A lollipop interface for simulating taste in virtual environments

A team of biomedical engineers and virtual reality researchers has developed a lollipop interface to simulate taste in a virtual environment. They have published their research in Proceedings of the National Academy of Sciences.

Over the past several years, engineers have improved the virtual, or augmented reality, experience—users often forget they exist in the real world as they engage in voyages, games and other adventures. Yet some aspects of the virtual world are still missing, most notably, the senses of smell and taste. In this new effort, the research team sought to build a device that would allow a virtual environment explorer to taste items in the virtual world they are exploring.

The device is meant to resemble an ordinary lollipop. When a virtual explorer licks the mechanical lollipop, it is supposed to feel and taste like they are licking a real one. The researchers embedded pouches in the device that hold small quantities of agarose gel. A small amount of voltage (2 V) activates chemicals in the gel, forcing it to the surface of the lollipop. When the gel mixes with the saliva in the user's mouth, it produces flavor.

The researchers added nine pouches to the lollipop with gels containing salt, sugar, cherry, citric acid, green tea, passion fruit, grapefruit, durian and milk. The quantity delivered depends on the voltage applied. Various flavors can be generated by varying the amounts of the different ingredients.

Testing of the device showed it worked nearly as well as expected. The team suggests their lollipop device could be useful under three main scenarios—as gustation tests by doctors, online shopping experiences in grocery stores and specialized environments where children can try out different flavors, perhaps as part of a virtual reality game.

The researchers acknowledge that their system, like other attempts to add taste to virtual reality environments, is limited by the amount of get the lollipop can contain—typically about an hour's worth of licking. The team plans to seek ways to increase the number of flavors and make the lollipop last much longer before refilling.