Evaluating Approaches to Rendering Braille Text on a High-Density Pin Display

Wearable Assistive Tactile Communication Interface Based on Integrated Touch Sensors and Actuators

This paper presents the design and fabrication of a wearable tactile communication interface with vibrotactile feedback for assistive communication. The interface is based on finger Braille, which is a simple and efficient tactile communication method used by deafblind people. It consists of a flexible piezoresistive sensor and a vibrotactile actuator integrated together and positioned at the index, middle and ring fingers of both hands to represent the six dots of Braille. The sensors were made using flexible piezoresistive material whereas the actuator utilizes electromagnetic principle by means of a flexible coil and a tiny NdFeB permanent magnet. Both were integrated to realize a Bluetooth-enabled tactile communication glove which enables deafblind people to communicate using Braille codes. The evaluation with 20 end-users (10 deafblind and 10 sighted and hearing person) of the tactile interface under standardized conditions demonstrated that users can feel and distinguish the vibration at frequencies ranging from 10Hz to 200Hz which is within the perceivable frequency range for the FA-II receptors. The results show that it took non-experts in Braille within 25s and 55s to send and receive words like "BEST" and "JOURNAL", with an accuracy of ~75% and 68% respectively.