• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.559-560
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• 2012

• 한국정밀공학회지
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• 제30권1호
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• pp.47-52
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• 2013

In order to operate a search and rescue robot in hazardous area, the robot requires high mobility and adaptable locomotion for moving in unpredictable environments. In this paper, we propose the deformable soft wheel robot that can produce three kinds of driving modes; caterpillar driving mode, normal wheel driving mode, legged-wheel driving mode. The robot changes its driving mode as it faces the various obstacles such as a small gap, stairs etc. Soft film and composite materials are used for fabrication of deformable wheel structure and Shape Memory Alloy (SMA) coil spring actuators are attached on the structure as an artificial muscle. Film lamination and an composite manufacturing process is introduced and the robot design is required to be modified and compromised to applying the manufacturing process. The prototype is developed and tested for verifying feasibility of the deformable wheel locomotion.

• 한국철도학회논문집
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• 제13권1호
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• pp.16-22
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• 2010

다양한 철도차량 동역학 해석 프로그램들은 장단점을 가지고 있다. 이러한 프로그램들은 가선계를 표현할 수 있는 대변형체를 나타낼 수 없는 한계를 가지고 있다. 본 연구에서는 철도차량의 동역학 해석을 할 수 있는 프로그램을 개발하였다. 이 프로그램은 강체, 유연체, 대변형체에 대한 해석을 수행하고 상용프로그램과의 비교를 통하여 신뢰성을 확보하였다. 또한 가선계를 대변형체로 고려하였고, 강체와 대변형체를 연결하는 미끄럼 조인트를 추가하였다. 여기에 휠-레일 접촉모듈을 추가하여 철도차량의 동역학 해석이 가능한 프로그램을 개발하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.793-794
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• 2011

• 제어로봇시스템학회논문지
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• 제16권11호
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• pp.1060-1067
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• 2010

In this paper, we present a new type of spherical robot having two arms. This robot, called KisBot, mechanically consists of three parts, a wheel-shaped body and two rotating semi-spheres. In side of each semi-sphere, there exists an arm which is designed based on slider-crank mechanism for space efficiency. KisBot has hybrid types of driving mode: rolling and wheeling. In the rolling mode, the robot folds its arms through inside of itself and uses them as pendulum, then the robot works like a pendulum-driven robot. In the wheeling mode, two arms are extended from inside of the robot and are contacted to the ground, then the robot works like a one-wheel car. The Robot arms can be used as a brake during rolling mode and add friction to the robot for climbing a slope during wheeling mode. We developed a remote controlled type robot for experiment. It contains two DC motors which are located in the center of each semi-sphere for main propulsion, two RC motors for each arm operation, speed controllers for each semi-sphere, batteries for main power source, and other mechanical components. Experiments for the rolling and wheeling mode verify the hybrid driving ability and efficiency of the our proposed spherical robot.

• 한국자동차공학회논문집
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• 제14권2호
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• pp.23-31
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• 2006

Tolerance analysis of auto body requires the consideration of its compliance because of potentially significant deformation during the spot-weld assembly process. In this paper, a relatively recent method for such analyses is briefly introduced as one can find in the literature. In this method, it is important to take into account of the covariance between the sources of variation as they are closely located, which is the case in most auto body assembly. However, it is often impossible to know such covariance, for example, when a new car is being developed. Therefore, a mechanics-based method is proposed in this paper to estimate the covariance among the sources of variation by finite element analyses and simple statistical computations. The proposed method is illustrated by applying it to a three-dimensional model of real front wheel housing.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.473-479
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• 2009

Dynamic analysis is necessary for the High-Speed Railway vehicle which aims to run on max 400km/h. Especially, dynamic simulation using CAE(Computer Aided Engineering) can help to reduce the time of development of the High-Speed Railway vehicles. Also, it helps to reduce prices and improve the quality such as safety, stability and ride. There are many dynamic software for a railway vehicle, such as Vampire and ADAMS-Rail. There are limitations for each software and difficulties to analyze overall dynamics for entire railway system. To overcome these limitations, in this study, a program which can simulate entire railway vehicles was developed. This program is easy to use because it was developed using C++, which is object-oriented programming language. In addition, the basic platform for the development of dynamic solver is prepared using the nodal, modal coordinate system with a wheel-rail contact module. Rigid, flexible and large deformable body systems can be modeled by a user according to the characteristic of a desired system. Its reliability is verified by comparison with a commercial analysis program.

• Journal of Astronomy and Space Sciences
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• 제38권4호
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• pp.237-250
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• 2021

A rover is a planetary surface exploration device designed to move across the ground on a planet or a planetary-like body. Exploration rovers are increasingly becoming a vital part of the search for scientific evidence and discoveries on a planetary satellite of the Sun, such as the Moon or Mars. Reliable behavior and predictable locomotion of a rover is important. Understanding soil behavior and its interaction with rover wheels-the terramechanics-is of great importance in rover exploration performance. Up to now, many researchers have adopted Bekker's semiempirical model to predict rover wheelsoil interaction, which is based on the assumption that soil is deformable when a pressure is applied to it. Despite this basic assumption of the model, the pressure-sinkage relation is not fully understood, and it continues to present challenges for rover designers. This article presents a new pressure-sinkage model based on dimensional analysis (DA) and results of bevameter tests. DA was applied to the test results in order to propose a new pressure-sinkage model by reducing physical quantitative parameters. As part of the work, a new bevameter was designed and built so that it could be successfully used to obtain a proper pressure-sinkage relation of Korean Lunar Soil Simulant (KLS-1). The new pressure-sinkage model was constructed by using three different sizes of flat plate diameters of the bevameter. The newly proposed model was compared successfully with other models for validation purposes.