A component framework for satellite on-board software

This paper advocates a new approach to satellite software design based on object-oriented framework technology and describes early results from a project for the European Space Agency (ESA) to design a software framework for satellite attitude and orbit control systems (AOCS). Frameworks are collections of components with pre-defined cooperations among them. They make architecture (as opposed to mere code) reuse possible. The framework concept is being tested in a redesign of the AOCS software. This paper illustrates it by describing the implementation of telecommand handling, telemetry handling, and operational mode management.