Supporting Reuse in Event B Development: Modularisation Approach

Abstract

Recently, Space Systems Finland has undertaken formal Event B development of a part of on-board software for the BepiColombo space mission. As a result, lack of modularization mechanisms in Event B has been identified as a serious obstacle to scalability. One of the main benifits of modularization is that it allows us to decompose system models into components that can be independently developed. It also helps to manage complexity of models that in the industrial setting are usually very large and difficult to comprehend. On the other hand, modularization enables reuse of formally developed components in the formal product line development. In this paper we propose a conservative extension of Event B formalism to support modularization. We demonstrate how our approach can support reuse in the formal development in the space domain.