By leveraging the existing Model‐Based Systems Engineering (MBSE) infrastructure at JPL and adding a modest investment, the Europa Mission Concept Study made striking advances in mission concept capture and analysis. This effort has reaffirmed the importance of architecting and successfully harnessed the synergistic relationship of system modeling to mission architecting. It clearly demonstrated that MBSE can provide greater agility than traditional systems engineering methods. This paper will describe the successful application of MBSE in the dynamic environment of early mission formulation, the significant results produced and lessons learned in the process.

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Abstract-Small spacecraft are more highly resource-constrained by mass, power, volume, delivery timelines, and financial cost relative to their larger counterparts. Small spacecraft are operationally challenging because subsystem functions are coupled and constrained by the limited available commodities (e.g. data, energy, and access times to ground resources). Furthermore, additional operational complexities arise because small spacecraft components are physically integrated, which may yield thermal or radio frequency interference.In this paper, we extend our initial Model Based Systems Engineering (MBSE) framework developed for a small spacecraft mission by demonstrating the ability to model different behaviors and scenarios.We integrate several simulation tools to execute SysML-based behavior models, including subsystem functions and internal states of the spacecraft. We demonstrate utility of this approach to drive the system analysis and design process. We demonstrate applicability of the simulation environment to capture realistic spacecraft operational scenarios, which include energy collection, the data acquisition, and downloading to ground stations.The integrated modeling environment enables users to extract feasibility, performance, and robustness metrics. This enables visualization of both the physical states (e.g. position, attitude) and functional states (e.g. operating points of various subsystems) of the spacecraft for representative mission scenarios.The modeling approach presented in this paper offers spacecraft designers and operators the opportunity to assess the feasibility of vehicle and network parameters, as well as the feasibility of operational schedules. This will enable future missions to benefit from using these models throughout the full design, test, and fly cycle. In particular, vehicle and network parameters and schedules can be verified prior to being implemented, during mission operations, and can also be updated in near real-time with operational performance feedback.

Model-Based Systems Engineering is founded on the principle of a unified system model that can coordinate architecture, mechanical, electrical, software, verification, and other discipline-specific models across the system lifecycle. This vision of a Total System Model as the digital blueprint (or digital twin) of a system, federating models in multiple vendor tools and configuration-controlled repositories, has gained tremendous support from the practitioners. A software platform, Syndeia, developed by Intercax, provides capabilities for seamless model-based communication between systems engineering and X (where X = mechanical/electrical, simulation, PLM, ALM, project management, and other disciplines), replacing the existing document-centric approaches. This paper elaborates research and development performed by NASA JPL and Intercax for integrating system architecture models (SysML) and mechanical design models (CAD) with applications to the Europa Clipper Mission. Specifically, this paper demonstrates (1) seeding of mechanical design models from system specifications (SysML) as a starting point for mechanical design, (2) model-based connections between system and mechanical design parameters, including compare and bi-directional synchronization, (3) abstracting system architecture from mechanical assemblies for transitioning existing/old projects to a model-based systems approach, and (4) use of persistent, fine-grained connections between system architecture and mechanical design models for continuous verification and communication between the two disciplines. The paper also covers organizational, cultural, and technical challenges that need to be addressed for seamless integration between system architecture models and mechanical/electrical design models, as well as other disciplines.

Abstract. In May 2012 the Europa study team delivered to NASA the final reports on three distinct concepts for exploring Europa on a limited budget. The depth and quality of these reports have been widely praised by independent reviewers as well as by our sponsor. The application of Model Based Systems Engineering (MBSE) techniques is credited with enabling the team to study three quite different mission concepts for the resources normally sufficient to study only one or two. The Europa MBSE infusion itself has been awarded the NASA Systems Engineering Excellence Award in 2012. The Europa team is now preparing for its Mission Concept Review and has reaffirmed and strengthened the MBSE application. Significant new capabilities have been completed, most importantly the Powered Equipment List (PEL) and the computation of scenario-based power and energy margins. This paper provides an update on the continued successful application of MBSE in the dynamic environment of early mission formulation, the significant new results produced and several additional lessons learned in the process.