Skip navigation
Please use this identifier to cite or link to this item: http://repository.iitr.ac.in/handle/123456789/18070
Title: Effects of posture and vibration magnitude on seat to head transmissibility during exposure to vertical vibration
Authors: Kaushal M.
Bhiwapurkar M.K.
Saran V.H.
Harsha S.P.
Published in: Proceedings of 20th International Congress on Sound and Vibration 2013, ICSV 2013
Abstract: Humans are most sensitive to whole body vibration under low-frequency excitation in seated posture. Therefore an experimental has been conducted on the vibration simulator developed as a mockup of a railway vehicle. In this paper the effect of variations in posture and vibration magnitude on head motion in three translational axes (X-axis, Y-axis and Z-axis) are studied with Z-axis seat vibration. Thirty healthy male subjects are exposed to random vibration with three vibration magnitudes 0.4, 0.8 and 1.2 m/s2 rms over the frequency range 1-20 Hz. The data results are analyzed in terms of STHT (seat-to-head transmissibility) for head motions in two sitting postures; backrest posture (the subject is seated with backrest support with hands in lap) and forward lean posture (the seated subject leans forward by 200 with hands placed on the table). Vibration measurements in three translation axes of motion at the head are made with an apparatus (bite-bar) specifically developed for this purpose. The data corresponding to each experimental condition is acquired for duration of 160 s, and analyzed to determine STHT, phase and their corresponding coherence functions. The result shows that the single Z-axis seat excitation resulted in head motion to both Z- and X-axis irrespective of the subject postures. As the magnitude of the Z-axis excitation increased from 0.4 to 1.2 m/s2, the principal resonance frequency reduced for both these head motions. The results revealed that both the subject postures have significant influence on the vibration transmission through the upper body. The study confirms that the Z-axis excitation in forward lean posture resonate head most freely in X- and Z-axis at 5 Hz. This experimental study would be useful in vehicle seat design and biodynamic study of human body under low frequency vibration.
Citation: Proceedings of 20th International Congress on Sound and Vibration 2013, ICSV 2013, (2013), 972- 979. Bangkok
URI: http://repository.iitr.ac.in/handle/123456789/18070
Issue Date: 2013
Publisher: International Institute of Acoustics and Vibrations
Keywords: Safety engineering
Coherence function
Experimental conditions
Low-frequency vibration
Principal resonance
Vertical vibrations
Vibration magnitude
Vibration transmission
Whole body vibration
Vibrations (mechanical)
Author Scopus IDs: 56088082100
36633921800
6507475582
6603548398
Author Affiliations: Kaushal, M., Department of Mechanical Engineering, OP Jindal Institute of Technology, Raigarh (CG), India
Bhiwapurkar, M.K., Department of Mechanical Engineering, OP Jindal Institute of Technology, Raigarh (CG), India
Saran, V.H., Department of Mechanical and Industrial Engineering, IIT, Roorkee, Uttarakhand, India
Harsha, S.P., Department of Mechanical and Industrial Engineering, IIT, Roorkee, Uttarakhand, India
Appears in Collections:Conference Publications [ME]

Files in This Item:
There are no files associated with this item.
Show full item record


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.