A central objective of the Model-Driven Development (MDD) approach is to separate the design and architecture from concrete realizations. The developer should be able to design the application at an abstract level and not be confronted with platform specific details of implementation. The conceptual of realizing design the functional requirements is specified in the Platform Independent Model (PIM). It is transformed to one or more PSM (Platform Specific Model) which provide the base for the actual implementation.
The developer focuses on the overall robotic system architecture in terms of communication and modules channels between them in SPICA. The platform independent model is called AAS (Abstract Architecture Specification). The transformation process from the AAS to the finally resulting source code in one programming language or multiple programming languages.
The main AAS modeling entitles are messages, protocols, and modules. Modules represent the architecture building blocks. Messages are structure data exchanged between the modules, while protocols are behavior transmission descriptions.
The AAS is defined using three domains of specific modeling languages: Message Description Language (MDL), Protocol Description Language (PDL), and Data Flow Description Language (DFDL).they are tailored to the different architecture aspects. These three languages are used in order separate clearly the orthogonal concerns of data flow, protocol state transitions, and message structure.
The AAS can be considered as the overall model system which represent the layout of target software architecture. Currently, it is prepared in a text format but now the developers are working on a graphical composer incorporating UML 2.0.
The AASTra (AAS Transformer) is the central part of SPICA. It performs model transformations and integrity checks from the AAS down to the concrete implementation. The AIR (AAS Intermediate Representation) is generated from the AAS model, forms a data pool for the final code transformation step and represent s the PSM. The tree representation of AAS is AIR.
No comments:
Post a Comment