• Journal of the Korean Society of Industry Convergence
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• v.6 no.3
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• pp.261-266
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• 2003

이 논문에서는 반능동 진동 흡수기를 통합 시트/섀시 현가 장치에 확대, 적용하여 그 성능을 조사하였다. 통함 현가시스템의 성능분석을 위해 집중 인체질량과 함께 실험적으로 입증된 한 비선형 시트 쿠션 모델을 도입하였다. 또한 3 자유도 시트/섀시 현가시스템의 효과적인 진동제어를 위해 리아푸노브 바이스테이트 제어법칙을 사용하였다. 시뮬레이션결과 반능동 통합 현가장치는 시트 쿠션 모델과 관계없이 운전자의 승차감과 관련 있는 시트의 절대가속도 크기와 시트쿠션의 시트 트랙에 대한 상대변위를 상당히 감소시킬 수 있음을 알 수 있었다. 그러나, 주로 사용되어온 선형 쿠션 모델을 사용한 경우보다 비선형쿠션 모델을 사용한 경우의 제진성능이 약간 저조함을 알 수 있었다. 따라서, 자동차 시트 설계시 성능분석을 위해서는 실제의(비선형의) 시트 쿠션 특성을 적용해야 함을 알 수 있다.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2002.05a
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• pp.164-170
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• 2002

현재 농업용 장비들은 특성상 사용자에게 심한 양의 진동을 가하고 있다. 이는 사용자에게 나쁜 승차감을 주고 또한 장시간 운전시에는 건강에도 좋지 않은 영향을 줄 수 있다. 본 연구에서는 농업용 트랙터에서 사용자에게 전달되는 진동의 양을 측정하여 사용자가 느끼는 승차감을 정량적으로 측정하고 또한 건강에 미칠 수 있는 영향에 대해 평가해 보았다. 실험은 포장도로와 농로 그리고 논갈기 작업시에 인체에 전달되는 12축의 진동을 측정하였고, 또한 트랙터에 사용되는 서스펜션 시트의 특성을 보기 위해 시트 아래의 수직방향 진동을 측정하였다 실험에 참가한 피실험자는 모두 현재 트랙터를 사용하고 있는 4명을 대상으로 하였다 실험 결과 현재의 트랙터는 사용자에게 좋지 않은 승차감을 주고 있으며 건강에도 좋지 않은 환경을 제공하고 있음을 볼 수 있었다. 이러한 환경을 개선하기 위해서는 서스펜션 시트의 설계가 중요하게 되는데 보다 좋은 승차감을 제공하기 위해서는 인간이 민감하게 느끼고 또 트랙터에서 많은 양이 나타나는 주파수 대역의 진동을 저감하기 위한 설계가 필요하다고 할 수 있다.

• Journal of the Korean Society for Railway
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• v.18 no.3
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• pp.194-202
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• 2015

In this paper, dynamic modeling with viscoelastic properties of a human body resting on a seat is presented to quantitatively analyze ride quality of passengers exposed to vertical vibrations. In describing the motions of a seated body, a 5 degree-of-freedom multibody model from the literature is investigated. The viscoelastic characteristics of seats used in railway vehicles are mathematically formulated with nonlinear stiffness characteristics and convolution integrals representing time delay terms. Transfer functions for the floor input are investigated and it is found that these are different in accordance with the input magnitude due to nonlinear characteristics of the seat. Measured floor input at the railway vehicle is used to analyze realistic human vibration characteristics. Frequency weighted RMS acceleration values are calculated and the effects of the seat design parameters on the frequency weighted RMS acceleration values are presented.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.138-145
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• 2005

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.5689-5695
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• 2012

In this study, vibration properties of seat and human body are analyzed through test and numerical analysis methods by taking into account the viscoelastic characteristics of polyurethane foam as seat material which is applied for vehicle. These viscoelastic characteristics which show nonlinear and quasi-static behavior are obtained by compression test. In addition, the viscous elastic property of polyurethane foam is modelled mathematically by using convolution integral and nonlinear stiffness model. In order to analyze the performance on ride comfort of seat, vertical vibration model is established by using dynamic model of seat and vertical vibration model of human body at ISO5982, and so the related motion equations are derived. A numerical analysis simulation is applied by using the nonlinear motion equation with Runge-Kutta integral method. The dynamic responses of seat and human body on the input of vibration acceleration measured at the floor of the railway vehicle are examined. The variation of the index value at ride comfort on seat design parameters is analyzed and the methodology on seat design is suggested.

