Master of Science in Industrial Engineering (MSIE)


Mechanical Engineering

Document Type



There is a dearth of research on the effect of driving through work zones on physiological and subjective workload of drivers. The objectives of this research were to (a) study the effect of work zones and traffic density on physiological measures of workload, subjective workload and performance variables (b) study the relationship between physiological measures of workload, subjective workload and performance variables. Conventional lane merge (CLM), joint lane merge (JLM) and a road without a work zone (control) were modeled with high and low traffic density by using a full-size driving simulator. 13 female and 17 male students volunteered to participate in this study. Data regarding physiological measures of workload through heart rate variability measures (RMSSD, LF, HF and LF/HF ratio) were collected by using a heart monitoring watch. NASA-TLX was used to measure subjective workload. Variability in steering, braking and speed were used as performance variables. Results showed that the driving scenarios and traffic density did not affect physiological measures of workload. In terms of subjective workload, CLM and JLM did not differ significantly from each other. However, with respect to mental demand, temporal demand, effort and total workload, CLM was significantly more demanding than the control group. Total workload for driving in high traffic density was 27.2% more than that of in low traffic density. No significant differences were observed in brake variability between different scenarios. However, CLM and JLM had significantly higher speed variability than the control group but they were not significantly different from each other. Steer variability and brake variability were higher in high traffic density. In conclusion, results showed that when it comes to using driving simulators, physiological measures of workload show no sensitivity to changes in the work zone but subjective and performance variables are influenced and can be used to compare different work zone configurations.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Ikuma, Laura H