| Περίληψη: | Over the past decades, the field of knee joint simulating devices has been constantly evolving. Different
kinds of experimental simulators offered valuable insight over kinematic and loading behavior of a natural
or artificial knee joint. However, as human life expectancy constantly increases, people tend to experience
more and more fatigue around their knee joint, resulting in intense wear and pain, thus experiments over
the new prosthetic technologies introduced have to accommodate accelerated and more demanding
testing regimes of variant daily and sport activities.
The main objective of this study was to develop a novel dynamic knee simulator that not only abide to but
surpassed the requirements of the ISO 14243 Standard [1, 2], including the operating frequency,specimen
mounting, positioning & alignment, range of motion and in-vitro conditions such as the incorporation of
lubrication, temperature, and pH control systems.
The first development step included the conceptual design of the simulator and its optimization using
CATIA (Dassault Systèmes, Vélizy-Villacoublay, France) designing software, where factors such as design
for assembly (DFA), design for manufacturing (DFM), ease of maintenance, safety measures and
modularity determined the final result. Some of the key characteristics of the apparatus were the 6
degrees of freedom permitted between the two articulating bones with five controlled axes, the option
to mount and investigate the performance of specimens regardless of their size, as well as a custom fluid
test medium enclosing capsule that did not interfere with the outgoing procedure, even at the maximum
flexion angle of 120 degrees.
The next step was to investigate the structural integrity of the conceptual design introduced, by imposing
severe static loading conditions to replicate complex daily activities by using the ANSYS Static structural
software. Finally, through a modal analysis, vibration characteristics were inspected to ensure that the
machine operated at a frequency different from its natural ones, so resonance could be avoided.
Throughout the simulations, a mesh independence study in conjunction with non-linearities were
included, to obtain more realistic and accurate results. According to the findings of this study, the
introduced conceptual design of the knee simulating device was functional and reliable.
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