• Journal of Biosystems Engineering
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• 제35권1호
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• pp.21-30
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• 2010

This study was performed to develop an active tire pressure control system that can adjust tire pressure to the optimum level according to traveling and working condition of agricultural tractor. For the development of active tire pressure control system, pneumatic supplier, solenoid valve block including pneumatic supply line, infinite rotation type pneumatic supplier with rotary joint unit, tire pressure transceiver module and control algorithm were developed. Also, tire simulator was developed. Using this tire simulator, the feasibility of each part constructing actual system was tested by checking the performance. The average communication success ratio was 98.3% between tire pressure transmitter and receiver module according to the various tire rotational speed and data receipt position of receiver module. The communication performance of the developed transmitter and receiver module was very stable in any condition. The tire pressure control system was accomplished by using the proportional control algorithm in this study. Also tire pressure control performance of developed control system was analyzed by using the tire simulator. As a result of control performance analysis to the developed system, the developed control system took 307 seconds to inflate agricultural tractor's tire from 50 kPa to 180 kPa. In opposite case, it took 210 seconds. Also it was able to control the tire pressure accurately under ${\pm}0.9%$ (FS) in any condition.

• 한국도로학회논문집
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• 제9권3호
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• pp.51-62
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• 2007

최근 들어 타이어/노면 소음을 저감하기 위한 다양한 포장공법들에 대한 연구가 진행되고 있다. 이러한 저소음 포장공법들을 개발하고자 하는 이유는 도로소음이 고속주행일 경우 도로노면과 타이어에서 발생하는 소음이 지배적이기 때문이다. 대부분의 저소음 포장공법의 핵심연구는 타이어/노면 소음이 노면의 미세조직 및 거시조직의 특성에 영향을 받는다는 점을 고려하여 표층 골재의 입도, 혹은 인위적인 노면조직에 대한 소음을 작게 발생하게 하는 것이다. 이러한 연구에서 어려운 점은 특정한 노면조직 혹은 포장공법에서의 타이어/노면 소음을 평가하기 위해 도로를 건설하고 차량을 주행시켜야 하기 때문에 비용과 시간의 제약을 받는다는 점이다. 따라서 이러한 난점을 극복하고, 다양한 노면조직에서의 소음을 저비용, 단시간에 평가하기 위하여 본 연구에서는 타이어/노면 소음재현장비를 개발하였고, 무타이닝 및 횡방향타이닝 포장에 대하여 타이어/노면 소음을 재현 및 측정을 통하여 개발한 장비의 신뢰성을 검증하였다.

• Journal of Mechanical Science and Technology
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• 제18권9호
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• pp.1493-1499
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• 2004

This paper describes the speckle shearing interferometry, a non-destructive optical method, for quantitative estimation of void defect and monitoring separation defect inside of a pneumatic tire. Previous shearing interferometry has not supplied quantitative result of inside defect, due to effective factors. In the study, factors related to the details of an inside defect are classified and optimized with pipeline simulator. The size and the shape of defect can be estimated accurately to find a critical point and also is closely related with shearing direction. The technique is applied for quantitative estimation of defects inside of a pneumatic tire. The actual traveling tire is monitored to reveal the cause of separation and the starting points. And also unknown void defects on tread are inspected and the size and shape of defects are estimated which has good agreement with the result of visual inspection.

• 제어로봇시스템학회논문지
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• 제16권6호
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• pp.566-571
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• 2010

EPS (Electric Power Steering) is important device for improving vehicle's dynamics and static performances. This paper deals with simulator design for C-EPS (Colum type-EPS), development assist and returnability control algorithm. First, C-EPS system model was simply designed because EPS system is complex control system that has many unknown variables. These parameters were simplified through assumptions. Second, C-EPS simulator was designed for development of control algorithm. This simulator has SAS (Steering Angle Sensor), dual torque sensor, dual load cell for measuring rack force, dual linear actuator for generating tire force and Data Acquisition System. Using this simulator, control methods ware tested. Third, control algorithm was designed for torque assist and returnability. Assist torque map and returnability torque map were found by lots of simulation test. These torque maps were tuned for EPS actuator control. The simulation result was compared with non-EPS system result. In this research, the C-EPS simulator was designed for development of control algorithm about torque assistant and returnability. Using this simulator, control algorithm was improved.

• 실천공학교육논문지
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• 제15권1호
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• pp.53-61
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• 2023

근현대 자동차 신산업 분야에서 가장 큰 핵심 과제는 2035년 EU 연합의 배출가스 0%를 목적으로 하는 친환경 차량 개발에 있으며, 이에 따라 전기자동차로 산업이 급변하는 시대에서 EV전기차에 대한 교육훈련이 절실한 상황인데, 본 연구에서는 기존 내연기관차와 동일하게 사용하는 Chassis Platform(Body, Tire 등)을 제외한 핵심적인 EV 파워트레인 시스템 시뮬레이터를 개발함으로써, 기계공학적, 전기공학적, 전자공학적 활용 등 EV 파워트레인 시스템을 이해하고 본 과정을 통해 공학적, 융합적 개발 능력을 키우는 매체로 활용하고자 한다.

