• 한국항만학회지
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• 제14권3호
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• pp.291-301
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• 2000

T his paper presents the lateral and longitudinal control algorithm for the driving of a 4WS AGV(Automated Guided Vehicle). The control law to the lateral and longitudinal control of the AGV includes adaptive agin tuning ability, that is the controller gain of the gravity compensated PD controller can be changed on a real-time. The gain tuning law is derived from the Lyapunov direct method using the output error of the reference model and the actual model, And to show the performance of the presented lateral and longitudinal control algorithm, we simulate toe nonlinear AGV equations of the motion by deriving the Newton-Euler Method, The read path is from quay yard area to docking position in loading yard area. The quay yard area is where the quay crane loads the container to the AGV and the docking position is where the container is transferred to the gantry crane. The road types are constructed in a straight line and J-turn. When driving the straight line, the driving velocity is 6㎧ and the J-turn is 3㎧.

• 자동차안전학회지
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• 제9권3호
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• pp.24-30
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• 2017

This paper presents the development of laser scanner based static obstacle detection algorithm for vehicle localization on lane lost section. On urban autonomous driving, vehicle localization is based on lane information, GPS and digital map is required to ensure. However, in actual urban roads, the lane data may not come in due to traffic jams, intersections, weather conditions, faint lanes and so on. For lane lost section, lane based localization is limited or impossible. The proposed algorithm is designed to determine the lane existence by using reliability of front vision data and can be utilized on lane lost section. For the localization, the laser scanner is used to distinguish the static object through estimation and fusion process based on the speed information on radar data. Then, the laser scanner data are clustered to determine if the object is a static obstacle such as a fence, pole, curb and traffic light. The road boundary is extracted and localization is performed to determine the location of the ego vehicle by comparing with digital map by detection algorithm. It is shown that the localization using the proposed algorithm can contribute effectively to safe autonomous driving.

• Advances in Automotive Engineering
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• 제1권1호
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• pp.123-141
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• 2018

Hardware-in-the-loop (HiL) simulation is a very powerful tool to design, test and verify automotive control systems. However, well-validated and high degree of freedom vehicle models have to be utilized in these simulations in order to obtain realistic results. In this paper, a vehicle dynamics model developed in the Carsim Real Time program environment and its validation has been performed using experimental results. The developed Carsim real time model has been employed in the Tofas R&D hardware-in-the-loop simulator. Experimental and hardware-in-the-loop simulation results have been compared for the standard FMVSS No. 126 test and the results have been found to be in good agreement with each other. Two electronic stability control (ESC) algorithms, named the Basic ESC and the Integrated ESC, taken from the earlier work of the authors have been tested and evaluated in the hardware-in-the-loop simulator. Different evaluation methods have been formulated and used to compare these ESC algorithms. As a result, the Integrated ESC system has been shown superior performance as compared to the Basic ESC algorithm.

• 자동차안전학회지
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• 제14권2호
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• pp.20-25
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• 2022

This paper represents an adaptive Region of Interest (ROI) decision for real-time performance in an autonomous driving perception module. Since the whole automated driving system consists of numerous modules and subdivisions of module occur, it is necessary to consider the characteristics, complexity, and limitations of each module. Furthermore, Light Detection And Ranging (Lidar) sensors require a considerable amount of time. In view of these limitations, division of submodule is inevitable to represent high real-time performance for stable system. This paper proposes ROI to reduce the number of data respect to computation time. ROI is set by a road's design speed and the corresponding ROI is applied differently to each vehicle considering its speed. The simulation model is constructed by ROS, and overall data analysis is conducted by Matlab. The algorithm is validated using real-time driving data in urban environment, and the result shows that ROI provides low computational costs.

• 대한교통학회지
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• 제36권2호
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• pp.67-85
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• 2018

차량의 자율주행기술과 차량간 무선통신을 통한 정보공유 군집주행 서비스가 실현되고 있다. 군집주행이란 여러대의 차량이 최소한의 안전거리만 유지한 채 일정한 간격을 두고 주행하는 기술이다. 이러한 군집주행은 도로의 용량을 증대시키고, 안전성을 향상시키며, 연료소비를 줄일 수 있는 잠재력을 가지고 있어 교통류 운영효율성, 안전성, 환경성 문제를 해결할 수 대안으로 주목받고 있다. 그러나 군집주행차량과 주변의 일반차량간의 적절한 상호작용이 가능할 때 교통류의 성능은 최적화 될 수 있다. 특히 교통운영 관리자는 화물차가 군집주행을 할 경우 유입연결로에서 비자율차가 안전하게 진입할 수 있도록 군집간간격과 군집크기와 같은 군집주행 파라미터를 조정하여 안전성과 운영효율성을 극대화시킬 수 있어야 한다. 본 연구에서는 고속도로 유입연결로 구간에서 교통류 퍼포먼스를 극대화 시킬 수 있는 화물차 군집 운영전략을 수립할 수 있는 방안을 제시하였다. 운영효율성을 평가하기 위한 지표는 주행속도로 설정하였으며, 안전성 평가를 위해서 비자율차의 차량추종 관계 대비 상충상황에 노출되는 빈도를 나타내는 비자율차 상충률의 개념을 정의하여 적용하였다. 또한 분석결과를 이용하여 최적 군집운영 조건을 판단하는 방법론을 제시하였으며, 군집간간격이 50m이고 군집크기가 6대인 운영시나리오가 최적의 성능을 유도할 수 있음을 확인하였다. 본 연구에서 제시한 운영전략 수립 방안에 따라 운영효율성과 안전성을 고려한 교통상황별 적정 군집주행 파라미터를 도출할 수 있으며, 이는 군집운영 전략을 지원할 수 있는 자료로 활용할 수 있을 것으로 기대된다.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2002년도 춘계학술대회 논문집
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• pp.57-62
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• 2002

This study described the specification and configuration of developed fixed-base AHS (Automated Highway System) simulator fur the human factors researches, and its usability evaluation results after riding 120, 140, and 160kph automated driving speed. As the results, this study suggested the subjects' preferences and opinions about simulator and AHS configurations that would help to establish the AHS R&D plan and driver-vehicle/road interface design guidelines as the basic researches of the AHS human factors.

• 한국ITS학회 논문지
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• 제21권5호
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• pp.197-217
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• 2022

자율주행자동차(Automated vehicle, AV) 교통사고가 지속적으로 발생하면서 자율주행시스템(automated driving system, ADS)의 안전성 및 신뢰성을 확보하기 위한 안전성 검증의 중요성이 강조되고 있다. 안전성 및 신뢰성을 확보하기 위해서는 ADS의 운행가능영역(operational design domain, ODD)을 정의하고 ODD를 벗어나는 상황에서의 대응 능력을 평가하면서 ADS의 안전성을 검증해야 할 필요가 있다. 이를 위해 SAE, BSI, NHTSA, ISO 등의 국제 기구에서는 ODD 분류 기준 및 표준을 규정하고 있으나 국내의 경우 ODD 기준이 부재하여 AV의 ODD 표현 방법 및 안전성 검증 및 평가가 적절히 이루어지지 않고 있다. 이에 본 연구에서는 해외 ODD 분류 기준을 분석하고 안전성 검증 및 평가에 적합한 분류 기준을 선정하였다. 선정된 ODD를 기반으로 ADS 안전성 검증 및 평가에 필요한 평가요소를 제시하였다. 특히, ADS 기술 개발을 지원하는 자율주행 실험도시(K-City)의 평가환경을 분석하여 평가요소를 제시하였다.

• 자동차안전학회지
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• 제14권3호
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• pp.65-70
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• 2022

Lane change in urban environments is a challenge for both human-driving and automated driving due to their complexity and non-linearity. With the recent development of deep-learning, the use of the RNN network, which uses time series data, has become the mainstream in this field. Many researches using RNN show high accuracy in highway environments, but still do not for urban environments where the surrounding situation is complex and rapidly changing. Therefore, this paper proposes a lane change possibility decision network by adopting Attention layer, which is an SOTA in the field of seq2seq. By weighting each time step within a given time horizon, the context of the road situation is more human-like. A total 7D vectors of x, y distances and longitudinal relative speed of side front and rear vehicles, and longitudinal speed of ego vehicle were used as input. A total 5,614 expert data of 4,098 yield cases and 1,516 non-yield cases were used for training, and the performance of this network was tested through 1,817 data. Our network achieves 99.641% of test accuracy, which is about 4% higher than a network using only LSTM in an urban environment. Furthermore, it shows robust behavior to false-positive or true-negative objects.

• 자동차안전학회지
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• 제11권3호
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• pp.13-18
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• 2019

According to the development of autonomous vehicles worldwide, the driver's posture may not be a normal posture but the various seating positions. Recently, a numbers of research activities has been focused to protect of driver and passengers in various seating positions as well as seating postures. In this paper, the occupant injury severity was evaluated with different seat positions, seatback angles and TTF times.

• 한국자동차공학회논문집
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• 제7권5호
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• pp.96-106
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• 1999

In this study, the advanced shift control algorithm for parallel type hybrid drivetrain system with automated manual transmission(AMT) is proposed. The AMT can be easily realized by mounting the pneumatic actuators and sensors on the clutch and shift levers of the conventional manual transmission. By using the electronic-controlled AMT, engine and induction machine, it is possible to achieve the integrated control of overall system for the efficiency and the performance of the vehicle. Performing the speed control of the induction machine and the engine, the synchronization at gear shifting and the smooth engagement of clutch can be guaranteed. And it enables to reduce the shift shock and shorten the shift time. Hence, it results in the improvement of shift quality and the driving comfort of the vehicle. Dynamometer-based experiments are carried out to prove the validity of the proposed shift control algorithm.