• 대한교통학회지
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• 제35권4호
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• pp.332-347
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• 2017

자율주행기술이 교통류에 미치는 영향을 분석하기 위해서는 자율차와 비자율차 간의 상호작용을 분석하는 것이 중요한 이슈이다. 특히 자율주행기술을 활용한 유용한 서비스 중의 하나인 군집주행은 주변의 비자율 차량의 주행행태에 영향을 미칠 수 있다. 본 연구의 목적은 군집주행 환경에서 비자율차의 차로변경행태 분석하는 것이며, 3단계의 실험 및 조사를 수행하였다. 1단계 영상기반 인지특성 분석을 통해 군집주행 환경에서 어떠한 반응행태를 보일 것인지를 조사하였으며, 2단계 주행시뮬레이션 실험을 통해 비자율차의 차로변경행태를 분석하였다. 차로변경행태를 분석하기 위해 차로변경시간과 교통류의 안전성을 나타낼 수 있는 지표인 가속소음을 이용하였으며, 자율차의 시스템 보급률(Market Penetration Rate, MPR)과 피실험자 인적요소에 따른 비자율차의 주행행태 차이를 비교 분석하였다. 마지막 단계인 NASA-TLX(NASA Task Load Index)를 통해 비자율차 운전자의 작업부하를 평가하였다. 분석결과 군집차량군 주변의 비자율차 운전자는 심리적인 부담감을 느끼며, MPR이 증가할수록 차로변경시간이 길어지고 30-40대 운전자 또는 여성 운전자의 경우 안전성이 낮아지는 것으로 나타났다. 본 연구에서 도출된 결과는 자율차와 비자율차의 상호작용을 반영한 보다 현실성 높은 교통시뮬레이션 실험 시 기초자료로 활용될 수 있고, 이를 기반으로 자율협력주행 환경에서 적용 가능한 교통운영관리전략 수립을 효과적으로 지원할 것으로 기대된다.

• 한국자동차공학회논문집
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• 제19권3호
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• pp.16-22
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• 2011

This paper presents the potential of in-vehicle data recorder system for monitoring aggressive driving patterns and providing feedback to drivers on their on road behaviour. This system can detect 10 risky types of drivers' driving patterns such as aggressive lane change, sudden brakes and turns with acceleration etc. Vehicle dynamics simulation and vehicle road test have been performed in order to develop driving pattern recognition algorithms. Recorder systems are installed to 50 buses in a single company. Drivers' driving behaviour are monitored for 1 month. The drivers' risky driving data collected by the system are analyzed. Aggressive lane change in 50km/h below is a cause in overwhelming majority of risky driving pattern.

• 한국항행학회논문지
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• 제11권4호
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• pp.359-370
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• 2007

무인 자동차 시스템에 있어 차선추적과 물체회피 기술은 중요한 핵심기술 이다. 본 논문에서는 차량제어와 모델링, 센서 실험을 통하여 차선추적 및 물체회피 방법을 제안하고자 한다. 첫 번째 물체회피는 가/감속을 위한 종 방향 제어와 조향제어에 의한 횡 방향 제어 두 개의 부분으로 구성되어 진다. 각각의 시스템은 무인자동차의 제어를 위하여 차량의 위치, 주변환경 인식, 상황에 따른 빠른 처리를 요구한다. 차량의 제어 전략이 작동되는 동안 도로에서의 물체인식과 회피는 차량의 속도에 달려 있다. 두 번째 영상시스템을 통한 차선추석방법을 설명한다. 이 또한 두 부분으로 구성된다. 첫 번째 횡/종 제어를 위한 로도 모델이 포함된다. 두 번째 차선추적방법, 영상처리 알고리즘, 필터링 방법 및 영상처리 방법을 다룰 것이다. 마지막으로 본 논문에서는 실차실험을 통한 차선추적 및 물체회피 차량제어 및 모델링 방법을 제안한다.

• 한국자동차공학회논문집
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• 제8권6호
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• pp.194-207
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• 2000

In this paper, we suggest a vision-based lane change control system, which can be applied on the straight road, without additional sensors such as a yaw rate sensor and a lateral accelerometer. In order to reduce the image processing time, we predict a reference line position during lane change using the lateral dynamics and the inverse perspective mapping. The sliding mode control algorithm with a boundary layer is adopted to overcome variations of parameters that significantly affects a vehicle`s lateral dynamics and to reduce chattering phenomenon. However, applying the sliding mode control to the system with a long sampling interval, the stability of a control system may seriously be affected by the sampling interval. Therefore, in this paper, a look ahead offset has been used instead of a lateral offset to reduce the effect of the long sampling interval due to the image processing time. The control algorithm is developed to follow the desired trajectory designed in advance. In the design of the desired trajectory, we take account of the constraints of lateral acceleration and lateral jerk for ride comfort. The performance of the suggested control system is evaluated in simulations as well as field tests.

• 한국자동차공학회논문집
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• 제8권4호
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• pp.121-129
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• 2000

this paper develops a computational model for the turning maneuver analysis of a cabover type heavy truck. The model having 42 degree-of-freedom is developed using ADAMS. Leaf springs used in the front and rear suspension systems are modeled by dividing it three links and joining them with joints. Force and displacement relationship showing nonlinear hysteric characteristics of the leaf spring is measured and modeled with an exponential function. A velocity and force relationship of a shock absorber is measured and modeled with a spline function. And a stabilizer bar is modeled using ADAMS beam element to consider a twisting and bending effect. To verify the developed model an actual vehicle test is performed in the double lane change course with 50kph and 60kph vehicle velocity. In the actual vehicle test lateral acceleration roll angle and yaw rate are measured, The tendency and peak-to-peak values of the actual vehicle test and simultion results are compared each other.

