Ungrounded Vari-Dimensional Tactile Fingertip Feedback for Virtual Object Interaction

Compared to grounded force feedback, providing tactile feedback via a wearable device can free the user and broaden the potential applications of simulated physical interactions. However, neither the limitations nor the full potential of tactile-only feedback have been precisely examined. Here we investigate how the dimensionality of cutaneous fingertip feedback affects user movements and virtual object recognition. We combine a recently invented 6-DOF fingertip device with motion tracking, a head-mounted display, and novel contact-rendering algorithms to enable a user to tactilely explore immersive virtual environments. We evaluate rudimentary 1-DOF, moderate 3-DOF, and complex 6-DOF tactile feedback during shape discrimination and mass discrimination, also comparing to interactions with real objects. Results from 20 naive study participants show that higher-dimensional tactile feedback may indeed allow completion of a wider range of virtual tasks, but that feedback dimensionality surprisingly does not greatly affect the exploratory techniques employed by the user.