Perceiving material properties such as elasticity, flexibility, and torsion is inherently bimanual, as we rely on the relative motion of our hands to form a unified sense of materiality. Yet, most vibrotactile material rendering approaches are limited to a single hand or finger. While prior work has explored bimanual haptic interfaces, most depend on specialized hardware for specific interactions. In this paper, we demonstrate design strategies to support bimanual material exploration through motion-coupled vibrotactile feedback. Our technique introduces variable crosstalk between the controllers' vibration to evoke connectedness, making two unconnected devices feel as though they manipulate a single object. The technique generalizes motion-coupled feedback approaches beyond previous single-point explorations. Through two user studies, we show that this approach (1) significantly enhances perceived connectedness and (2) conveys distinct material qualities such as elasticity and torsion. Finally, we present \textit{Dvihastīya}, an authoring tool for designing connected bimanual experiences in virtual reality.
ACM CHI Conference on Human Factors in Computing Systems