Supporting Requirements Management by Requirements-driven Product Modelling

Doctoral thesis, 2004

This research aims to develop and evaluate an integrated product lifecycle model to support requirements-driven product development. Requirements-driven product development emphasises that requirements define and set objectives for the product development process. Requirements management, on the other hand, is the process of identifying, formulating, allocating, verifying, and managing changes to a set of requirements. An integrated requirements-driven product lifecycle model has been developed for supporting systematic design and for estimating the impact of requirements and product design changes (using requirements traceability). The integrated product lifecycle model combines six types of models: requirements model, functions model, concept model, part structure, property models and product lifecycle models. It also connects them with tracelinks. The main contribution of this research is how to manage requirements traceability to support the estimation of the impact of requirements changes. Traceability makes it possible to identify how parts, tests, etc. are related to requirements. This provides a qualitative assurance of the impact. Requirements traceability can also be used for measuring any changes to product performance regarding proposed requirements changes. The integrated product lifecycle model integrates and utilises simulation and analysis models in order to provide engineering designers with a decision support for evaluating concept proposals and balancing product properties. The product lifecycle model has been implemented in systems engineering tool and tested in a real product development project. The test implementation showed that the product modelling concept is applicable to concept development projects, and it seems that the utilisation of the product lifecycle model contributes to improved product quality. Further, research studies in the automotive and defence material industries provided basic data for the introduction and use of computerised support for systematic design and requirements management. It resulted in a set of guidelines for business managers and others who are going to introduce design support tools, especially for requirements management.