Assisted Walking with Hybrid Orthosis Using Functional Electrical Stimulation

Abstract

Neurological disorders affect body mobility, strength and coordination, and can significantly impact the quality of life. For instance, suffering a spinal cord injury (SCI) generally result in permanent lower-limbs paralysis. Robotic assistive devices, such as lower-limb exoskeletons, can help SCI patients to recover their mobility and autonomy in everyday life. Moreover, advances in neuroprosthetics have shown that functional electrical stimulation (FES) can be used to control joint motion by inducing muscle contraction through electrical assistance [1]. Hybrid assistive devices that combine wearable robotics and neuroprosthesis present some advantages compared to robotic assistive devices. Namely, FES-induced muscle contraction activates muscle metabolism, which delays muscle atrophy and promotes cardiovascular activity. However, determining the optimal control strategy of hybrid devices is still a challenge. Here, we present an optimization framework for musculoskeletal models with hybrid assistive devices using the direct collocation method