scholarly journals Effect of degeneration on the six degree of freedom mechanical properties of human lumbar spine segments

2016 ◽  
Vol 34 (8) ◽  
pp. 1399-1409 ◽  
Author(s):  
Dhara B. Amin ◽  
Dana Sommerfeld ◽  
Isaac M. Lawless ◽  
Richard M. Stanley ◽  
Boyin Ding ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Lumbar Spine ◽  
Degree Of Freedom ◽  
Human Lumbar Spine ◽  
Six Degree Of Freedom

The effect of six degree of freedom loading sequence on the in-vitro compressive properties of human lumbar spine segments

2016 ◽  
Vol 49 (14) ◽  
pp. 3407-3414 ◽  
Author(s):  
D.B. Amin ◽  
I.M. Lawless ◽  
D. Sommerfeld ◽  
R.M. Stanley ◽  
B. Ding ◽  
...  
Keyword(s):  
Lumbar Spine ◽  
Degree Of Freedom ◽  
Compressive Properties ◽  
Human Lumbar Spine ◽  
Loading Sequence ◽  
Six Degree Of Freedom

Mechanical Properties of Human Lumbar Spine Motion Segments—Part I: Responses in Flexion, Extension, Lateral Bending, and Torsion

1979 ◽  
Vol 101 (1) ◽  
pp. 46-52 ◽  
Author(s):  
A. B. Schultz ◽  
D. N. Warwick ◽  
M. H. Berkson ◽  
A. L. Nachemson
Keyword(s):  
Mechanical Properties ◽  
Lumbar Spine ◽  
Mechanical Behavior ◽  
Human Cadaver ◽  
Lateral Bending ◽  
Human Lumbar Spine ◽  
Flexion Extension ◽  
Spine Motion ◽  
Pressure Changes ◽  
Posterior Elements

In this first part of a three-part report, the mechanical behavior of 42 fresh human cadaver lumbar motion segments in flexion, extension, lateral bending, and torsion is examined. Motions and intradiskal pressure changes that occurred in response to these loads, with posterior elements both intact and excised, are reported.

scholarly journals Finite Element Investigation of the Effects of the Low-Frequency Vibration Generated by Vehicle Driving on the Human Lumbar Mechanical Properties

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Ruo-xun Fan ◽  
Jie Liu ◽  
Yong-li Li ◽  
Jun Liu ◽  
Jia-zi Gao
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Lumbar Spine ◽  
Nucleus Pulposus ◽  
Vibrational Frequency ◽  
Low Frequency ◽  
Fluid Loss ◽  
Low Frequency Vibration ◽  
Human Lumbar Spine

Long-term exposure to low-frequency vibration generated by vehicle driving impairs human lumbar spine health. However, few studies have investigated how low-frequency vibration affects human lumbar mechanical properties. This study established a poroelastic finite element model of human lumbar spinal segments L2–L3 to perform time-dependent vibrational simulation analysis and investigated the effects of different vibrational frequencies generated by normal vehicle driving on the lumbar mechanical properties in one hour. Analysis results showed that vibrational load caused more injury to lumbar health than static load, and vibration at the resonant frequency generated the most serious injury. The axial effective stress and the radial displacement in the intervertebral disc, as well as the fluid loss in the nucleus pulposus, increased, whereas the pore pressure in the nucleus pulposus decreased with increased vibrational frequency under the same vibrational time, which may aggravate the injury degree of human lumbar spine. Therefore, long-term driving on a well-paved road also induces negative effects on human lumbar spine health. When driving on a nonpaved road or operating engineering machinery under poor navigating condition, the auto seat transmits relatively high vibrational frequency, which is highly detrimental to the lumbar spine health of a driver.

Mechanical Properties of Human Lumbar Spine Motion Segments

Spine ◽  
1979 ◽  
Vol 4 (1) ◽  
pp. 1-8 ◽  
Author(s):  
ALF L. NACHEMSON ◽  
ALBERT B. SCHULTZ ◽  
MICHAEL H. BERKSON
Keyword(s):  
Mechanical Properties ◽  
Lumbar Spine ◽  
Human Lumbar Spine ◽  
Spine Motion

Iterative feedback control based on frequency response model for a six-degree-of-freedom micro-vibration platform

2021 ◽  
pp. 107754632199731
Author(s):  
He Zhu ◽  
Shuai He ◽  
Zhenbang Xu ◽  
XiaoMing Wang ◽  
Chao Qin ◽  
...  
Keyword(s):  
Feedback Control ◽  
Frequency Response ◽  
Control Strategy ◽  
Degree Of Freedom ◽  
Small Displacement ◽  
Response Model ◽  
Parameter Uncertainties ◽  
Micro Vibration ◽  
Six Degree Of Freedom ◽  
Iterative Feedback

In this article, a six-degree-of-freedom (6-DOF) micro-vibration platform (6-MVP) based on the Gough–Stewart configuration is designed to reproduce the 6-DOF micro-vibration that occurs at the installation surfaces of sensitive space-based instruments such as large space optical loads and laser communications equipment. The platform’s dynamic model is simplified because of the small displacement characteristics of micro-vibrations. By considering the multifrequency line spectrum characteristics of micro-vibrations and the parameter uncertainties, an iterative feedback control strategy based on a frequency response model is designed, and the effectiveness of the proposed control strategy is verified by performing integrated simulations. Finally, micro-vibration experiments are performed with a 10 kg load on the platform. The results of these micro-vibration experiments show that after several iterations, the amplitude control errors are less than 3% and the phase control errors are less than 1°. The control strategy presented in this article offers the advantages of a simple algorithm and high precision and it can also be used to control other similar micro-vibration platforms.

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