An sEMG-based Contralateral Functional Electrical Stimulation Control Strategy Via Joint Angle Mapping

Functional electrical stimulation (FES) has been widely applied in stroke rehabilitation, but existing systems often lack continuous adjustment based on patient-specific feedback. This study presents a contralaterally controlled stimulation system that introduces the wrist joint angle as an intermediate variable, establishing two mappings: (1) from surface electromyography (sEMG) of the unaffected side to joint angles via a two-layer long short-term memory network (LSTM), and (2) from stimulation current to joint angles on the affected side using nonlinear fitting. This design enables real-time closed-loop modulation of stimulation parameters, allowing the affected limb to mirror unaffected-side movements, thereby enhancing patient engagement and potentially accelerating motor function recovery. The prediction accuracy and bilateral trajectory correlation obtained from experiments with healthy subjects and stroke patients demonstrate the system’s feasibility and rehabilitation potential.