An Underactuated Hand-Exoskeleton with Adaptive Kinematics for Bilateral Rehabilitation

The study introduces a hand exoskeleton designed to assist hand closing and opening. It uses a unique under-actuated kinematics approach adaptable to different hand sizes. This peculiar design applies only linear forces to the finger segments, which helps to overcome problems caused by the flexible connection between the exoskeleton and finger tissues. The system is improved from previous versions for clinical use, with enhanced kinematics layout, more compact flexure hinges, and built-in electronics supporting strain-gauge force sensors for durability and comfort. A control method is also developed for adjusting the grasping assistance based on the patient's evolving motor abilities. This method features symmetric tasks with both the affected and unaffected hand to provide just the necessary support for completing task. This work outlines the hand exoskeleton's design and its initial testing on five healthy participants.