Manual assembly and Human–Robot Collaboration in repetitive assembly processes: a structured comparison based on human-centered performances

Abstract

Human–Robot Collaboration (HRC) represents an innovative solution able to enhance quality and adaptability of production processes. However, to fully exploit the benefits of HRC, human factors must be also taken into account. A novel experimental setting involving a repetitive assembly process is presented to investigate the effects of prolonged HRC on user experience and performance. Each participant was involved in two 4-h shifts: a manual assembly setting and a HRC one. The response variables collected in the study included self-reported affective state, perceived body discomfort, perceived workload, physiological signals for stress (i.e., heart rate variability and electrodermal activity), process and product defectiveness. Experimental results showed less upper limb exertion in the HRC setting, emphasizing the contribution of cobots in improving physical ergonomics in repetitive processes. Furthermore, results showed reduced mental effort, stress, and fewer process defects in the HRC setting, highlighting how collaborative robotics can improve process quality by supporting operators from a cognitive point of view in repetitive processes.