Mental workload assessments of aerial photography missions performed by novice unmanned aerial vehicle operators

BACKGROUND

Mental workload is one of the important variables in understanding human performance in drone operation.

OBJECTIVE

To test the effects of gender, age group, flight route, and altitude on the flight performance and mental workload of the novice drone operators.

METHODS

Ten male and 10 female participants without prior drone operating experience joined. They were split into two age groups. After attending a training, the participants operated a drone to perform photo taking missions under flight route and altitude conditions. The weighted NASA task-load-index (TLX), modified Cooper-Harper (MCH) scale, heart rate, and interbeat interval were measured to assess the mental workload of the participants. Flight time to complete the mission was adopted to indicate flight performance.

RESULTS

The effect of age group was significant (p <  0.05) on flight time, weighted TLX score, and MCH score. Flight route and altitude were not significant on the two subjective ratings and two cardiac measures.

CONCLUSION

The flight performance of younger participants was significantly better than that of their older counterpart. The effects of both the flight route and altitude on the perceived mental workload of the drone operators were insignificant. Both the weighted NASA TLX and MCH scales were appropriate in measuring the mental workload of the novice drone operators.

Risky scenario identification in a risk perception scale for construction workers in Thailand

INTRODUCTION

Construction sites exhibit unique hazardous characteristics. Hence, investigating the causes of fatal and nonfatal accidents is extremely important to promote safety on construction sites. Literature shows a risk perception (RP) scale for construction workers; to expand the existing research, this study aims to identify risky scenarios for assessing the RP of Thai construction workers, with the goal of reducing workplace incidents.

METHOD

The scale development process consists of four phases. Item development was also performed, followed by factor analysis. Reliability and validity assessments were finalized in the process. A survey of 500 construction workers in Thailand was conducted to investigate risky scenarios. Through the process, a total of 17 items remained in the final RP scale, and the reliability and validity of these items were confirmed.

RESULTS

The RP scale was affirmed to have four dimensions (probability, severity, worry, and unsafe). These dimensions of workers' RP were negatively correlated with the workers' risk-taking behaviors. This study further showed that participants with a high level of affective RP were more likely to have a high level of cognitive RP. Hence, those with a high level of RP tended to be involved in fewer risk-taking behaviors. Practical Applications: The final version of the scale was reliable and valid in determining the RP and risk-taking behaviors of construction workers in Thailand.