New Constraint-Driven Mission Construct for Small Satellites and Constrained Missions

Small satellites, though increasingly prevalent in the industry today, tend to not follow traditional development paths, technically or programmatically. In contrast to traditional requirements-driven missions, where meeting requirements is the primary metric of success, small satellite missions tend to be constraints-driven, where mission scope is tradable to maintain cost and schedule constraints. There has not been a concise, fundamental outline of how small satellites - or more broadly, constraints-driven missions - are developed. This paper attempts to create that outline and define an alternative path from traditional requirements-driven (e.g. Class A - D) development frameworks. Stated another way, traditional practices are often not conducted on small satellite missions or constraints-driven missions simply “because it's a smallsat.” This paper attempts to better define the reasoning behind that philosophy, and how to apply it more methodically. The paper defines constraints-driven missions and how they are different from requirements-driven missions. The assumptions going into constrained missions are outlined along with details pertaining to why some programs need to be (or implicitly are) constrained. Then the overall construct for how to organize a constraints-driven mission is described and outlined. The construct is based on Agile software development concepts but is also derived from multiple programs and missions (big and small) that have gone through similar practices to achieve success. Fundamentally, the paper argues that for constrained missions, scope and requirements are tradable attributes. The method for understanding the requirements / constraints balance, recognizing divergence from that balance, identifying methods to address alterations, and then establishment of a new balance is outlined. Finally, an example of how this architecture can be implemented is provided.