TY - JOUR
T1 - Alignment of a single-axis passive knee
T2 - 8th Meeting of the European Society of Biomechanics 1992
AU - Koopman, H.F.J.M.
AU - Grootenboer, H.J.
N1 - Conference code: 8
PY - 1993
Y1 - 1993
N2 - An inverse dynamics technique was used to numerically predict the movement of walking with a passive, single-axis right knee. Starting from an initial movement, the solution was found by successiveit erations while minimizing a general criterion of walking. For the initial movement, a measured walking pattern with the right knee immobilixed was chosen. The optimization criterion consisted of a fatigue criterion, mostly depending on the calculated joint moments of force, with additional constraints describing the passive properties of the right knee. The investigated alignment-pammemr was the backward displacement d of the knee-axis relative to the original location. The computed results were compared to what is known from prosthetic pm&se. During single stance no flexion occurs. According to what would be expected, the maximal flexion decreases when the knee is placed more backwards. When the predicted step-parametersfo r the passivek nee am compared with the data of the stiff knee, it is seent hat the symmetry mcreases for the step time but decreases for the step length. As expected, it will cost more energy (according to the fatigue criterion) to walk with a passive knee. With increasing d, the energy cost decreases, since less energy is needed to stabilize the knee joint with the hip musculature during stance.
AB - An inverse dynamics technique was used to numerically predict the movement of walking with a passive, single-axis right knee. Starting from an initial movement, the solution was found by successiveit erations while minimizing a general criterion of walking. For the initial movement, a measured walking pattern with the right knee immobilixed was chosen. The optimization criterion consisted of a fatigue criterion, mostly depending on the calculated joint moments of force, with additional constraints describing the passive properties of the right knee. The investigated alignment-pammemr was the backward displacement d of the knee-axis relative to the original location. The computed results were compared to what is known from prosthetic pm&se. During single stance no flexion occurs. According to what would be expected, the maximal flexion decreases when the knee is placed more backwards. When the predicted step-parametersfo r the passivek nee am compared with the data of the stiff knee, it is seent hat the symmetry mcreases for the step time but decreases for the step length. As expected, it will cost more energy (according to the fatigue criterion) to walk with a passive knee. With increasing d, the energy cost decreases, since less energy is needed to stabilize the knee joint with the hip musculature during stance.
U2 - 10.1016/0021-9290(93)90628-R
DO - 10.1016/0021-9290(93)90628-R
M3 - Meeting Abstract
SN - 0021-9290
VL - 26
SP - 877
EP - 877
JO - Journal of biomechanics
JF - Journal of biomechanics
IS - 7
Y2 - 21 June 1992 through 24 June 1992
ER -