Wearable force/torque sensor for updating models of paralyzed arms

Our long-term goal is to restore functional reaching movements to people with whole-arm paralysis due to C1-C4 level spinal cord injuries (SCI). The success of functional electrical stimulation (FES) to activate paralyzed muscles to achieve this goal has been limited to laboratory demonstrations using electrical stimulation patterns tuned by technical experts. We have developed a strategy to automatically coordinate muscle stimulation to control shoulder and elbow movements based on subject-specific models of the arm's response to electrical stimulation. To make this strategy effective in people's homes, non-expert users must be able to easily refine the models as the muscles and functional needs of a person with an SCI change over time. This project's goal is to develop an interface that senses the forces and torques applied by a caregiver while guiding the distal forearm of a person with SCI during an FES-controlled reaching movement.