• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.12
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• pp.1541-1546
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• 2013

The stress concentration of lock-claws, which are one of the important parts for pneumatic fitting for a flexible tube connection, was investigated by finite element simulation. In this study, the generation of the local plastic deformation was predicted when the tube was hooked up to a pneumatic fitting in order to disperse the stress concentration, and design optimization was carried out using the Taguchi method. For the optimization, the outer width, bending angle, and inner radius of the lock-claws are used as main variables. As a result, their respective contribution ratios are revealed as 81.3%, 10.9%, and 1.5%. The ratio of the total stress distribution was improved by 4% compared with the initial design of the lock-claws.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.838-842
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• 2017

The thruster valve, which is one of the key components applied to the mono-propellant system for the satellite, has a circular plate spring structure. It can be designed as a structure that does not have positional deformation and particles by friction and repetitive motion. In this study, finite element analysis and verification were performed by setting the width of the circular plate spring as a design parameter with the material, thickness and radius of the circular plate spring as fixed variables. The linearity of the spring constant is shown by the graph that is spring force with displacement. It is confirmed that the optimization design of the circular plate spring is possible by the spring force tendency according to the total area of circular plate spring.

• Journal of the Korea Convergence Society
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• v.11 no.12
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• pp.155-159
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• 2020

In this study, the structural analyses were performed on the number of leaf springs in large truck. The deformations were small for all four models. The maximum stress of model A was found to be the largest, and that of model D was the smallest. Model A was seen about 1.87 times larger than model D and about 1.52 times larger than model B. The maximum stresses of models C and D were seen to be less. In terms of the effect to reinforce one more overlapping spring, The effect of the enhancement of the strength of model D was shown to be small by comparing with model C. Therefore, model C with three overlapping springs is thought to be efficient in design and good in strength. The structural strength of leaf spring can be evaluated by applying this study result to the leaf spring at large truck. And it is seen that the result can be the design of the leaf spring with durability at large truck and the aesthetic convergence.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.6
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• pp.771-780
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• 2010

This paper describes the design process of a six-component force/torque (F/T) sensor. The new six-component F/T sensor having leaf spring ends has been developed using a cross beam structure as the basic sensing element. Fundamental strain analysis of both ends fixed beam having a leaf spring structure is performed by finite element analysis. In order to obtain similar output sensing strains from the six component loads and minimize coupling strains, the optimal location of strain gages is determined and the strain gages are connected so that the bridge circuits with four strain gages would be balanced. Using leaf spring ends instead of rigid fixed ends, remarkable increment in output sensing strain can be achieved for two component forces. Several modifications in design result in a similar sensing strain of approximately $400\;{\mu}m/m$ for the six-component forces and moments, and a reduced coupling strain of $0\;{\mu}m/m$ between the forces and moments.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.4
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• pp.22-31
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• 2005

The purpose of this study is to design a flexural structure that has a function of pan and tilt for an artificial eyeball. The artificial eyeball system has a function of image stabilization, which compensate panning and tilting vibration of the body on which the artificial eyeball is attached. The target closed loop control bandwidth is 50Hz, so the mechanical resonance frequency is required to be more than the control bandwidth, which is a tough design problem because of a big mass of camera and actuator. In this study, the design process including the selection of the principal parameters by numerical analysis with ANSYS will be described, as well as the design results and frequency response.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.3
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• pp.379-385
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• 2013

The tires, suspension type, and steering system can all cause pulling during braking. Among these, a drag link steering system and leaf-type suspension system are significant causes of vehicle pulling. In this study, the pulling problem is analyzed using the vehicle analysis program "ADAMS/CAR." The drag link and leaf spring behavior is analyzed to find the key reason for pulling. After this, the optimization program "Visual DOC" is used with "ADAMS/CAR" to find a steering link connection point to reduce pulling. After conducting this simulation, K&C (kinematic & compliance) test simulation with a modified connection point is conducted to determine whether the vehicle performance improves. Through a full braking simulation, it is verified that the pulling distance is reduced at braking.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.2 s.95
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• pp.232-238
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• 2005

This paper proposed an optimal plate spring design for the optical pickup suspension. This method requires an analytic solution of plate spring suspension and it can be obtained by Castigliano's theorem and moment equilibrium. However, it is very complex due to the many design variables coupled and some constraints such as pitching angle in focusing motion caused by the characteristics of plate spring. Because of the complex formulation of the analytical solution that is used as the design objective, the genetic algorithm is used to find the optimal design value satisfying design constraints.

• Aerospace Engineering and Technology
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• v.3 no.2
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• pp.191-196
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• 2004

Most of studies for landing gear have been performed to analyze the shock absorbing characteristics of oleo-pneumatic struts. But it is not easy to solve the dynamic specific properties of spring type composite landing gear using a present method. The shock absorbing abilities of oleo-pneumatic landing gear strut are under influence of the internal design method on the strut rather than the landing gear structure itself. Unlike oleo type, spring type composite strut absorbs the shock with structural strength and dynamic characteristics of the strut's material and shape. The tests and analysis for the shock absorbing rate and dynamic behavior of the spring type composite fixed landing gear for 4 seats small aircraft, have been performed using landing gear drop test rig.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.169-174
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• 1998

두께는 일정하나 너비가 균일하게 변하는 판스프링들로 구성된 너비감소 판형 홀다운 스프링 집합체에 대한 탄성강성도 특성해석을 수행하였다. 국산 경수로 핵연료의 홀다운스프링 집합체와 동일한 설계공간내에 있도록 고안한 여러 종류의 너비감소 판형 홀다운 스프링 집합체 시편에 대한 탄성강성도를 해석적으로 평가하였고 특성시험을 수행하였다 또한 실제 시험 결과들을 잘 예측할 수 있도록 Euler 보 이론과 변형률 에너지법에 근거한 탄성강성도 평가방법을 보정하였다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.2
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• pp.61-67
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• 2001

Development of a barrier system for floating debris at river is introduced. The system is to prevent pollution of coastal water caused by marine debris which originates from land. The system consists of harrier boom, mooring system and boom winder. The harrier boom, which is self-inflatable with circular band spring, guides floating debris to a collecting conveyer system. Design parameters of the harrier system were reviewed and its design criteria were established. Based on the established design criteria, a pilot harrier system was built and tested at Tanchon branch of the Han river. It is proved that the suggested system is very efficient to collect floating debris at river.