• 한국자동차공학회논문집
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• 제10권6호
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• pp.202-208
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• 2002

Ball k nut type steering gear box has disadvantages on on-center range as compared with rack & pinion type because of many linkages. In this study, a technique which can improve the on-center loose feel is introduced. The improvement can be obtained by putting simple devices on steering gear box valve body which can change the stiffness of steering gear on on-center handling range. Analysis and test of the vehicle with improved steering system are performed.

• 한국자동차공학회논문집
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• 제17권1호
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• pp.58-63
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• 2009

Flow rate of the power steering oil pump is affected by oil temperature, engine rpm and pressure of pump. In this paper, considering those conditions, approximate model expressed by flow rate characteristics between hydraulic power steering oil pump and steering gear is proposed. Oil pump displacement is considered to be 9.6cc/rev. which is adapted to mid size car. Flow rate of the oil pump is predicted from the proposed model and compared with experimental data. And catch-up is also predicted in each steering wheel speed and is compared with experimental results.

• 한국항만학회지
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• 제13권2호
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• pp.381-388
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• 1999

To improve the productivity in the harbor, successful development of an UCT(Unmanned Container Transporter) is needed. Well-designed steering and velocity control systems are the key factor for the development of the UCT. In this paper, a research concerning the achievement of the steering control is introduced. To get an information on the guide line that the UCT should track, the vision system is applied. By using neural network, proper steering angle is gotten fast with less influence of the image disturbance. A simulation based on the UCT kinematics is performed with the measured steering angle, and it shows satisfactory results.

• 전기학회논문지
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• 제61권5호
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• pp.735-743
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• 2012

In this paper, we present model predictive control (MPC) applied to lane keeping system (LKS) based on a vision module. Due to a slow sampling rate of the vision system, the conventional LKS using single rate control may result in uncomfortable steering control rate in a high vehicle speed. By applying MPC using multi-rate Kalman filter to active steering control, the proposed MPC-based active steering control system prevents undesirable saturated steering control command. The effectiveness of the MPC is validated by simulations for the LKS equipped with a camera module having a slow sampling rate on the curved lane with the minimum radius of 250[m] at a vehicle speed of 30[m/s].

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.114-117
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• 2005

Auto Steering System is the device for course keeping or course altering to ship's steering system. The Purpose of automatic steering system is to keep the ship's course stable with the minimum course and rudder angle. Recently, modern control theories are being used widely in analyzing and designing the ship system. Though P.D type auto pilots are widely used in ships, the stability and the adjusting methods are not clarified. In this paper the authors proposed auto steering system with Fuzzy Logic Controller. In the fuzzy control the things that the actual operators of a steering wheel has acquired through their experience can be logically described by the Lingustic Control Rule. The characteristic of the control system were investigated through the computer simulation results. it was found that the fuzzy logic control was more efficient than the conventional system.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.281-282
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• 2012

• 한국진공학회지
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• 제15권4호
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• pp.410-420
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• 2006

Epitaxial 성장에서 screening 및 steering 효과 등과 같은 증착과정 중 나타나는 dynamic effects를 kinetic Monte Carlo 시뮬레이션으로 고찰하였다. 증착원자와 토대 원자와의 상호 작용을 엄밀하게 고려하기 위해 이 시뮬레이션 프로그램에 molecular dynamics 시뮬레이션을 결합시켰다. 기울어진 각도로 증착 시킬 경우 표면의 형상은 1) 증착 각도가 기울어짐에 따라 거칠기가 증가한다는 것, 2) 비대칭적인 언덕의 형성된다는 것, 그리고 3) 언덕의 면방향에 따라 비대칭적인 기울기를 갖는다는 세가지 특징을 보았다. 증착 각도나 온도 의존성에 대한 시뮬레이션 결과는 기존의 실험 결과와 잘 일치하는 것을 확인하였다. 기울어진 각도로 증착했을 때 나타나는 이러한 결과는 steering과 screening 효과에 따른 초기 증착 밀도의 불균일에 기인함을 알 수 있었고, 여기서 steering 효과가 screening 효과 보다 주요한 역할을 하는 것을 보았다. 시뮬레이션 계산에서 확인된 새로운 결과는 기울기 선택 (slope selection)이 이루어졌어도 언덕의 각 면이 단일한 기울기로 형성되어 있지 않고 여러 종류의 facet가 섞인 형태이며, 따라서 기울기 선택이 바로 facet 선택을 의미하지는 않는다는 것이다.

