Fusing Electrical Stimulation and Wearable Robots with Humans to Restore and Enhance Mobility

Abstract

Participation in everyday life and life satisfaction are greatly affected by disabilities. Motor impairments caused by neurological disorders, like spinal cord injury, stroke, traumatic brain injury, and multiple sclerosis, represent a significant burden for those affected and the society. Wearable robotics and neuroprostheses are two emerging technologies to recover mobility by generating lost movements or amplifying residual weak functions. The suppression of pain, elimination of spasticity, and movement restoration by spinal cord stimulation (i.e. neuromodulation) represent other indirect means for the mobilization of the impaired. This book section introduces the underlying basics of neuroprostheses, spinal cord stimulation, and wearable robotics and highlights recent technological developments with application examples and open challenges. These include using various sensor technologies to recognize the user's intention, generated movement, muscular fatigue, and environmental disturbances. We discuss feedback and learning control as essential solutions for user-individual support and assist-as-needed behavior, and outline hybrid approaches involving multimodal actuation principles to combine the advantages and compensate for the disadvantages of the individual support modalities. Examples of hybrid systems connecting wearable robots and electrical stimulation will illustrate the current state of the art and research before discussing applicability and transfer to daily practice, which does not come without drawbacks.