Imagine feeling the texture of a virtual object without any physical touch. This isn’t science fiction but a reality made possible by pseudo-haptics, a technique that uses visual and auditory cues to trick the brain into perceiving sensations that aren’t physically present. A recent study by Nishant Gautam, Somya Sharma, Peter Corcoran, and Kaspar Althoefer has shed new light on how these cues can be combined to create convincing pseudo-haptic experiences on everyday devices like tablets.
The researchers conducted a psychophysical study to quantify how visual and auditory stimuli work together to evoke the sensation of pressure. They used a Unity-based Rollball game where participants guided a virtual ball across three different textured terrains. The participants’ finger forces were captured in real time using a Robotous RFT40 force-torque sensor. Each terrain was paired with a distinct rolling-sound profile, and crevice collisions triggered additional “knocking” bursts to enhance realism.
The study found that average tactile forces increased systematically with the intensity of the cues. For visual-only trials, the forces were 0.40 N, 0.79 N, and 0.88 N for Terrains 1-3, respectively. For audio-only trials, the forces were slightly higher at 0.41 N, 0.81 N, and 0.90 N. Higher audio frequencies and denser visual textures both elicited stronger muscle activation, and combining these cues further reduced the force needed to perceive surface changes. This confirms the principle of multisensory integration, where the brain combines inputs from different senses to create a coherent perception.
The implications of this research are significant. It demonstrates that consumer-grade isometric devices can reliably induce and measure graded pseudo-haptic feedback without the need for specialized actuators. This opens up new possibilities for affordable rehabilitation tools, training simulators, and assistive interfaces. By leveraging the brain’s ability to integrate visual and auditory cues, developers can create more immersive and interactive experiences without the high cost of traditional haptic hardware.
This study not only advances our understanding of pseudo-haptics but also paves the way for innovative applications in various fields. As technology continues to evolve, the integration of visual and auditory cues will likely play a crucial role in enhancing user experiences and making advanced technologies more accessible.
