Encountered-Type Haptic Displays (ETHDs) provide haptic feedback by positioning a tangible surface for the user to encounter. This permits users to freely eliciting haptic feedback with a surface during a virtual simulation. ETHDs differ from most of current haptic devices which rely on an actuator always in contact with the user. This article intends to describe and analyze the different research efforts carried out in this field. In addition, this article analyzes ETHD literature concerning definitions, history, hardware, haptic perception processes involved, interactions and applications. The paper proposes a formal definition of ETHDs, a taxonomy for classifying hardware types, and an analysis of haptic feedback used in literature. Taken together the overview of this survey intends to encourage future work in the ETHD field.

中文翻译：

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“按需触觉”：对接触式触觉显示器的调查

遭遇型触觉显示器 (ETHD) 通过为用户放置有形表面来提供触觉反馈。这允许用户在虚拟模拟期间自由地用表面引发触觉反馈。EHD 与大多数当前的触觉设备不同，后者依赖于始终与用户接触的执行器。本文旨在描述和分析在该领域开展的不同研究工作。此外，本文还分析了涉及定义、历史、硬件、触觉感知过程、交互和应用的 EHD 文献。该论文提出了 EHD 的正式定义、用于对硬件类型进行分类的分类法以及对文献中使用的触觉反馈的分析。综上所述，本次调查的概述旨在鼓励未来在 EHD 领域的工作。