• 한국도로학회논문집
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• 제12권3호
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• pp.79-85
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• 2010

본 논문은 골재부착력(aggregate retention) 평가를 통해서 칩실(chip seal)에서 사용되는 롤러 종류의 기초적인 연구 결과를 설명하고 있다. 입도 78M의 화강암 골재와 CRS-2 이멀젼(emulsion)을 사용하여 single layer 칩실 테스트 구간을 시공하였으며, 3개의 다른 롤러 종류를 사용하였다. 사용된 롤러 종류는 pneumatic tire roller, steel wheel roller, and combination roller를 사용하였다. 세 종류의 롤러의 성능을 효과적으로 연구하기 위해서는 시공현장으로부터 직접 테스트용 시편을 얻는 것이 매우 중요하기 때문에, 노스캐롤라이나 주, Bailey에 있는 New Sandy Hill Church Road에서 테스트 구간 설정하고 일반적인 노스캐롤라이나 주의 칩실시공 절차에 준하여 시공을 실시하였다. 테스트 구간에서 제작된 시편들을 실험실로 옮겨서 골재부착력(aggregate retention) 성능평가를 실시하였다. 골재의 부착력을 평가하기 위해서 flip-over test(FOT), Vialit test, and the third-scale Model Mobile Loading Simulator (MMLS3) 시험방법들을 채택하였다. 세 가지의 시험결과들과 시험시공 현장에서 관측된 육안조사를 통해서 다음과 같은 롤러 종류와 순서를 추천하게 되었다. pneumatic tire roller 와 combination roller를 함께 사용하며 처음에 pneumatic tire roller가 다짐을 한 뒤에 그 뒤를 combination roller가 다짐하는 순서로 다짐작업을 함으로써 칩실의 성능이 향상 되리라 사료된다.

• 대한기계학회논문집A
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• 제24권9호
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• pp.2228-2234
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• 2000

Steering of the vehicles on a slippery highway is a difficult task for most passenger car drivers. The steering vehicles on slippery roads tend to slide outward with less lateral forces than on nor mal roads. When the drivers notice that their vehicles on a slippery highway start to depart from the cornering lane, most of them make a sudden steering and/or braking, which in turn may induce spin-out and instability on their vehicles. In this paper, an active steering control method is proposed such that the vehicles in slippery roads are steered as if they are driven on the normal roads. In the proposed method, the estimated lateral forces acting on the steering tires are compared with the reference values and the difference is compensated by the active steering method. A fuzzy logic controller is designed for this purpose and evaluated on a steering Hardware-In-the-Loop Simulation (HILS) system. Steering performance results on the slippery curved and sinus roads demonstrate the effectiveness of the proposed controller. This method can be realized with the steer-by-wire concept and is promising as an active safety technology.

• 드라이브 ㆍ 컨트롤
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• 제16권4호
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• pp.48-55
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• 2019

The Electronic Stability Program (ESP), a system that improves vehicle safety, also known as YMC (Yaw Motion Controller) or VDC (Vehicle Dynamics Control), is a system that operates in unstable or sudden driving and braking situations. Developing conditions such as unstable or sudden driving and braking situations in a vehicle are very dangerous unless you are an experienced professional driver. Additionally, many repetitive tests are required to collect reliable data, and there are many variables to consider such as changes in the weather, road surface, and tire condition. To overcome this problem, in this paper, hardware and control software such as the ESP controller, vehicle engine, ABS, and TCS module, composed of three control zones, are modeled using MATLAB/SIMULINK, and the vehicle, climate, and road surface. Various environmental variables such as the driving course were modeled and studied for the real-time ESP real-time simulator that can be repeatedly tested under the same conditions.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1126-1131
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• 2007

This paper presents unified chassis control (UCC) to improve the vehicle lateral stability. The unified chassis control implies combined control of active front steering (AFS), electronic stability control (ESC) and continuous damping control (CDC). A direct yaw moment controller based on a 2-D bicycle model is designed by using sliding mode control law. A direct roll moment controller based on a 2-D roll model is designed. The computed direct yaw moment and the direct roll moment are generated by AFS, ESP and CDC control modules respectively. A control authority of the AFS and the ESC is determined by tire slip angle. Computer simulation is conducted to evaluate the proposed integrated chassis controller by using the Matlab, simulink and the validated vehicle simulator. From the simulation results, it is shown that the proposed unified chassis control can provide with improved performance over the modular chassis control.

• 대한기계학회논문집A
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• 제31권2호
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• pp.145-151
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• 2007

Impulsive excitation on vehicle produces shock-type vibration on the seat, which has major frequencies and damping ratios dependent on the characteristics of the suspension, the tire, the seat cushion and so on. The response of single degree of freedom model to a half-sine force input was considered as simple shock-type vibration signal. Quasi-apparent-mass for fifteen subjects was measured with the shock-type vibration generated on a rigid seat mounted on the simulator, so its nonlinearity was apparently found over 6.3 Hz according to the difference of magnitude of the shock.