scholarly journals Analytical and Numerical Investigations of Mechanical Vibration in the Vertical Direction of a Human Body in a Driving Vehicle using Biomechanical Vibration Model

2021 ◽  
Vol 29 (4) ◽  
Author(s):  
Maher Al-Baghdadi ◽  
Muhsin Jaber Jweeg ◽  
Muhannad Al-Waily
Keyword(s):  
Dynamic Response ◽  
Human Health ◽  
Human Body ◽  
Mechanical Response ◽  
Ride Comfort ◽  
Vertical Direction ◽  
Sitting Posture ◽  
Vibration Model ◽  
Comparison Results ◽  
And Performance

The main reason that affects the discomfort in a driving vehicle is the vibration response. The human body vibration leads to many malfunctions in both comfort and performance in human health. As a result, the human body’s simulation in sitting posture in the driving vehicle has a strategic relationship for all Tires and vehicles manufacturers. The digital process simulation of the human body seat vehicle vibration shows two significant advantages. The first advantage is the prevention of the high-cost modifications in the construction stage of the vehicle, while the second one describes the stability test during the undesirable vibrations. This study modelled the human body’s dynamic characterisations, natural frequency, and mechanical response when seated in the driving vehicle with vibration transmissibility in the vertical direction have been using the biomechanical vibration model. The vertical vibrations and the transmissibility of the human body dynamic response are presented in detail. Exciting results have been obtained, and they are significant for human health, which relates to sitting posture in the driving vehicle. It can assist in understanding the influences of low-frequency vibration on human health, comfort, and performance, and therefore it could be applied for ride comfort evaluation. An analytical solution to derive the general equations of motion for the human system was developed. Then, using the vibration analysis technique and the corresponding equations, the accurate dynamic response of the selected mode is identified. Furthermore, the mathematical modelling for free vibration using the finite element analysis has been performed to determine the appropriate values and set its description. Then, the comparison results of the two techniques have been carried out.

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.

Modal analysis of human body vibration model for Indian subjects under sitting posture

Ergonomics ◽  
2014 ◽  
Vol 58 (7) ◽  
pp. 1117-1132 ◽  
Author(s):  
Ishbir Singh ◽  
S.P. Nigam ◽  
V.H. Saran
Keyword(s):  
Modal Analysis ◽  
Human Body ◽  
Sitting Posture ◽  
Body Vibration ◽  
Vibration Model

Techniques for Determining the Parameters of a Two-Dimensional Tire Model for the Study of Ride Comfort

1997 ◽  
Vol 25 (3) ◽  
pp. 187-213 ◽  
Author(s):  
F. Mancosu ◽  
G. Matrascia ◽  
F. Cheli
Keyword(s):  
Physical Properties ◽  
Ride Comfort ◽  
Dynamic Test ◽  
Longitudinal Direction ◽  
Tire Model ◽  
Rigid Ring ◽  
Ring Model ◽  
Mass Moment ◽  
A New Technique ◽  
And Performance

Abstract A rigid ring model of the tire for the study of in-plane dynamics and a new technique for determining the parameters of the model are presented in this paper. This model can be used for studying the comfort of vehicles, problems of driving, and braking problems in the longitudinal direction. Comparison with finite element models shows that the rigid ring model of the tire is capable of describing the in-plane eigenmode shapes in the frequency range of 0–130 Hz. The well-known “brush model,” integrated into the tire model, is introduced to take into account the slide phenomena in the contact patch. The parameters of the model can be correlated with the physical properties of the tire so that designers can take advantage of such a correlation in the development of new tires in terms of time, cost, and performance. The technique used to determine the parameters of the model for some automobile tires include the direct measurements of some physical properties (mass, moment of inertia, stiffness) and a method of identification applied on the results from a dynamic test. The model is able to predict experimental data in terms of natural frequencies and relative dampings. Results from the application of this technique on two tires are reported.

Novel Technologıes and Nanotoxıcology of Medıcal Implants

2020 ◽  
Vol 16 ◽  
Author(s):  
Ramazan Akçan ◽  
Halit Canberk Aydogan ◽  
Mahmut Şerif Yıldırım ◽  
Burak Taştekin ◽  
Necdet Sağlam
Keyword(s):  
Human Health ◽  
Human Body ◽  
Diagnostic Procedures ◽  
Toxic Effects ◽  
Medical Implants ◽  
Healthcare Applications ◽  
Detailed Review ◽  
Novel Technologies ◽  
Technological Developments

Background/aim: Use of nanomaterials in the healthcare applications increases in parallel to technological developments. It is frequently utilized in diagnostic procedures, medications and in therapeutic implementations. Nanomaterials take place among key components of medical implants, which might be responsible for certain toxic effects on human health at nano-level. In this review, nanotoxicological effects, toxicity determination of nanobiomaterials used in human body and their effects on human health are discussed. Material and Method: A detailed review of related literature was performed and evaluated as per nanomaterials and medical implants. Results and Conclusion: The nanotoxic effects of the materials applied to human body and the determination of its toxicity are important. Determination of toxicity for each nanomaterial requires a detailed and multifactorial assessment considering the properties of these materials. There are limited studies in the literature regarding the toxic effects of nanomaterials used in medical implants. Although these implants are potentially biocompatible and biodegradable, it is highly important to discuss nanotoxicological characteristics of medical implant.

scholarly journals Characterizing the Effects of Explosive Ordnance Disposal Operations on the Human Body While Wearing Heavy Personal Protective Equipment

