An IoT Rehab Device: HHI-based NMES System for Motion Stimulation

Neuromuscular electrical stimulation (NMES) is a new technique applied in rehabilitation therapy for patients to restore or regain their confidence in motor function. This technique is significantly applied to patients suffering from spinal cord injury or stroke. However, there is still a gap for upper limb movement analysis due to the limited number of wearable sensors used in NMES. Therefore, this paper proposed a NMES system coupled with wearable sensors and IoT features for human-to-human interface (HHI) stimulation. The controller (therapist) can copy his/her motion, then paste it into the subject (patient). The controller’s motion signal was injected into the subject through a pulse signal and the subject will repeat the same motion due to stimulation. EMG was attached to the controller to collect the fingers’ flexion and extension. The data will be fed into the control unit for further subject stimulation. An accelerometer was attached to the subject’s fingers for repeating motion evaluation. Performance was calculated based on the difference in flexion and extension angles between controller and subject. The proposed system recorded a 10.3% of error for the first trial and this error was reduced to 1% after five trials.