. Author manuscript; available in PMC: 2013 Mar 4.

Published in final edited form as: J Rehabil Res Dev. 2012;49(2):279–296. doi: 10.1682/jrrd.2010.12.0235

TABLE III.

ARTIFICIAL NEURAL NETWORK (ANN) EXCITATION OUTPUT RESULTS: SENSITIVITY AT ZERO ACCELERATION AND MEAN ANN PREDICTION ERROR

Muscle Group (Right)

\frac{\partial excit}{\partial a_{COM - A P}}

\frac{\partial excit}{\partial a_{COM - M L}}

Mean Error in ANN output (excitation)

Soleus

−0.415

0.000

1.57e-4

Tibialis Anterior

N/A

Vasti

0.000

< 1e-5

Adductor Magnus

−0.006

0.151

2.47e-4

Gluteus Maximus

N/A

Gluteus Medius

−0.047

−0.330

1.84e-4

Semimembranosus

1.095

0.172

3.94e-4

Erector Spinae

0.000

5.27e-5

N/A for muscle groups either not targeted for feedback control or always fully activated.