I-Keyboard: Fully Imaginary Keyboard on Touch Devices Empowered by Deep Neural Decoder

IEEE TRANSACTIONS ON CYBERNETICS 1 I-Keyboard: Fully Imaginary Keyboard on Touch Devices Empowered by Deep Neural Decoder Ue-Hwan Kim, Sahng-Min Y oo and Jong-Hwan Kim, Fellow, IEEE Abstract --T ext-entry aims to provide an effective and efficient pathway for humans to deliver their messages to computers. With the advent of mobile computing, the recent focus of text-entry research has moved from physical keyboards to soft keyboards. T o tackle these limitations, we propose a fully imaginary keyboard (I-Keyboard) with a deep neural decoder (DND). The invisibility of I-Keyboard maximizes the usability of mobile devices and DND empowered by a deep neural architecture allows users to start typing from any position on the touch screens at any angle. T o the best of our knowledge, the eyes-free ten-finger typing scenario of I-Keyboard which does not necessitate both a calibration step and a predefined region for typing is first explored in this work. For the purpose of training DND, we collected the largest user data in the process of developing I-Keyboard. We verified the performance of the proposed I-Keyboard and DND by conducting a series of comprehensive simulations and experiments under various conditions. I-Keyboard showed 18.95% and 4.06% increases in typing speed (45.57 I NTRODUCTION T EXT-entry takes a crucial role in human-computer interaction (HCI) applications [1]. It is one of the most effective and efficient methods for humans to deliver messages to computers. In the early stage of HCI research, physical keyboard-based text-entry methods were prevailing. Since then, researchers have focused on designing keyboards with high usability. In the post-PC era, the birth of mobile [2] and ubiquitous computing have prompted the development of soft keyboards. Soft keyboards [3] set mobile devices free from equipping additional hardware, thus improve the mobility of mobile devices. However, contemporary soft keyboards possess a few limitations. In fact, current soft keyboard techniques damage the usability of mobile devices in multiple ways other than the mobility. First, the lack of tactile feedback increases the rate of typos.