<title>Interactive creation of plant monitors and controls</title>

Abstract

This paper describes an approach for the interactive creation and configuration of plant monitors and controls. It is based on top of three basic services, which were built to solve several often found problems: Fluids for general man machine interaction, IAM, an intelligent measurement and control service and a platform independent real-time operating system for distributed applications. The described solution combines these services to allow an interactive configuration management and the execution of the resulting model. Keywords: graphical user interface, data visualization, plant monitor OVERVIEWIn most systems, the construction of the user interface and its connections to the application program are the most time-intensive parts in the software development. To reduce this time overhead, our institute has introduced several so called services, which are only configured for a special application and not modified in any way. Services are the basic unit of distribution, each service consists of at least one process. The result is a client/server based application, which uses a CORBA based system platform for communication and distribution handling as well as for process scheduling. Services provide re-usable standardized building blocks which can be created, configured, controlled and interconnected in order to construct the application, based on a service-oriented design scheme. 13 Since most automation applications are a mixture of data acquisition, control, data storage and man-machine interaction, this paper describes an approach to combine already existing services to simplify the construction of plant monitors and controls. First, the necessary services are introduced and second, the idea of a graphical configuration is presented. SYSTEM PLATFORMThe system platform offers an unique virtual operating system on top of many standard operating systems. Its most important tasks are the communication handling between the services and the process scheduling. To make the handling of distributed services transparent, a replaceable communication system is one of the basic components of the platform. This modular composition allows the exchange of the transport layer (serial line, Ethernet, . . . ) without any changes in the services. The API is based on CORBA. 17 The Interface Definition Language (IDL) is used for object access specification. 16 Object relations are expressed using CORBA's relationship specification. 15 Pictures 1 shows the structure.