Virtual Environment Assessment for Tasks Based on Sense of Embodiment

Abstract

The quality of a virtual environment for a specified task based on the concept of sense of embodiment (SoE) was assessed in this study. The quality of virtual reality (VR) is evaluated based on the VR system or apparatus’s performance; however, we focused on VR users executing tasks in virtual environments and tried to assess the virtual environment for the tasks. We focused on the user’s sense of agency (SoA) and sense of self-location (SoSL), which were considered as components of the SoE. The SoA was measured based on the surface electroencephalogram of two body parts and our SoE questionnaire. We analysed the surface electroencephalogram waveforms using signal averaging and determined the observable latent time from the analysed waveforms for estimating the state of SoA. To assess the different virtual environments, we built two virtual environments composed of different versions of SPIDAR-HS as a haptic interface and a common head-mounted display. The experiment was executed in two virtual environments in addition to the reality environment. In the three environments, the participants executed the rod tracking task (RTT) in a similar way, and their EMG and subjective data were measured during the RTT. From the results, we considered the task performance based on the participants’ SoA and SoSL, and the quality of the two virtual environments were compared. Furthermore, the relation between the quality of the virtual environment and the factors related to the characteristics of haptic and visual interfaces was revealed to some extent.