Tech on the Tip of Your Tongue

Touchscreen displays have grown to become one of the most common types of user interfaces available on portable electronic devices. This is not entirely surprising given how intuitive and adaptable touchscreen interfaces can be. But they are not appropriate for every application. If your hands are tied up with other work, there is no convenient way to interact with this type of interface. Voice control of devices has also become quite common in recent years, but it does not offer the same type of precision and speed one can achieve with a touchscreen display, so it is not always a good alternative.

We have all heard people quip that they cannot control their tongue if they have a tendency to say things that should not be said in polite conversation. But metaphors aside, people actually have excellent control over the muscles of the tongue. In many ways it is like another finger. A team led by researchers at the National University of Singapore took advantage of that fact in building a new type of user interface that is controlled by the tongue. Their device takes the form of a mouthguard, and by sliding one’s tongue around on an array of sensors, the wearer can wirelessly control all sorts of electronic devices with both speed and precision.

Now that's a mouthful

The mouthguard, which covers the lower teeth, has a sensing pad that is made of a silicone and carbon nanotube composite material. The tongue can move across the biocompatible sensing pad in much the same way that a finger slides along a traditional touchscreen. And tapping actions can also be reproduced by biting the pad with one’s upper teeth. A flexible circuit board contains the components needed for processing the sensor data and transmitting it to external devices. To enable the system to recognize complex patterns of interaction, the data is analyzed by a recurrent neural network.

The researchers envision the mouthguard being used by professionals like surgeons and dentists that need to operate computer equipment while their hands are occupied. Given the accuracy and sensitivity of the device, it could also be used by those with certain physical disabilities to help them do everything from typing to gaming.

Since the mouthguard is made of inexpensive components and is light and unobtrusive, it could also eventually find applications in athletic training, speech therapy, biometric identification, and beyond. Perhaps it will even find more mainstream uses among technophiles that are looking for interesting new ways to interact with their digital devices.