A UML 2-based hardware-software co-design framework for body sensor network applications

This paper proposes a unified framework for the hardware/software codesign of body sensor network applications that aims to enhance both modularity and reusability. The proposed framework consists of a Unified Modeling Language (UML) 2 profile for TinyOS applications and a corresponding simulator. The UML profile allows for the description of the low-level details of the hardware simulator, thereby providing a higher level of abstraction for application developers to visually design, document and maintain their systems that consist of both hardware and software components. With the aid of a predefined component repository, minimum TinyOS knowledge is needed to construct a body sensor network system. A novel feature of our framework is that we have modeled not only software applications but the simulator platform in UML. A new instance of the simulator can be automatically generated whenever hardware changes are made. Key design issues, such as timing and energy consumption can be tested by simulating the generated software implementation on the automatically customized simulator. The framework ensures a separation of software and hardware development while maintaining a close connection between them. This paper describes the concepts and implementation of the proposed framework, and presents how the framework is used in the development of nesC-TinyOS based body sensor network applications. Two actual case studies are used to show how the proposed framework can quickly and automatically adapt the software implementation to efficiently accommodate hardware changes.