Virtual Reality (VR) has recently gained traction with many new and ever more affordable devices being released. The increase in popularity of this paradigm of interaction has given birth to new applications and has attracted casual consumers to experience VR. Providing a self-embodied representation (avatar) of users' full bodies inside shared virtual spaces can improve the VR experience and make it more engaging to both new and experienced users . This is especially important in fully immersive systems, where the equipment completely occludes the real world making self awareness problematic. Indeed, the feeling of presence of the user is highly influenced by their virtual representations, even though small flaws could lead to uncanny valley side-effects. Following previous research, we would like to assess whether using a third-person perspective could also benefit the VR experience, via an improved spatial awareness of the user's virtual surroundings. In this paper we investigate realism and perspective of self-embodied representation in VR setups in natural tasks, such as walking and avoiding obstacles. We compare both First and Third-Person perspectives with three different levels of realism in avatar representation. These range from a stylized abstract avatar, to a "realistic" mesh-based humanoid representation and a point-cloud rendering. The latter uses data captured via depth-sensors and mapped into a virtual self inside the Virtual Environment. We present a throughout evaluation and comparison of these different representations, describing a series of guidelines for self-embodied VR applications. The effects of the uncanny valley are also discussed in the context of navigation and reflex-based tasks.

翻译：虚拟现实（VR）近年来随着众多新型且价格日益亲民的设备发布而获得广泛关注。这种交互范式的普及催生了新的应用场景，并吸引了普通消费者体验VR。在共享虚拟空间中为用户提供全身的自我具身表征（虚拟替身）能够提升VR体验，使新老用户都更具沉浸感。这在完全沉浸式系统中尤为重要，因为此类设备完全遮蔽现实世界，导致用户难以感知自身存在。事实上，用户的临场感高度受其虚拟表征影响，即使微小缺陷也可能引发恐怖谷效应。基于先前研究，我们拟评估第三人称视角是否能通过增强用户对虚拟环境的空间感知来优化VR体验。本文研究了自然任务（如行走和避障）中VR设备下自我具身表征的真实感与视角选择。我们比较了第一人称与第三人称视角，并测试了三种不同真实度等级的虚拟替身表征：从风格化抽象替身，到基于网格的"写实"人形表征，再到点云渲染——后者通过深度传感器捕获数据并将其映射为虚拟环境中的虚拟自我。本文对这些不同表征进行了全面评估与比较，总结出一系列针对自我具身VR应用的设计指南，并探讨了恐怖谷效应在导航与反射性任务中的影响。