Neuroflex – An EMG Driven Wearable Exoskeleton for Dynamic Upper Limb Rehabilitation
DOI:
https://doi.org/10.15662/IJEETR.2026.0802107Keywords:
Neuromuscular Rehabilitation, Surface Electromyography (sEMG), Surface Electromyography (sEMG)ESP32, MPU6050, PCA9685, Assistive Rehabilitation Device, Assistive Rehabilitation DeviceReal-Time Monitoring, Embedded Biomedical Systems, Sustainable Healthcare TechnologyAbstract
Neuromuscular rehabilitation requires precise, repetitive joint actuation integrated with continuous assessment of muscular response to ensure effective therapeutic outcomes. Conventional physiotherapy approaches rely heavily on manual supervision, limiting consistency, quantification, and real-time adaptability during rehabilitation sessions. To overcome these limitations, this study proposes a smart therapeutic flexion rehabilitation system capable of simultaneous muscle activity monitoring, controlled actuation, and real-time feedback delivery within an embedded architecture.
The proposed system is centered on an ESP32 microcontroller, which coordinates multimodal sensing, actuation control, and user interfacing. Muscle activity is acquired using a surface electromyography (sEMG) sensor that captures bioelectrical signals generated during voluntary contractions. Concurrently, joint kinematics are measured using an MPU6050 inertial measurement unit to determine flexion angle and orientation. The acquired signals are processed in real time to evaluate muscle activation levels and dynamically regulate assistive torque requirements. Actuation is achieved through a high-torque servo motor driven via a PCA9685 PWM controller, enabling smooth and controlled flexion–extension assistance during therapy. The system provides continuous visual feedback through an SSD1306 OLED display, presenting key therapeutic parameters including flexion angle, session duration, and categorized muscle strength levels (e.g., low, moderate, high).
Each rehabilitation session is time-regulated to a predefined duration, with automated termination to ensure controlled exposure. Additionally, adaptive termination logic is implemented to halt operation upon detection of sufficient neuromuscular improvement, enhancing both safety and efficiency. A manual override mechanism is incorporated to allow immediate interruption under critical conditions. Experimental validation demonstrates that the system effectively integrates physiological signal monitoring with controlled mechanical assistance, providing consistent rehabilitation support and objective performance feedback. The compact, cost-effective, and portable design facilitates deployment in both clinical and home-based environments. The proposed system contributes to the advancement of intelligent assistive rehabilitation technologies, promoting improved patient outcomes through automation, real-time monitoring, and data-driven therapy. Furthermore, it aligns with global healthcare initiatives by enhancing accessibility to rehabilitation services and supporting sustainable technological innovation in biomedical engineering.
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