Effects of change detection automation and interruption on monitor accuracy, situation awareness and workload during monitoring.

Abstract

Dynamic positioning operators supervise an automated system that keeps a ship at a specific position. However, decreased alertness, limited attention, and especially loss of situation awareness (SA), can lead to minor or major incidents. Our research focusses on the effects of a change detection support on situation awareness, monitor performance and workload. We also investigate if it is possible for an operator to leave his monitoring task, and perform a secondary task when support is provided on the monitoring task. We conduct an experiment with 23 students. The experiment consists of a task in a Dynamic Positioning monitoring environment, and the Visual Elevator task as interruptive secondary task. All subjects complete four conditions: Control, Control with support, interruption, and interruption with support. We show that a support only improves performance when subjects are interrupted during the monitoring task and SA levels are low. When already monitoring, subjects experience more attentional demand when support is present. Furthermore, we show that with support provided after an interruption, subjects make the same number of errors as when they are not interrupted. This suggests that operators could perform other tasks in addition to monitoring, without a significant increase in error rate. This was not the case with workload and response time, however, with subjects being significantly slower after the interruption compared to the static monitoring condition due to higher workload. Hence, it would not be wise to let operators perform a secondary task with only a change detection support.