Advancing upper-limb neuro-rehabilitation with a modular shuolder-elbow-hand exoskeleton for proximal-to-distal support

Population ageing trend and increasing incidence of neurological diseases raise the need of enhancing effectiveness and efficiency of rehabilitation treatment. In this context, exoskeletons serve as a versatile tool that can assist both patients and healthcare providers throughout the entire process, from diagnosis to treatment. In this work two novel platforms for the neurological treatment of severely impaired patients are presented; specifically the NESM-γ is intended to assist the shoulder and elbow districts and the MITEx targets the treatment of index and thumb. Different control strategies are implemented for a safe engagement with the final users, sharing the interaction between the robot and the human depending on the intended tailored therapy; torque and impedance control are implemented to offer different rehabilitation paradigms. The devices are systematically validated in terms of kinematic compatibility and functionalities of mechatronics solutions adopted, in an healthy population. Benefitting from their modular design, the two devices are successively integrated in a single full-exo platform, capable of offering whole-arm exercises; a strategy for coordinated mobilization of proximal and distal joints of the upper limb enables performing of functional tasks, to enhance coherence between motion planning and execution. Extending the concept, to alternatively assist distal joints, a functional electrical stimulation (FES) module is integrated to realize an hybrid exoskeleton; a cooperative control redistributes the control effort between the exoskeleton and the FES at the elbow. Both configurations gave birth to the ReHyb High-Powered Platform, for patients at early stages of recovery, whose feasibility and functionality is tested in a clinical multicentric study with a stroke population. Data collected from the platforms, including kinematic joint angles, torques, and stimulation currents, provide insights into the patient’s condition throughout the treatment protocol, and they can infer short-term effects of such treatment.