Natural Frequency Analysis of Automotive Seating System by using fem software
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Fig4 shows that the two materials are used for the analysis of seat assembly. The cast iron is used for the arm rest component and steel is used for other component of seat assembly for avoiding resonance of seat. 
Fig. 5 : Natural frequency of Steel and cast iron material for seat Fig5 show that the second natural frequency of seat. We observe that the maximum value of the displacement is taking place at the arm rest component. This is due to the fact that vibration is going to act on this part of the seat. These are observed in persons exposed to WBV over a long period of time and are associated with the resonant movement of the hand. The frequency of the vibration for this particular mode of the seat is 22.22Hz.
Table6- Comparison of human body parts and seat components for both steel and cast iron material combination. A seat design modification improves the vibration performance of the seat in vibration surroundings of the vehicle so change the material of arm rest of seat. The changing seat frame stiffness then change the natural frequency of the seat assembly beyond the principal vibration frequency of the automotive vehicle. 
Plot1 : Effect of material on natural frequency of seat The engine is to run for any continuous length of time for the avoidance of placing any resonance at or near human body part and speeds. Which indicates possible resonances and thus potentially hazardously high levels of vibration can be moved by changing either the running speed or the natural frequencies. The designer generally has more flexibility in the change the natural frequency parameter of component and so the first choice for vibration control is resonance avoidance by changing the material of critical components of seat so that their natural frequencies do not coincide with human body parts and engine order lines at running speeds.
The model of new seating system for vibration response is developed and it analyzed by simulation for purpose of minimizes human body responses. In this analysis, finite element advance is used to analyze the vibration feature of seating system by determining the natural frequency for steel and cast iron material. The analysis result shows that individual steel and cast iron material are showing resonant frequency in hand rest of seat so we change the material of the arm rest. On the basis of FE analysis result, we can conclude that both steel and cast iron material combination would be a better choice for seat assembly to avoid the resonance phenomenon so the natural frequency of seat component must be separated from frequency of the human body parts. IX. REFERENCES [1] Fazlollahtabar, Hamed. "A subjective framework for seat comfort based on a heuristic multi criteria decision making technique and anthropometry." ELSEVIER, 2010. [2] Kaya, I. Karen & N. "A design tool to evaluate the vehicle ride comfort characteristics: modeling, physical testing, and analysis." Springer, 2011. [3] Kolich, Mike. "A conceptual framework proposed to formalize the scientific investigation of automobile seat comfort." ELSEVIER,2007. [4] Lange, M.M. Verver and R. de. "aspects of seat modelling for seating comfort analysis." ELSEVIER, 2004. [5] Pankoke, A. Siefer and S. "Virtual optimisation of car passenger seats: Simulation of static and dynamic effects on drivers’ seating comfort." Max-Planck-Strasse Hochberg, Bavaria, Germany., 2007. [6] Rosen, Jacob, and Jacob Rosen. "Modeling the Human Body/Seat System in a Vibration Environment." Department of Electrical Engineering,University of Washington.
ISSN (Print): 2321-5747, Volume-1, Issue-2, 2013 Directory: journal ijmer -> pdf pdf -> International Journal on Mechanical Engineering and Robotics (ijmer) Download 420.47 Kb. Share with your friends:
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