Human supervisory control is a complex system phenomenon with high levels of uncertainty, time-pressure, and a dynamically-changing environment. Discrete event simulation (DES), which models a system as a chronological sequence of events representing changes

Discrete event simulations for futuristic unmanned vehicle (UV) systems enable a cost and time effective methodology for evaluating various autonomy and humanautomation design parameters. Operator mental workload is an important factor to consider in such models. We present that the effects of operator workload on system performance can be modeled in such a simulation environment through a quantitative relation between operator attention and utilization, i.e., operator busy time used as a surrogate real-time workload measure. In order to validate our model, a heterogeneous UV simulation experiment was conducted with 74 participants. Performancebased measures of attention switching delays were incorporated in the discrete event simulation model via UV wait times due to operator attention inefficiencies (WTAI). Experimental results showed that WTAI is significantly associated with operator utilization (UT), such that high UT levels correspond to higher wait times. The inclusion of this empirical UT-WTAI relation in the discrete event simulation model of multiple UV supervisory control resulted in more accurate replications of data, as well as more accurate predictions for alternative UV team structures. These results have implications for the design of future humanUV systems, as well as more general multiple task supervisory control models.