When it comes to virtual reality, the visual technology is quite good and can convince our brains that we’re inside a digital 3D environment. Audio is also decent, thanks to established interaural 3D audio techniques. But current consumer VR setups fail to adequately incorporate our other senses and that failure breaks the immersive illusion. To bring tongues into the mix, researchers from the University of Calgary and University of Maine have developed TactTongue which provides on-demand electrotactile stimulation.
TactTongue creates both physical, tactile sensations and also some measure of taste. Both are the result of electrical pulses through electrodes on a mouth piece worn over the tongue. That matrix of electrodes covers much of the tongue’s surface to add a spatial layer to the equation. The user can, for example, feel a pulse moving from the tip of their tongue to the back-right portion of their tongue. TactTongue can also generate a feeling of taste (salt in particular), thanks to the physiological mechanism by which our tongues perceive saltiness through ion transfer.
It is possible to direct electrical pulses to specific parts of the tongue with the TactTongue hardware, implemented as a shield for Arduino UNO Rev3 boards. That passes current down a flexible ribbon cable to electrode pads embedded in the cable.
The team behind TactTongue developed toolkits for prototyping “haptic experiences” with this technology. Those control the electrodes active at any given time, but also the pulse intensity and waveform patterns. It is possible to tie the haptic experiences to specific software events, both in VR games and software, to offer feedback or direction to users.