Managing workload in human–robot interaction: A review of empirical studies

Working with artificial agents is a challenging endeavor, often imposing high levels of workload on human operators who work within these socio-technical systems. We seek to understand these workload demands through examining the literature in major content areas of human–robot interaction. As research on HRI continues to explore a host of issues with operator workload, there is a need to synthesize the extant literature to determine its current state and to guide future research. Within HRI socio-technical systems, we reviewed the empirical literature on operator information processing and action execution. Using multiple resource theory (MRT; Wickens, 2002) as a guiding framework, we organized this review by the operator perceptual and responding demands which are routinely manipulated in HRI studies. We also reviewed the utility of different interventions for reducing the strain on the perceptual system (e.g., multimodal displays) and responses (e.g., automation). Our synthesis of the literature demonstrates that much is known about how to decrease operator workload, but there are specific gaps in knowledge due to study operations and methodology. This work furthers our understanding of workload in complex environments such as those found when working with robots. Principles and propositions are provided for those interested in decreasing operator workload in applied settings and also for future research.