Task Analysis/Workload (TAWL): A Methodology for Predicting Operator Workload

Abstract

The Task Analysis/Workload (TAWL) methodology was developed to predict operator workload using the information from a task analysis of the system. In addition, the TAWL Operator Simulation System (TOSS) was developed to perform all the data base management and model execution functions needed to use the methodology. A TAWL workload prediction model is developed in three stages: task/workload analysis, model construction, and model execution. The methodology assumes that demand on human attention (workload) can be approximated by modeling the separate cognitive, psychomotor, and sensory requirements of all tasks being performed by the operator. The model produces half-second time lines annotated by task names and workload estimates. The output of the models can be graphed or read by statistical software for further evaluation. TAWL models are useful to system designers as aids in task allocation between crewmembers, machine and crewmembers, and workload components, as well as across time. In addition, the information generated by the models can be used to evaluate the system's manning and training requirements. Currently, the Army is sponsoring the development of TAWL workload prediction models for modified versions of the AH-64A (Apache), CH-47 (Chinook), and UH-60A (Black Hawk) aircraft.

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