HAPTIC FEEDBACK FOR REHABILITATION SYSTEMS

Abstract

The human sense of touch is an integral part of daily life; the loss of which puts the person at a severe disadvantage. Without this, tasks of grasping and manipulation of objects are next to impossible because feedback of force is a key requirement for them. While most of the systems give contact point or complete grasping force feedback, for precision grasping and other physical interactions finger awareness and force feedback from independent fingers is essential. In this study a wearable vibrotactile haptic feedback (Vi-HaB) system is designed to give individual finger awareness and multiple levels of force feedback from each fingertip for upper limb rehabilitation and teleoperation systems. The system provides simultaneous force feedback from multiple fingers/complete grasping force feedback as well. For testing the system accuracy, classical psychophysical methods were used on a group of 28 voluntary disabled subjects, out of which 14 were able bodied and 14 were disabled. The tests were conducted in both, ideal and real-world conditions i.e. without and with distractions and accuracies were calculated accordingly. A p-test was also conducted to observe significance between the data samples of with and without distraction datasets. The system performed with an overall accuracy of 78.97% with able bodies subjects and 82.04% with disabled subjects which are well above the min. performance measure of 60%. Vi-HaB is standalone system and can be mounted on any upper limb rehabilitation (upper limb prosthesis, exoskeleton) and teleoperation system for finger awareness and force feedback.