Synergy matrices to extract fluid wrist motion intents via surface electromyography

This paper presented an estimation method of multi-directional and proportional fluid wrist motion intents via sEMG using a non-negative muscle synergy matrix and a joint synergy matrix. A real-time experiment was performed to validate feasibility of the proposed method, and the experimental environment was realized for the individuals with wrist amputation. Only four wrist movements were predefined (wrist extension, wrist flexion, radial deviation, and ulnar deviation), but the experimental results showed that fluid wrist motion intents (e.g. a combination of wrist extension and ulnar deviation) could be extracted. This work could be useful for the people with wrist amputations to restore their wrist functions using myoelectric powered wrist prosthesis, and also for research to investigate how humans learn myoelectric controls in two-dimensions via training.