• 제어로봇시스템학회논문지
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• 제20권7호
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• pp.701-705
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• 2014

This article presents a comparison among several yaw and roll motion controllers for vehicle rollover prevention. In the previous research, yaw and roll motion controllers can be independently designed for rollover prevention. Following this idea, several yaw and roll motion controllers are designed and compared in terms of rollover prevention. For the yaw motion control, PID, LQR, SMC (Sliding Mode Control) and TDC (Time-Delay Control) are adopted. For the roll motion control, LQR, LQ SOF (Static Output Feedback) control, PID, and SMC are adopted. To compare the performance of each controller, simulation is performed on a vehicle simulation package, CarSim$^{(R)}$. From simulation, TDC and LQ SOF are the best for yaw and roll motion control, respectively.

• 한국항공우주학회지
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• 제37권7호
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• pp.709-716
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• 2009

위성 궤도 자세는 위성 열설계에 영향을 주는 중요한 요소로서, 궤도 운용 자세에 대한 열적 조건을 정확히 파악하는 것을 필요로 한다. 본 연구에서는 저궤도 위성의 yaw motion의 운영 자세에 따른 우주 열환경의 변화와 열설계의 열적 영향을 검토하였다. 본 위성은 고정형의 태양 전지판을 가지고 있기 때문에 태양광 구간 동안에 태양지향(sun-pointing)자세를 유지하고, 위성에 장착되는 별센서인 별추적기의 가시 방향이 심층 우주방향을 향하도록 하기 위하여 위성의 길이 방향을 축으로 일정한 각속도로 회전을 하는 yaw motion을 하도록 운용된다. 이것은 위성이 정밀한 자세 제어의 성능을 발휘할 수 있도록 별추적기가 별의 시야각을 확보하기 위한 것이다. 또한 위성 열설계 측면에서는 이러한 운용을 위한 자세 변화에 따른 열적 영향을 파악하는 것을 필요로 한다. 연구에서는 위성의 열모델에 이러한 궤도 운용 자세를 반영한 후의 궤도 열해석을 통하여 이를 알아보고자 한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.212-217
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• 2011

A scheduling technique for the improvement of yaw motion stability in in-wheel motor vehicle is proposed. Normally vehicle velocity is controlled via conventional PID method. When vehicle is encountered with different road conditions on left and right hand sides, unstable yaw motion is induced due to the driving force difference in both wheels. In this paper a scheduling formular for control gain is derived in terms of experimental results to generate proper counter control action. Simulation result reveals its effective performance in yaw control of in-wheel vehicle.

• 한국기계연구소 소보
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• 통권15호
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• pp.5-17
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• 1985

Dynamics of railway vehicles are strongly influenced by the wheel/rail contact forces. Wheel/rail contact geometric characteristics are important parameters to determining wheel/rail contact forces. In general, geometric relations between wheel and rail are represented by nonlinear functions of the wheelset lateral excursion and the relative yaw angle. There are some analytical and experimental studies to show the influences of the wheelset lateral displacement on wheel/rail geometric relations. Recently radial steering bogie which is designed to have flexible yaw motions of wheelsets was developed to improve curve negotiation performance. The radial steering bogie makes it important problem to study the effects of wheelset yaw motion on wheel/rail geometric relations. This paper describes the method to analyze 3-dimensional wheel/rail contact geometry considering wheelset yaw motion and describes also some computer simulation results.