• Journal of the Korea Convergence Society
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• v.9 no.8
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• pp.155-160
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• 2018

Automotive seat is a part to supply the convenience and safety of driver at driving. Recently, the seat has the role to protect driver from the outside impact or vibration and give the convenience except such a usage as chair. The design on structural function of the seat frame is important like the impact safety and durability. In this study, the seat is designed by adding one hollow rod to the part of seat back frame in order to enhance the structural safety and durability. This study was carried out by using CATIA and ANSYS as the design and analysis programs. As this study result through the structural and vibrational analyses, model 4 was seen to have the durability more superior than the other models. By utilizing this result, it is thought to be the useful material at designing the automotive seat frame with durability. It is possible to be grafted onto the convergence technique at the automotive seat frame and show the esthetic sense.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.8
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• pp.626-631
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• 2002

A modified equation for the evaluation of discomfort of a seated human body exposed to differential vibration at the seat and the floor was proposed in this paper. Through the review and analysis of the preceding studies, effect of phase difference between the seat and the floor vibration on discomfort were quantitatively identified. The phase effect was shown to be governed by not only phase difference between the two vibrations but both their frequency and the magnitude, which means the present equation for the evaluation of perceptual amount of vibration provided by ISO 2631-1 should be modified. The proposed equation was developed such that the correction function was multiplied to the present equation. The correction function consisted of three parts, each of them represented the effect by phase difference, frequency and vibration magnitude on discomfort respectively.

• Proceedings of the KAIS Fall Conference
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• 2012.05b
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• pp.565-568
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• 2012

승차감이나 안전에 관련된 부분 중 하나인 자동차 시트는 차량 주행시 전달되는 충격이나 진동을 적절하게 흡수하여 승객에게 안락성을 제공한다. 또한 이러한 여건을 만족시키면서 승객의 안전을 보장하는 충분한 강성과 강도를 가져야 한다. 자동차 시트는 2가지의 모델로 설계를 하고 구조 해석을 하였다. 그 결과, 시트 백프레임의 모델 (b)가 (a)보다 적은 변형량과 피로 수명을 보였고. 모델의 중앙에 해당되는 허리부분에서 가장 많은 변형량과 파손 가능성을 보였다. 고유진동수를 적용한 진동해석에서, 모델(a)의 경우는 모델의 바깥쪽에서 안쪽으로 변형이 되었고, 모델(b)의 경우는 모델의 안쪽에서 바깥쪽으로 변형이 되었다. 전반적으로 모든 면에서 모델(b)가 (a)보다 구조적으로 안전하다고 사료된다.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.4
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• pp.93-99
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• 2002

Ride comfort, one of the most important performances of a car, is affected by vibration, noise, dynamic movement, and ergonomic factors. Among these factors, ride comfort vibration is heavily affected by the seat system, tire, suspension, and body structure. In this study, vibration characteristics of seat, tire, suspension, and body structure are analyzed. The vibration transfer function from the road input to the human body is also investigated.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.8 no.3
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• pp.151-160
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• 2014

In this study, the effect of the automotive haptic-seat technology which can transmit the driving information by the vibro-stimulus from the seat was investigated to overcome previous system's limitation relied on the visual and audial method and to help handicap driving. A prototype haptic seat cover with 30 coin-type motors and driver module were developed for this sake. In an experiment of seat vibration stimulation being performed under virtual driving situation by targeting the elderly aged over 65 years old, average score of test subjects for total vibration recognition was 3.5/4 points and recognition rate of 87.5% was represented. In addition, a result that all the test subjects totally recognized overspeed warning signal of 4 times was represented. As a result of statistical analysis for vibration recognition score by each group depending on TMT score, a significant difference was not found and a result that tactile function of which vibration is recognized even by the aged whose visual, perceptional function is declined showed an equal ability was obtained.. In this study it was shown that the seat vibration stimulus could be used to transfer the old drivers' information while driving.