Presented at the 2nd International Symposium on Innovative Approaches in Scientific Studies (ISAS2018-Winter), Samsun, Turkey, Nov 30, 2018

SETSCI Conference Proceedings, 2018, 3, Page (s): 239-245
, https://doi.org/

Published Date: 31 December 2018    | 1481     13

Lower limb exoskeletons are wearable robotic devices which either augment human power or facilitate a walking
ability for those who lost it by injury or aging. They have been getting more and more attention in the scientific community
thanks to its increasing functionality and availability. Today, several devices are being utilized by people themselves or
rehabilitation centers. Except the fixed gait training systems, these devices are anthropomorphic mechanical structures which
actuated by electric motors, hydraulic or pneumatic cylinders. However, another actuation system so-called pneumatic artificial
muscle (PAM) promises great advantages over its antecedents. It's more compliant, lighter and more powerful. Due to it being a
newer system, one can encounter with it in a few devices and these are either fixed or poorly investigated. This study, along with
its mechanical design choices, gives a deeper insight on usage of PAMs in a lower limb exoskeleton. First, the mechanical system
is designed in SOLIDWORKS with the principles of gait biomechanics. A light-weight design is aimed and a crutch-free system
are planned by placing PAM both sides. In order to examine its strength, finite element analysis is conducted for posture in
ANSYS. It is concluded that the structure can carry both its own and wearers weight. Besides the strength analysis, this study
infers a proof-of-concept that finite element analysis can be used to determine muscle forces for different scenarios when they
are placed properly.  

Keywords - Lower limb exoskeletons, pneumatic artificial muscle, PAM, finite element method, ANSYS

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