Haptic feedback for handwriting training has been extensively studied, but with primary focus on kinematic feedback. We provide vibrotactile feedback through a wrist worn sleeve to guide the user to recreate unknown patterns and study the impact of vibrational duration (1, 2, 3 seconds) on pattern scaling. User traces a line at 90° angles, while attempting to maintain a constant speed, in the direction of the motor activated till a different motor activation is perceived. Shape and size are two features of good letter formation. Study performed on three subjects showed the ability to utilize four vibrotactile motors to guide the hand towards correct shape formation with high accuracy (> 95%). The overall size of the letter was observed to scale linearly with the vibrational duration. Implications for utilizing the vibrational feedback for handwriting correction are discussed.
D. Nair, "Scalability of the size of patterns drawn using tactile hand guidance," In Proc. ACHI 2021, The Fourteenth International Conference on Advances in Computer-Human Interactions, July 2021, pp. 104-110. http://www.thinkmind.org/index.php?view=article&articleid=achi_2021_3_130_20061