Negative effects of network latencies in immersive collaborative virtual environments

The present work aims to investigate the negative effects of network latencies in immersive collaborative virtual environments. A user study was conducted to determine the impact of those delays on the performance of users. Participants of the study played a simple cooperative game designed for two players. The goal of the game was to correctly place bicolored cubes into their specific destinations. Since each player only saw the colors of the cubes of his or her partner, both players had to visually and verbally exchange information to complete the game. Each pair of participants played the game under four different latency conditions. The task performance was measured by the time needed to place one cube successfully. Besides, other subjectively observable variables were investigated. The results of the study show that a high end-to-end delay between two VR stations has an adverse effect on the users’ task performance, the amount of mutual understanding and the perceived workload. For the co-presence metric, i.e., the perceived amount of togetherness inside the virtual environment, no significant correlation to the network delay could be determined.