System Engineering Management, 5th Edition

Chapter 3System Design Requirements

This chapter addresses total system design, which can be defined as “the systematic activity necessary, beginning with the identification of the user need, to the selling and delivery of a product that will satisfy that need—an activity that encompasses product, process, people, and organization.”¹ System design requirements evolve from the initial identification of a consumer/user need and are developed through the accomplishment of a feasibility analysis, the definition of system operational requirements and the maintenance concept, the development and prioritization of technical performance measures (TPMs), the accomplishment of a functional analysis, and the top-down allocation of requirements to the depth necessary. Given these basic requirements, the design process encompasses the activities of synthesis, analysis, and design optimization through the accomplishment of trade-off studies, and ultimately leads to the detail definition of the system configuration down to the component level. This is a continuous and iterative activity with the appropriate feedback, as illustrated in Figure 1.13. With the system configuration initially defined, the next step is assessment or validation through an ongoing test and evaluation effort, and any subsequent system design modification and refinement as necessary.

Figure 3.1 shows all of the basic functions in the system life cycle; design activities are included within each of the blocks in the figure. ...