Networking intelligent components to create intelligent spacecraft

Spacecraft utilize complex digital electronic controls to perform their missions. Although these systems have benefited from the availability of ever-faster computers and miniaturized electronics, overall control system architectures have changed little, utilizing a shared, centralized computer programmed to service many subsystems. These centralized systems perform well, but are a challenge to design and integrate, requiring complex custom software, custom I/O electronics and extensive vehicle wiring. The availability of microprocessors, memories and serial data terminals small and rugged enough to be embedded directly into subsystem mechanical components has opened the door to revolutionary new distributed architectures. These so-called “smart” or intelligent components can be interconnected into a network to form a distributed architecture. This paper discusses work done to define these distributed architectures and to construct prototype components. Important issues addressed include the physical network required to distribute data and power to components, highly reliable, fault-tolerant operation, the importance of industry standards and a discussion of packaging and installation considerations