Fig. 3.

Example of analysis and results for 1 set of synergies. 10 synergies were specified, and 6 of these synergies were used by the simulation to execute the isometric force task (dark gray bars). The 4 synergies with an activation <0.001 for over 99% of the force directions (light gray bars) were discarded from further analysis. Synergies estimated from each matrix factorization algorithm were paired by greatest correlation coefficient with the specified synergies. In this example, the synergies estimated from NNMF (open bars) had an average normalized similarity of 0.40. The normalized similarity of the NNMF estimated synergies, and specified synergies are shown at the bottom. Muscle abbreviations are defined in Table 1.