A Deep Dive into Axiomatic Design -- Part I: Problem Formulation

Problem formulation translating customer needs and constraints into a minimum set of independent first-level functional requirements, is arguably the most critical step in every design framework, including axiomatic design yet it is frequently misunderstood or underestimated in practice. This paper focuses exclusively on problem formulation in axiomatic design it clarifies what first-level FRs are (and are not), explains why they should not legitimately vary across designers given the same needs and constraints, and highlights intrinsic difficulties and recurring pitfalls that lead to design failure. The discussion is grounded primarily in Nam P.Suh's three books. The Principles of Design, Axiomatic Design Advances and Applications, and Complexity Theory, and it offers practical guidance to help designers formulate well-posed first-level FRs. Finally, the paper briefly revisits problem formulation in the era of large language models and discusses what such tools can (and cannot) contribute at the first level.