Description: In the near future we will see the development of space mission architectures where multiple spacecraft work cooperatively as a cluster to achieve mission objectives. Fault management (FM) is a critical challenge that must be addressed, especially when multiple spacecraft are working in proximity. Automatic fault management reduces the effort required by the ground crew when faults occur, and it reduces the chance of collision by quickly recovering from faults. We are developing a Flexible Fault Manager for Distributed Systems (FFMDS) for these missions. FFMDS is a FM architecture that will include algorithms to be run on each cluster module for fault detection, isolation, and recovery; software to be used at a ground station to direct recovery actions; and protocols for communication of fault information between cluster modules and between modules and the ground station. The architecture is service-oriented, so that algorithms for fault detection, isolation, and recovery can be added to or subtracted from the system as appropriate.

Benefits: The proposed fault management (FM) architecture will improve the robustness and survivability of multi-spacecraft missions. The numerous nano-satellite demonstrations within NASA are potential targets for this technology. Although the launch dates of funded demonstrations are too early for our timeline, there will be further interest in nano-satellites. The Cyclone Global Navigation Satellite System (CYGNSS) is a cooperative spacecraft mission that launches after Phase II. Other applications include spacecraft that assemble large space structures, such as a manned mission where an Orion MPCV docks with another Orion MPCV. These low Earth orbit demonstrations are critical to expanding human space flight.

The fault management (FM) architecture development augments the Cluster Flight Application (CFA) that Emergent is developing under DARPA's System F6 project. The CFA is focused on guidance, navigation and control software to support cluster flight. The CFA and this fault management architecture have significant potential for reuse on clustered spacecraft missions in the future. DARPA is currently looking for options to demonstrate technologies developed under the System F6 program. Any such demonstration of CFA could also host FFMACF. In a few years commercial manned spacecraft will dock with the ISS or other commercial space stations. Commercial systems are sensitive to size, weight, power, and cost. Rendezvous-capable vehicles at any scale will benefit from FM enhancements. The applications for our FFMDS are not limited to space. Non-space applications include groups of UAVs, groups of marine vessels, and autonomous transportation vehicles. All missions involving automation of multiple vehicles are potential commercialization targets.