• 대한기계학회논문집A
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• 제30권12호
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• pp.1551-1556
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• 2006

Two yaw motion control systems that improve a vehicle lateral stability are proposed in this study: a rear wheel steering yaw motion controller (SESP) and an enhanced rear wheel steering yaw motion controller (ESESP). A SESP controls the rear wheels, while an ESESP steers the rear wheels and front outer wheel to allow the yaw rate to track the reference yaw rate. A 15 degree-of-freedom vehicle model, simplified steering system model, and driver model are used to evaluate the proposed SESP and ESESP. A robust anti-lock braking system (ABS) controller is also designed and developed. The performance of the SESP and ESESP are evaluated under various road conditions and driving inputs. They reduce the slip angle when braking and steering inputs are applied simultaneously, thereby increasing the controllability and stability of the vehicle on slippery roads.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.336-336
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• 2000

This paper studied on the yaw motion of the gantry crane which is used for the automated container terminal. Though several problems are occurred in driving of gantry crane, they are solved by the motion by the operator. But if the gantry crane is unmanned, it is automatically controlled without any human operation. There are two types, cone and flat typo in driving wheel shape. In cone type, lateral vibration and yaw motion of crane are issued. To bring a solution to these problems, the dynamic equation of the gantry crane driving mechanism is derived and it used PD(Proportional-Derivative) controller to control the lateral vibration. The simulation result of the driving mechanism using the Runge-Kutta method is presented in this paper.

• 제어로봇시스템학회논문지
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• 제15권11호
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• pp.1130-1136
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• 2009

A new control algorithm for the yaw motion control of a unicycle robot has been proposed in this paper. With the increase of life quality, there are various transportation systems such as segway and unicycle robot which provide not only transportation but also amusement. In most of the unicycle robots share the same technology in that the directions of roll and pitch are controlled by the balance controllers, allowing the robots to maintain balance for a long period by continuously moving forward and backward. However, one disadvantage of this technology is that it cannot provide the capability to the robots to avoid obstacles in their path way. This research focuses to provide the yawing function to the unicycle robot and to control the yaw motion to avoid the obstacles as desired. For the control of yawing motion, the yaw angle is adjusted to the inertia generated by the velocity and torque of a yawing motor which is installed in the center axes of the unicycle robot to keep the lateral control simple. Through the real experiments, the effective and robustness of the yawing control algorithm has been demonstrated.

• Wind and Structures
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• 제7권1호
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• pp.41-54
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• 2004

An analysis refinement of the Messina Strait suspension bridge project has been recently required, concerning mainly the yaw angle effects on the multi-box deck section aerodynamics and the vortex shedding at low reduced velocities $V^*$. In particular the possible interaction of the axial flow with the large cross beams has been investigated. An original test rig has been designed at this purpose allowing for both forced motion and free motion aero elastic tests, varying the average angle of attack ${\alpha}$ and the deck yaw angle ${\beta}$. The hydraulic driven test rig allowed for both dynamic and stationary tests so that both the stationary coefficients and the flutter derivatives have been evaluated for each yaw angle. Specific free motion tests, taking advantage from the aeroelastic features of the section model, allowed also the study of the vortex shedding induced phenomena.

• 한국군사과학기술학회지
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• 제5권2호
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• pp.62-71
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• 2002

A free oscillation technique for obtaining the dynamic stability derivatives in yaw is applied to the pure yawing motion. The procedure of wind tunnel testing is to compute the derivatives after measuring deflecting angles of the model during the free oscillating motion. The charging compressed air is supplied for the initial excitation. The results of this experiment predicted feasible characteristics of the yawing motion, comparing with the data previously reported in the literature.

• 대한조선학회논문집
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• 제50권1호
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• pp.8-13
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• 2013

Excessive yaw motion of a turret moored vessel was examined in this paper. The vessel was moored by an internal turret and catenary mooring lines. The experiments were conducted in regular waves. Turret moored vessel can oscillate from side to side or move to one particular direction, and eventually exhibit large yaw motion. The results showed that the excessive yaw occured for specific condition, ratio of wave lengths and vessel length. It was found that turret moored floating vessel was unstable for regular wave period from 14 to 18 sec and excessive yaw occurred to maximum 50 deg. The time series, trajectory, phase plot and qualitative analysis are performed. The analysis showed that the results of experiments agreed with the that of analytic method and the excessive yaw could be predicted by the stability analysis.