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Advances in robotics have contributed to the prevalence of human-robot collaboration (HRC). Working and interacting with collaborative robots in close proximity can be psychologically stressful. Therefore, it is important to understand the impacts of human-robot interaction (HRI) on mental stress to promote psychological well-being at the workplace. To this end, this study investigated how the HRI presence, complexity, and modality affect psychological stress in humans and discussed possible HRI design criteria during HRC. An experimental setup was implemented in which human operators worked with a collaborative robot on a Lego assembly task, using different interaction paradigms involving pressing buttons, showing hand gestures, and giving verbal commands. The NASA-Task Load Index, as a subjective measure, and the physiological galvanic skin conductance response, as an objective measure, were used to assess the levels of mental stress. The results revealed that the introduction of interactions during HRC helped reduce mental stress and that complex interactions resulted in higher mental stress than simple interactions. Meanwhile, the use of certain interaction modalities, such as verbal commands or hand gestures, led to significantly higher mental stress than pressing buttons, while no significant difference on mental stress was found between showing hand gestures and giving verbal commands.
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This content will become publicly available on March 1, 2026
Human–Robot Collaboration With a Corrective Shared Controlled Robot in a Sanding Task
Objective: Physical and cognitive workloads and performance were studied for a corrective shared control (CSC) human–robot collaborative (HRC) sanding task. Background: Manual sanding is physically demanding. Collaborative robots (cobots) can potentially reduce physical stress, but fully autonomous implementation has been particularly challenging due to skill, task variability, and robot limitations. CSC is an HRC method where the robot operates semiautonomously while the human provides real-time corrections. Methods: Twenty laboratory participants removed paint using an orbital sander, both manually and with a CSC robot. A fully automated robot was also tested. Results: The CSC robot improved subjective discomfort compared to manual sanding in the upper arm by 29.5%, lower arm by 32%, hand by 36.5%, front of the shoulder by 24%, and back of the shoulder by 17.5%. Muscle fatigue measured using EMG, was observed in the medial deltoid and flexor carpi radialis for the manual condition. The composite cognitive workload on the NASA-TLX increased by 14.3% for manual sanding due to high physical demand and effort, while mental demand was 14% greater for the CSC robot. Digital imaging showed that the CSC robot outperformed the automated condition by 7.16% for uniformity, 4.96% for quantity, and 6.06% in total. Conclusions: In this example, we found that human skills and techniques were integral to sanding and can be successfully incorporated into HRC systems. Humans performed the task using the CSC robot with less fatigue and discomfort. Applications: The results can influence implementation of future HRC systems in manufacturing environments.
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- Award ID(s):
- 2152163
- PAR ID:
- 10613643
- Publisher / Repository:
- Sage
- Date Published:
- Journal Name:
- Human Factors: The Journal of the Human Factors and Ergonomics Society
- Volume:
- 67
- Issue:
- 3
- ISSN:
- 0018-7208
- Page Range / eLocation ID:
- 246 to 263
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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