• 대한교통학회지
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• 제27권3호
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• pp.71-77
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• 2009

유비쿼터스 교통환경이 구현되면 기존 ITS 환경에서는 불가능하였던, 개별차량 위치, 속도 등 미세한 데이터 수집이 가능해 지며, V2V(Vehicle-to-Vehicle), V2I(Vehicle-to-Infra) 양방통신이 가능해 짐에 따라 개별차량 혹은 차량군 단위의 미세 제어가 가능해 진다. 이러한 유비쿼터스 교통 환경의 장점에 입각하여 교통류 안정성을 지표로 하는 연속류 정체예방관리 방안이 선행연구에서 제시된 바 있다. 본 연구에서는 유비쿼터스 교통환경에서 정체예방관리를 실현함에 있어 제기된 쟁점사항들에 대하여, VISSIM 시뮬레이션 실험결과에 입각하여 해답을 제시하였다. 교통류 안정성을 명시적으로 교통류 관리에 적용할 수 있도록, 유비쿼터스 교통환경에서 수집 가능한 차량군 길이와 간격으로 도출하였다. 또한 교통상황에 따라 차별화된 운영관리가 필요하다는 타당성을 도출하고, 교통상황 구분 및 상황별 운영관리 방안을 제시하였다. 마지막으로 이러한 관리를 수행하였을 때 어떠한 잠재적 이익이 있는가를 보여주었다. 본 연구 결과는, 제반 제약조건으로 말미암아 제한적인 시뮬레이션 실험을 통해 도출되었다. 그러나 유비쿼터스 교통환경에서 새로운 개념의 교통관리를 시행하는 데 있어 그 타당성은 보여줄 수 있었다고 판단된다. 향후 보다 포괄적인 현장실험을 통해 제반 결과들이 확정되어야 할 것이다.

• Journal of Mechanical Science and Technology
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• 제20권11호
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• pp.1898-1913
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• 2006

This paper deals with the design of a yaw rate controller based on gain-scheduled H$\infty$ optimal control, which is intended to maintain the lateral stability of a vehicle. Uncertain factors such as vehicle mass and cornering stiffness in the vehicle yaw rate dynamics naturally call for the robustness of the feedback controller and thus H$\infty$ optimization technique is applied to synthesize a controller with guaranteed robust stability and performance against the model uncertainty. In the implementation stage, the feed-forward yaw moment by driver's steer input is estimated by the disturbance observer in order to determine the accurate compensatory moment. Finally, HILS results indicate that the proposed yaw rate controller can satisfactorily improve the lateral stability of an automobile.

• Journal of Mechanical Science and Technology
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• 제18권11호
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• pp.1961-1968
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• 2004

The design of a reliable and failsafe control system requires that sensor failures be detected and identified within acceptable time limit so that system malfunction can be prevented. This paper presents a model-based approach to sensor fault detection with applications to vehicle stability control systems. The effectiveness of the proposed method is illustrated through test data-based evaluation. Vehicle test data-based evaluation results show that the proposed fault management scheme can be used for the design of a failsafe VSCs.

• 대한교통학회지
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• 제26권3호
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• pp.179-186
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• 2008

교통류의 안정성을 깨지 않음과 동시에 생산성을 저하시키지 않는 적절한 교통류 관리 방안이 필요하다. 지금까지 기존 지능형교통시스템(ITS: Intelligent Transportation System)에 의한 교통류관리에서는, 이러한 개념의 교통류 관리 방안을 명시적으로 다루지 못하였다. u-T(Ubiquitous Transportation) 시스템 환경 하에서, 개별차량 위치, 속도 등 미세한 데이터 수집이 가능해 지며, 이러한 개별차량 위치 데이터에 의해 기존 ITS 환경에서는 수집 불가능했던 밀도 산정이 가능해 진다. 또한 V2I(Vehicle-to-Infra), V2V (Vehicle- to-Vehicle) 등 양방통신이 가능해 짐에 따라 개별차량 혹은 차량군 단위의 미세 제어와 개별차량 단위의 미세 대응이 가능해 진다. 본 논문에서는, 이러한 u-T의 수집 데이터와 통신환경을 기반으로, 교통류가 불안정해 사고 잠재력이 커지고 결국 교통류가 와해되어 생산성이 저하되는 것을 예방하는 예방차원의 교통류 관리 방안을 제시하였다. 이것을 실현하기 위한 적정 속도, 적정 차두간격을 그린쉴드 모형에 기반하여 산정하였는데, 제반 교통류 모형을 비교 평가하여 적정 모형을 선택하는 연구도 향후 수행되어야 할 것으로 판단된다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2147-2152
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• 2011

