Muscle Synergy Analysis of Standing-up Motion with Differing Load Conditions

Abstract

Aiming at application to a device that assists physical human works, the usefulness of muscle synergy in estimation of in standing-up motion with differing load conditions is examined. First, experiments of such a motion are conducted to record surface electromyograms (sEMGs) of six parts of muscles as the muscle activities. Second, muscle synergies are extracted from the sEMGs using the non-negative matrix factorization algorithm. Consequently, it is shown that the motion with differing load conditions can be represented effectively by two muscle synergies. Besides, the amplitude and the start time of the activity coefficients of the muscle synergies correspond to the change of the load conditions. The results suggest that the muscle synergy analysis is useful for the application to a device that assists physical human works.