TY - GEN
T1 - Quantitative characterization of steady-state ankle impedance with muscle activation
AU - Lee, Hyunglae
AU - Ho, Patrick
AU - Rastgaar, Mohammad A.
AU - Krebs, Hermano Igo
AU - Hogan, Neville
PY - 2010
Y1 - 2010
N2 - Characterization of multi-variable ankle mechanical impedance is crucial to understanding how the ankle supports lower-extremity function during interaction with the environment. This paper reports quantification of steady-state ankle impedance when muscles were active. Vector field approximation of repetitive measurements of the torque-angle relation in two degrees of freedom (inversion/eversion and dorsiflexion/plantarflexion) enabled assessment of spring-like and non-spring-like components. Experimental results of eight human subjects showed direction-dependent ankle impedance with greater magnitude than when muscles were relaxed. In addition, vector field analysis demonstrated a non-spring-like behavior when muscles were active, although this phenomenon was subtle in the unimpaired young subjects we studied.
AB - Characterization of multi-variable ankle mechanical impedance is crucial to understanding how the ankle supports lower-extremity function during interaction with the environment. This paper reports quantification of steady-state ankle impedance when muscles were active. Vector field approximation of repetitive measurements of the torque-angle relation in two degrees of freedom (inversion/eversion and dorsiflexion/plantarflexion) enabled assessment of spring-like and non-spring-like components. Experimental results of eight human subjects showed direction-dependent ankle impedance with greater magnitude than when muscles were relaxed. In addition, vector field analysis demonstrated a non-spring-like behavior when muscles were active, although this phenomenon was subtle in the unimpaired young subjects we studied.
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U2 - 10.1115/DSCC2010-4062
DO - 10.1115/DSCC2010-4062
M3 - Conference contribution
AN - SCOPUS:79958229331
SN - 9780791844175
T3 - ASME 2010 Dynamic Systems and Control Conference, DSCC2010
SP - 321
EP - 323
BT - ASME 2010 Dynamic Systems and Control Conference, DSCC2010
T2 - ASME 2010 Dynamic Systems and Control Conference, DSCC2010
Y2 - 12 September 2010 through 15 September 2010
ER -