Design for Six Sigma in the Product Development Process Under a Sustainability Point of View: A Real-Life Case Study

The modern economic landscape, now more competitive than ever, compels companies to create increasingly innovative, cutting-edge, and cost-effective products. In this regard, the design and development phases play a crucial role, as they closely determine the final satisfaction of the customers. It follows from this the need for a structured approach to product development, which allows companies to identify product key characteristics, also useful when there is the need for carrying out the redesign of an existing product. This work provides the application of the Design For Six Sigma (DFSS) methodology to a real redesign case study, based on the improvement in a specific mountain bike model (baseline product). The final target is identifying the main criticalities and intervention areas for the bicycle, to provide valuable suggestions to designers and developers for creating a new product alternative characterised by an extended horizon to various markets. DFSS is applied to identify and optimise Critical-To-Quality (CTQ) features, aiming at making the project as responsive as possible to customers’ needs. More specifically, two main tasks are addressed. The first one is the application of the identify phase of the IDOV approach (Identify, Design, Optimise, Validate) to identify the most pertinent Voice of the Customers (VOCs) to be implemented in the product. The second main task is the analysis of the integrated product development process carried out through the Six Sigma (SS) methodology, to transform the VOCs into CTQs via the Quality Function Deployment 1 (QFD1) and to prioritise the CTQ to achieve design excellence. The identified improvement strategies are presented and critically discussed in relation to their potential to reduce the environmental impact of the overall Life Cycle (LC) of the product.