The Cassini Spacecraft: Object Oriented Flight Control Software

The Cassini AACS object-oriented Flight Software is depicted in increasing levels of detail using a Context Diagram, Architecture Diagrams, an Object Diagram for each object, and a Statechart for each object. The detail contained in the diagrams is enhanced and refined during the Requirements and Design Phases of both Subsystem and Software Development. Examples of all the diagrams as well as the criteria for object selection, the advantages of statecharts, and the ease of modifying the design to accommodate changes in scope are described.