Value Methods in Systems Engineering and Insight for Aircraft Design: A Survey

Value-based methods aim at optimizing the development of physical and abstract entities focusing on the enhancement of their value. Due to the polysemic nature of this word, several methodologies have been conceived since its first theorization in the engineering field. The number of approaches along with the intrinsic complexity of the term value itself contributed to creating a chaotic environment, with many promising methods but usually not tackling the entire problem of enhancing the full value of products, processes, and/or services. This is why a systematic literature review, centered on value-based methods developed in the field of mechanical engineering, has been proposed targeting a common theoretical framework from which to start to consolidate the enhancement of value during the conception, development, and deployment of engineering entities. Due to the fact that value is able to aggregate several criteria, this research work explores also the possibility of adopting value approaches to improve complex products or systems, focusing mainly on the aeronautical sector, considering that it is one of the fields where these methodologies have been applied mostly and consistently. The main results emerging from this review are lacks in terms of definitions both in the cases of value and value-based methodologies. This ends in the conception of several heterogeneous approaches, characterized by important deficiencies in their application to real case studies. That trend worsens if the aeronautical field is considered, where relatively simple systems were usually considered, despite the highly aggregative nature of value.