Biomedical Engineering Reference
In-Depth Information
Fig. 6.36 FE-models with car seat A and human models a E-BCSS 1 and b E-BCSS 2 at static
equilibrium and corresponding node paths below, both in section cut view
The material property evaluation of the car seat systems A and B, cf. Fig.
6.35
,
are described in
Sect. 4.2.2.1
and the employed human body models BoMo7,
BoMo8, BoMo11 and BoMo12 are defined and characterized in
Sect. 5.3.5
.
E-BCSS 1 and E-BCSS 2: Figure
6.36
depicts the investigated FE-interaction
models with a male (E-BCSS 1) and a female (E-BCSS 2) human model. To
compare the mechanical effects on tissue, paths that initiate at skin level and
traverse the tissue towards the bone surface of the ischial tuberosity were gener-
ated. Tissue direct and shear stress and strain at the nodes were evaluated here. The
node path of maximum direct stress S
ii
(i = 1, 2, 3) ended at the bone surface
where maximum vertical (in direction of gravity loading) stress S
33
occurs.
Accordingly, the shear stress S
ij
(i, j = 1, 2, 3, i = j) paths end at the point of
maximum shear stress S
23
, Fig.
6.36
bottom.
Figures
6.37
and
6.38
show the distribution of normal stress S
33
(cf. coordinate
system Fig.
6.36
) and von Mises equivalent stress in the sagital plane at the ischial
tuberosity for models E-BCSS 1 and E-BCSS 2. The tissue stress underneath the
ischium is more intense for the male model than for the female model and the
upper legs of the female model exhibit higher loading. This is mainly due to
different body mass and dissimilar anatomy.
