Manual Character Transmission by Presenting Trajectories of 7mm-high Letters in One Second
This enables intuitive communication for sighted adults using hands, but it is incremental as it builds on existing haptic feedback methods.
The paper tackled the problem of transmitting symbolic information to untrained users without visual or auditory cues by presenting 3D letter trajectories via a stylus, achieving 71.9% accuracy in first trials and improving to 91.3% after training for 14 mm letters, with retained high accuracy (85.1%) for 7 mm letters.
In this paper, we report a method of intuitively transmitting symbolic information to untrained users via only their hands without using any visual or auditory cues. Our simple concept is presenting three-dimensional letter trajectories to the user's hand via a stylus which is mechanically manipulated. By this simple method, in our experiments, participants were able to read 14 mm-high lower-case letters displayed at a rate of one letter per second with an accuracy rate of 71.9% in their first trials, which was improved to 91.3% after a five-minute training period. These results showed small individual differences among participants (standard deviation of 12.7% in the first trials and 6.7% after training). We also found that this accuracy was still retained to a high level (85.1% with SD of 8.2%) even when the letters were reduced to a height of 7 mm. Thus, we revealed that sighted adults potentially possess the ability to read small letters accurately at normal writing speed using their hands.