• 시스템엔지니어링학술지
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• 제15권2호
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• pp.1-8
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• 2019

Autonomous vehicles operated in the rough terrain environment must satisfy various technical requirements in order to improve the speed. Therefore, in order to design and implement a technical architecture that satisfies the requirements for speed improvement of autonomous vehicles, it is necessary to consider the overall technology of hardware and software to be mounted. In this study, the technical architecture of the autonomous vehicle operating in the rough terrain environment is presented. In order to realize high speed driving in pavement driving environment and other environment, it should be designed to improve the fast and accurate recognition performance and collect high quality database. and it should be determined the correct running speed from the running ability analysis and the frictional force estimation on the running road. We also improved synchronization performance by providing precise navigation information(time) to each hardware and software.

• Wind and Structures
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• 제17권2호
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• pp.203-225
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• 2013

An analysis framework for vehicle-bridge dynamic interaction system under turbulent wind is proposed based on the relevant theory of wind engineering and dynamics. Considering the fluctuating properties of wind field, the stochastic wind velocity time history is simulated by the Auto-Regressive method in terms of power spectral density function of wind field. The bridge is represented by three-dimensional finite element model and the vehicle by a multi-rigid-body system connected by springs and dashpots. The detailed calculation formulas of unsteady aerodynamic forces on bridge and vehicle are derived. In addition, the form selection of wind barriers, which are applied as the windbreak measures of newly-built railways in northwest China, is studied based on the suggested evaluation index, and the suitable values about height and porosity rate of wind barriers are studied. By taking a multi-span simply-supported box-girder bridge as a case study, the dynamic response of the bridge and the running safety indices of the train traveling on the bridge with and without wind barriers are calculated. The limit values of train speed with respect to different wind velocities are proposed according to the allowance values in the design code.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.1483-1484
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• 2010

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.491-491
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• 2000

In this paper, we report the results about the rotational control count on DC motor to drive the mobile vehicle as a first step of the research for the realization of the mobile vehicle with the artificial brain. First of all, we introduce the configuration of the mobile vehicle. This mobile vehicle has one CCD camera driven by a rear wheel. Secondly we show the control methods. This research is adopted the various controls. Finally we report the experimental methods and results and we describe the conclusion of this research.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.133-138
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• 2004

Domestic freight car holding amount is possessing much amount than other vehicle model about 14,000. Problem is happening in bogie device of cast steel structure because is structure that there are many wear departments. Therefore, the KNR is restricting running speed of empty car by 70km/h low. In this research, presented speed elevation way as dynamic characteristic analysis result that use ADAMS and confirm running safety by main line test.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 춘계학술대회 논문집
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• pp.143-150
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• 2000

Like conventional railways, improving running performance of vehicle in curve is more effective than improving maximum speed to reduce traveling time. But some vehicles have problems concerning running performance in cure because of insufficient study for our conventional railway characteristics. So, these problems brought about increasement of maintenance cost. This study was started to deliberate several plans to solve problems concerning running performance in curve. Some modifications of primary suspension and tests were carried out to improve curve negotiation. Here, we describe some results.

• 한국지능시스템학회논문지
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• 제18권6호
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• pp.797-807
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• 2008

본 논문은 복잡한 도로 영상에서 차량 검출의 효율성을 높이기 위해 체인코드를 이용한 차선의 검출로부터 도로 영역을 찾아 차량이 존재하는 차량 영역의 추출 기법을 제안한다 먼저, 복잡한 도로 영상에서 정확한 차선을 검출하기 위해 체인코드를 이용하여 에지 화소들간의 연결성을 고려한다. 주행 차량의 방향과 일치하는 차선을 검출한 후, 중앙의 차선으로부터 차도의 폭과 차선의 소실점을 찾아 인접하는 차도를 찾는다. 마지막으로 주행 차선과 인접 차선을 포함하는 도로 영역 내에 차량의 에지 정보를 이용하여 차량이 존재하는 차량 영역을 추출한다 따라서, 제안하는 차량 영역의 추출 기법은 복잡한 배경을 갖는 도로 영상에서 차량의 검출율을 높이고 추출된 차량 영역에 한정할 수 있기 때문에 차량을 검출하는데 매우 효율적이다. 본 논문은 제안하는 차량 영역의 추출 기법의 우수성을 복잡한 도로 영상에서 차량 검출율의 실험을 통해 검증하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.3187-3194
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• 2011

Vehicle dynamic behavior should be investigated to establish the track irregularity criteria because they have an impact on vehicle dynamic behavior. The tilting train which have been developed in Korea will be operated on the conventional line. Therefore, it should be checked that the track irregularity criteria of conventional line is still available for the new vehicle. In this paper, the influence of alignment on running behavior and safety for tilting train was instigated by numerical analysis. The wavelength and amplitude of alignment were considered in scenario of this numerical analysis. This research is based on just numerical analysis and the final result which include measurement will be published in the future.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1937-1942
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• 2010

Vehicle dynamic behavior should be investigated to establish the track irregularity criteria because they have an impact on vehicle dynamic behavior. The tilting train which have been developed in Korea will be operated on the conventional line. Therefore, it should be checked that the track irregularity criteria of conventional line is still available for the new vehicle. In this paper, the influence of vertical alignment on running behavior and safety for tilting train was instigated by numerical analysis. The wavelength and amplitude of vertical alignment were considered in scenario of this numerical analysis. This research is based on just numerical analysis and the final result which include measurement will be published in the future.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.71-77
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• 2007

The surface of railway wheel tread in wheel-rail system can not be free from wear because of various circumstance such as railway condition, maintenance condition, weather condition, characteristics of wheel surface's geometrical shape, and vehicle suspension's structural characteristics etc. Therefore, the research on wear reduction and maintenance method are very important to ensure the safety of railway vehicle, to improve car comfort and to decrease maintenance cost. In this study, the wear rates of railway wheel have been periodically measured in terms of the running distance of Electrical Multiple Unit which have been currently operated and the microstructure transformation of wheel tread using replication method have been performed. The results show that the relations between the flange wear and tread microstructure are depended on running distance and it will supply basic data on wheel maintenance.