Building SPA PnP Satellites

The space community, led by AFRL, started developing spacecraft plug and play concepts and standards in 2004 and has resulted in the Space Plug and play Avionics (SPA) Standards. AFRL has undertaken two efforts in small satellite development to both solidify the technology and to demonstrate the benefits. The Plug and Play Satellite (PnPSat) utilizes the SPA-S interface standard and demonstrated that rapid development, integration and testing is possible. The second effort is PnPSat-2 that uses the next generation of SPA components for a larger bus focused on ORS needs to make real the promise of custom performance at commodity prices. The SPA standard interface has proven critical to the development of design tools that both select (based upon performance requirements) and place (based upon restrictions such as mass and power balance) components. The Satellite Data Model (SDM) method of query and discovery enables the development of modular, single purpose applications that support autonomous flight software in a distributed computing system. The utilization of a data centric architecture (as opposed to component centric) insolates software developers from both specific hardware components and data network topology. The SPA standard interface reduces the need for many specialized test methods resulting in major reductions in test time. This paper will present the steps used in designing, building, and testing SPA PnP satellites.