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Virtual Mission Systems for Multi-Disciplinary Engineering System Design

To ensure the science return while minimizing the cost and risk of a mission, a lifecyclewide concurrent engineering design process must be established. This paper describes the Virtual Mission Operation Framework (VMOF), which provides distributed modeling, simulation, and visualization services. The goal of the VMOF is to enable concurrent design of a mission system and operation of that system by providing operational perspective to the system designers and system perspective to the operation designers. Concurrent development of the both perspectives requires interdisciplinary modeling and simulation of the mission-operation activities and the system architecture. The VMOF employs virtual mission systems to capture the dynamic interdependencies of the spacecraft system, the science payload, and the physical world throughout the lifecycle phases. A space science mission starts with a set of science questions about natural phenomena, and it transforms into specific measurement objectives and science-return requirements. The measurement objectives and science-return requirements drive the requirements for the mission operation, spacecraft system architecture, and instrument systems. To ensure the desired quantity and quality of the science data products while minimizing the cost and risk, a lifecycle-wide model-based engineering process that can easily adapt to a mission-specific science traceability matrix must be established. The lifecycle-wide model-based engineering process must also provide concurrent and collaborative system engineering among the instrument system, the spacecraft system, and the mission operation [1]. Mission lifecycle consists of three major phases, formulation, implementation, and operation. During the formulation phase, system-level designs are developed by performing various trade analyses among a wide range of options to ensure the optimality of the design with respect to the mission objectives and project resources. During the implementation phase, the subsystems are designed, developed and verified against the system-level design. The subsystems are then integrated and tested for operation readiness. During the operation phase, the flight system is launched and the spacecraft is navigated, controlled, and monitored toward the science targets. After a successful encounter, various telemetry data are collected from the science payload systems, engineering and science data products are developed, and finally scientific discoveries are shared with the general public. In order for a mission to be successful, everyone must work together toward the same mission objectives and clearly understand his/her role in achieving those objectives. The challenges in providing a lifecycle-wide continuity to all mission teams are enormous due to the typical long duration of a mission lifecycle, the multiple engineering teams