• 한국자동차공학회논문집
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• 제9권5호
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• pp.157-164
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• 2001

This paper performs static and dynamic tests of a multi-leaf spring and a tapered leaf spring to investigate their hysteretic characteristics. In the static test, trapezoidal input load is applied with 0.1Hz excitation frequency and with zero initial loading conditions. In the dynamic test, sinusoidal input load is applied with five excitation amplitudes and three excitation frequencies. In these tests, static and dynamic hysteretic characteristics of the multi-leaf spring and the tapered leaf spring are compared, and, the effects of excitation amplitudes and frequencies on dynamic spring rate are also shown. In this paper, actual vehicle tests are performed to study the effects of hysteretic characteristics of the large-sized truck's handling performance. The multi-leaf spring or the tapered leaf spring is used in the front suspension. The actual vehicle test is performed in a double lane change track with three velocities. Lateral acceleration, yaw rate and roll angle are measured using a gyro-meter located at the mass center of the cab. The test results showed that a large-sized truck with a tapered leaf spring needs to have an additional apparatus such as roll stabilizer bar to increase the roll stabilizer due to hysteretic characteristics.

• 대한토목학회논문집
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• 제43권2호
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• pp.219-230
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• 2023

도시의 토지이용은 지속적으로 고도화, 광역화 추세로 도로와 접한 주변 토지들은 다양한 용도의 시설물 건설과 함께 진출입부 접속도 증가하고 있다. 그러나 구체적인 진출입부 설치 기준이 없는 상황에서 부적절한 접속위치와 접속형태, 그리고 운영방식은 기존 가로 및 교차로의 교통 서비스수준을 악화시키고 있다. 이에 본 연구는 도시부 보조간선도로와 집산도로에 접속되는 진출입부의 교통상의 영향 최소화를 위해 첫째, 진출입부와 접한 도로·교통 환경을 고려하여 상·하류부 교차로의 대기행렬 길이와 진출입부에서 교차로간 차로변경에 필요한 소요길이를 재정립하여 기존 상·하류 교차로 사이에서 물리적으로 접속 가능한 진출입부 접속위치 및 접속형태 결정 기준을 제시하였다. 둘째, 진출입부 접속형태(신호교차로, 단순접속교차로)에 따른 좌회전차로와 가·감속차로의 교통시설 설치 비용과 진출입부 설치 전·후의 교통 비용의 차이인 부(-)의 사회적 비용을 통해 사업지 임계유발량을 산정한 후 주변 교차로 서비스수준과의 관계로부터 진출입부 운영방식을 정량적으로 결정할 수 있음을 제시하였다.

• 한국생산제조학회지
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• 제21권4호
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• pp.683-690
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• 2012

In this work, the semi-active control of a large-sized bus suspension system with an MR damper was studied. An MR damper model that can aptly describe the hysteretic characteristics of an MR damper was adopted. Parameter values of the MR damper model were suitably modified by considering the maximum damping force of a passive damper used in the suspension system of a real large-sized bus. In addition, a fuzzy logic controller was developed for semi-active control of a suspension system with an MR damper. The vertical acceleration at the attachment point of the MR damper and the relative velocity between sprung and unsprung masses were used as input variables, while voltage was used as the output variable. Straight-ahead driving simulations were performed on a road with a random road profile and on a flat road with a bump. In straight-ahead driving simulations, the vertical acceleration and pitch angle were measured to compare the riding performance of a suspension system with a passive damper with that of a suspension with an MR damper. In addition, a single lane change simulation was performed. In the simulation, the lateral acceleration and roll angle were measured in order to compare the handling performance of a suspension system using a passive damper with that of a suspension system using an MR damper.

• 대한안전경영과학회지
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• 제20권2호
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• pp.1-8
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• 2018

This study aims to provide a real-time information to the driver by effectively operating the advanced safety device attached to the freight vehicle, thereby minimizing insecure behavior of the driver such as speeding, rapid acceleration, sudden braking, And improve driving habits to prevent accidents and save energy. Advanced safety equipment is a device that warns the driver that the vehicle leaves the driving lane regardless of the intention of the driver and reduces the risk of traffic accidents by mitigating or avoiding collision by detecting a frontal collision during driving.The main contents of this report are as follows: In case of installing a warning device on a lane departing vehicle (excluding a light vehicle) and a lorry or special vehicle with a total weight exceeding 3.5 tonnes, the driver must continue to operate unless the driver releases the function.In addition, when the automatic emergency braking system is installed, the structure should be such that the braking device is operated automatically after warning the driver when the risk of collision with the running or stopped vehicle in the same direction is detected in front of the driving lane.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.91.1-91
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• 2001

The subject of this paper is vision system analysis of the autonomous vehicle. But, autonomous vehicle is one of the difficult topics from the point of view of several constrains on mobility, speed of vehicle and lack of environment information. Therefore, we are application of the vision system so that autonomous vehicle. Vision system of autonomous vehicle is likely to eyes of human. This paper can be divided into 2 parts. First, acceleration system and brake control system for longitudinal motion control. Second vision system of real time lane detection is for lateral motion control. This part deals lane detection method and image processing method. Finally, this paper focus on the integration of tole-operating vehicle and autonomous ...