Preprint Article Version 1 Preserved in Portico This version is not peer-reviewed

Design and Characterization of a Self-Aligning End-Effector Robot for Single-Joint Arm Movement Rehabilitation

Version 1 : Received: 29 July 2023 / Approved: 31 July 2023 / Online: 1 August 2023 (03:29:32 CEST)

A peer-reviewed article of this Preprint also exists.

Mathavan Jeyabalan, P.K.; Nehrujee, A.; Elias, S.; Magesh Kumar, M.; Sujatha, S.; Balasubramanian, S. Design and Characterization of a Self-Aligning End-Effector Robot for Single-Joint Arm Movement Rehabilitation. Robotics 2023, 12, 149. Mathavan Jeyabalan, P.K.; Nehrujee, A.; Elias, S.; Magesh Kumar, M.; Sujatha, S.; Balasubramanian, S. Design and Characterization of a Self-Aligning End-Effector Robot for Single-Joint Arm Movement Rehabilitation. Robotics 2023, 12, 149.

Abstract

Traditional end-effector robots for arm rehabilitation are usually attached a­t the hand, primarily focusing on coordinated multi-joint training. Therapy at an individual joint level of the arm for severely impaired stroke survivors is not always possible with existing end-effector robots. The Arm Rehabilitation Robot (AREBO)—an end-effector robot—was designed to provide both single and multi-joint assisted training while retaining the advantages of traditional end-effector robots, such as ease of use and cost-effectiveness (compared to exoskeletons). This work presents the design, optimization, and characterization of AREBO for training single-joint movements of the arm. The AREBO has three actuated and three unactuated degrees of freedom, allowing it to apply forces in any arbitrary direction at its endpoint and self-align to arbitrary orientations within its workspace. The AREBO’s link lengths were optimized to maximize its workspace and manipulability. The AREBO provides single-joint training in both unassisted and adaptive weight support modes using a human arm model to estimate the human arm's kinematics and dynamics without using additional sensors. The characterization of the robot’s controller and the algorithm for estimating the human arm parameters were performed using a two degrees of freedom mechatronic model of the human shoulder joint. The results demonstrate that: (a) the movements of the human arm can be estimated using a model of the human arm and robot’s kinematics, (b) the AREBO has similar transparency to that of existing arm therapy robots in the literature, and (c) the adaptive weight support mode control can adapt to different levels of impairment in the arm. This work demonstrates how an appropriately designed end-effector robot can be used for single-joint training, which can be easily extended to multi-joint training. Future work will focus on the evaluation of the system on patients with any neurological condition requiring arm training.

Keywords

stroke; neurorehabilitation; arm rehabilitation robot; transparency; adaptive weight support; end-effector robot

Subject

Engineering, Bioengineering

Comments (0)

We encourage comments and feedback from a broad range of readers. See criteria for comments and our Diversity statement.

Leave a public comment
Send a private comment to the author(s)
* All users must log in before leaving a comment
Views 0
Downloads 0
Comments 0
Metrics 0


×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.
We use cookies on our website to ensure you get the best experience.
Read more about our cookies here.