• 제목/요약/키워드: Flexible dynamics

검색결과 406건 처리시간 0.028초

부분시스템 합성방법을 이용한 심해저 통합 채광시스템의 효율적인 유연 다물체 동역학 모델링 연구 (A Study on the Efficient Flexible Multibody Dynamics Modeling of Deep Seabed Integrated Mining System with Subsystem Synthesis Method)

  • 윤홍선;김성수;이창호;김형우
    • 대한기계학회논문집A
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    • 제39권12호
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    • pp.1213-1220
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    • 2015
  • 망간단괴를 채집하는 심해저 통합 채광시스템은 채광선, 수직양광관, 중간버퍼, 유연관, 채광로봇으로 구성되어 있다. 최근 심해저 통합 채광시스템 연구에서는 생산성을 극대화하기 위한 다수의 채광로봇으로 구성되는 새로운 다중로봇 통합 채광시스템의 개념이 소개되었다. 본 논문에서는 다중로봇 통합 채광시스템 해석의 효율성을 향상시키고, 다중로봇 시스템의 확장이 이하도록 부분시스템 합성방법이 적되었다. 또한 유연 다물체 동역학이 적된 부분구조로 나눔으로써 수직양광관과 유연관의 대변위가 고려되었다. 일반적인 해석방법과 부분시스템 합성방법의 산술 연산 횟수를 비교함으로써 통합 채광시스템의 부분시스템 합성방법의 이론적인 효율성 연구가 수행되었다.

다관절 유연 로보트 팔의 역동력학 해석 (Inverse dynamic analysis of flexible robot arms with multiple joints)

  • 김창부;이승훈
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.254-259
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    • 1992
  • In this paper, we propose an optimal method for the tracking a trajectory of the end-effector of flexible robot arms with multiple joints. The proposed method finds joint trajectories and joint torques necessary to produce the desired end-effector motion of flexible manipulator. In inverse kinematics, optimized joint trajectories are computed from elastic equations. In inverse dynamics, joint torques are obtained from the joint equations by using the optimized joint trajectories. The equations of motion using finite element method and virtual work principle are employed. Optimal control is applied to optimize joint trajectories which are computed in inverse kinematics. The simulation of flexible planner manipulator is presented.

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탄성 대변형 다물체동역학을 위한 슬라이딩조인트 개발 (The Development of a Sliding Joint for Very Flexible Multibody Dynamics)

  • 서종휘;정일호;수기야마;사바나;박태원
    • 대한기계학회논문집A
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    • 제29권8호
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    • pp.1123-1131
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    • 2005
  • In this paper, a formulation for a spatial sliding joint, which a general multibody can move along a very flexible cable, is derived using absolute nodal coordinates and non-generalized coordinate. The large deformable motion of a spatial cable is presented using absolute nodal coordinate formulation, which is based on the finite element procedures and the general continuum mechanics theory to represent the elastic forces. And the non-generalized coordinate, which is neither related to the inertia forces nor external forces, is used to describe an arbitrary position along the centerline of a very flexible cable. In the constraint equation for the sliding joint, since three constraint equations are imposed and one non-generalized coordinate is introduced, one constraint equation is systematically eliminated. Therefore, there are two independent Lagrange multipliers in the final system equations of motion associated with the sliding joint. The development of this sliding joint is important to analyze many mechanical systems such as pulley systems and pantograph/catenary systems for high speed-trains.

지지구조와 액츄에이터의 유연성을 고려한 HDD 유연 회전 디스크-스핀들 시스템의 유한 요소 고유 진동 해석 (Finite Element Modal Analysis of a Spinning Flexible Disk-Spindle System Considering the Flexiblity of Supporting Structures and an Actuator in a HDD)

  • 서찬희;이창석;장건희;이호성
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.330-336
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    • 2005
  • This paper presents a method to analyze the vibration of a flexible spinning disk-spindle system with FDBs, flexible base structure and an actuator in a HDD by using the FEM. Finite element equations of each component of a HDD spindle system from the spinning flexible disk to the flexible base plate are consistently derived by satisfying the geometric compatibility in the internal boundary between each component. A global matrix equation obtained by assembling the finite element equations of each substructure is transformed to a state-space matrix-vector equation, and both damped natural frequencies and modal damping ratios are calculated by using the restarted Arnoldi iteration method. The validity of the proposed method is verified by comparing the simulated natural frequencies, mode shapes with the experimental results.

