Högskolan i Skövde

The present study investigates how roughness perception can be modulated through vibrotactile, visual, and auditory cues in augmented reality using a 3D printed vibrotactile feedback bracelet. Participants compared virtual textures differing in roughness parameters, including vibration frequency and amplitude, visual grain size, and sound recordings from real sandpapers. Results showed strong linear relationships between parameter levels and perceived roughness across modalities, particularly for frequency and visual conditions. Audio also modulated perception, albeit less consistently. When audio or haptic feedback was addedto visual condition, perceived roughness slightly decreased, suggesting the added input acted as perceptual noise when it lacked task-relevant information. Furthermore, interindividual differences emerged: participants who rated haptics as the easiest modality for roughness discrimination were more sensitive to haptic changes, while those who rated vision showed less sensitivity to haptic parameters. These findings demonstrate that roughness perception in augmented reality can be systematically manipulated across all three modalities, and that individual sensory strategies may shape how users interpret multimodal feedback. This has important implications for the design of more realistic and immersive haptic experiences in augmented and virtual reality, enabling better environments for virtual training and education.