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Resonant frequency skin stretch uses cyclic lateral skin stretches matching the skin’s resonant frequency to create highly noticeable stimuli, signifying a new approach for wearable haptic stimulation. Four experiments were performed to explore biomechanical and perceptual aspects of resonant frequency skin stretch. In the first experiment, effective skin resonant frequencies were quantified at the forearm, shank, and foot. In the second experiment, perceived haptic stimuli were characterized for skin stretch actuations across a spectrum of frequencies. In the third experiment, perceived haptic stimuli were characterized for different actuator masses. In the fourth experiment, haptic classification ability was determined as subjects differentiated haptic stimulation cues while sitting, walking, and jogging. Results showed that subjects perceived stimulations at, above, and below the skin’s resonant frequency differently: stimulations lower than the skin resonant frequency felt like distinct impacts, stimulations at the skin resonant frequency felt like cyclic skin stretches, and stimulations higher than the skin resonant frequency felt like standard vibrations. Subjects successfully classified stimulations while sitting, walking, and jogging, perceived haptic stimuli was affected by actuator mass, and classification accuracy decreased with increasing speed, especially for stimulations at the shank. This work could facilitate more widespread use of wearable skin stretch. Potential applications include gaming, medical simulation, and surgical augmentation, and for training to reduce injury risk or improve sports performance.
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Realism of Tactile Texture Playback: A Combination of Stretch and Vibration
Not AvailableThis study investigates the effects of two stimulation modalities (stretch and vibration) on natural touch sensation on the volar forearm. The skin-textile interaction was implemented by scanning three natural textures across the left forearm. The resulting in-plane displacements across the skin were recorded by the digital image correlation technique to capture the information imparted by the textures. The texture recordings were used to create three playback modes (stretch, vibration, and both), which were reproduced on the right forearm. Two psychophysical experiments compared the physical texture scans to rendered texture playbacks. The first experiment used a matching task and found that to maximize perceptual realism, i.e., similarity to a physical reference, subjects preferred the rendered texture to have a playback intensity of approximately 1X – 2X higher on DC components (stretch), and 1X – 3.5X higher on AC components (vibration), varying across textures. The second experiment elicited similarity ratings between the texture scans and playbacks and showed that a combination of both stretch and vibration was required to create differentiated texture sensations. However, the intensity amplification and use of both stretch and vibration were still insufficient to create fully realistic texture sensations. We conclude that mechanisms beyond singlesite uniaxial stimuli are needed to reproduce realistic textural sensations.
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- Award ID(s):
- 2106191
- PAR ID:
- 10652002
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Transactions on Haptics
- Volume:
- 17
- Issue:
- 3
- ISSN:
- 1939-1412
- Page Range / eLocation ID:
- 441 to 450
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/TOH.2024.3355982
