Use of Model-Based Qualitative Icons and Adaptive Windows in Workstations for Supervisory Control Systems

Abstract

Model-based qualitative icons and adaptive window display interfaces may be valuable tools to enhance the effectiveness of operators in real-time data-intensive supervisory control systems. Qualitative icons may be used to integrate low-level quantitative data into high-level qualitative error detection mechanisms. Using windowing technology, multiple data sources that reflect different aspects of system state can be displayed simultaneously on a single screen. Both technologies were combined and implemented to design an operator interface to the Georgia Tech-Multisatellite Operation Control Center (GT-MSOCC). An operator function model for GT-MSOCC was used to derive workstation features, including hardware configuration, the function of qualitative icons for monitoring, fault detection and identification, and the contents and placement of computer windows. The model also determined sets of windows needed by the operator to undertake major operator control functions. An experiment was performed to evaluate the effectiveness of a workstation incorporating model-based qualitative icons and dynamic operator function window sets. Subjects controlled GT-MSOCC via either a conventional operator interface or the model-based interface. Eleven measures that reflected operator performance were analyzed. Subjects using the model-based workstation operated the system significantly better on nine of these measures. On all measures, performance with the model-based workstation was uniformly better on average and had less variability than performance with the conventional workstation.