In virtual/augmented/mixed reality (VR/AR/MR) applications, rendering soft virtual objects using a hand-held haptic device is challenging due to the anatomical restrictions of the hand and the ungrounded nature of the design, which affect the selection of actuators and sensors and hence limit the resolution and range of forces displayed by the device. We developed a cable-driven haptic device for rendering the net forces involved in grasping and squeezing 3D virtual compliant (soft) objects being held between the index finger and thumb only. Using the proposed device, we investigate the perception of soft objects in virtual environments. We show that the range of object stiffness that can be effectively conveyed to a user in virtual environments (VEs) can be significantly expanded by controlling the relationship between the visual and haptic cues. We propose that a single variable, named Apparent Stiffness Difference, can predict the pattern of human stiffness perception under manipulated conflict, which can be used for rendering a range of soft objects in VEs larger than what is achievable by a haptic device alone due to its physical limits.

中文翻译：

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视觉和触觉提示冲突下虚拟环境中软物体的感知。

在虚拟/增强/混合现实（VR/AR/MR）应用中，由于手的解剖学限制和设计的不接地性，使用手持式触觉设备渲染软虚拟对象具有挑战性，这会影响选择执行器和传感器，因此限制了设备显示的力的分辨率和范围。我们开发了一种电缆驱动的触觉设备，用于渲染仅在食指和拇指之间抓握和挤压 3D 虚拟顺从（软）物体所涉及的净力。使用所提出的设备，我们研究了虚拟环境中软物体的感知。我们表明，通过控制视觉和触觉提示之间的关系，可以显着扩展虚拟环境（VE）中可以有效传达给用户的物体刚度范围。我们提出，一个名为表观刚度差异的变量可以预测操纵冲突下人体刚度感知的模式，该变量可用于渲染 VE 中的一系列软物体，其大小比单独触觉设备所能实现的要大，因为它的物理限制。