Choosing proper relation weights in product architecture clustering : a literature review

This technical report was conducted at the department YMS - PDM & CAD (Product Data Management & Computer Aided Design) at Scania and at KTH Royal Institute of Technology in Stockholm, Sweden. The report serves as a part delivery of a PhD project, within the area of modularization and product description, performed by the author.Scania is one of the leading truck, bus and engine manufacturers in the world and is today a part of TRATON SE (owned by Volkswagen AG), which is one of the world’s largest vehicle manufacturing groups. Scania has a successful history in vehicle modularization and claims it is one of the most important reasons why they are a leading company today. However, the Scania product has over the last years been developed into a Cyber-Physical System (CPS), with embedded software in focus, demanding the modularization methodology to support this new dimension. There is also a growing market regarding offline and online services, which also generates new demands.Earlier published research within the presented PhD project identified that a structured methodology which supports the development of the product architecture was needed at Scania, mainly to manage the increasing technical complexity in the Cyber-Physical Systems. Hence, a new clustering based method for product modularization that integrates product complexity and company business strategies was proposed by the author. The new method was named Integrated Modularization Methodology (IMM) due to the integrated approach for identifying module candidates during the clustering stage.One of the main challenges when using any clustering based modularization approach is to determine proper relation weights (importance), including the reasons behind the weights, and how the weights affects the clustering results. Hence, the main purpose of this technical report was to systematically investigate possible aspects which may affect the product architecture and thereby the relation weights, i.e. the reasons to consider when choosing proper relation weights in the architecture clustering analysis.The results from the report indicate that the importance of the design requirements needs to be reflected in the chosen relation weights, given that the DSM-clustering result is sensitive to the relative relation weights.QC 20200128