2021 ◽  
pp. 001872082199262
Author(s):  
Yi-Ning Wu ◽  
Adam Norton ◽  
Michael R. Zielinski ◽  
Pei-Chun Kao ◽  
Andrew Stanwicks ◽  
...  
Keyword(s):  
Human Body ◽  
Personal Protective Equipment ◽  
Evaluation Methodology ◽  
Protective Equipment ◽  
Physiological Measurement ◽  
Cognitive Stress ◽  
Explosive Ordnance Disposal ◽  
And Performance ◽  
Inspection Tasks ◽  
Muscle Activations

Objective To provide a comprehensive characterization of explosive ordnance disposal (EOD) personal protective equipment (PPE) by evaluating its effects on the human body, specifically the poses, tasks, and conditions under which EOD operations are performed. Background EOD PPE is designed to protect technicians from a blast. The required features of protection make EOD PPE heavy, bulky, poorly ventilated, and difficult to maneuver in. It is not clear how the EOD PPE wearer physiologically adapts to maintain physical and cognitive performance during EOD operations. Method Fourteen participants performed EOD operations including mobility and inspection tasks with and without EOD PPE. Physiological measurement and kinematic data recording were used to record human physiological responses and performance. Results All physiological measures were significantly higher during the mobility and the inspection tasks when EOD PPE was worn. Participants spent significantly more time to complete the mobility tasks, whereas mixed results were found in the inspection tasks. Higher back muscle activations were seen in participants who performed object manipulation while wearing EOD PPE. Conclusion EOD operations while wearing EOD PPE pose significant physical stress on the human body. The wearer’s mobility is impacted by EOD PPE, resulting in decreased speed and higher muscle activations. Application The testing and evaluation methodology in this study can be used to benchmark future EOD PPE designs. Identifying hazards posed by EOD PPE lays the groundwork for developing mitigation plans, such as exoskeletons, to reduce physical and cognitive stress caused by EOD PPE on the wearers without compromising their operational performance.

Dynamics and Performance of a Harmonically Excited Vertical Impact Damper

2008 ◽  
Vol 130 (2) ◽  
Author(s):  
Sanjiv Ramachandran ◽  
George Lesieutre
Keyword(s):  
Loss Factor ◽  
Vertical Direction ◽  
Theoretical Models ◽  
Coefficient Of Restitution ◽  
Numerical Continuation ◽  
Particle Impact ◽  
Impact Damper ◽  
High Loss ◽  
Wide Range ◽  
And Performance

Particle impact dampers (PIDs) have been shown to be effective in vibration damping. However, our understanding of such dampers is still limited, based on the theoretical models existing today. Predicting the performance of the PID is an important problem, which needs to be investigated more thoroughly. This research seeks to understand the dynamics of a PID as well as those parameters which govern its behavior. The system investigated is a particle impact damper with a ceiling, under the influence of gravity. The base is harmonically excited in the vertical direction. A two-dimensional discrete map is obtained, wherein the variables at one impact uniquely dictate the variables at the next impact. This map is solved using a numerical continuation procedure. Periodic impact motions and “irregular” motions are observed. The effects of various parameters such as the gap clearance, coefficient of restitution, and the base acceleration are analyzed. The dependence of the effective damping loss factor on these parameters is also studied. The loss factor results indicate peak damping for certain combinations of parameters. These combinations of parameters correspond to a region in parameter space where two-impacts-per-cycle motions are observed over a wide range of nondimensional base accelerations. The value of the nondimensional acceleration at which the onset of two-impacts-per-cycle solutions occurs depends on the nondimensional gap clearance and the coefficient of restitution. The range of nondimensional gap clearances over which two-impacts-per-cycle solutions are observed increases as the coefficient of restitution increases. In the regime of two-impacts-per-cycle solutions, the value of nondimensional base acceleration corresponding to onset of these solutions initially decreases and then increases with increasing nondimensional gap clearance. As the two-impacts-per-cycle solutions are associated with high loss factors that are relatively insensitive to changing conditions, they are of great interest to the designer.

Ride Comfort Evaluation of Horizontal Vibration in Tractor-Trailer Considering Human Body Motion of Driver

2013 ◽  
Author(s):  
Yuichiro Hirose ◽  
Mitsuru Enomoto ◽  
Takashi Sasaki ◽  
Eiichi Yasuda ◽  
Masatoshi Hada
Keyword(s):  
Human Body ◽  
Ride Comfort ◽  
Body Motion ◽  
Horizontal Vibration ◽  
Comfort Evaluation ◽  
Ride Comfort Evaluation

Happiness Index and Gadget Radiation Analysis on Yajna and Mantra Chanting Therapy in South Asian Continent

2021 ◽  
Vol 1 (1) ◽  
pp. 1-46
Author(s):  
Rohit Rastogi ◽  
Mamta Saxena ◽  
Mayank Gupta ◽  
Akshit Rajan Rastogi ◽  
Pradeep Kumar ◽  
...  
Keyword(s):  
Natural Disasters ◽  
Human Health ◽  
South Asian ◽  
Human Body ◽  
Human Life ◽  
Human Race ◽  
Asian Continent ◽  
Gender And Age ◽  
Body And Soul ◽  
Ancient Times

From ancient times, humans are striving for being healthy and to live with mental peace with family and society. In the previous centuries also, some manmade and mostly natural disasters have disturbed the pace of human life. There have been times when the whole human race has been in terror, danger, and utmost worry. The electrical gadgets also have made the human life comfortable, but also machines have dominated its consciousness. The stress, aggression, depression, and many more issues are also showing presence in all our lives. The chapter is a trial to establish the effect of yagna and mantra science over human calmness and its effect on human health irrespective to gender and age. The article also elaborates the effect of Sanskrit sound and mantra chanting on emission of radiations from electronic gadgets. It also presents the effect of spiritual practices on the human body and soul after the terror, stress, grief created due to COVID-19.

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