Development and Evaluation of a Novel Passive Wrist Bilateral Rehabilitation Device paired with Virtual Reality: A Feasibility Study

This paper introduces a novel passive wrist bilateral rehabilitation device coupled with a new Virtual Reality (VR) platform. This is the first work to have adapted three-link coaxial spherical parallel manipulator (SPM) to wrist rehabilitation. The device comprises a coaxial SPM and cross-connected cable system. The coaxial SPM facilitates 3 degrees of freedom (DOFs) spherical wrist orientation and singularity-free motion within its workspace. The cross-connected cable system enables bilateral symmetrical exercises in passive mode training. A VR platform with activities of daily living (ADL) task was developed and coupled with the device to increase the adherence of the users to the device. Experiments were conducted with fifteen healthy right-handed individuals with no history of wrist or hand injury to evaluate the feasibility of the system for providing passive bilateral training as well as the effectiveness of the VR platform. Subjects were asked to use their right arms to move the left arms passively through the device to perform four wrist movements, flexion, extension, radial deviation, and ulnar deviation. EMG activations on the left arm were observed when the right arm passively moved the left arm. The results showed that the device was capable of inducing the muscle activation of the left arm and the VR platform increased the motivation to continue the exercises. This demonstrates that this study can serve as the fundamental for larger clinical trials.