Direct digital manufacturing: definition, evolution, and sustainability implications

One of the hot topics currently in manufacturing domain is direct digital manufacturing. With introduction of cheap three-dimensional printers, the direct digital manufacturing seems to become a new manufacturing paradigm with an entirely different impact on society; nevertheless how this will impact the society and the differences between the paradigms are unclear. According to this background, this paper presents a comprehensive analysis of direct digital manufacturing from different perspectives in comparison to various traditional manufacturing paradigms. Authors are using a societal viewpoint to see, describe and analyse the subject instead of traditional manufacturing viewpoint. For the better understanding of direct digital manufacturing origins, a classification and historical background about available techniques are described. Furthermore, direct digital manufacturing as a paradigm is analysed and compared with craft production, mass production and mass customisation. Direct digital manufacturing's sustainability aspects related to social, economical and environmental dimensions are gathered and analysed for a better insight of this technique. A detailed case study demonstrates the energy use differences of direct digital manufacturing and mass production in depth. According to the present work, direct digital manufacturing has the possibility of combining the advantages of the other production paradigms and can have a positive impact on sustainable development; yet, there are several challenges to overcome both in technical and sociality aspects. A challenge within the social aspects can be the life style changes which can impact the job market, working environment, waste management and more

Economic evaluation of environmental impacts of industrial products

Environmental costs of products are closely related to their environmental impacts incurred at all life cycle stages of a product. Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) methods are often used to estimate these environmental costs and impacts. However, LCA analysis is known to be a costly and time-consuming method, whereas LCC analysis often neglects the social cost which is currently paid by society as a whole. Therefore, this research proposes a new methodology to assess the environmental impact and social cost for the entire life cycle of a product, which can be used as a simple and transparent tool for the early conceptual design stage. The methodology delivers the Environmental Impact Drivers and the associated Social Cost Drivers for all product life cycle stages via spreadsheets, and it provides the Life Cycle Impact Assessment (LCIA) method in the SimaPro software as a user interface. Furthermore, the drivers provide the values for four different geographical regions and damage categories. The conceptual model is based on the impact pathway approach which integrates the Simplified LCA (SLCA) model and the social cost databases. The SLCA model is derived from an extension of previous research whereas the social costs are based on the most suitable Economic Valuation (EV) studies such as the EPS2000d, EXMOD, Ecosense and Asian EV studies. The data collection for the SLCA database was accomplished by using the LCA analysis of the Eco Indicator 99 H/A method and the Hierarchical clustering technique. The data for the social cost database was collected using the Benefit Transfer Method which obtains the EV studies mainly from the Environmental Valuation Reference Inventory (EVRI) data source. Several case studies utilising existing products, including a product redesign case study were used to prove the concept and demonstrate the efficiency of this proposed methodology