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VOILA: A System for Looking at Processes



Sanford P. Ressler, Steve Clark


The ability to visualize data is becoming an increasingly important research field in its own right. How do scientists present, view, and communicate the information contained in data, systems or programs in meaningful ways? This paper presents one approach to the problem of visualization in the context of illustrating and observing a control system. Specifically, the application domain is a real-time control system (RCS) developed at NIST. This system allows a control system to be specified as a hierarchy of finite state machines. Although it was developed primarily for the control of factory floor applications, the RCS has been applied to many other types of systems as well, including multiple autonomous underwater vehicles, the strategic defense initiative, and telerobotic arm control. Integration into the existing control systems development environment was a key goal of the visualization project.
NIST Interagency/Internal Report (NISTIR) - 4196
Report Number


Ressler, S. and Clark, S. (1989), VOILA: A System for Looking at Processes, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD (Accessed June 22, 2024)


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Created December 31, 1988, Updated October 12, 2021