Effects of Biodynamic Stress on Workload in Human Operators

摘要

The objective of this research was to assess the effect of high intensity noise stress and of sustained acceleration on human operator workload and performance. Workload was measured via three different methodologies. Subjective workload was measured with the Subjective Workload Assessment Technique (SWAT); performance-based measures were derived from single and dual psychomotor task performance; and physiological parameters included heart rate, blood pressure, total eye blinks duration, forearm electromyogram and evoked response EEG, especially the latency and amplitude of the P300 peak. The dual task workload consisted of a primary tracking task and a secondary task of monitoring a modified Radar Homing and Warning display. Two levels of pink noise (90 and 100 dB A-weighted) and two levels of sustained acceleration (2.75 and 3.75 Gz) served as the biodynamic stressors. Nine subjects performed the dual task in the Armstrong Aerospace Medical Research Laboratory human centrifuge. Exposures were 60 seconds long during which time subjects' noninvasive physiological parameters were monitored in either noise or acceleration conditions. The results indicate that biodynamic stressors such as noise and acceleration adversely affect subjective operator workload without affecting objective task performance and that physiological workload measures such as eye blink and blink duration are ineffective in the acceleration environment.