Stiffness and Mass Distributions of Continuous Models of a Standing Human Body subject to Vertical Vibrations

2011 ◽  
Author(s):  
Q. Zhang ◽  
T. Ji
Keyword(s):  
Human Body ◽  
Mass Distributions ◽  
Continuous Models ◽  
Vertical Vibrations ◽  
Body Subject

scholarly journals Modeling of a Seated Human Body Exposed to Vertical Vibrations in Various Automotive Postures

2008 ◽  
Vol 46 (2) ◽  
pp. 125-137 ◽  
Author(s):  
Cho-Chung LIANG ◽  
Chi-Feng CHIANG
Keyword(s):  
Human Body ◽  
Vertical Vibrations

Investigation of a Vibration Reduction System for Vehicle Seats by a Vibration Model Consisting of a Vehicle, Seat, and Human Body

2013 ◽  
Author(s):  
S. Ota ◽  
S. Nishiyama ◽  
T. Nakamori
Keyword(s):  
Mechanical Properties ◽  
Human Body ◽  
Vibration Reduction ◽  
Steering Wheel ◽  
The Road ◽  
Reduction System ◽  
Vibration Model ◽  
Comparison Results ◽  
Vertical Vibrations ◽  
Calculation System

This paper describes a vibration reduction system that can minimize the vertical vibrations of the human body in a vehicle. This system can control the mechanical properties of the seat cushions, such as the spring constants and damping coefficients. To examine the feasibility of this vibration reduction system, we design a vibration model of both an occupant–seat–steering wheel–pedals–vehicle system and a calculation system. Further, we carry out a numerical analysis to calculate the magnitude of vibrations transmitted from the road surface to the human body based on ISO7096-EM6. Comparison results of the frequency response between the analysis and the experiment indicate the feasibilities of both the vibration model and the analysis method. Furthermore, vibration of the head was reduced 60.1% by controlling the mechanical properties of the seat from 1/5 to 5 times. In summary, the in-vehicle vibration reduction system successfully reduces vibrations from the seat to the human body.

A BIOMECHANICAL MODEL AS A SEATED HUMAN BODY FOR CALCULATION OF VERTICAL VIBRATION TRANSMISSIBILITY USING A GENETIC ALGORITHM

2013 ◽  
Vol 13 (04) ◽  
pp. 1350053 ◽  
Author(s):  
JAVAD MARZBANRAD ◽  
AMIR AFKAR
Keyword(s):  
Genetic Algorithm ◽  
Human Body ◽  
Coupled Model ◽  
Whole Body ◽  
Biomechanical Models ◽  
Mean Error ◽  
Lumped Parameter ◽  
Vertical Vibrations ◽  
Stiffness And Damping ◽  
Multi Body

Many biomechanical models of whole body vibrations have been developed, as part of the design, optimization, and vibrations control of vehicle seat systems, with the aim of achieving greater comfort. Most of these models are complex and result in large errors. In this paper, we introduce two new models, with and without backrest support, within a specific frequency domain. One is an optimized seven-degrees-of-freedom (7-DoF) lumped-parameter model with a unique structure to display vertical vibrations in one direction. The other is a new type of model called the coupled model, where the stiffness and damping matrices are employed instead of the spring and damper scalar parameters to present vertical vibrations in two directions — vertical and horizontal. The use of matrices not only simplifies and reduces DoF, but also gives more accurate results in comparison with the conventional multi-body models. With the help of a genetic algorithm (GA) through the global criterion method, we obtained numerical parameters of both models including mass, stiffness, and damping, which minimized the errors. The mean error for the 7-DoF model was 2.2%, while the best lumped-parameter models previously developed produced 12.6%. For the coupled model, we measured a mean error of 7%, a significant improvement over a well-known multi-body model with a mean error of 22.4%. Finally, we compared the transmissibility of vibrations in the human body applying the two models in the frequency range below 6 Hz, in both cases of with and without a backrest. These confirmed the importance of the backrest.

Investigation of Vehicle Seat With Active Control System to Minimize Vertical Vibrations From Seat to Human Body

2011 ◽  
Author(s):  
S. Ota ◽  
S. Nishiyama
Keyword(s):  
Mechanical Properties ◽  
Control System ◽  
Active Control ◽  
Human Body ◽  
Optimization Algorithm ◽  
Standard Condition ◽  
Optimization Method ◽  
Active Control System ◽  
Vertical Vibrations ◽  
Vehicle Seat

This paper describes an active control system intended to minimize the vertical vibrations transferred from the seat to the human body in a vehicle. This system controls mechanical properties such as the spring constants and damping coefficients of each part of the vehicle seat by using an optimization algorithm that comprises vibration analysis and an optimization method. To examine the feasibility of the optimization algorithm, we designed a vibration model for the seat–occupant system and calculated the reduction in vibration due to the algorithm by numerical analysis. The mechanical properties of the back and front side of the seat were controlled with reference to the standard condition in the range of 1/1.5–1.5 times, 1/2–2 times, and 1/4–4 times. These results suggest that the percentage reduction in vibration for the head—a sensitive part of the human body—because of acceleration in the frequency range of 4–8 Hz was 36%–52%, 40%–63%, and 55%–76%, respectively. In summary, the proposed algorithm successfully reduced vibrations from the seat to the human body in a vehicle.

scholarly journals A study of biomechanical model of seated human body exposed to vertical vibrations

2020 ◽  
Vol 997 ◽  
pp. 012084
Author(s):  
A T Oncescu ◽  
D Tarnita ◽  
D Bolcu ◽  
R Malciu
Keyword(s):  
Human Body ◽  
Biomechanical Model ◽  
Vertical Vibrations
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