The smart watch that many people use every day, its text input is either by voice, or by typing.
But if when you are in an environment with a lot of background noise, or when you want to keep the information content of people around you secret, the method of voice input text is not not ideal. At the same time, inputting text with only one hand may be slow and troublesome.
Researchers from Zhejiang University in China have developed a smart application called AirText ,that allows the user to write messages in the air. An application then captures that text and enters it on the device, without the need for the user to touch the screen.
One of the main challenges in developing AirText is how to make it understand the correspondence between wrist movements and fingertip spelling movements.
As shown in the picture below, the trajectory of the wrist when spelling is quite different from the normal letters.
To the end ,the research team first used an off-the-shelf tool Leap Motion, which can track gestures with infrared sensors.Then eight volunteers used five different smart watches to spell out more than 25,000 characters, and used Leap Motion to collect relevant wrist and finger movement data.
The average typing speed of volunteers using AirText was 8.1 words per minute, and their average word error rate was between 3.6% and 11.2%. In order to speed up the writing process, AirText can try to predict the word the user is trying to spell, just like the current word prediction software programs on smartphones. However, there is a limitation, AirText users must pause briefly between spelling out a single character. This method reduces the input speed, and the research team is exploring ways to eliminate this pause.
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