This study of bimodal integration management system in conjunction with the tram and the tram cars bimodal integrated management system that occupies a part of the system to perform its role as a bimodal tram vehicle configuration, a device for the vehicle's infrastructure ryureul development and it is aimed to build on the vehicle. Bimodal tram vehicle infrastructure systems, internal and external information of the larger vehicles, and vehicles used to collect information for its own part and the integrated operations management center, or providing partial information from the station and collect/provide for the transfer of information to the communication part consists In this study, the core of these devices, the configuration of the vehicle infrastructure systems for the overall management and control of vehicles operating a computer's central processing device, vehicle infrastructure systems that make it manages and stores all jangchiryu Integrated Operations Management Center is reporting. In addition, seamless integration with operational management center for interactive communication in a vehicle mounted communications devices to maintain the best condition to manage. Current general traffic management system in a similar terminal device being used, but bimodal tram vehicles operating the computer of the vehicle operates the infrastructure to configure the devices around the one to configure the system in terms of step enhanced the active type, the operating terminal unit of inter active type. In this study, considering the future alignment of the accounting fee system, the expansion of the system reliability and stability around the activities that are underway.

• 한국산학기술학회논문지
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• 제14권9호
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• pp.4142-4148
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• 2013

경사지 과수의 효율적인 재배 및 관리를 위해 과수원 전용 고소 작업차량 사용이 늘어나고 있다. 이러한 이유로 작업자 안전을 위해 고소 작업차의 안정성에 대해 연구가 요구되고 있다. 본 연구는 경사지 흙길을 주행할 수 있는 4개의 바퀴와 2개의 직교 좌표계 적재함을 가진 과수원 차량의 안정성 평가에 대한 연구이다. 차량 메커니즘에 대한 다물체 동역학(MBD) 해석을 통하여 19.2, $34.6^{\circ}$의 좌우 및 상하 방향의 전복각을 계산할 수 있었다. 바퀴들의 주행 저항과 소요 동력을 결정하였다. 그리고 적재함 프레임의 유한요소해석(FEA)를 통하여 최대응력 146 MPa로 구조적으로 안정하다. 따라서 적재함을 가진 바퀴형 과수원 차량은 정적 및 동적 안정성을 가짐을 알 수 있었다.

• 디지털산업정보학회논문지
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• 제6권1호
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• pp.131-142
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• 2010

In this paper, we propose a web GPS based logistics vehicle control management system using MVC design patterns. The proposed system is designed by applying design patterns of object oriented modeling called mini-architecture to enhance reliability of software as well as promote stability of overall system design. In addition, we can get a position information by means of the GPS embedded in PDA and communicate between client and monitoring server using CDMA network so that the position of client can be identified directly by the map service. The system provides an moving object indexing technique which extends the existing TB-tree to manage and retrieve a transporting trajectory of logistics efficiently. Finally, with development of the logistics vehicle control service called WG-LOGICS system, we can verify the usefulness of our system which is able for monitoring a vehicle preparation, allocating registration, loading a burden, transfer path, and destination arrival in real world.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2005년도 춘계학술대회
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• pp.259-266
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• 2005

In this paper, we developed a vehicle condition monitoring system that checks vehicle conditions, and transmits and displays them to a driver for safety and effective maintenance. We used a CAN controller and transceiver to establish the CAN communication that has been used commonly inside an actual vehicle for the collection of vehicle's status information. To validate the operation of the developed system, we have confirmed the accuracy and stability of data transmission and reception of vehicle information.

• Journal of Power Electronics
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• 제11권4호
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• pp.479-489
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• 2011

The bidirectional dc-dc converter, being the interface between Energy Storage Element (ESE) and DC bus, is an essential component of the power management system for vehicle applications including electric vehicle (EV), hybrid electric vehicle (HEV), and fuel cell vehicle (FCV). In this paper, a novel multiphase bidirectional dc-dc converter interfacing with battery to supply and absorb the electric energy in the FCV system was studied with the help of real time digital simulator (RTDS). The mathematical models of fuel cell, battery and dc-dc converter were derived. A power management strategy was developed and first simulated in RTDS. A Power Hardware-In-the-Loop (PHIL) simulation using RTDS is then presented. The main challenge of this PHIL is the requirement for a highly dynamic bidirectional Simulation-Stimulation (Sim-Stim) interface. This paper describes three different interface algorithms. The closed-loop stability of the resulting PHIL system is analyzed in terms of time delay and sampling rate. A prototype bidirectional Sim-Stim interface is designed to implement the PHIL simulation.

• 한국기계가공학회지
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• 제19권8호
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• pp.64-72
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• 2020

In this study, a stability analysis was conducted through finite element analysis (FEA) of a simplified model of a fire ladder truck by changing the ascending angle, turning angle, and boundary conditions between the outrigger and the ground. The results of the analysis showed that decreasing the angle of the ladder car increases the moment due to the ladder weight, decreasing the safety factor despite being under the same load conditions. In the case of a rotating radius, the stability was found to vary depending on the boundary conditions. A comparative analysis in the future with these results and the experimental values from the actual fire ladder truck may determine the most appropriate boundary conditions based on the analysis program. It is expected to predict the risk of damage and rollover by assessing the stability of aerial ladder vehicles under different conditions.