Development of complex products and production strategies using a multi-objective conceptual design approach

Conceptual design is a fundamental phase for developing optimal product configurations. During conceptual design, the degree of freedom in engineering choices can propose optimal solutions in terms of assembly, manufacturing, cost and material selection. Nevertheless, in current industrial practices, each aspect is analysed independently and a guided decision-making approach based on multi-objective criteria is missing. Multi-objective analysis is a way of combining each production aspect with the aim of choosing the best design option. The goal of this research work is to define a multi-objective design approach for the determination of optimal and feasible design options during the conceptual design phase. The approach is based on the concept of functional basis, module heuristics for defining product modules and the theory of multi-criteria decision-making for mathematical assessment of the best design option. The novelty of this approach lies in making the design process, currently based on company know-how and experience, systematic. A complex product (i.e. tool-holder carousel of a computer numerical control machine tool) is the case study used to assess the economic sustainability of different design options and to validate the proposed design workflow in a real manufacturing context. Different product modules have been re-designed and prototyped for comparing the assemblability, manufacturability and cost of the design solutions.