• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.855-860
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• 2001

In this study, the improvement work to reduce the steering wheel vibration of a forklift truck is performed. The forklift truck newly developed possesses a trans-axle type power train to achieve a compact and low-price design. The forklift truck is directly subjected to a high-level engine vibration through hard mounted trans-axle housing. The engine vibration shakes the whole system of the forklift truck, and then a high level local vibration of steering wheel could not be avoided. As the results, the vibration source and path mechanisms are experimentally identified and then an improvement design is proposed to minimize the steering wheel vibration.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.1197-1204
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• 2004

The metropolitan cities and operation companies of urban transit railway are driving to construct the LRT(light rail transit) system because of the advantage of construction cost and environmental serviceability. This study suggests the optimal design method of steel box girder considering dynamic characteristics of LRT with rubber wheel. The behavior and design constraints are formulated based on the structural design criteria for LRT. Genetic algorithm is applied to the minimum weight design of structural system. A typical example is solved to illustrate the applicability of the proposed minimization algorithm. From the results of application example, the optimum design of steel box girder is successfully accomplished. Therefore, this system can act as a consultant to assist novice designers in the design of steel box girder for LRT with rubber wheel.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.5
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• pp.551-558
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• 2011

To analyze the effect of wear of wheel profile on the running stability of rolling-stock, theoretical and experimental studies were conducted on the profiles used in conventional lines. In experiment using 1/5 scale model to verify the results of the theoretical analysis, the test results of the critical speed for worn wheel profile samples show similar trend. In case of the conical type wheel profile(Profile 40), the equivalent conicity is increased with flange wear. But in case of the arc type wheel profile(Profile 20h), the equivalent conicity is decreased with flange wear. And the critical speed of the bogie was inverse proportion to the equivalent conicity. It is shown that the variation of the critical speed with the wheel wear could be changed according to the design concept and wear pattern of wheel profile. Results of the theoretical and experimental studies are discussed here.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.05a
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• pp.278-282
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• 2003

There is a strong industrial demands for the development of light-vehicle to improve fuel efficiency. It is more effective to reduce weight of the parts directly driven by an automobile engine. So the saving in weight of wheels which is operated by an automobile engine improve fuel efficiency more than other parts. There are many step of sheet metal forming in fabricating automotive wheel, so that it is difficult to design process and tools of multi-stage stamping. Traditionally, design process and tools have depended on the experience of skilled workers and it has done by trial and error methods. However, it needs too much costs and time. Taguchi methods has an advantage of the number of required experiments and reliability compared with trial and error method. In this study, Taguchi methods and response surface methods are applied to design process and tools of automotive wheel. As a result, the principal variables are selected and process conditions are optimized.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.3-8
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• 2001

This study is an investigation for the ADS optimum design by using FEA. We write out program which express ADS perfectly and reduce the required time for correcting of model to the minimum in solution and manufacture result. We complete algorithm which can plan optimum forming of model by feedback error information in CAE. Then we correct model by feedback date obtaining in solution process, repeat course following stress solution again and do modeling rachet wheel for optimum forming. That is our aim. In rachet wheel, greatest equivalence stress originates in key groove corner and KS standard is proved the design for security.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.1287-1288
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• 2012

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.641-644
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• 2003

The running safety of the rolling stock depends on the design characteristics and the contact condition between wheel and railway. In this study, it is analyzed how equivalent conicity of wheel tread or its characteristics has influence on the running safety.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.6
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• pp.732-737
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• 2011

The planetary gear reducer becomes more and more widely used in machine industries. The planetary gear reducer has a significant role to transmit power to wheel & tire module in the In-wheel system. Thus, the planetary gear reducer should have strong stiffness and durability. In this paper, the contact and bending stresses at the tooth of the planetary gear reducer are analyzed using MASTA, a commercial gear design and analysis software. Stress distribution at the tooth face of the sun, planetary and annulus gears are obtained using the finite element method. The design modification is performed using the response surface method. The usefulness of the design modification and optimization method presented in this paper is verified by comparing the maximum stresses of the original and optimized planetary gear tooth.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.8
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• pp.992-999
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• 2011

The recent power add-on drive wheelchairs (PADWs) provide greater physical activity, are easier to transport, and may be an excellent alternative for the typical manual or electric wheelchairs. The development of in-wheel motor for a PADW is the principal issues. In this paper, design, implementation, and testing of the permanent magnet synchronous motor (PMSM) for a PADW are presented. To design output power and torque of the motor, the equation of motion has been investigated. The design parameters were calculated and the dimension and shape of the motor which was limited by the In-wheel mechanism of the PADW were done by applying FEM and optimal design technique. The prototype of the motor mentioned above was fabricated with precise machining and assembling. Then the motor tested on dynamometer and the measured results of the motor were verified by comparing the design results. The fabricated motor was 80 mm in length with a diameter of 110 mm and small enough to be attached the driving unit of the PADW.

• Korean Journal of Computational Design and Engineering
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• v.19 no.4
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• pp.332-339
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• 2014

This paper presents on the development of wheel-terrain interaction device using low-priced sensors, which will be used to predict the drawbar pull and optimal slip of off-road vehicle in real time. The essential variables obtained in the device to predict the mobility of vehicles are determined based on semi-empirical model describing the wheel-terrain interaction. Using the developed device, the experiments about the wheel-terrain interaction were performed on the soil of the Jumunjin standard sand, which yielded dynamic weight, motor driving torque, drawbar pull, and sinkage with respect to wheel slip ratio. Finally, the repeatability of the measured data are verified through repeating the experiments three times on the same condition.