Introduction

There are compelling reasons to develop space instrumentation and systems: to employ them in space to contribute to our understanding of the space environment and the laws of physics, and to deploy them in space to perform functions to benefit society. Military, commercial, and research uses of space begin from the same basis, the ability to develop affordable and increasingly capable systems. The planning, developing, integrating, testing, launching, and operation of space systems constitute a systems engineering effort of profound proportions. Such an undertaking requires close coordination of disparate participants, whose requisite scientific, engineering, and management capabilities span a breadth of disciplines that continue to change at dramatic rates.

Space systems development is generally characterized by a broad range of requirements, procurement in small numbers, significant changes in the applicable technologies over the development cycle, launch costs that are a significant fraction of the total. costs,and the inability to access the space environment to effect repairs or upgrades. As a consequence, space systems are generally unique, robust, and reliable, with minimal mass and power.

This chapter discusses the process and techniques utilized to concurrently develop the different subsystems of a sophisticated space system. Concurrent development poses significant engineering and management challenges. With the goal being the overall success of the system, the essence of systems engineering is compromise and tradeoffs that are embodied in the often-quoted saying 'The best is the enemy of the good" (Voltaire, 1764).