Implementation of a Plug-and-Play attitude determination and control system on PnPSat

Plug and play satellite (PnPSat) is an Air Force Research Laboratory (AFRL) technology demonstration spacecraft developed to provide flight validation of the viability of AFRL´s PnP architecture and technologies. Microcosm and its partner HRP Systems have led the development of the PnP attitude determination and control system (ADCS) as part of the definition and implementation of the flight software (FSW) for PnPSat. This paper provide an overview of the PnPSat FSW architecture focused on ADCS implications, followed by a summary of ground-based testing results. PnPSat ADCS development has been challenged by both an accelerated implementation timeline and the requirements of the AFRL PnP architecture. However, the development of the PnP FSW has been true to the original goals and objectives of the PnP architecture, which focuses on a data centric system that abstracts the source and destination of information, highlighting the use of data elements. The evaluation of this first end-to-end flight implementation of PnP ADCS, established during assembly, integration, and test (AI&T) in the AFRL responsive space testbed (RST), has verified the validity of the approach. The performance drivers have also been elevated to specific hardware components selected to be part of the system. Given high performance sensors and actuators, the PnP infrastructure may become the bottleneck to creating a high performance ADCS implementation. This bottleneck can be avoided by incorporating the specific lessons learned from on-going flight-software-in-the-loop (FSWIL) testing, along with the potential on-orbit evaluation. Thus, the promise of rapid integration and flight software deployment for future PnP enabled spacecraft will be fulfilled.