Modular Spacecraft Standards: Supporting Low-Cost, Responsive Space

The long lead and cycle times currently associated with development and launch of satellite systems effectively preclude low-cost, responsive deployment of technology and tactical capability to orbit. To eliminate this obstacle, AeroAstro is developing SMARTBusTM, a novel spacecraft architecture based on the coordination of multiple predesigned functional modules. This paper describes the development of the mechanical, electrical, and logical interoperability standards to which SMARTBus modules must adhere. Designing a spacecraft using this architecture reduces to selecting the appropriate pre-qualified modules for their performance and functional characteristics and stacking them together. A standardized mechanical module design emphasizes a lightweight, interchangeable framework to enable configuration flexibility and rapid integration. The logical system developed for this architecture represents an enhancement to commercial “plug-and-play” connectivity, and will enable the vehicle to detect the presence and orientation of integrated modules. Control of the spacecraft and completion of mission objectives reduces to the dynamic allocation of on-board resources through prioritization of requests and responses among modules. While this modular assembly approach leads to a suboptimum design in some cases, it enables the assembly of a complete spacecraft on a budget and time scale that is impossible to achieve with the current method of custom spacecraft construction. Assembly, integration, and test of a spacecraft from off-the-shelf SMARTBus modules could be completed in a matter of hours.