Abstract: This paper is a study on the development of a wearable sensor system
for reading Braille. The study is intended to develop a compact tactile sensor
system which uses a PVDF (Polyvinylidene Fluoride) film as the sensory
receptor. The sensor is mounted onto a fingertip and moved over Braille
manually to obtain the sensor output. Since the unsteady movements yield
variations in the waveforms, a robust recognition system is required. The
recognition system consists of three components as follows. First, the signal
inputted to the system is divided into individual signals regardless of the
variations in the waveforms. Next, those signals are transformed into effective
feature vectors in order to suppress the variations. Finally, those vectors are
classified and the results are obtained. In the process, minimum-distance
classifiers and neural classifiers are used. For the investigation of
experimental verification, test signals are inputted to the recognition system
and the performance of the system is evaluated. The obtained results show that
the wearable sensor with the recognition system is effective to recognize
Braille.
