CEVAP YÜZEYİ YAKLAŞIMI İLE TAŞIT KOLTUĞU SONLU ELEMAN MODELİNİN GÜNCELLENMESİ

Year 2019, Volume: 24 Issue: 3, 273 - 290, 31.12.2019

Hakan Gokdag , Yılmaz Arısoy Osman Kopmaz

https://doi.org/10.17482/uumfd.541340

Abstract

Ana sanayi firmaları üretimini talep ettikleri taşıt koltuklarının belirli şartnamelere uygun olmasını
isterler. İmalatçı firma bu durumda koltuğun prototipini üretip birtakım değiştirme ve iyileştirmelerle
teknik şartları sağlamaya çalışabilir. Fakat bu yol pahalı ve zaman alıcıdır. Bu durumda alternatif yöntem
koltuğun sonlu eleman modelini geliştirmek ve üzerinde parametrik çalıştırmalar gerçekleştirmektir. Bu
çalışmada öncelikle bir ticari araç koltuğunun iskelet aksamına eklenen sünger, kılıf, sırt tahtası gibi
katmanların koltuğun ileri-geri ve yanal doğrultudaki modal parametrelere etkisi deneysel olarak
incelenmiştir. Buradan elde edilen sonuçlara göre koltuk iskeleti sonlu eleman modeline katmanlar çeşitli
kütle ve katılık parametreleriyle eklenmiştir. Daha sonra sonlu eleman modelinin gerçek koltuk modeliyle
uyumlu olması için bu parametrelerin uygun değerleri cevap yüzeyi yaklaşımı ile belirlenmiştir. Ayrıca
bu yöntemle, ilgili katmanların hangilerinin daha etkili olduğu da görülmüştür. Sonuç olarak, sonlu
eleman modeli ile elde edilen temel frekansların her iki doğrultu için deneysel frekanslarla uyumlu
olduğu, özellikle ileri-geri harekette frekans cevabı fonksiyonu genliklerinin de birbirine oldukça yakın
olduğu görülmüştür.

Keywords

Taşıt koltuğu, Sonlu Eleman, Titreşim, Cevap yüzeyi, Model Güncelleme

Model Updating of a Vehicle Seat Finite Element Model by the Response Surface Method

Abstract

Vehicle manufacturers demand vehicle seats to be in accordance with certain specifications.
Therefore, a seat manufacturer company may produce a prototype of the seat so that the specifications
may be satisfied by various modifications and improvements. However, this is expensive and time
consuming approach. As an alternative, finite element model of the seat may be developed so that some
parametric studies may be performed before manufacturing. In this work, first, experimental studies are
implemented to study the influence of layers added to the metal structure such as foam, seat cover,
backrest board to seat’s foreaft and lateral modal properties. Outcomes of these studies are considered to
define layers as additional mass and stiffness components in the software environment. Later, response
surface methodology is utilized to determine suitable values of the layer components so as to match the
finite element model with the real one. Besides, which layer parameters are dominant in the model is
figured out by this method. Finally, it is concluded the finite element model updating is achieved by the
response surface method, since the experimental and the computational frequencies for both foreaft and
lateral frequencies are in good agreement, and especially the foreaft frequency response function
amplitudes of the finite element and real model are compatible.

Keywords

Vehicle seat, Finite element, Vibration, Response surface, Model updating

References

• Marwala, T (2010) Finite-Element Model Updating Using Computational Intelligence Techniques: Application to Structural Dynamics, Springer-Verlag, London. doi: 10.1007/978-1-84996-323-7.
• Wang, Q. ve Deng, X. (1999). Damage detection with spatial wavelets. International Journal of Solids and Structures, 36, 3443-3468. doi: 10.1016/S0020-7683(98)00152-8.
• Sehgal, S. ve Kumar, H. (2014) Structural dynamic finite element model updating using Derringers Function: A Novel Technique. Wseas Transactions On Applied And Theoretical Mechanics, 9, 11-26. (http://www.wseas.org/multimedia/journals/mechanics/2014/a045711-133.pdf).
• Ren, W.X. ve Chen, H.B. (2010). Finite element model updating in structural dynamics by using the response surface method. Engineering Structures, 32, 2455-2465. doi: 10.1016/j.engstruct.2010.04.019
• Shan, D, Li, Q., Khan, I. ve Zhou, X. (2015) A novel finite element model updating method based on substructure and response surface model. Engineering Structures, 103, 147 doi: 10.1016/j.engstruct.2015.09.006
• Jninkwan, A, ve Singh, J. (2014). Simulation of moment deflection test on driver seat of car using finite element analysis. International Journal of Science and Research, 3(7), 299-303. https://www.ijsr.net/archive/v3i7/MDIwMTQ5OTI=.pdf
• Grujicic, M, Pandurangan, B., Arakere, G. Bell, W.C., He, T. ve Xie, X. (2009). Seat-cushion and soft-tissue material modeling and a finite element investigation of the seating comfort passenger-vehicle occupants. Materials Design, 30, 4273-4285. https://doi.org/10.1016/j.matdes.2009.04.028.
• Liu, C., Qiu, Y., Griffin, M.J. (2013). Finite element modelling of human-seat interactions: vertical in-line and fore-and-aft cross-axis apparent mass when sitting on a rigid seat without brackets and exposed to vertical vibration. Ergonomics, 58(7), 1207-1219. doi: 10.1080/00140139.2015.1005164
• Zhang, X., Qiu, Y., Griffin, M. (2014). Developing a simplified finite element model of a car seat with occupant for predicting vibration transmissibility in the vertical direction. Ergonomics, 58(7), 1220-1231. doi: 10.1080/00140139.2015.1005165
• Myers, R.H., Montgomery, D.C. ve Andersen-Cook, C.M. (2009). Response Surface Methodology: Process and Product Optimization Using Designed Experiments, John Wiley & Sons, New Jersey.
• Fang, S-E. ve Perera, R. (2011). Damage identification by response surface based model updating using D-optimal design. Mechanical Systems and Signal Processing, 25, 717-733. doi:10.1016/j.ymssp.2010.07.007.
• Mukhopadhyay, T., Dey, T.K., Chowdhury, R.. ve Chakrabarti, A. (2015). Structural damage identification using response surface-based multi-objective optimization: A comparative study, Arab J Sci Eng, 40,1027-1044. doi: 10.1007/s13369-015-1591-3.
• Banerjee, A., Panigrahi, B. ve Pohit, G. .(2015). Crack modelling and detection in Timoshenko FGM beam under transverse vibration using frequency contour and response surface model with GA, Nondestructive Testing and Evaluation, doi: 10.1080/10589759.2015.1071812.
• He, J. ve Fu, Z. (2001). Modal Analysis, Woburn, MA: Butterworth-Heinemann.
• Efe, H ve Çağatay, K. (2011). Çeşitli masif ağaç malzemelerin bazı fiziksel ve mekanik özelliklerinin belirlenmesi, Politeknik Dergisi, 14, 55-61. doi: 10.2339/2007.10.3.303-311.
• http://kisi.deu.edu.tr/burak.felekoglu/17.ahsap.pdf, Erişim Tarihi: 23.10.2018, Konu: Ahşap malzemelerin teknik özellikleri
• Parsopoulos, K. E. ve Vrahatis, M. N. (2010). Particle Swarm Optimization and Intelligence: Advances and Applications, IGI Global, Hershey, PA, USA.