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Navigation validation using the distributed spacecraft modeling and simulation testbed

The concept of distributed spacecraft systems as a means to perform tasks beyond the capability of monolithic space systems, such as multipoint observation, coobservation, and other complex sensing operations, has resulted in significant implementation challenges in terms of testing and validation. The research described herein contributes to the development of distributed spacecraft systems by presenting a means to address the integration and testing of multiple spacecraft missions, and by detailing the development of the navigation component of the Distributed Spacecraft Modeling and Simulation Testbed. A well-defined integration and test methodology is particularly critical for multiple spacecraft systems due to the inherent complexity in verification of interspacecraft operations, in addition to validation of individual spacecraft system and subsystem functionality. This Testbed is a hybrid (hardware and software) distributed computing environment capable of high-fidelity modeling and simulation of distributed spacecraft missions. The fidelity of the Testbed is ensured by the integration of flight hardware and flight software for spacecraft orbit determination and autonomous navigation. The Testbed provides the means to test fundamental aspects of broad classes of distributed spacecraft missions by providing closed loop absolute and relative navigation in a scalable environment. Simulations of more than eight spacecraft have been implemented.