Fig. 1.

Sample module factorization of a representative subject. a Individual strides (light blue solid) and mean muscle signal (black dot-dash) for the ten muscle signals recorded during walking in an exoskeleton b Individual strides (solid) and mean value (dash) of the timing signal for the six modules extracted using nonnegative muscle factorization. c Weighting signals for the six modules. d The mean measured (light blue solid) and mean reconstructed value (black dot-dash) for the ten muscle signals. e Photo of the subject standing in the exoskeleton. Muscle Abbreviations: Soleus (SO), Tibialis anterior (TA), Peroneus longus (PL), Medial gastrocnemius (MG), Biceps femoris long head (BF), Semitendenosis (SM), Rectus femoris (RF), Vastus lateralus(VL), Vastus medialis(VM), and Gluteus maximus(GX)