Design Optimization and Integrated Simulation Analysis of a Cable-Driven Ankle Rehabilitation Robot

Sprained ankles are the most commonly diagnosed injury seen by healthcare providers and are projected to account for up to 30% of sports medicine injuries, with lateral ankle sprain being the most common type. Ankle injuries necessarily involve motion assistance to regain mobility, but physiotherapists are typically able to provide rehabilitation only for one patient at each session. Numerous robotic rehabilitation strategies have been proposed in recent years; however, most of the designs have some limitations such as requiring the patient to sit or stand still. Hence, this study aims to develop a conceptual design and simulation of a compact wearable robot in aiding ankle motion for rehabilitation and training purposes. The cable-driven parallel architecture used in the construction of the cable-driven ankle rehabilitation robot allows for the exercise of the human ankle’s range of motion (ROM) to be maximized. The morphological chart analysis was created to explore the possible solutions to the design development for the ankle rehabilitation device, and the final design was decided using the Pugh method. A three-dimensional model of the proposed design was visualized in SolidWorks to analyze the inverse kinematics, trajectory simulation and cable length analysis. The feasibility of the ankle rehabilitation robot was examined against the simulation and was found to meet the requirements for performing effective ROM exercises for ankle rehabilitation. The proposed design could potentially be used for passive ankle joint rehabilitation exercise in specific ROM, particularly for bedridden patients.