DEVELOPMENT OF CAPACITIVE TOUCH CONTROL FABRIC KEYBOARD

Abstract

Flexible fabric keyboard is a field of smart textile. It can overcome traditional horniness keyboard can't be foldable and washing. To overcome the problems such as low resolution and complicated structure that are associated with the existing fabric keyboard device，based on the capacitive touch principle a flexible touch control fabric keyboard device is developed using a double-layer conductive fabric as its touchpad． When a working area in the touch pad is set as 126 mm ×72 mm，with 72 mm side length of L-shape electrode，the test results show that the linearity of the touch control device in X and Y directions is ±4. 40% and ±4. 39%，respectively，and that the resolution reaches as high as 251 dpi × 243 dpi． For further discussion on the controlling accuracy of the device， the deviation rate is defined． The test results show that the control positions，of which the deviation rates are greater than 6%，are located near the edges of the working area． In addition， increasing the side length of the L-shape electrodes has positive but limited effects on the improvement of the linearity． Therefore，it would be preferable to use point electrodes for flexibility and wearablity．