High-Precision and Customized Ring-Type Virtual Keyboard Based on Layout Redesign

Virtual keyboards could potentially replace traditional physical keyboards for text input and human-computer-interface due to their portability and comfortable usage characteristics. However, typical virtual keyboards such as wearable keyboards and camera-based keyboards have unsatisfactory input recognition accuracy, and hence, preventing them from gaining pervasive acceptance by users. In this study, we demonstrated that the layout optimization of keyboards can potentially improve recognition accuracy for ring-type motion sensing virtual keyboards, and analyzed several layout designs for the configuration of typing keys. Moreover, we proved that the new layout designs have significant advantages in reducing muscle oppression for the users. The layout designs were mainly improved through three aspects: arc and split design, key position adjustment, and letter arrangement. Three new layouts were tested, which show significant improvements ranging from 5.74% to 7.51% in recognition accuracy, i.e., achieving up to 97.57% accuracy for ring-type virtual keyboards. Additionally, muscle oppression test results (using surface myoelectricity data) indicate that our new keyboard layouts could provide a significant difference (p< 0.05) in reducing muscle oppression from traditional QWERTY keyboards. As for the moving distance of finger tips, our customized layouts could even reduce half of the movement distance compared with traditional keyboards. The experimental results demonstrate that our motion sensing rings combined with customized keyboard layouts could greatly overcome several disadvantages of traditional QWERTY keyboards.