Article

The mechanical properties of human foot tissue in vivo as well as discomfort and
pain thresholds are important for various applications. In this study, an
apparatus for measuring the discomfort and pain thresholds and the mechanical
properties of human tissues is presented. The apparatus employs a stepper motor
that controls the indentation speed, as well as a load cell and potentiometer
that determine the corresponding reaction force and tissue deformation
(displacement), respectively.
A LabVIEW program (LabVIEW 8, National Instruments
Corporation; Austin, Texas) was developed to control the indentation via a data
acquisition card. The apparatus can accommodate indentor displacements up to 35
mm and can impart forces up to 150 N at a controlled indentation speed in the
range of 0 to 10 mm/s. Tests showed that the displacement measurement error is
<0.17 mm in the nominal range (0.5% in the full scale) and the measurement error
of force is <1.6 N in the nominal range (1.1% in the full scale). Experimental
results indicate that the apparatus is reliable and flexible for measuring the
mechanical properties of foot tissue in vivo in conjunction with pain and
discomfort thresholds.

Langue : ANGLAIS