Enhancing Ultrasound Haptics with Parametric Audio Effects

Ultrasound haptic devices can create parametric audio as well as contactless haptic feedback. We investigate if multimodal output from these devices can influence the perception of haptic feedback. We used a magnitude estimation experiment to evaluate perceived roughness of an ultrasound haptic pattern. We found that white noise audio from the haptics device increased perceived roughness and pure tones did not, and that lower rendering frequencies may increase perceived roughness. Our results show that multimodal output has the potential to expand the range of sensations that can be presented by an ultrasound haptic device, paving the way to richer mid-air haptic interfaces.