Research on the Relationship among Contact Force, Finger Movements, and Reading Speed of Braille Readers and on Revising Braille Instruction Methods

点击翻译按钮获取中文摘要

The purpose of our study is (1) to investigate the relation among contact pressure (contact force), finger movements, and the reading skill of braille (reading speed) and (2) to revise braille instruction methods based on above-mentioned experimental results.In 2004, we introduced a pressure measurement system using pressure sensitive conductive ink. From 2004 to early 2005, we performed experiments using this system with skilled braille readers as subjects and observed (1) small but frequent variance of contact pressure within one line and (2) reduced pressure during the sweeps from the end of one line to the beginning of the next line.However, periodic calibration over weeks showed their instability behaviors so that we cannot be confident enough in these quantitative data.To obtain trustworthy pressure data, we adopted an optical 6-axis force-torque sensor in late 2005. Two calibrations over one month proved high accuracy and time stability of the new system.By using this system, we carried out a series of experiments with thirty-two braille users as subjects. Quantitative data demonstrate that unskilled readers show fluctuating but light contact force whereas that of skilled readers are comparatively strong and varies greatly from person to person; these observations are incompatible with the proposition by preceding studies. We analyzed the relationship among braille reading speed, contact force, tactile movements, and attributes of the subjects thoroughly and found that braille reading speed is related to the age when braille was learned and the frequency of braille usage but not to tactile movements.Our future work is to revise braille instruction methods based on these new findings to reduce cognitive workload of braille learners.