The recently launched OPS-SAT mission is the first CubeSat mission designed by ESA, with the ambitious goal to provide a low-cost, open and flexible flying ‘laboratory’ – a powerful platform for in-orbit demonstration of new, innovative control systems and software. This is achieved through a novel system architecture consisting of both off-the-shelf components and custom development to enable a service oriented architecture (using the CCSDS Mission Operations Services framework). The orbiting test-bed includes many subsystems including an experimental computer and processing platform, AOCS, GPS module, S- and X-band communications payloads, a high-resolution camera, optical uplink receiver and a software-defined radio front end. The project team is large and diverse, consisting of both academic and industrial stakeholders. This combination of complexity and diversity resulted in several systems engineering challenges, including common understanding and communication of complex concepts, adherence to an agreed baseline, configuration control and changes to the system architecture late in the engineering lifecycle. The project feasibility was determined by a Concurrent Design Facility study in 2012, thus an analysis may be performed on the output of that study and the current architecture. In the future, experimenter users could greatly benefit from understanding of the system via a formal system model also for experiment integration and feasibility analysis. Next-generation developments of similar in-orbit demonstration missions are already foreseen. All of these factors make the mission a highly suitable candidate as an end-to-end demonstration and use case for application of MBSE. This idea is to reverse-engineer the OPS-SAT system utilising a selected MBSE approach (and tools). The modelling aim shall be to alleviate previously encountered pain points and to provide a reference model from which future IOD missions can be prepared utilising an MBSE approach.
