans.