• 한국산학기술학회논문지
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• 제14권1호
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• pp.57-62
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• 2013

카트 차체에는 현가장치와 차동장치가 존재하지 않으므로 카트주행 중 발생하는 프레임의 변형은 탄성변형으로 인한 주행성능과 프레임의 피로수명에 영향을 미친다. 선회주행 시 비틀림 변형에 의한 카트의 거동은 이 두 가지 변형에 결정적 원인을 제공한다. 이러한 곡선구간에서 카트의 동적 거동을 분석하기 위하여 GPS를 이용하여 차량의 궤적을 추적하고 카트 프레임 강에 작용하는 비틀림 응력을 측정하였다. 레저와 레이싱 카트 프레임의 기계적 성질을 파악하기 위해 재질 분석과 인장시험을 실시하여 각 프레임의 재료 특성을 분석하였다. 비틀림 응력집중과 프레임 비틀림은 프레임 해석을 통해 조사되었다. 또한 주행 분석 장치를 이용하여 레저와 레이싱 카트를 각 조건별로 실차실험을 수행하였고, 이를 통해 곡선구간에서 카트의 주행거동을 분석하였다. 선회주행 시 차량에 원심력에 의한 하중이동의 현상이 발생했으며, 이로 인해 카트 프레임 강에 비틀림 응력이 발생하였다.

• 한국자동차공학회논문집
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• 제21권3호
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• pp.105-112
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• 2013

In this paper, EV (Electric Vehicle) and ICE (Internal Combustion Engine) vehicle simulators are developed to compare maximum driving range of EV and ICE vehicle according to different driving patterns. And, simulations are performed for fourteen constant velocity cases (20, 30, 40, ${\ldots}$, 150 km/h) and four different driving cycles. From the simulation results of constant velocity, it is found that the decreasing rate of maximum driving range for EV is larger than the one for ICE as both the vehicle velocity and the driving power increase. It is because the battery efficiency of EV decreases as both the velocity and the driving power increase, whereas the engine and transmission efficiencies of ICE vehicle increase. From the results of four driving cycle simulation, the maximum driving range of EV is shown to decrease by 50% if the average driving power of driving cycle increases from 10 to 20kW. It is because the battery efficiency decreases as the driving power increases. In contrast, the maximum driving range of ICE vehicle also increases as the average driving power of driving cycle increases. It is because the engine and transmission efficiencies also increase as the driving power increases.

• 대한산업공학회지
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• 제38권1호
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• pp.41-45
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• 2012

Until now, most studies of foot moving or driving posture have been performed under laboratory driving conditions. But there are many different things between actual driving conditions and laboratory driving conditions because, in laboratory conditions, it is hard to consider vehicle's noise, vibration and people's psychology state while driving. Thus this study is performed through actual driving conditions. And while driving test, we recorded driver's foots with 2 cameras to investigate foots(left and right) heel point and how human foots move to control the three pedals : accel, brake and footrest.. Through driving test, the results of this study show that the position of driver's heel point isn't related to stature and tends to be generalized.

• 자동차안전학회지
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• 제14권4호
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• pp.60-69
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• 2022

Recently, the importance of simulation validation in a virtual environment for autonomous driving system validation is increasing. At the same time, interest in the advancement of the virtual driving environment is also increasing. To develop autonomous driving technology, a simulation environment similar to the real-world environment is needed. For this reason, not only the road model is configured in the virtual driving environment, but also the driving environment configuration that includes the surrounding environments -traffic, object, etc- is necessary. In this article, FMTC, which is a test bed for autonomous vehicles, is implemented in a virtual environment and advanced to form a virtual driving environment similar to that of real FMTC. In addition, the similarity of the virtual driving environment is verified through comparative analysis with the real FMTC.

• 한국ITS학회 논문지
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• 제22권5호
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• pp.182-199
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• 2023

정부는 2021년부터 다부처 연구개발사업으로 자율주행기술개발혁신사업을 추진해오고 있다. 해당 연구개발사업에서 개발되는 자율주행차와 서비스 기술은 추후 선정된 리빙랩 도시를 대상으로 일반인들에게 제공한다는 계획이다. 특히 서비스분야는 해당 서비스별 목적과 특성에 따라 안전하고 안정적인 서비스가 가능한 공간적 범위와 운행구간을 선정하는 것이 중요하다. 본 연구에서는 향후 Level 4 수준의 자율주행서비스 제공 구역 설정 방법론을 개발하기 위한 기초 연구로서 기존 공개된 논문 및 관련 문헌조사를 통해 Level 4 수준의 자율주행서비스를 위한 정적인 ODD 구성요소를 재분류하고, 자율주행의 안전성에 미치는 공간적인 영향 요인에 대하여 Level 3 자율주행차 실제 주행데이터 및 공간정보분석 기법을 활용하여 분석하였다. 공간정보분석 기법을 통해 총 6개의 주행모드변경(제어권전환) 다발 지점이 도출되었고, 해당 지점의 중복된 정적인 ODD 구성요소 확인 결과 자율주행의 안전성에 영향을 미치는 요인은 횡단보도, 신호등, 교차로, 자전거 도로, 포켓차로, 주의 표지판, 중앙분리대로 나타났다. 이러한 공간정보분석을 통한 자율주행의 공간적 요인분석은 자율주행기술개발혁신사업의 리빙랩 도시뿐만 아니라 현재 확대·운영되고 있는 자율주행차 시범운행지구에서 자율주행서비스 운영지구 선정에도 기초연구로 활용될 것으로 기대한다.

• Journal of Information Processing Systems
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• 제13권2호
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• pp.285-304
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• 2017

Big data information and pattern analysis have applications in many industrial sectors. To reduce energy consumption effectively, the eco-driving method that reduces the fuel consumption of vehicles has recently come under scrutiny. Using big data on commercial vehicles obtained from digital tachographs (DTGs), it is possible not only to aid traffic safety but also improve eco-driving. In this study, we estimate fuel consumption efficiency by processing and analyzing DTG big data for commercial vehicles using parallel processing with the MapReduce mechanism. Compared to the conventional measurement of fuel consumption using the On-Board Diagnostics II (OBD-II) device, in this paper, we use actual DTG data and OBD-II fuel consumption data to identify meaningful relationships to calculate fuel efficiency rates. Based on the driving pattern extracted from DTG data, estimating fuel consumption is possible by analyzing driving patterns obtained only from DTG big data.

• 시스템엔지니어링학술지
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• 제18권2호
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• pp.40-49
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• 2022

Remote-controlled and autonomous driving based on artificial intelligence are key elements required for unmanned combat vehicles. The required capability of such an unmanned combat vehicle should be expressed in reasonable required operational capability(ROC). To this end, in this paper, the requirements of an unmanned combat vehicle operated under a manned-unmanned teaming were analyzed. The functional requirements are remote operation and control, communication, sensor-based situational awareness, field environment recognition, autonomous return, vehicle tracking, collision prevention, fault diagnosis, and simultaneous localization and mapping. Remote-controlled and autonomous driving of unmanned combat vehicles could be achieved through the combination of these functional requirements. It is expected that the requirement analysis results presented in this study will be utilized to satisfy the military operational concept and provide reasonable technical indicators in the system development stage.

• 대한기계학회논문집A
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• 제26권5호
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• pp.969-975
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• 2002

Visual effects are important cues for providing occupants with virtual reality in a vehicle simulator which imitates real driving. The viewpoint of an occupant is sensitively dependent upon the occupant's posture, therefore, the total human body motion must be considered in a graphic simulator. A real-time simulation is required for the dynamic analysis of complex human body motion. This study attempts to apply a neural network to the motion analysis in various driving situations. A full car of medium-sized vehicles was selected and modeled, and then analyzed using ADAMS in such driving conditions as bump-pass and lane-change for acquiring the accelerations of chassis of the vehicle model. A hybrid III 50%ile adult male dummy model was selected and modeled in an ellipsoid model. Multibody system analysis software, MADYMO, was used in the motion analysis of an occupant model in the seated position under the acceleration field of the vehicle model. Acceleration data of the head were collected as inputs to the viewpoint movement. Based on these data, a back-propagation neural network was composed to perform the real-time analysis of occupant motions under specified driving conditions and validated output of the composed neural network with MADYMO result in arbitrary driving scenario.

• 조명전기설비학회논문지
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• 제22권11호
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• pp.9-14
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• 2008

This paper presents the performance analysis of 10[Gb/s] optical duobinary transmitters with the non-ideal Mach-Zehnder modulator which does not have exactly 50/50 splitting/combining ratios by computer simulations. For driving voltage ratios(=driving voltage/switching voltage) with smaller than 100[%], the transmission performance has been greatly affected by extension of LPF bandwidths. Nevertheless, the performance has been degraded when the driving voltage ratio is 100[%]. The smaller driving voltage ratios has, the more sensitivity improves by extension of LPF bandwidths under the asymmetry condition. But the driving voltage ratio with 80[%] has better bit error rate(BER) than those with 50[%] and 25[%].

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.614-617
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• 1995

The unbalance heavy-load elevation driving systems are composed of rotating link-mechanism and hydraulic cylinder which actuates elevation and compensates the static unbalance moment of supporting mechanism. Control and compensation of gun driving is very difficult because these mechanism imply highly nonlinearities due to hydraulic fluid characteristics and mechanical rotation of link-mechanism. In this study, through the analysis of manufactured link-mechanism, the optimal link-mechanism design of the elevating system is suggested. Also to estimate the control performance of the unbalance heavy-load elevation servo-control driving system, modeling and simulation of the system are carried out. To prove the reliability of performance estimation program,simulation results are compared with the experimental results. Both results are similar, therefore this program will be helpful to study the control performance improvement of the system.