A Visualization and User Interface Framework for Heterogeneous Distributed Environments

Systems that require complex computations are frequently implemented in a distributed manner. Such systems are often split into components where each component is employed to perform a specific type of processing. The components of a system may be implemented in different programming languages because some languages are more suited for expressing and solving certain kinds of problems. The user of the system must have a way to monitor the state of individual components and also to modify their execution parameters through a user interface while the system is running. The distributed execution and programming language diversity represent a problem for the development of graphic user interfaces. In this paper we describe a framework in which a server provides two types of services to the components of a distributed system. First it manages visualization objects provided by individual components and combines and displays those objects in various views. Second, it displays and executes graphic user interface objects defined at runtime by the components and communicates with the components when changes occur in the user interface or in the internal state of the components. The framework was successfully used in a distributed robotic environment.