Pedro Ermida Monteiro

Abstract

Abstract
Although selection menus are widely used for interaction, their use on 3D virtual reality applications needs to be objectively assessed. The focus of this study is to evaluate a traditional panel and a radial menu in two distinct virtual environment placements (i.e. fixed on the wall and following the users' hands). Fifty-one participants used two different menus of the four possible combinations. To evaluate the menus' effectiveness and efficiency, we measured usability (System Usability Scale Questionnaire), user satisfaction (After-Scenario Questionnaire), time to finish the tasks (in seconds) and the number of unnecessary steps (errors) performed by the users. Overall results showed a clear preference for the traditional panel menu type and the fixed wall placement of the menu. We conclude that all menu types perform well, despite different user preferences, and that fixing the menu to the wall gives users a better overview of both the menu and the virtual environment, improving their ability to perceive their actions on the menu.

Abstract
Virtual Reality (VR) technologies have evolved to the point where it is being used in various areas (entertainment, medicine, education, etc.). One of the metrics that allow the evaluation of the virtual experience is Presence. In this work, we conduct an exploratory study that studies which factors of VR games correlate to presence. Various components of games are also shared between other VR applications allowing the results to be applicable not only in VR games. A study with 78 participants divided into 5 groups was conducted where each group played a different VR game. Presence and Game Experience were evaluated. The results indicated multiple positive correlations between subscales of Presence and Game Experience. © 2019 IEEE.

Abstract
Innovations in virtual reality have boosted their use for business purposes and personal consumption. The main objective of this technology is to transport the user to virtual environments. The use of avatars to replace the user's body in these environments increases the levels of presence and embodiment of the user. Through the inverse kinematics it is possible to animate the avatars according to the data obtained in sensors scattered around the user's body, replicating the movements in a avatar. These sensors can vary in number offering different levels of fidelity in the tracking of the human body. In this paper, we study the impact of the number of sensors used in the presence of the user and in the embodiment of the avatar, using three, five and six tracking points. The results show that there is no statistically significant differences in presence nor in any of its sub-scale, however one can observe a positive trend in the 6-points conditions. As for embodiment, the results show that there is statistically signifficant differences in some of presence sub-scales, namelly tactile sensation, response and in the embodiment as a whole. © 2019 IEEE.

Abstract