DISCUS is a generic Guidance, Navigation and Control (GNC) system for swarms of SmallSats. It integrates communications and relative localization with innovative Density Control Algorithms (DCA) enabling robust operation in a variety of uncertain environments. As such, it presents a key enabling technology for future Deep Space missions including space apertures at Lagrangian points, and orbiting missions at asteroids and faraway planets and moons.
The key aspect of DISCUS is tight integration of communications with relative localization and control. The proposed RF communications architecture provides a dual benefit since the RF signals are also used for relative localization based on ToA and TDoA sensing modes. Density Control approach is highly robust to failures of individual spacecraft and has the key property of self-healing, which allows for mission continuation even with a reduced capability. DCA are integrated with our effective collision detection and avoidance algorithms improving the overall system safety and efficiency. The contingency mitigation module monitors the health of the swarm and removes failed spacecraft in a safe manner. Proposed DISCUS algorithms were demonstrated in Phase I through computer simulations, as well as through initial flight tests at a UW Lab.
Phase II will focus on the following: (i) Further development of mission-related DISCUS requirements and metrics and a mission simulation; (ii) Further development and testing of the communications architecture, relative localization strategy and Density Control Algorithms; (iv) Further development and testing of the Collision Avoidance and Contingency Mitigation algorithms; (v) Hardware testing of the overall DISCUS system using quadcopters in the UW lab; and (vi) DISCUS software delivery to NASA. Phase II-X will focus on transition of the DISCUS technology to NASA missions.
DISCUS is applicable to future NASA Deep Space missions including space apertures at Lagrangian points, and orbiting missions at asteroids and faraway planets and moons. SmallSat swarms could be used to build Synthetic Aperture Radars, sparse aperture sensors, stellar interferometers, and global broadband internet. Swarms of SmallSats could also provide global real-time space weather monitoring, a survey of the geomagnetic field and its temporal evolution, and gain new insights into improving our knowledge of the Earth's interior and climate.
Due to lower costs of development and launch, several future commercial applications of SmallSat swarms such as remote sensing, on-orbit servicing, and sparse aperture imaging are viable. SmallSat swarms can be used for rapid communication and imaging tasks to provide situational awareness solutions needed by the Department of Defense, National Reconnaissance Office, and Department of Homeland Security. DISCUS will also have application in commercial Deep Space missions such as asteroid surveillance to locate areas where mining will be feasible and profitable.