Design of a Low-Cost Wrist Rehabilitation Robot for Home Use

Abstract

The primary objective of this study is to develop a lightweight, compact, and portable medical wrist rehabilitation device. The idea behind the project is that the device will be used by the patient, in the comfort of their home; so the device needs to be easy to wear and use, also safety is a key factor. The target users are patients who need assistance with two specific wrist movements - flexion-extension and radial-ulnar deviation. To achieve this objective, 3D CAD models will be developed to design the mechanical components of the robot. Kinematic and kinetic calculations will be done and simulated using tools like Solidworks Motion. Additionally, finite element analysis using software such as Solidworks and ANSYS will analyze component stresses to ensure safety factors for all parts meet or exceed industry standards. After validating the calculations with simulation, the next steps will involve selecting the electric components. This includes choosing two appropriately sized motors, one for each degree of freedom, that will apply sufficient torque for joint movements, without excessive force to disturb the patient based on torque requirements for wrist rehabilitation. In addition, a controller with sufficient processing properties will be evaluated and selected to interface with the motors/drivers. Testing on people with a healthy wrist movement extent will conclude the objectives. The prototype will be tested to verify its performance through quantitative and qualitative feedback. Key metrics for testing will include a range of motion, torque output, electrical current usage, and safety. The design will also be reconsidered based on user feedback to enhance comfort, usability, and ability to smoothly assist natural wrist motions during rehabilitation exercises. Comprehensive documentation of all aspects of the design, development, and testing process will likewise be provided.