Human-Robot Collaboration Levels in Construction: Focusing on Individuals' Cognitive Workload

Small collaborative ground robots that are efficiently capable of accomplishing a variety of tasks have become more ubiquitous on jobsites. With the advancement in technology and automation, it is expected that close collaborations between humans and such robots will drastically increase in the future. However, there is a need to understand how humans working with robots at different interaction levels may result in different human perceptions and cognitive workloads. In this study, a between-subject experiment was created to explore humans' perception towards robots by measuring their cognitive workload at three different human-robot collaboration levels of coexistence, cooperation, and collaboration when accomplishing a real-world bricklaying construction task. Results showed that collaborating with small ground robots may lead to lower physical demand compared to cooperating or simply coexisting with it. However, mental demand, temporal demand, performance, effort, and frustration did not significantly differ between the three collaboration levels. The outcomes of this study provide a better understanding of the safest and most efficient human-robot collaboration practices on jobsites.