A network-based structural complexity metric for engineered complex systems

The complexity of today's highly engineered products is rooted in the interwoven architecture defined by its components and their interactions. Such structures can be viewed as the adjacency matrix of the associated dependency network representing the product architecture. To evaluate a complex system or to compare it to other systems, numerical assessment of its structural complexity is mandatory. In this paper, we develop a quantitative measure for structural complexity and apply the same to real-world engineered systems like gas turbine engine. It is observed that low topological complexity implies centralized architecture and it increases as one marches towards highly distributed architectures. We posit that the development cost varies non-linearly with structural complexity. Some empirical evidences of such behavior are presented from the literature and preliminary results from simple experiments involving assembly of simple structures strengthens our hypothesis.