Seated body apparent mass response to vertical whole body vibration: Gender and anthropometric effects

Abstract The gender and anthropometric effects on apparent mass characteristics of the seated body exposed to vertical vibration are investigated through laboratory measurements. The study was conducted on 31 male and 27 female subjects, exposed to three levels of vertical vibration (0.25, 0.50 and 0.75 m/s2 rms acceleration) in the 0.50 to 20 frequency range, while seated without a back support and against a vertical back support. The apparent mass responses were analyzed by grouping datasets in three ranges of mass-, build- and stature-related parameters for the male and female subjects. Comparisons of responses of male and female subjects with comparable anthropometric properties showed distinctly different biodynamic responses of the two genders. The primary resonance frequency of male subjects was significantly (p   0.7), irrespective of the back support and excitation conditions for both the genders. Relevance to the industry The apparent mass responses of the human body exposed to whole-body vibration form an essential basis for an understanding of mechanical-equivalent properties of the body, developments in frequency-weightings for assessment of exposure risks and anthropodynamic manikins for assessment of seats. The effects of gender and anthropometric parameters on the AM response are vital for seeking better seat designs, and anthropodynamic manikins for assessments of seating for male as well as female workers.

[1]  M Fritz,et al.  Simulating the response of a standing operator to vibration stress by means of a biomechanical model. , 2000, Journal of biomechanics.

[2]  Subhash Rakheja,et al.  Influence of support conditions on vertical whole-body vibration of the seated human body. , 2010, Industrial health.

[3]  Toshisuke Miwa.  MECHANICAL IMPEDANCE OF HUMAN BODY IN VARIOUS POSTURES , 1975 .

[4]  C. Bonthoux,et al.  Biodynamic response of the human body in the sitting position when subjected to vertical vibration , 1983 .

[5]  Subhash Rakheja,et al.  Effects of sitting postures on biodynamic response of seated occupants under vertical vibration , 2004 .

[6]  Michael J. Griffin,et al.  Vertical and dual-axis vibration of the seated human body: Nonlinearity, cross-axis coupling, and associations between resonances in transmissibility and apparent mass , 2012 .

[7]  J. Bendat,et al.  Random Data: Analysis and Measurement Procedures , 1971 .

[8]  M. Griffin,et al.  Non-linearities in apparent mass and transmissibility during exposure to whole-body vertical vibration. , 2000, Journal of biomechanics.

[9]  D. E. Welcome,et al.  Contact pressure distribution at hand–handle interface: role of hand forces and handle size , 2005 .

[10]  Setsuo Maeda,et al.  Comparison of the apparent mass of the seated human measured using random and sinusoidal vibration. , 2005, Industrial health.

[11]  C. Warren,et al.  Biodynamics of the human body under whole-body vibration: Synthesis of the reported data , 2010 .

[12]  Ion Stiharu,et al.  Seated occupant interactions with seat backrest and pan, and biodynamic responses under vertical vibration , 2006 .

[13]  R Lundström,et al.  Mechanical impedance of the human body in vertical direction. , 2000, Applied ergonomics.

[14]  James A. Hodgdon,et al.  Prediction of Percent Body Fat for U.S. Navy Women from Body Circumferences and Height , 1984 .

[15]  Patrik Holmlund.  Absorbed Power and Mechanical Impedance of the Seated Human Measured within a Real Vehicle Environment Compared with Single Axis Laboratory Data , 1999 .

[16]  Cees W J Oomens,et al.  Does subcutaneous adipose tissue behave as an (anti-)thixotropic material? , 2010, Journal of biomechanics.

[17]  M.G.R. Toward.  Effect of backrest interaction on seat cushion transmissibility , 2001 .

[18]  Subhash Rakheja,et al.  ANALYSES OF BIODYNAMIC RESPONSES OF SEATED OCCUPANTS TO UNCORRELATED FORE-AFT AND VERTICAL WHOLE-BODY VIBRATION , 2011 .

[19]  Subhash Rakheja,et al.  SEATED OCCUPANT APPARENT MASS CHARACTERISTICS UNDER AUTOMOTIVE POSTURES AND VERTICAL VIBRATION , 2002 .

[20]  M. Griffin,et al.  Resonance behaviour of the seated human body and effects of posture. , 1997, Journal of biomechanics.

