Rosesat -- a Graphical Spacecraft Simulator for Rapid Prototyping

In the early system definition phase of any spacecraft development project there are few known parameters and many assumptions. Finding the optimum solution, from the wide variety of available technologies and techniques, is an onerous task for the development team who, for the sake of efficiency, depend on available analysis and simulation tools. While providing good support in the specific domains to which they are focused, these tools are generally poor in providing a total system perspective, in particular an end-to-end simulation. This paper discusses the use of a rapid prototyping tool, “ROSESAT ”, that provides quick access to the realization of the proposed system through simulation. Together with the generic object libraries provided, ROSESAT enables the development team to quickly configure end-to-end simulations of desired spacecraft missions. The paper begins with an introduction followed by a step-by-step discussion of the rapid prototyping exercise. Examples are enumerated through representative spacecraft system schematics. The ability to quickly reconfigure various subsystem components to evaluate the system performance is demonstrated. This exercise culminates in a baseline simulation of the spacecraft together with a matching system specification and schematic representations of each of the spacecraft sub-systems. It will be shown that the use of this baseline simulator supports design verification by helping eliminate the ambiguities associated with a text based description of the system requirements. These simulators provide a comprehensive working model of the spacecraft into which high fidelity models can quickly be developed, inserted and validated as the development cycle progresses. It will be described how the same simulator can support the entire development life cycle of the spacecraft and eventually become the mission operations support simulator. The paper concludes with a section on the experience CAE has gained on rapid prototyping using ROSESAT and the lessons learned in this process.