Worker Utilization and Workload in Human-Robot Workplaces

The development of collaborative robots (CRs) has helped to establish collaboration between humans and robots. Allowing humans to work in close proximity to the robot, or even directly with it, raises questions about human safety and well-being, in addition to the many benefits human-robot collaboration (HRC) brings. In this paper, the workers’ workload in HRC is considered from the perspective of worker utilization. To study the workers’ workload three different scenarios were designed (low, high and moderate worker utilization). Each scenario involved the same collaborative operation, but with different CR motion parameters to achieve the desired worker utilization level. Since human capabilities vary from person to person, the CR motion parameters were customized to each individual. The NASA-TLX questionnaire was used to assess the perceived workload. The results indicate a significant influence of worker utilization level on their workload and efficiency. The perceived workers workload decreases in conjunction with utilization levels, 52.5% at high utilization, 28.5% at moderate utilization, and 14.7% at low utilization. In terms of worker efficiency, it is vice-versa, as shorter assembly times of workers were achieved at higher utilization levels. The findings highlight the necessity of personalized guidelines within collaborative workspaces, as the skills, abilities and personalities of individuals contribute to the well-being and productivity of employees.