Will Operators Work in Close Proximity to Industrial Robots? A Study of Acceptance Using Psychological and Physiological Responses

Industry 4.0 and the introduction of human-robot collaboration offers manufacturing companies the potential for increased productivity and efficiency. However, robots can still be a concern for human operators. The present study aimed to investigate people’s acceptance of working alongside an industrial robot. Participants completed a drilling and measuring task in three experimental conditions: working close to the robot, working at a further distance from the robot and, as a control condition not measuring proximity effects, working without the robot operating. Physiological responses (skin conductance and heart rate) and eye gaze were recorded, along with self-report psychometric measures of trust, attitudes towards the robot, technology readiness, workload, situation awareness, and qualitative opinions relating to satisfaction. Results show little to no change in any of the self-reported psychometric measures between the experimental conditions, indicating that proximity had no effect on participants’ psychological states. However, in both of the experimental conditions examining proximity effects skin conductance levels were higher than in the control condition, indicating that arousal levels are increased by the robot simply being operational regardless of proximity. Results also suggest that participants evaluated their performance as better if they completed their task before the robot finished, which provides some insight into the potential dynamics of future human-robot partnerships and the need for collaborative tasks to be designed with care so that task cycle times suit requirements of both the robot and the operator.