Research On Extention Of Function For HLA/RTI Based On Middleware

High Level Architecture (HLA) is the current key and highlighted issue in distributed simulation. In this paper an extension of HLA/RTI based on middleware is studied.Firstly, the definitions and components of HLA/RTI are introduced briefly,including rules, OMT and interface specification. The software development method of HLA/RTI is described particularly from five aspects,composed of architectures,OO, RTI software implementation,federate development and federation development process.In order to extend the function of distributed simulation framework for existing HLA/RTI, in this paper an extension of HLA/RTI based on middleware which can not only encapsulate the standard RTI services but also extend needed ones is proposed. The middleware level provides standard interfaces as well as extended ones for special purposes for users, through which federates communicate each other. The extended HLA/RTI has the advantages of portability, compatibility and transparency. At last a prototype is implemented and tested as well.Entity migration can help to improve the performance of large-scale distributed simulation system. In this paper the advantages and disadvantages that HLA/RTI supports entity migration are studied. Finally, an entity-migration arbitration prototype is proposed in HLA/ERTI.To achieve lnteroperability,reusability and time-space consistency coordinate transformation mechanism should be offered for different simulation applications. The transformation relationships between the ordinary coordinates are introduced in this paper. The synthetic transformation mode implemented can reduce transformations between different coordinates, and cut down the accumulated error in the transformations.