The Satellite Data Model

The Satellite Data Model (SDM) is part of the Air Force Research Laboratory (AFRL) Responsive Space Testbed Initiative. It is a developing standard for rapid integration of hardware and software components in a satellite network. The SDM is a middleware software system providing self-configuration and self-discovery capabilities in multiprocessor networks of applications, sensors, and actuators. By allowing both software and hardware to selfdiscover and self-configure, the SDM supports rapid development and integration of satellite networks. The SDM is intended to provide a completely generalized device-application interface whereby applications can be written independently of their data sources and messaging and without knowledge of the final data consumers. Similarly, sensors and actuators can be built without concern for specific applications or what processes they will interact with. 1 The Responsive Satellite The primary goal of the Responsive Space Testbed Initiative of the AFRL is to support the construction of a functioning satellite in a six day window from conception to launch. The Satellite Data Model is a critical component of this effort. To achieve these aims, a large consortium of application and device developers is currently working together to produce SDM compatible subsystems that can be quickly integrated for rapid-response tactical satellites. In a six day window there is no opportunity for development or testing of software. To accomplish this six-day goal, the Satellite Data Model must support the development and testing of all software prior to the six-day integration with hardware and other software components. The Satellite Data Model software was written to perform the necessary auto-configuration and integration tasks for hardware and software components. The SDM also provides a generalized interface between components. An SDM-compliant component in the Responsive Space Testbed consists of a plug-and-play communications interface and the ability to describe data products, data and message formats, and controls in an xTEDS document. The component must then have sufficient intelligence to respond to standardized messaging from the SDM as the SDM serves as a broker between data sources and destinations.