Database-Driven Concurrent Model-Based System Engineering for Space Mission and Systems Design

Model-based systems engineering (MBSE) is a model-centric system engineering approach for representing complex systems recently gaining attention and importance in space system design. Unlike traditional methods that rely on document-based specifications and drawings, MBSE relies on computer-based tools and procedures to enhance the design and verification process. It offers several benefits, including increased time and cost efficiency, better collaboration and communication, and reduced errors in documentation. In the space system and mission design framework, the space agencies such as NASA and ESA, the industry, and the Academia have been starting to apply MBSE successfully, demonstrating the method's advantages in system design. Furthermore, especially for phase 0-to-B space mission design, MBSE can be combined with another systematic approach, namely Concurrent Engineering. This approach to integrated product development reduces time to mission design and development costs while increasing the quality of the systems because tasks can be carried out in parallel with a quasi near-real-time teamwork . To support the successful implementation of Concurrent Engineering in an MBSE context, the use of a unified language and proper tools that enhance team cooperation is essential. Additionally, data exploitation for developing, analyzing, and validating the system is crucial and can be achieved through an effective data management system. In this framework, databases can effectively support data management and the overall space mission and systems design, thanks to a fast and ready-to-use data storage, retrieval, and management system. In fact, a database is a structured collection of organized information or data stored electronically in a computer system, where data is usually organized and processed in tables consisting of rows and columns. This structure enables efficient querying and processing of data, allowing for easy access, modification, updating, control, and organization of the information. Therefore, a well-structured database can support the Concurrent Model-Based practices during both the conceptual design phase, if it provides a mission and systems baseline to the design based on previous space missions, and the more advanced design/manufacturing/testing phases, if it offers a comprehensive catalog of commercially available components. A particularly effective representation of data can be obtained through Relational Database Management Systems (RDBMS) based on the Relational Theory (Edgar F. Codd , 1970) due to their ability to capture the mutual dependencies among database elements. In RDBMS data is stored in 2-dimensional tables where each row is labeled with a unique key which serves as a logical connector between tables. This structure helps to simplify the storage of a huge amount of data by breaking it into subsets while preserving the correlations among them. This paper presents a database architecture in MySQL, a Relational Database Management System (RDBMS), and a preliminary version and application examples, for supporting Concurrent Model-Based System Engineering (CE-MBSE) practices within the domain of space missions and space systems design, with a focus on the small-satellite missions. The paper describes the application of MySQL in facilitating the storage, retrieval, and management of data pertinent to the architecture of space systems to be employed during the preliminary design phases, namely phases 0 and A. In fact, during the conceptual design, this database can serve as a solid baseline for the conceptual and preliminary small-satellite mission and subsystems design, according to the stakeholders’ needs and technical constraints identified at the project kick-off. However, this database can also be used as a ‘customer’ database of Commercial-Off-The-Shelf (COTS) available on the market as a preliminary selection of the components in phases C and D. More in detail, 3 main hierarchical levels have been used to set up the database: (i) the mission level, (ii) the system level, and (iii) the component level. The mission level collects information such as the subject, the target body (Earth, Moon, Mars, Asteroids, etc.), and the mission applications (Earth Observation, Technological Demonstration, In-situ Resources Utilisation, etc.), together with main mission-related parameters (such as type of payload, overall cost, launchers, etc.) and architecture. The system level gathers all the available classes of satellites, from small satellites to pico-satellites, and contains information related to the high-level design constraints (maximum mass, volume, power propulsion availability, etc.) and possible system architectures already implemented. Finally, the component level is intended as a collection of COTS that characterize the satellite subsystems up to the component level, including the critical technical (physical, functional, power, thermal, etc.) and non-technical (country of origin, TRL, cost, etc.) parameters. The presented structure enables both top-down and bottom-up access to the database, as the user depending on their needs can either start by selecting a specific mission and progressing up to the component or they can visualize the components/systems for a set of specific technical requirements. Additionally, the user can add their mission, systems, and components details when new information comes out from the design itself, allowing for a knowledge transfer and collection of lessons learned.