• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.51-56
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• 2011

The train travels on the track and, thus, the rear wheels precisely follow the paths of the front wheels. On the contrary, in the vehicles running on the road like automobiles, buses and trucks, the front wheels try to drag the rear ones toward them and across the inside of the curve. Off-tracking is defined as the radial offset between the path of the centerline of the front axle and the path of the centerline of the following axle. In the case of the bimodal tram with AWS(all wheel steering), the off-tracking decrease but the rear swing-out values increase because of the rear steering at the reverse phase angle. Thus, in order to determine the swept path width, maximum road width at the minimum turning radius, off-tracking and swing-out should be considered for the bimodal tram. In this paper, trajectory simulations were carried out for the various condition such as front steering, front and rear steering and suppression of swing-out to optimize the swept path width.

• 한국정밀공학회지
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• 제23권6호
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• pp.72-80
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• 2006

Electric Power Steering (EPS) mechanism has become widely equipped in passenger vehicle due to the increasing environmental concerns and higher fuel efficiency. This paper describes the development of concurrent simulation technique and simulation integration technique of EPS control system with a dynamic vehicle system. A full vehicle model interacting with EPS control algorithm was concurrently simulated on a single bump road condition. The dynamic responses of vehicle chassis and steering system resulting from road surface impact were evaluated and compared with proving ground experimental data. The comparisons show reasonable agreement on tie-rod load, rack displacement, steering wheel torque and tire center acceleration. This concurrent simulation capability was employed fur EPS performance evaluation and calibration as well as for vehicle handling performance integration and synthesis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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• pp.2671-2674
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• 2005

Auto Pilot 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, modem control theories are being used widely in analyzing and designing the ship system. Though P.I.D type auto pilots are widely used in ships, the stability and the adjusting meyhods are not clarified. In this paper the authors proposed auto pilot 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 investi gated 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 2003년도 춘계학술대회 논문집
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• pp.472-475
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• 2003

Electric Power Steering (EPS) mechanism has become widely equipped in passenger vehicle due to the environmental consciousness and higher fuel efficiency. This paper describes the development of co-simulation technique and simulation integration technique of EPS control system with dynamic vehicle model. A full vehicle model interacted with EPS control algorithm is concurrently simulated on a single bump road condition. Dynamic responses of vehicle chassis and steering system resulting from road surface impact are evaluated and compared with proving ground experimental data. The comparisons will show reasonable agreement on tie-rod load. rack displacement, handle-wheel torque and tire center acceleration. This developed simulation capability can be used for EPS performance evaluation and calibration as well as for vehicle handling performance integration and synthesis.

• 한국멀티미디어학회논문지
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• 제19권3호
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• pp.539-547
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• 2016

Automated guided vehicles (AGVs) are widely used in industry. Several types of vision-based AGVs have been studied in order to reduce cost of infrastructure building at floor of workspace and to increase flexibility of changing the navigation path layout. A practical vision-based guideline tracing method is proposed in this paper. A virtual tracing wheel is introduced and adopted in this method, which enables a vision-based AGV to trace a guideline in diverse ways. This method is also useful for preventing damage of the guideline by enforcing the real steering wheel of the AGV not to move on the guideline. Usefulness of the virtual tracing wheel is analyzed through computer simulations. Several navigation tests with a commercial AGV were also performed on a usual guideline layout and we confirmed that the virtual tracing wheel based tracing method could work practically well.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.825-827
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• 1997

This paper presents a robot which is steered by vision system. The proposed robot system has an AM188ES CPU(5.3 MIPS) and 2DC motors with encoder and turns accurately at any speed and shows a movement like a human controlled car using a steering wheel. To the robot only steering angle value is sent without considering the speed. We present how to control this robot using our real time vision system.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.37.6-37
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• 2002

Omnidirectional mobile robots are capable of arbitrary motion in an arbitrary direction without changing the direction of wheels, because they can perform 3 degree-of-freedom (DOF) motion on a 2-dimensional plane. In this research, a new class of an omnidirectional mobile robot is proposed. Since it has synchronously steerable omnidirectional wheels, it is called an omnidirectional mobile robot with steerable omnidirectional wheels (OMR-SOW). It has 3 DOFs in motion and one DOF in steering. One steering DOF can function as a continuously variable transmission (CVT). CVT of the OMR-SOW increases the range of velocity ratio from the wheel velocities to robot velocity, which may improve...

• 로봇학회논문지
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• 제18권3호
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• pp.299-307
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• 2023

In the midst of accelerating wars around the world, unmanned robot technology that can guarantee the safety of human life is emerging. ERP-42 is a modular platform that can be used according to the application. In the field of defense, it can be used for transporting supplies, reconnaissance and surveillance, and medical evacuation in conflict areas. Due to the nature of the military environment, atypical environments are predominant, and in such environments, the platform's path followability is an important part of mission performance. This paper focuses on reducing the minimum turning radius in terms of improving path followability. The minimum turning radius of the existing 2WS/2WD in-wheel platform was reduced by increasing the torque of the independent driving in-wheel motor on the rear wheel to generate oversteer. To determine the degree of oversteer, two GPS were attached to the center of the front and rear wheelbases and measured. A closed-loop speed control method was used to maintain a constant rotational speed of each wheel despite changes in load or torque.

• 해양환경안전학회지
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• 제22권6호
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• pp.625-630
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• 2016

본 논문에서는 조타기 작동 신호에 대하여 AIS 통신을 이용하여 상호 교환함으로써 상대선의 선회정보를 보다 신속히 파악할 수 있는 선회조기감지시스템을 구축하였으며, 이를 실선에 적용하여 해당 시스템의 실효성을 검증하였다. 조타 신호가 조타기를 작동함과 동시에 AIS를 통하여 송신되어 상대선의 ECDIS에 사용된 타각만큼 유색으로 표시되는 것을 확인하였다. 선회조기감지시스템을 통하여 상대선의 변침 상황을 조기에 감지할 수 있었으며, 이를 통한 선박 상호간 충돌회피가 조기에 가능할 것으로 판단된다. 또한, 의심 선박에 대한 VTS의 적극적 관제가 가능하고, 해양안전종합정보시스템을 통한 해양사고 분석에도 활용 가능할 것이다.

• 해양환경안전학회지
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• 제19권1호
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• pp.17-22
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• 2013

가까운 거리에서 상대선과의 마주치는 상황 또는 교차된 상황에서 상호 피항동작을 취하게 되는데, 상대선박의 변침의도를 정확히 파악하지 못해 서로 같은 방향으로 피항동작을 취함으로써 충돌위험에 처하게 되기도 한다. 항해사는 피항동작을 취함에 있어 시각에 의한 판단, 레이더 또는 AIS 벡터를 이용한 판단, 또는 VHF 통신을 활용하여 피항동작을 취하고 있으나, 레이더 및 AIS를 이용한 기존의 방식은 선박이 선회 후 선수방위가 표시되기 때문에 선회를 탐지하기까지는 상당한 시간이 요구된다. 따라서 조타기 작동 신호를 상대선박에 신속하게 전달하여 상대선의 선회의도를 보다 신속히 판단할 수 있는 선회조기감지 방안을 제안하였다. 이러한 방법은 상대선의 변침의도를 보다 신속하게 파악함으로써 선박 상호간 충돌예방에 효과적이며, VTS 시스템 및 해양사고 분석에서 활용이 가능하다.