Support for re-use of manufacturing experience in product development : from an aerospace perspective
Sammanfattning: Globalization, public environmental concern and government legislation are challenging the Swedish industry to be more efficient and increase its efforts in research and in the development of methods and tools for product development and production. Furthermore, the manufacturing industry is changing from producing solely hardware products towards the inclusion of services or soft offers to add more value for the customer. As a result, there are an increased number of stakeholders involved in the early phases of product development that has an interest in the products design and performance during its life cycle. This challenges the way we manage and share experience internally as well as between companies.The intellectual property of a company is a key asset when competing on the global market; hence, the ability to capitalize on experiences from a company’s development processes as well as products in use becomes increasingly important. Also, the European manufacturing industry and the EU commission conclude that the industry has to move from being "Resource-based" to "Knowledge based" to add more value and avoid competing solely on low-cost. It is recognized that an expensive manufacturing solution has a negative effect on a products total life cycle cost and the ability to earn profit. Hence, manufacturing processes is constantly a target for improvement efforts and experience gained in manufacturing has a potentially high impact on design decisions in new projects.The aim of the research presented here is to improve manufacturability and avoid reoccurrence of design flaws in ongoing or new projects. The research has provided a better understanding of the mechanisms for experience re-use and developed methods and tools for feedback of experience from the manufacturing phase back to the earlier phases in the products life cycle. The work has been carried out within two projects funded by the Swedish governmental agency for Innovation Systems and industry. The first project was DLP-E, Digitally Linked Processes with a focus on Experience re-use and the second project was Robust Machining, aiming for more robust machining processes within manufacturing.The research approach has been to combine the design research methodology and participatory action research. These methodologies together with an initial research question have guided the work:RQ: “How can experience from manufacturing processes be tied and reused to impact the governing product and process definition?”Branches within engineering research committed to his area are concurrent engineering and design for manufacturing although this has usually been limited to general rules of thumb and qualitative methods for designers. Recently however, statistical methods such as Design for Six Sigma and other methods for Robust Design are introduced to affect earlier phases of PD to achieve improved manufacturability.Knowledge Based Engineering (KBE), represents a technology that provide the means to capture and automatically re-use engineering knowledge in an engineering design environment. Methods and tools from this area have been used as an initial approach in this research. A functional product perspective puts a focus on the activity where the product is used rather than on the tangible product itself. From an experience feedback perspective, experience is gained during these activities and possibly re-used if there is a learning process.This thesis presents an initial descriptive case study at two manufacturing companies that provided a better understanding of current practices for experience re-use and identified factors that influenced the feedback of manufacturing experience in product development. Based on initial assumptions and the results from the first descriptive study, a theory on the mechanism for experience feedback and requirements on a manufacturing system was formulated in a prescriptive study. A second descriptive study utilized a prototype to identify if the theory was applicable in an industrial environment and if it addressed the factors it was supposed to address. The research has been an iterative process, whereas results from the descriptive studies have influenced new prescriptive studies, delivering methods and tools, which in turn have influenced the ongoing work at the company where the research was conducted.The main contribution from the research is a framework to support re-use of manufacturing experience. The framework decompose the multifaceted task of experience re-use by identifying typical activities involved in the feedback process and categorizing the “elements of experience” in terms of knowledge, information and data. Combined with an engineering process improvement approach, processes are streamlined and value is added to the product. KBE techniques are used to capture and re-use product and process knowledge in an integrated manner. The applicability of the result has been validated in descriptive studies as well as within company improvement efforts.The research supports a frontloading approach in product development by enabling manufacturing experience to have an impact on the design definition in the early phases of product development. As a consequence, the risk for costly re-design later on in a project is reduced.
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