TY - JOUR
T1 - A model for flexi-bar to evaluate intervertebral disc and muscle forces in exercises
AU - Abdollahi, Masoud
AU - Nikkhoo, Mohammad
AU - Ashouri, Sajad
AU - Asghari, Mohsen
AU - Parnianpour, Mohamad
AU - Khalaf, Kinda
N1 - Publisher Copyright:
© 2016 IPEM
PY - 2016/10/1
Y1 - 2016/10/1
N2 - This study developed and validated a lumped parameter model for the FLEXI-BAR, a popular training instrument that provides vibration stimulation. The model which can be used in conjunction with musculoskeletal-modeling software for quantitative biomechanical analyses, consists of 3 rigid segments, 2 torsional springs, and 2 torsional dashpots. Two different sets of experiments were conducted to determine the model's key parameters including the stiffness of the springs and the damping ratio of the dashpots. In the first set of experiments, the free vibration of the FLEXI-BAR with an initial displacement at its end was considered, while in the second set, forced oscillations of the bar were studied. The properties of the mechanical elements in the lumped parameter model were derived utilizing a non-linear optimization algorithm which minimized the difference between the model's prediction and the experimental data. The results showed that the model is valid (8% error) and can be used for simulating exercises with the FLEXI-BAR for excitations in the range of the natural frequency. The model was then validated in combination with AnyBody musculoskeletal modeling software, where various lumbar disc, spinal muscles and hand muscles forces were determined during different FLEXI-BAR exercise simulations.
AB - This study developed and validated a lumped parameter model for the FLEXI-BAR, a popular training instrument that provides vibration stimulation. The model which can be used in conjunction with musculoskeletal-modeling software for quantitative biomechanical analyses, consists of 3 rigid segments, 2 torsional springs, and 2 torsional dashpots. Two different sets of experiments were conducted to determine the model's key parameters including the stiffness of the springs and the damping ratio of the dashpots. In the first set of experiments, the free vibration of the FLEXI-BAR with an initial displacement at its end was considered, while in the second set, forced oscillations of the bar were studied. The properties of the mechanical elements in the lumped parameter model were derived utilizing a non-linear optimization algorithm which minimized the difference between the model's prediction and the experimental data. The results showed that the model is valid (8% error) and can be used for simulating exercises with the FLEXI-BAR for excitations in the range of the natural frequency. The model was then validated in combination with AnyBody musculoskeletal modeling software, where various lumbar disc, spinal muscles and hand muscles forces were determined during different FLEXI-BAR exercise simulations.
KW - FLEXI-BAR exercise simulation
KW - Lumped parameter model
KW - Musculoskeletal modeling
UR - http://www.scopus.com/inward/record.url?scp=84979790775&partnerID=8YFLogxK
U2 - 10.1016/j.medengphy.2016.07.006
DO - 10.1016/j.medengphy.2016.07.006
M3 - Article
C2 - 27477521
AN - SCOPUS:84979790775
SN - 1350-4533
VL - 38
SP - 1076
EP - 1082
JO - Medical Engineering and Physics
JF - Medical Engineering and Physics
IS - 10
ER -