Modulation of the frictional force of a fingertip sliding over a surface-haptic device can produce compelling sensations of texture and relief. The virtual sensation is particularly apparent and feel as fixed in space if the stimulus is rigorously correlated with the displacement of the finger. While frictional textures tactually resemble their real counterparts, some exploratory conditions under which the sharpness of the texture declines exist. We postulate that this decline in sharpness is caused by the perceptual limitation of the attempt to interpret the variation in friction as an out-of-plane sinusoidal topography. To investigate these questions, we measured the detection thresholds of sinusoidal friction-modulated gratings for a wide range of spatial periods explored at two different speeds. We compared the results with the detection thresholds, reported in the literature, of real gratings and vibrotactile stimuli. We found that the detection of spatial friction-modulated textures does not follow the same trend as that of real textures but is more similar to the vibrotactile rendering, which is strongly influenced by the exploratory speed. This article provides a better understanding of the perception of friction-modulated textures and provides insight into how to design impactful stimuli on surface-haptic devices.

中文翻译：

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摩擦调制纹理的检测受到振动触觉灵敏度的限制

指尖在表面触觉设备上滑动的摩擦力的调制可以产生引人注目的纹理和浮雕感觉。如果刺激与手指的位移密切相关，则虚拟感觉特别明显并且感觉在空间中是固定的。虽然摩擦纹理在触觉上类似于它们的真实对应物，但存在纹理锐度下降的一些探索性条件。我们假设这种锐度下降是由于试图将摩擦变化解释为平面外正弦地形的感知限制引起的。为了研究这些问题，我们测量了正弦摩擦调制光栅在以两种不同速度探索的各种空间周期内的检测阈值。我们将结果与文献中报道的真实光栅和振动触觉刺激的检测阈值进行了比较。我们发现空间摩擦调制纹理的检测与真实纹理的检测趋势不同，但更类似于振动触觉渲染，后者受探索速度的影响很大。本文提供了对摩擦调制纹理感知的更好理解，并提供了有关如何在表面触觉设备上设计有影响力的刺激的见解。