• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.623-628
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• 2001

The styling of passenger car wheels and their effect on vehicle appearance has increased in importance in recent years. The wheel designer has been given the task of insuring that a wheel design meets its engineering objectives without affecting the styling theme. The wheel and tire system is considered as a vehicle component whose dynamic modal information of the tire/wheel system are employed in the modal synthesis model of the vehicle. The Vibration characteristics of a passenger car wheel play an important role to judge a ride comfortability and quality for a passenger car. In this paper, the vibration characteristics of a AI-alloy and steel wheel for passenger car are studied. Natural frequency, damping and mode shape are determined experimentally by frequency response function method. Results show that wheel material property, size and design are parameter for shift of natural frequency and damping.

• 한국자동차공학회논문집
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• 제20권1호
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• pp.61-67
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• 2012

The in-wheel motor used in green car was designed and constructed for an electric direct-drive traction system. It is difficult to connect cooling water piping because the in-wheel motor is located within the wheel structure. In the air cooling structure for the in-wheel motor, a outer surface on the housing is provided with cooling grooves to increase the heat transfer area. In this study, we carried out the analysis on the fluid flow and thermal characteristics of the in-wheel motor under the effects of motor speed and heat generation. In order to check the problem of heat release, the analysis has been performed using conjugate heat transfer (conduction and convection). As a result, flow fields and temperature distribution inside the in-wheel motor were obtained for base speed condition (1250 rpm) and maximum speed condition (5000 rpm). Also, the thermo-flow characteristics analysis of in-wheel motor for vehicles was performed in consideration of ram air effect. Therefore, we checked the feasibility of the air cooling for the housing geometry having cooling grooves and investigated the cooling performance enhancement.

• 유공압시스템학회논문집
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• 제4권1호
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• pp.13-17
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• 2007

The brake gain adaptive wheel slip controller for a vehicle is designed in this paper. The brake gain from braking pressure to braking torque defined by friction coefficient, friction area and effective friction radius is estimated by the adaptive law based on the wheel slip dynamics. And the wheel slip controller is designed based on the estimated brake gain. The robustness of the designed controller is analyzed using Lyapunov function and the convergence of brake gain is verified. Proposed wheel slip controller is verified via CarSim simulation with two kinds of desired wheel slip ratio.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.404-410
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• 2002

In this study, we have analyzed the optimum control of wheel for coach car in maintenance process to grasp the problem relating to this coach's wheel exchanged. So, these problems brought about decrement maintenance cost. This study were deliberated to solve problems concerning maintenance process of wheel exchanged and wheel specification in rolling stock workshops of KNR. Here, we describe some results.

• 디자인학연구
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• 제16권3호
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• pp.371-380
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• 2003

현대 소비자들은 좀더 감각적이고, 정서적 만족감을 제공하는 제품을 기대하고 있으며, 이에 감성공학이란 전문적인 지식들을 자동차 디자인에 응용할 필요성이 대두되게 된 것이다. 자동차의 경우 개성 있는 나만의 차를 갖고 싶어하는 욕구로 자동차를 꾸미는 데에 많은 투자를 하면서 휠 디자인이 중요시되고 있다. 이에 본 연구에서는 새로운 디자인 방향 모색으로 감성 공학적 분석 방법을 통하여, 소비자들의 자동차 휠 디자인에 대한 이미지를 파악하고, 소비자의 요구와 감성에 따른 자동차 휠 디자인을 분석하였다. 그 결과, 'harmonious', 'fresh'와 'strong'의 이미지가 자동차 휠 디자인을 대표하며, 'harmonious' 이미지로는 스포크 타입, 'fresh'의 이미지는 메쉬 타입, 'strong'의 이미지는 디쉬 타입의 자동차 휠 디자인으로 나타났다. 따라서 자동차 휠의 디자인 개발에 소비자의 감성을 기반으로 한 감성 공학적 디자인 접근을 함으로써 소비자에게 만족시킬 수 있는 디자인 방향 제시를 가능케 하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1642-1645
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• 2008

It is said that the effect in wheels of freight car varies with the type of freight, the condition of operation, the braking device, and the type of bogie. The hardness of open wagon, gondola car, propylene car, covered freight car, container car and hopper car has been measured according to the mileage through this research. As a result, the wheel with more mileages after shaving off the wheel tread has a higher hardness than the others in the case of same type of car.

• 전기학회논문지
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• 제67권3호
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• pp.440-447
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• 2018

Double parking is very common in a parking lot where there is not sufficient parking space. When we double-park a car, we leave transmission gear in neutral position and release the emergency brake so that the double-parked car can be moved just by pushing it. However, moving a double-parked car by pushing is very hard and dangerous especially for the old and the weak. So, we propose an omni-directional mobile robot for moving a double-parked car easily and safely. The developed omni-directional mobile robot moves a double-parked car by rotating a wheel of a double-parked car. It has two specially designed rollers to rotate a wheel of a double-parked car and is designed so that the height of the robot is very low to be able to enter beneath a double-parked car. It can move a double-parked car safely by detecting obstacles in the way with five ultrasonic sensors. We verified by several experiments that the developed omni-directional mobile robot can be used to move a double-parked car easily and safely.

• 한국자동차공학회논문집
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• 제8권2호
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• pp.129-137
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• 2000

In the prototype stage of a car developing program, the efficiency of trouble shooting is an important factor to be considered. Structural modifications by the design sensitivity analysis are applied to a steering wheel system for improving the idle vibration of the prototype passenger car. For the design sensitivity analysis, the experimental modal analysis for the steering system attached to a body-in-white is fulfilled and the modal parameters extracted from the experimental data are used to predict the effect of structural modification, The design sensitivity results rank the locations to be reinforced in terms of frequency variation. The modification of steering system according to the sensitivity analysis results shifted the resonant frequency of the system effectively. In addition, the idle test of the car after the structural modifications f steering system shows that the proposed method can reduce vibration of the steering wheel efficiently.

• 한국디자인학회:학술대회논문집
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• 한국디자인학회 2003년도 가을학술발표대회
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• pp.16-17
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• 2003

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1152-1157
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• 2005

This paper is concerned with the construction of an improved sliding mode control for the active suspension system of a one-wheel car model subject to the excitation from a road profile. The active control is composed of the equivalent and the switching controls where an improved sliding surface is proposed. The active control force is generated by operating a pneumatic actuator due to the control signal that constructed by measuring the state variables of the car model and by estimating the excitation from the road profile using the VSS observer. The experimental result indicates that the proposed active suspension system is relatively effective in the vibration suppression of the car model.