• 센서학회지
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• 제10권5호
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• pp.329-336
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• 2001

This paper describes the steering control and geomagnetism cancellation for an autonomous vehicle using an MR sensor. The magneto-resistive (MR) sensor obtains the vector summation of the magnetic fields from embedded magnets and the Earth. The vehicle is controlled by the magnetic fields from embedded magnets. So, geomagnetism is the disturbance in the steering control system. In this paper, we propose a new method of the sensor arrangement in order to remove the geomagnetism and vehicle body interference. The proposed method uses two MR sensors located in a level plane and the steering controller has been developed. The controller has three input variables ($dB_x$, $dB_y$, $dB_z$) using the measured magnetic field difference, and an output variable (the steering angle). A simulation program was developed to acquire the data to teach the neural network, in order to test the ability of a neural network to learn the steering control process. Also, the computer simulation of the vehicle (including vehicle dynamics and steering) was used to verify the steering performance of the vehicle controller using the neural network. From the simulation and field test, good result was obtained and we confirmed the robustness of the neural network controller in a real autonomous vehicle.

• 드라이브 ㆍ 컨트롤
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• 제12권3호
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• pp.36-43
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• 2015

An autonomous vehicle control algorithm based on Ackerman Geometry is known to be reliable in low tire slip situation. However, vehicles at high speed make lateral errors due to high tire slip. In this paper, considering the tire slip of vehicles, the steering angle is determined based on the Ackerman Geometry and is supplemented tire slip angle by the Stanley steering algorithm. In addition, to prevent the tire slip, the algorithm, which restricts steering if a certain level of slip occurs, is used to reduce the lateral error. While many studies have been extended to include vehicle slip, studies also need to be carried out on the tire slip depending on hardware performance. The control algorithm of autonomous vehicles is compensated considering the sensor noise and the performance of steering actuator. Through the various simulations, it was found that the performance of steering actuator was the key factor affecting the performance of autonomous driving. Also, it was verified that the usefulness of steering algorithm considering the tire slip and performance of steering actuator.

• 한국문헌정보학회지
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• 제56권3호
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• pp.93-117
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• 2022

본 연구는 충청지역을 중심으로 공공도서관 운영위원회 관련 조례 내용 중 도서관 운영위원회 관련 내용을 분석하여 문제점과 시사점을 도출하고 이를 기반으로 도서관 운영에 도움이 될 수 있는 운영위원회 조례 구성에 필요한 내용 및 보완 사항 등을 제안하고자 하였다. 이를 위해 첫째, 공공도서관 운영위원회의 의의와 역할, 조례의 성격에 관한 이론적 배경에 대해 살펴보았다. 둘째, 운영위원회 관련 조례제정 현황, 운영위원회 관련 조항 포함 여부, 구성 내용, 구성방식, 기능, 회의와 규정제정 및 수당지급 등 5개 영역으로 구분하여 분석하였다. 이 분석을 토대로 조례 담당 부서, 도서관운영위원회 의무 설치, 위원 구성에 있어 도서관장, 도서관 전문가의 참여 보장, 정기회의 개최, 회의록 공개, 위원회 심의 결과 반영 등이 필요함을 언급하였다. 또한 향후 도서관운영원회 관련 표준조례안 제정 시 운영위원회의 명칭, 성격과 역할, 구성, 회의, 하위 조직이나 규칙 제정 등에 관한 사항을 포함해야함을 제안하였다.