• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.3
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• pp.147-159
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• 2023

In order to make autonomous vehicles more trustworthy, it is necessary to focus on the users of autonomous vehicles. By evaluating the preferences for driving behaviors of autonomous vehicles, we aim to identify driving behaviors that increase the acceptance of users in autonomous vehicles. We implemented two driving behaviors, aggressive and cautious, in a driving simulator and allowed users to experience them. Biometric data was collected during the ride, and pre- and post-riding surveys were conducted. Subjects were categorized into two groups based on their driving habits and analyzed against the collected biometric data. Both aggressive and cautious driving subjects preferred the cautious driving behavior of autonomous vehicles.

• Proceedings of the KSR Conference
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• 2003.10b
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• pp.423-428
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• 2003

본 논문은 열차 곡선부 노선에서 발생하는 진동크기의 예측을 위한 것으로, 곡선부를 주행하는 틸팅차량에 의해 발생하는 진동크기를 수치해석적으로 예측한 결과이다. 곡선부를 주행하는 틸팅차량에 의한 진동의 특징으로, 진동의 방향성분을 들 수 있다. 진동의 방향성분은 직선 구간에서는 수직성분이 월등히 우세하나, 곡선구간에서는 수평성분이 크게 증가한다. 틸팅차량의 경우, 일반열차에 비해 곡선구간에서의 높은 속도로 인해 수평성분이 크게 발생한다. 따라서 틸팅차량의 주행에 의한 인근 지역에서의 진동환경을 파악하기 위해서는 수직성분 뿐 아니라 수평성분의 정확한 파악도 필요하다. 이러한 진동의 방향성분은 근거리 또는 원거리 영역에 따라 달라져, 이의 파악을 위한 연구가 필요하다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.146-153
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• 2003

본 논문은 열차 곡선부 노선에서 발생하는 진동크기의 예측을 위한 것으로, 곡선부를 주행하는 틸팅 차량에 의해 발생하는 진동크기를 수치해석적으로 예측한 결과이다. 곡선부를 주행하는 틸팅차량에 의한 진동의 특징으로, 진동의 방향성분을 들 수 있다. 진동의 방향성분은 직선 구간에서는 수직성분이 월등히 우세하나, 곡선구간에서는 수평성분이 크게 증가한다. 틸팅차량의 경우, 일반열차에 비해 곡선 구간에서의 높은 속도로 인해 수평성분이 크게 발생한다 따라서 틸팅차량의 주행에 의한 인근 지역에서의 진동환경을 파악하기 위해서는 수직성분 뿐 아니라 수평성분의 정확한 파악도 필요하다. 이러한 진동의 방향성분은 근거리 또는 원거리 영역에 파라 달라져, 이의 파악을 위한 연구가 필요하다.

• Journal of IKEEE
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• v.25 no.1
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• pp.148-155
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• 2021

As robot technology advances, research on the driving system of mobile robots is actively being conducted. The driving system of a mobile robot configured based on two-wheels and four-wheels has an advantage in unidirectional driving such as a straight line, but has disadvantages in turning direction and rotating in place. A ball robot using a ball as a wheel has an advantage in omnidirectional movement, but due to its structurally unstable characteristics, balancing control to maintain attitude and driving control for movement are required. By estimating the position from an encoder attached to the motor, conventional ball robots have a limitation, which causes the accumulation of errors during driving control. In this study, a driving control system was proposed that estimates the position coordinates of a ball robot through image processing and uses it for driving control. A driving control system including an image processing unit, a communication unit, a display unit, and a control unit for estimating the position of the ball robot was designed and manufactured. Through the driving control experiment applying the driving control system of the ball robot, it was confirmed that the ball robot was controlled within the error range of ±50.3mm in the x-axis direction and ±53.9mm in the y-axis direction without accumulating errors.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.6
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• pp.731-738
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• 2013

This paper describes a fault-tolerant driving control strategy for an independent steer-by-wire system in sixwheel-drive/six-wheel-steering vehicles. An algorithm has been designed to realize vehicle maneuverability that is as close as possible to that of non-faulty vehicles by inducing high slip ratio of the wheel through a faulty steer-by-wire system in order to reduce the lateral tire force, which is resistant to the yaw motion. Considering the transition of the longitudinal tire force of a wheel with a faulty steer-by-wire component, the longitudinal tire forces are optimally distributed to the other wheels. Fault-tolerant driving performance has been investigated via computer simulations. Simulation studies show that the proposed algorithm can significantly improve the maneuverability of a vehicle with a faulty steer-by-wire system as compared to the optimal traction distribution method.

