Understanding Stationary and Moving Direct Skin Vibrotactile Stimulation on the Palm

TL;DR

This study systematically investigates how different configurations of vibrotactile actuators on the palm affect perception, localization, and recognition of stationary and moving tactile stimuli, informing design choices for high-resolution tactile displays.

Contribution

It provides empirical data on optimal actuator configurations for stationary and moving tactile sensations on the palm, guiding future tactile display design.

Findings

9 actuator display balances complexity and localization accuracy

3x3 resolution effectively localizes stationary sensations

2x4 resolution maximizes recognition of moving sensations

Abstract

Palm-based tactile displays have the potential to evolve from single motor interfaces (e.g., smartphones) to high-resolution tactile displays (e.g., back-of-device haptic interfaces) enabling richer multi-modal experiences with more information. However, we lack a systematic understanding of vibrotactile perception on the palm and the influence of various factors on the core design decisions of tactile displays (number of actuators, resolution, and intensity). In a first experiment (N=16), we investigated the effect of these factors on the users' ability to localize stationary sensations. In a second experiment (N=20), we explored the influence of resolution on recognition rate for moving tactile sensations.Findings show that for stationary sensations a 9 actuator display offers a good trade-off and a $3\times3$ resolution can be accurately localized. For moving sensations, a $2\times4$ resolution led to the highest recognition accuracy, while $5\times10$ enables higher resolution output with a reasonable accuracy.