Virtual reality crowd simulation: effects of agent density on user experience and behaviour

Agent-based crowd simulations are used for modelling building and space usage, allowing designers to explore hypothetical real-world scenarios, including extraordinary events such as evacuations. Existing work which engages virtual reality (VR) as a platform for crowd simulations has been primarily focussed on the validation of simulation models through observation; the use of interactions such as gaze to enhance a sense of immersion; or studies of proxemics. In this work, we extend previous studies of proxemics and examine the effects of varying crowd density on user experience and behaviour. We have created a simulation in which participants walk freely and perform a routine manual task, whilst interacting with agents controlled by a typical social force simulation model. We examine and report the effects of crowd density on both affective state and behaviour. Our results show a significant increase in negative affect with density, measured using a self-report scale. We further show significant differences in some aspects of user behaviours, using video analysis, and discuss how our results relate to VR simulation design for mixed human–agent scenarios

Acquisition and retention of spatial knowledge through virtual reality experiences: Effects of VR setup and locomotion technique

The fidelity level of virtual reality (VR) setups can affect different aspects of virtual experiences, but its effects on knowledge acquisition and retention need clarification. The two studies in this paper focus on spatial knowledge. The first study compared three VR setups, one using a VR headset and two using a tablet, differing in display and interaction fidelity. Since the type of virtual environment (VE), and the locomotion technique employed to explore it, might affect spatial knowledge acquisition, we studied each setup in an indoor and an outdoor VE with two widely used locomotion techniques (teleport and steering). Results showed that setups offering higher display and interaction fidelity can improve acquisition of spatial knowledge in terms of distance estimations (with teleport in the indoor VE, and with steering in the outdoor VE) and object-to-object spatial relations (with steering in the outdoor VE), but not in terms of object locations. This can provide guidance about how to choose the appropriate combination of setup and locomotion technique based on the type of VE and the types of spatial knowledge to acquire. Moreover, sickness and usability results showed that VR headset was more usable than tablet, and suggest using teleport on VR headset and steering on tablet. Therefore, the second study focused on VR headset with teleport and tablet with steering, and extended the assessment of their effects to spatial knowledge retention after two weeks. Results showed that spatial knowledge decreased in both conditions, but the VR headset with teleport led to better acquisition and 2-weeks retention of distance estimations