Master Thesis - Past Projects - Abstract

Model based development of an airbag software

ID: LiTH-IDA-Ex-04/025-SE

Model-based development is an approach to software development where a model of the software is built in a software tool and then used as the starting point for all other activities. In this report we look at two different modeling technologies, UML with Rhapsody in C and synchronous data-flow with Scade. The work presented was done at Autoliv Electronics AB and the models are based on one of their current airbag systems. Rhapsody in C was used to build a UML model of simplified airbag software. The model includes a structural model with class and object diagrams and a behavioral model with statecharts. C-code was then generated from the model and the software was tested on a PC and on a target micro controller, the TX19A from Toshiba. Scade was used to show how to make a model of the algorithms that detect if a vehicle is in a crash. Formal verification with the Prover plug-in was investigated and a property of the Scade-model was formally verified. Source code was also generated from the Scade model. The Rhapsody model showed great promise when it comes to faster development and less errors. The size of the generated code was the big drawback. Scade has great benefits when modeling control functions or algorithms. The possibility of formal verification can be of great help in the development.

Keywords: Model-based development, UML, Rhapsody, Synchronous data flow, Scade

Author(s): Andreas Eriksson

Contact: Simin Nadjm-Tehrani