Biomedical Engineering Reference
In-Depth Information
Fig. 7.49 Lower body model simulated on block-shaped cushion (s = 140 mm) and on
optimized cushion geometry, a deformed cushion shapes at static equilibrium and transversal
section cuts at ischial tuberosity: tissue direct stress S
22
distribution, b direct stress distribution at
the skin level and at the fat-muscle interface
Fig.
7.51
a, as well as in the maximal deformed configuration at static equilibrium,
Fig.
7.51
b, beneath the ischium and lateral to the pelvic bone are compared. The
difference in total displacement of the skin layer at the chosen body sites is
Du
v
=-22 mm vertically and Du
h
= 14 mm horizontally. Tissue displacement is
primarily dependent on the support material and the support geometry. Both
parameters are particularly relevant at off-center regions of the cushion support,
as can be seen in Fig.
7.51
b, where, for illustration purposes, half of the deformed
