Fingertip Force Learning with Enhanced Haptic Sensation using Stochastic Resonance

In many haptic training systems, the users need to wear a finger holder in order to interact with the system and learn fine motor skills. This procedural requirement of using a finger holder is known to decrease the user force-detection capability at the fingertip, which could lead to poor learning outcomes. In order to increase the fingertip force-detection capabilities of the user, one possible way is to use Stochastic Resonance (SR). However, the effects of SR on a fingertip placed inside a finger holder are hitherto unknown. In this paper, first we investigate the effects of SR on the user haptic performance when the fingertip is placed inside a finger holder. Then, we propose a new haptic training method that utilizes haptic feedback and SR to improves the user performance outcomes. The results show that the user fingertip sensitivity significantly increases even when the fingertip is enclosed by a finger holder. We performed a force learning task to compare the user performance under two conditions: (i) haptic feedback with SR (proposed method), and (ii) haptic feedback without SR. The results demonstrate that the user performance, measured through task accuracy, increases with the proposed method. These findings indicate the effectiveness of the proposed haptic training method and application of SR in motor-skill learning.