• Journal of the Korean Society for Railway
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• v.18 no.2
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• pp.117-126
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• 2015

The development of railway roadbed for 600km/h train speed level is very difficult because unpredictable static and dynamic interaction occurs between the ultra-high speed train and the infrastructure. Especially, an earthwork-bridge transition zone is a section in which influential factors react, such as bearing capacity, compression, settlement, drainage, and track irregularity; these interactions can include complicated dynamic interaction. Therefore, if static and dynamic stability are secured in transition zones, it is possible to develop roadbeds for ultra-high speed railways. In the present paper, design parameters for transition reinforcement applied to present railway design criteria are analytically examined for ultra-high speed usage on a preferential basis. Design parameters are the presence of reinforcing materials, geometric shape, stiffness of materials, and so on. Analysis is focused on the deformation response of the track and running stability at ultra-high speed.

• Journal of Korean Society of Transportation
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• v.22 no.7 s.78
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• pp.139-146
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• 2004

Road design should be conformed to the expectancy of drivers. The alignment such as long tangent followed by the sharp horizontal curve should be avoided for the road design consistency. Currently, operating speed profile model is generally used to check the consistency of the successive road alignments. In this model, the hypothesis about the drivers' behaviour on the long tangent followed by the sharp horizontal curve is also included. This study compares the hypothesized drivers' behaviour in the existing operating speed profile model with the actual drivers' behaviour observed at the two lane rural roads. In addition to this, comparison between the acceleration for the vehicles approaching and departing horizontal curves suggested by the foreign research and the value observed at this study was made, From this study, it was concluded that the hypothesis in the existing model was well representing the actual drivers' behaviour. The deceleration for vehicles approaching the horizontal curves was ranged $0.39{\sim}1.06m/s^2$ with the average of $0.66m/s^2$. The average acceleration for the vehicles departing horizontal curves was $0.22m/s^2$.

• Journal of the Korean Society for Railway
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• v.13 no.5
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• pp.509-515
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• 2010

Primary function of a transition curve is to accomplish gradual transition from the straight to circular curve, so that curvature changes from zero to a finite value. The transition curve enhances the running safety and ride comfort of the vehicle in curve. There are a couple of transition curve such as clothoid, cubic parabola and cosinusoidal curve, etc. In this study, running behaviors of cubic parabola and cosinusoidal curve were investigated and compared by numerical analysis result using VAMPIRE program. Ride comforts for an individual transition curve were evaluated for each transition curve and running behavior and safety were also evaluated to compare the capacity of transition curves.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1994.10a
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• pp.46-51
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• 1994

자동차용 MCP(Multi Changer Player)는 조용하고 깨끗한 음악을 감상하고 싶어하는 소비자들에게 큰 호응을 얻고 있다. 그러나 주행중에 외력이 자동차용 MCP 데크를 통하여 클렘핑부(Clamping부 : 이하 방진부라 함)에 전달되어 방진부에 진동이 발생할 수 있다. 이때 방진부에 장착되어 있는 CD(Compact Disc)의 음재생에 영향을 줄 수 있다. 따라서 본 연구에서는 자동차용 MCP 데크 메카니즘의 중요 구성 부분인 방진부를 설계 및 실험 해석에 의해 진동 저감 대책을 세움으로써 기초 자료를 확보하고 제품의 성능을 향상시키고자 한다. 자동차용 MCP 데크에 장착된 방진부의 진동 저감 문제를 해결하기 위해 먼저 다음과 같은 사항이 방진부에 미치는 영향도를 알아본다. 1) 아이들링(Idling) 중일때의 자동차의 특성과 주행중일때의 자동차의 특성 및 노면 외란이 진장부에 미치는 영향도를 파악한다. 2) CD가 클램핌되어 있을 때의 CD의 모드를 해석해 본다. 그리고 방진재로 사용된 스프링의 설계 및 방진 고무의 물성치 변화에 따른 방진부의 특성변화를 실험에 의해 해석하여 적절한 방진재를 선정한다. 또한 결정된 방진재를 사용한 MCP의 음비(Sound Skip) 특성을 측정해본다.

• International Journal of Highway Engineering
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• v.10 no.3
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• pp.97-107
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• 2008

I study for design criteria and research about Interchange diverging area of express highway and freeway, the most recent, at interchange diversion of express highway and freeway, design criteria and researches are focus on safety guarantee a point of view movement dynamics of vehicle and road geometric as to transition section, deceleration section, curve radius, nose section, outflow angle etc, that is, design criteria and research of Interchange diverging area have not consider a point of view movement dynamics of vehicle and road geometric and driver, so that I will be focus characteristic of runing speed on trasion curve. and I will consider vehicle running speed characteristics and study problem of Interchange diverging area design criteria. For this study, First, analysis meaning about theory of now design criteria, Second, look at vehicle running speed and traffic accident characteristics of Interchange diverging area, Third, propose new deceleration transition curve design method get along vehicle running speed characteristics of Interchange diverging area. new deceleration transition curve design method put out new outcoums, that is, I definite cause to safety new deceleration transition curve design method better than pressently, used design criteria of Interchange diverging area, especially, deceleration transition curve design criteria produced good result in the running speed 50km/h, 40km/h, that is inertia better than inertia of present used design criteria. and deceleration transition curve is extended better than present transition curve criteria, so that new deceleration transition curve design method safety is good better than the past method safety.