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Expert Control System Shell Version 1.0 User



Steve Osella


The Expert Control System Shell (ECSS)is a software program running on a Macintosh computer which permits the rapid prototyping of control system architectures and strategies. The ECSS consists of a user interface development tool, a rule-based expert system, an integrated text editor, a data-logging and playback facility, and a generic external device interface. The user-interface permits the design of graphical controls which are either actuators (push-usa-buttons, toggles, and slider-control, etc.) or displays (LEDs, strip-charts, dials, etc.). The actuators can be manipulated directly by the operator, by the knowledge-base system, or both. A display can be directly linked to an external device, can be set by the expert system, or can be a calculated value from other actuators and/or displays. The rule-based expert system facility permits the creation of concurrently operating control modules which can synchronize their activity using message passing. The expert system is forward-chaining and is driven by operator actions, external events, and/or by messages from other control modules. Control modules can make function calls to external C language routines, which could be, for example, a PID control function. The ECSS permits the logging of all control values and the subsequent play back using a remote control graphical device.
NIST Interagency/Internal Report (NISTIR) - 5601
Report Number


control systems, expert systems, multi-agent systems, real-time systems


Osella, S. (1995), Expert Control System Shell Version 1.0 User, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 28, 2024)


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Created January 1, 1995, Updated November 10, 2018