The virtual haptics is a crucial aspect of immersive virtual reality, extending the traditional experiences of sight and hearing. The vibration can provide direct normal vibration and friction reduction, making it a promising method to realize virtual haptics. However, the optimum perceptual threshold of skin for vibration is 100 Hz to 500 Hz, resulting in a too low vibrotactile resolution. The conflict between the low perceptual frequency and high resolution still remains challenges. In this paper, a low-frequency envelope wave methodology is proposed to realize the localized vibrotactile feedback. The high-frequency components are modulated into a low-frequency envelope waveform, which provides low-frequency perception and high resolution at the same time. Due to hardware limitations, the modes must be truncated and minimized as much as possible. This requirement conflicts with achieving localized vibration at arbitrary points and further implementing complex vibration patterns. Therefore, a modal optimization algorithm is proposed to solve the inverse problem. The modal participation coefficients is obtained, basing on the evaluation index that ensures the frequency of the envelope wave and the vibration pattern quality. The localized vibration patterns including multiple points, points of proportional amplitude, bar and circle are achieved with a resolution of 3 cm and a perception frequency of about 200 Hz. This method is expected to be applied to virtual reality, blind assistance, and other potential applications to enhance tactile interaction experiences.

中文翻译：

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一种使用高分辨率和低感知频率包络调制的图案化振动触觉方法


虚拟触觉是沉浸式虚拟现实的一个重要方面，扩展了传统的视觉和听觉体验。振动可以提供直接的法向振动和摩擦减少，使其成为实现虚拟触觉的有前途的方法。然而，皮肤对振动的最佳感知阈值是 100 Hz 至 500 Hz，导致振动触觉分辨率过低。低感知频率和高分辨率之间的冲突仍然是挑战。本文提出了一种低频包络波方法来实现局部振动触觉反馈。高频分量被调制为低频包络波形，同时提供低频感知和高分辨率。由于硬件限制，必须尽可能地截断和最小化模式。这一要求与实现任意点的局部振动以及进一步实现复杂的振动模式相冲突。因此，提出了一种模态优化算法来求解反问题。根据保证包络波频率和振型质量的评价指标，得到模态参与系数。局部振动模式包括多点、比例振幅点、条形和圆形，分辨率为 3 cm，感知频率约为 200 Hz。该方法有望应用于虚拟现实、盲人辅助和其他潜在应用，以增强触觉交互体验。