October 5-9, 2014

Abstract

P2.10 Flexible and Modular Design for the BepiColombo Science Operations Control System

Juan Carlos Vallejo (ESA/ESAC)

Fernando Perez-Lopez (ESA/ESAC), Inaki Ortiz de Landaluce (ESA/ESAC), Alan Macfarlane (ESA/ESAC), Pedro Osuna (ESA/ESAC), Ranpal Gill (ESA/ESAC), Mauro Casale (ESA/ESAC)

BepiColombo is an interdisciplinary ESA mission to explore the planet Mercury in cooperation with JAXA. The mission consists of two separate orbiters, the ESA’s Mercury Planetary Orbiter (MPO) and the JAXA’s Mercury Magnetospheric Orbiter (MMO). The MPO scientific payload comprises 11 instruments covering different scientific disciplines developed by several European teams. The MPO science operations will be prepared by the MPO Science Ground Segment (SGS), located at the European Space Astronomy Centre (ESAC) in Madrid, Spain. The BepiColombo Science Operations Control System (BSCS) is the set of systems required for conducting the Science Operations at the SGS, including the data processing pipelines. The design has been completed and the implementation is on-going. It follows a modular and flexible approach based on past experiences from other missions. This paper describes such an approach, selected based on the main drivers of the project. One of these is the software heterogeneity. The available resources for the implementation are quite tight. There is no single team delivering the software. The SGS will co-develop with some instrument teams part of their pipeline software, and, in other cases, will be only responsible for the software integration and the BepiColombo Archive Core Subsystem (BACS) will be under the full responsibility of the mission independent Science Archives and VO Team (SAT) at ESAC. A second driver is the extended project lifetime, with an implementation split in two stages: some functionality of the BSCS will be ready at Launch (2016) and other functionality needs to be ready at Mercury arrival (2024). Apart from this, the software technologies evolve continuously in shorter timescales, and the selected design must cope with this. The system should cope with these changes from the design to the final implemented system. Finally, personnel evolve, and expertise should not be lost. As a solution, a modular environment and architecture facilitates the modification and even the replacement of subsystems and technologies. Each module (subsystem) can be used independently or as a part of the whole BSCS, and can follow its own development cycle. This includes the instrument pipelines, that can run connected or disconnected from the main core BSCS. However, this modularity is only achieved when certain decisions and rules are followed when designing and implementing the systems. The reuse of software from other projects is also part of the selected approach. Reusing software is a standard technique for fulfilling requirements using proven tools, and reducing cost and resources; but increasing the heterogeneity. The modularity isolates technologies and allows future replacements or migrations. This paper shows how the standard three tier architecture components conforming the whole BSCS can be implemented based on a generic infrastructure where every subsystem follows a modular pluggable approach. This is achieved with a design based on the data flowing through a bus formed by the BACS and a set of subsystems repositories. For the actual implementation, an incremental and iterative development allows the users to provide feedback in the critical areas through early and frequent access to the system. A common-sense design oriented approach is being followed, where no sophisticated requirements are pursued, and no complex technologies are part of the baseline of the implementation. An agile-waterfall (pump-waterfall) methodology is taken, where bottom activities inject data not only in the detailed implementation but also in the top-level design and requirements definition. The JIRA tool and a novel technique for tracking the manpower and work packages is also used.

Mode of presentation: poster

Applicable ADASS XXIV theme category: Data Analysis / Pipelines