[21]  H. Mertens,et al.  Nonlinear behavior of sitting humans under increasing gravity. , 1978, Aviation, space, and environmental medicine.

[22]  R Lundström,et al.  Absorption of energy during vertical whole-body vibration exposure. , 1998, Journal of biomechanics.

[23]  C F Abrams,et al.  Application of a damped spring-mass human vibration simulator in vibration testing of vehicle seats. , 1969, Ergonomics.

[24]  Michael J. Griffin,et al.  Effects of posture and vibration magnitude on apparent mass and pelvis rotation during exposure to whole-body vertical vibration , 2002 .

[25]  Martin Fritz.  Dynamic Properties of the Biomechanical Model of the Human Body-Influence of Posture and Direction of Vibration Stress , 2005 .

[26]  S. K. Patra,et al.  Determination of reference values of apparent mass responses of seated occupants of different body masses under vertical vibration with and without a back support , 2008 .

[27]  Setsuo Maeda,et al.  Determination of backrest inclination based on biodynamic response study for prevention of low back pain. , 2010, Medical engineering & physics.

[28]  Subhash Rakheja,et al.  Effect of Back Support Condition on Seat to Head Transmissibilities of Seated Occupants under Vertical Vibration , 2006 .

[29]  Robert A. Robergs,et al.  Exercise Physiology: Exercise, Performance, and Clinical Applications , 1997 .

[30]  N J Mansfield,et al.  Effect of vibration magnitude, vibration spectrum and muscle tension on apparent mass and cross axis transfer functions during whole-body vibration exposure. , 2006, Journal of biomechanics.

[31]  M. Griffin,et al.  MOVEMENT OF THE UPPER-BODY OF SEATED SUBJECTS EXPOSED TO VERTICAL WHOLE-BODY VIBRATION AT THE PRINCIPAL RESONANCE FREQUENCY , 1998 .

[32]  Michael J. Griffin,et al.  MATHEMATICAL MODELS FOR THE APPARENT MASS OF THE SEATED HUMAN BODY EXPOSED TO VERTICAL VIBRATION , 1998 .

[33]  Michael J. Griffin,et al.  The apparent mass of the seated human body in the fore-and-aft and lateral directions , 1990 .

[34]  Ronnie Lundström,et al.  ABSORPTION OF ENERGY DURING WHOLE-BODY VIBRATION EXPOSURE , 1998 .

[35]  Michael J. Griffin,et al.  Apparent mass of the human body in the vertical direction: Inter-subject variability , 2011 .

[36]  Neil J. Mansfield,et al.  APPARENT MASS AND ABSORBED POWER DURING EXPOSURE TO WHOLE-BODY VIBRATION AND REPEATED SHOCKS , 2001 .

[37]  M J Griffin,et al.  The apparent mass of the seated human body: vertical vibration. , 1989, Journal of biomechanics.

[38]  A Cullmann,et al.  Design of an active vibration dummy of sitting man. , 2001, Clinical biomechanics.

[39]  Yi Gu,et al.  A New Dummy for Vibration Transmissibility Measurement in Improving Ride Comfort , 1999 .

[40]  Michael J. Griffin,et al.  Effect of seat surface angle on forces at the seat surface during whole-body vertical vibration , 2005 .

[41]  Michael J. Griffin,et al.  Individual variability and its effect on subjective and biodynamic response to whole-body vibration , 1978 .

[42]  H P Wölfel,et al.  Determination of vibration-related spinal loads by numerical simulation. , 2001, Clinical biomechanics.

[43]  Subhash Rakheja,et al.  Apparent mass and head vibration transmission responses of seated body to three translational axis vibration , 2012 .

[44]  B Hinz,et al.  The nonlinearity of the human body's dynamic response during sinusoidal whole body vibration. , 1987, Industrial health.

[45]  R R COERMANN,et al.  The Mechanical Impedance of the Human Body in Sitting and Standing Position at Low Frequencies , 1962, Human factors.

[46]  R Lundström,et al.  Mechanical impedance of the sitting human body in single-axis compared to multi-axis whole-body vibration exposure. , 2001, Clinical biomechanics.

[47]  Barbara Hinz,et al.  EFFECTS RELATED TO RANDOM WHOLE-BODY VIBRATION AND POSTURE ON A SUSPENDED SEATWITH AND WITHOUT BACKREST , 2002 .