Development of tactile display and an efficient approach to enhance perceptual analysis in rehabilitation

Abstract

Tactile displays are widely used in the rehabilitation and education of blind persons, as it is one of the media of communication amongst them. Tactile display performance is measured in terms of accuracy in presenting pattern, accuracy in identification, recognition and reading time of presented pattern. However, it has had meager attention from researchers. This paper presents a novel 3 x 2 solenoid actuators pin array tactile display and evaluates its effectiveness in presenting alphabets to blind and normal subjects as well as compute facilitation and discrimination value. The proposed actuator requires 75 % of the current and 90 % of the power in comparison with presently available actuators. This is achieved due to the incorporation of conical spring. Two psychological experiments were conducted to evaluate system performance, also to measure perception (reading) and key pressing sense (writing) accuracy for the first time. The low-cost developed system achieved an average reading time of about 15.7 s, recognition time of 39 s and prediction accuracy to be 93 % using a confusion matrix. The developed prototype model has resulted in 94% facilitation value and 11 % discrimination index during psychological experiments for intended users.