Biomedical Engineering Reference
In-Depth Information
Fig. 3.3 Description of a stereotyped gait cycle with averaged trajectories for the joint angles
(ankle, knee and hip joints), the body segment orientations (foot, shank and thigh), and the height of
heels and toes (adapted from [ 11 ]). The bottom part of the figure depicts how the stance and swing
phases occur in the gait cycle
Human walking is generally described using joint angle trajectories, which exhibit
a typical shape as shown in Fig. 3.3 [ 11 , 85 ].
Some authors have highlighted statistical significant correlations between global
parameters, such as step frequency, length and speed, and knee angles [ 34 ]. Knee flex-
ion during the stance phase could be extrapolated from step frequency SF (expressed
in steps per minutes) with the following equation:
(
) =
.
โˆ’
.
(
=
.
)
Stance Phase Flexion
deg
0
27 SF
5
50
R
0
74
Knee flexion during swing phase is given by:
Swing Phase Flexion
(
deg
) =
0
.
19 SF
+
41
.
4
(
R
=
0
.
68
)
The same kind of correlations can be expressed between stride length SL (m) and
these knee angles:
Stance Phase Flexion
(
deg
) =
26
.
2SL
โˆ’
16
.
8
(
R
=
0
.
79
)
Swing Phase Flexion
(
deg
) =
16
.
0SL
+
37
.
5
(
R
=
0
.
62
)
s โˆ’ 1 ) is correlated with the same angles:
In the same manner speed S (m
ยท
Stance Phase Flexion
(
deg
) =
13
.
0S
+
4
.
7
(
R
=
0
.
78
)
Swing Phase Flexion
(
deg
) =
8
.
6S
+
49
.
6
(
R
=
0
.
66
)
Search WWH ::




Custom Search