View Types and Visual Communication Cues for Remote Collaboration

Over the last several years, remote collaboration has been getting more attention in the research community because of the COVID-19 pandemic. In previous studies, researchers have investigated the effect of adding visual communication cues or shared views in collaboration, but there has not been any previous study exploring the influence between them. In this paper, we investigate the influence of view types on the use of visual communication cues. We compared the use of the three visual cues (hand gesture, a pointer with hand gesture, and sketches with hand gesture) across two view types (dependent and independent views), respectively. We conducted a user study, and the results showed that hand gesture and sketches with the hand gesture cueswerewell matchedwith the dependent viewcondition, and using a pointer with the hand gesture cue was suited to the independent view condition. With the dependent view, the hand gesture and sketch cues required less mental effort for collaborative communication, had better usability, provided better message understanding, and increased feeling of co-presence compared to the independent view. Since the dependent view supported the same viewpoint between the remote expert and a local worker, the local worker could easily understand the remote expert's hand gestures. In contrast, in the independent view case, when they had different viewpoints, it was not easy for the local worker to understand the remote expert's hand gestures. The sketch cue had a benefit of showing the final position and orientation of the manipulating objects with the dependent view, but this benefit was less obvious in the independent view case (which provided a further view compared to the dependent view) because precise drawing in the sketches was difficult from a distance. On the contrary, a pointer with the hand gesture cue required less mental effort to collaborate, had better usability, provided better message understanding, and an increased feeling of co-presence in the independent view condition than in the dependent view condition. The pointer cue could be used instead of a hand gesture in the independent view condition because the pointer could still show precise pointing information regardless of the view type.