Handling the Effects of Complexity in Space Elevator Requirements

Rebecca J. Giorcelli and Laura L. Pullum

Research and development for the Space Elevator is a significant systems engineering challenge. A formalized systems engineering management plan for requirements elicitation and management is critical to project success. Effective requirements elicitation techniques must address interpersonal dynamics and idiosyncratic differences that impede an accurate understanding of customer problem and potential solutions. Abstractions must be relayed from one person to the next as teams proceed from customer words and actions to design commitment. The diverse collection of knowledge, perspectives and differing interpretations within a systems design team, in addition to natural individual bias of selection and use of data, constrains humans as requirements specifiers. In this paper, Quality Function Deployment (QFD) and the Z-model are proposed as communication tools to facilitate the requirements management process. The ability to concurrently capture problem domain knowledge and solution domain knowledge using QFD is proposed as a catalyst for effective communication during requirements elicitation. The Z-model is employed to ensure areas of weakness related to inherent bias for different styles of data perception and decision-making among stakeholders are addressed. The systems engineers at the Institute for Scientific Research, Inc. employ these tools to supplement the Telelogic DOORS® requirements management application for Space Elevator requirements management.

Keywords: Systems engineering, requirements elicitation, requirements management, communication facilitation techniques