• 설비공학논문집
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• 제11권5호
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• pp.605-614
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• 1999

Orbiting scroll mass center is different from the basic circle's for the normal involute profile. As for the orbiting scroll balanced conditions, the dynamic modeling are set up. The influences on sealing, reaction forces between the moving elements and forces from the moving elements to the compressor frame are analyzed in this paper. The simulation and experiment results are presented.

• 한국소음진동공학회논문집
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• 제13권8호
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• pp.605-611
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• 2003

A simply supported pipe conveying fluid and two moving masses upon it constitute this nitration system. The equation of motion is derived by using Lagrange's equation. The influence of the velocities of two moving masses, the distance between two moving masses, and the velocities of fluid flow in the pipe have been studied on the dynamic behavior of a simply supported pipe by numerical method. The velocities of fluid flow are considered with in its critical values of a simply supported pipe without moving masses upon It. Their coupling effects on the transverse vibration of a simply supported pipe are inspected too. As the velocity of two moving masses increases, the deflection of a simply supported pipe is increased and the frequency of transverse vibration of a simply supported pipe is not varied. In case of small distance between two masses, the maximum deflection of the pipe occur when the front mass arrive at midspan. Otherwise as the distance get larger, the position of the front masses where midspan deflection is maximum moves beyond the midpoint of a simply supported pipe. The deflection of a simply supported pipe is increased by coupling of the velocities of moving masses and fluid flow.

• Structural Engineering and Mechanics
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• 제28권4호
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• pp.491-494
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• 2008

• 동력기계공학회지
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• 제12권6호
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• pp.50-55
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• 2008

In general, the swing motion of the crane is controlled and suppressed by activating the trolley motion. In many papers reported by us, we suggested a new type of anti-sway control system of the crane. In the proposed control system, a small auxiliary mass(moving-mass) is installed on the spreader and the swing motion is controlled by moving the auxiliary mass. The actuator reaction against the auxiliary mass applies inertial control forces to the container in order to reduce the swing motion in the desired manner. Futhermore the measuring systems based on image sensor have been proposed also. To obtain the robustness for our control system, $H_{\infty}$ based control techniques and other approach have been applied to suppress swing motion. As well known, the robust control technologies based on $H_{\infty}$ control need complicated and difficult process. In the result, the obtained closed-loop system becomes to high order system which may give us many difficulties to apply it to the real plants. Therefore, we introduce an easy approach which is based on LQ control theory. In this approach, we introduce the frequency dependent weighting matrices which give the system filters to shape frequency characteristics of the controlled system and guarantee the control performance.

• 동력기계공학회지
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• 제11권4호
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• pp.103-108
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• 2007

In general, the swing motion of the crane is controlled and suppressed by activating the trolley motion. In many papers reported by us, we suggested a new type of anti-sway control system of the crane. In the proposed control system, a small auxiliary mass(moving-mass) is installed on the spreader and the swing motion is controlled by moving the auxiliary mass. The actuator reaction against the auxiliary mass applies inertial control forces to the container in order to reduce the swing motion in the desired manner. The measuring system is based on laser sensor or others. However it is not so useful in real world. Especially, in this paper, the image sensor is used to measures the motions of the spreader and the measured data are fed back to the controller in real time. The applied image processing technique is a kind of robust template matching method which is named Vector Code Correlation (VCC) and devised to consider the real environmental conditions. And the $H_{\infty}$ based control technique is applied to suppress swing motion of the crane. And the experimental result shows that the proposed measurement system based on image sensor and control system is useful and robust to disturbances.

• 전력전자학회논문지
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• 제11권2호
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• pp.159-163
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• 2006

선형 서보 응용분야에서 속도제어기를 정밀하게 조정하기 위해서는 부하 및 가동자의 질량을 항상 정확하게 알고 있어야 한다. 본 논문에서는 선형 영구자석 동기전동기의 가동부 질량을 추정하기 위하여 상수추정 알고리즘으로 최소자승법을 적용한 질량 추정방법을 제안하였다. 먼저 최소자승법을 적용하기 위한 기계적인 동전 시스템에 대한 DARMA(deterministic autoregressive moving average)모델을 유도하고, 유도된 DARMA모델에 최소자승법을 적용한 시뮬레이션 덴 실험 결과를 제시하여 제안한 방법으로 질량을 정밀하게 추정할 수 있음을 보였다.

• 대한기계학회논문집
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• 제15권1호
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• pp.61-68
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• 1991

본 연구에서는 스프링힌지, 클램프, 단순지지, 탄성지반, 다수의 병진 및 회 전스프링 그리고 중간지지점의 조합으로 구성되어 있는 보에 대하여 우선 Hamilton원 리에 의하여 정확한 보의 특성방정식을 유도하고 모든 경계조건을 만족하는 직교다항 식을 구한 후, 스프링, 댐퍼로 구성된 여러개의 질량이 일정한 속도로 이동할 경우에 대하여 Galerkin방법과 수치적분 방법을 사용하여 동적응답을 구하였다. 또한 구속 조건 및 경계조건이 변함에 따라 동적응답에 미치는 영향을 연구하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.826-831
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• 2005

In this paper the effect of moving mass on dynamic behavior of cracked cantilever beam on elastic foundations is presented. Based on the Euler-Bernoulli beam theory, the equation of motion can be constructed by using the Lagrange's equation. The crack section is represented by a local flexibility matrix connecting two undamaged beam segments. That is, the crack is modelled as a rotational spring. This flexibility matrix defines the relationship between the displacements and forces across the crack section and is derived by applying fundamental fracture mechanics theory. The crack is assumed to be in the first mode of fracture. As the depth of the crack is increased, the tip displacement of the cantilever beam is increased. When the crack depth is constant the frequency of a cracked beam is proportional to the spring stiffness.

• 한국소음진동공학회논문집
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• 제15권10호
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• pp.1195-1201
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• 2005

In this paper, the effect of a moving mass on dynamic behavior of the cracked cantilever beam on elastic foundations is presented. Based on the Euler-Bernoulli beam theory, the equation of motion can be constructed by using the Lagrange's equation. The crack section is represented by a local flexibility matrix connecting two undamaged beam segments. That is, the crack is modelled as a rotational spring. This flexibility matrix defines the relationship between the displacements and forces across the crack section and is derived by applying fundamental fracture mechanics theory The crack is assumed to be in the first mode of fracture. As the depth of crack is increased, the tip displacement of the cantilever beam is Increased. When the depth of crack is constant, the frequency of a cracked beam is proportional to the spring stiffness.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.958-963
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• 2003

In this paper a dynamic behavior of simply supported cracked pipe conveying fluid with the moving mass is presented. Based on the Timoshenko beam theory, the equation of motion can be constructed by using the Lagrange's equation. The crack section is represented by a local flexibility matrix connecting two undamaged beam segments i.e. the crack is modelled as a rotational spring. This flexibility matrix defines the relationship between the displacements and forces across the crack section and is derived by applying fundamental fracture mechanics theory. And the crack is assumed to be in th first mode of fracture. As the depth of the crack and velocity of fluid are increased the mid-span deflection of the pipe conveying fluid with the moving mass is increased. As depth of the crack is increased, the effect that the velocity of the fluid on the mid-span deflection appears more greatly.