The Space Plug-and-play Architecture (SPA) concept of rapid satellite development has progressed exponentially over the past several years. The team at the Configurable Space Microsystems Innovations and Applications Center (COSMIAC) in conjunction with the Space Dynamics Laboratory (SDL) and the Air Force Research Laboratory have trained over 500 individuals on this rapid bus architecture related to satellite development. This paper will outline the first CubeSat satellite proof of concept flight for a SPA only spacecraft. The Trailblazer mission is designed to fly a 1U CubeSat that is based entirely on a SPA bus implementation. Trailblazer will consist of Commercial Off The Shelf (COTS) parts converted to be SPA compliant. This allows not only a demonstration of the bus reliability in a space environment, but also the ease in converting existing components to be SPA compliant. With the dimensional constraints and power budget of Trailblazer, we have elected to use the SPA-1 standard. SPA-1 is the most recent addition to the AFRL SPA family. The SPA-1 data transfer protocol is based on 400 kbit/s I2C making it the lowest power, and lowest bandwidth option for SPA. Given the power constraints of typical satellite architecture, it is generally advantageous to interface devices/modules which do not require high data transfer rates to a SPA network via the SPA-1 Applique Sensor Interface Module (ASIM). This ASIM is logic that enables SPA Plug-and-Play for hardware components. It contains all the information needed for the system to automatically discover and automatically configure the hardware component. SPA-1 ASIMs can be any microcontroller that supports I2C and has enough memory to contain the needed logic. This allows the standard to remain open to a variety of dynamic implementations. The Trailblazer mission is being launched under the National Aeronautics and Space Administration (NASA) Educational Launch of Nanosatellite (ELaNA) program. This NASA program is designed to provide affordable access to space through collaborative efforts with academic institutions. The ELaNA program provides manifesting and launch of CubeSats for $30,000 per 1U module. The proposed orbit is 325 km with an inclination of 51 degrees for a launch in 2011.
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