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Numerical investigation on pressure responsiveness properties of the skirt-cushion system of an air cushion vehicle

  • Xu, Shengjie;Tang, Yujia;Chen, Kejie;Zhang, Zongke;Ma, Tao;Tang, Wenyong
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제12권1호
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    • pp.928-942
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    • 2020
  • The pressure responsiveness property of a skirt-cushion system, which is closely related to the overall performance of Air Cushion Vehicles (ACVs), has always been the difficulty and challenging problem involving cushion aerodynamics and flexible skirt dynamics. Based on a widely used bag and finger skirt-cushion system, the pressure responsiveness properties are investigated numerically. The physical process and mechanism are analyzed and a numerical method for evaluating the pressure responsiveness property is proposed. A cushion-skirt information communication platform is also presented for interchanging the force and the skirt configuration between cushion aerodynamics and flexible skirt dynamics. The pressure responsiveness of a typical skirt-cushion system is calculated and the results demonstrate that the pressure responsiveness property helps alleviate the influence of the cushion height changing on the overall performance of ACVs. Finally, the influences of skirt geometrical and cushion aerodynamic parameters on the pressure responsiveness properties are discussed systematically, giving insight into the design of skirt-cushion systems.

정밀한 파지를 할 수 있는 로봇 손의 안정성 평가 (Safety Design analysis of a Robot Hand for Accurate Grasping Various Objects)

  • 이민규;이용훈;임홍재;이용권
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2007년도 추계학술대회논문집
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    • pp.1203-1210
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    • 2007
  • Robots have begun to perform various tasks on replacing the human in the daily life such as cleaning, entertainments etc. In order to accomplish the effective performance of intricate and precise tasks, robot hand must have special capabilities, such as decision making in given condition, autonomy in unknown situation and stable manipulation of object. In this study, we addresses the development of a 3-fingered humanoid robot hand system. We execute static analysis, vibration analysis and flexible dynamics to reserve stability at the design. Grasp motion of the finger uses a linear actuator and gears. Motion can be distinguished into four parts depending on the grasping thin paper, sphere, and column. In each motion, we compare the displacement of the case to be rigid with the case to be flexible. As a result, manufactured and feasibility of the robot hand is validated through preliminary experiments.

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Dynamic Analysis of a Moving Vehicle on Flexible beam Structure (II) : Application

  • Park, Tae-Won;Park, Chan-Jong
    • International Journal of Precision Engineering and Manufacturing
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    • 제3권4호
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    • pp.64-71
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    • 2002
  • Recently, mechanical systems such as a high-speed vehicles and railway trains moving on flexible beam structures have become a very important issue to consider. Using the general approach proposed in the first part of this paper, it is possible to predict motion of the constrained mechanical system and the elastic structure, with various kinds of foundation supporting conditions. Combined differential-algebraic equation of motion derived from both multibody dynamics theory and finite element method can be analyzed numerically using a generalized coordinate partitioning algorithm. To verify the validity of this approach, results from the simply supported elastic beam subjected to a moving load are compared with the exact solution from a reference. Finally, parametric study is conducted for a moving vehicle model on a simply supported 3-span bridge.

역학을 이용한 탄성 로보트 아암의 선단 위치 제어 기어에 대한 연구 (A Study on the Position Control Improvement of Flexible Robot Arm by Inverse Dynamics)

  • 방두열;이성철
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1997년도 춘계학술대회 논문집
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    • pp.9-13
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    • 1997
  • This parer is a study on the inverse dynamics of a one-link flexible robot arm which is controlled by translational base motion. The system is composed of a flexible arm, a base for driving arm, a DC servomotor, and a computer. The arm base is moved so that the arm tip follows a desired function. The governing equations are based on the Bernoullie-Euler beam theory and solved by applying the Laplace transform method and then the numerical inversion method. Moter voltage is obtained by simulation for tip trajectory functions i. e. Bang-Bang, Cosine and Gauss Function. And, the tip motion is measured while simulation results are applying. Then the results are investigated to select most proper input and to compare their chateristics. Experimental results show the Cosine function is most proper with respect to low maximum voltage and steady state error.

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보행 보조 로봇의 설계 및 개발 (Walking Assistance Robot Design and Development)

  • 이민규;이용훈;임홍재;이용권
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2008년도 춘계학술대회논문집
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    • pp.585-592
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    • 2008
  • The aging society comes, the number of the old people expended. Technical aids allow elderly and handicapped people to live independently in their private homes as long as they wish. As a contribution to these required technological solutions, a demonstrator platform for a walking assistance robot. robot which has the capability to perform fetch and carry and various other supporting tasks. In this study, we addresses the development of a walking assistance robot system. We execute static analysis, vibration analysis and flexible dynamics to reserve stability at the design. Each motion of the robot uses a linear actuator and gears. Motion can be distinguished into 3 parts depending on the up & down, rotation, and cushion trans. In each motion, we compare the displacement of the case to be rigid with the case to be flexible. As a result, manufactured and feasibility of the walking assistance robot is validated through preliminary experiments.

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