• Title/Summary/Keyword: 편속도행렬

Search Result 7, Processing Time 0.021 seconds

An Optimization Algorithm to Compute Pre-Loads of the Given Static Equilibrium State in Train Dynamics (열차동역학에서 주어진 정적평형상태의 초기하중을 계산하기 위한 최적화 알고리즘)

  • 김종인;박정훈;유홍희;황요하
    • Journal of the Korean Society for Railway
    • /
    • v.2 no.3
    • /
    • pp.9-17
    • /
    • 1999
  • This paper presents a new algorithm to determine the pre-loads that sustain the static equilibrium state in a given position. The algorithm which uses a partial velocity matrix leads to an unconstrained optimization problem to compute the pre-loads of the suspensions. To demonstrate the validity of the proposed algorithm, the static analysis results that employ the pre-loads of three examples are presented using a reliable commercial program. Results of the analysis confirm the validity of the proposed algorithm.

  • PDF

Dynamic analysis of constrained multibody systems using Kane's method (케인방법을 이용한 구속 다물체계의 동역학 해석)

  • Park, Jeong-Hun;Yu, Hong-Hui;Hwang, Yo-Ha;Bae, Dae-Seong
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.21 no.12
    • /
    • pp.2156-2164
    • /
    • 1997
  • A new formulation for the dynamic analysis of constrained multibody systems is presented in this paper. The formulation employs Kane's method along with the null space method. Kane's method reduces the dimension of equations of motion by using partial velocity matrix introduced in this study : it can improve the efficiency of the formulation. Three numerical examples are given to demonstrate the accuracy and efficiency of the formulation.

Static equilibrium and linear vibration analysis of a high speed electric train system (고속전철 시스템의 정적평형 및 선형진동 해석)

  • 김종인;유홍희;황요하
    • Journal of the Korean Society for Railway
    • /
    • v.2 no.4
    • /
    • pp.1-8
    • /
    • 1999
  • A formulation to perform static equilibrium and linear vibration analysis is presented in this paper. The formulation employs minimum number of equations of motion which are derived by using a partial velocity matrix. The static equilibrium analysis is performed first, then the linear vibration analysis is performed at the static equilibrium position. By using the formulation presented in this paper, static equilibrium and linear vibration analysis of a high speed electric train system are performed. A single bogie system, a power car vehicle, and a train system which consists of five vehicles are analyzed, respectively. Natural frequencies and a few lowest mode shapes of the two are identified in this paper.

  • PDF

Dynamic Analysis of Multibody Systems Undertaking Impulsive Force using Kane's Method (충격하중을 받는 시스템의 케인 방법을 이용한 다물체 동역학 해석)

  • 김상국;박정훈;유홍희
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.6 no.3
    • /
    • pp.169-176
    • /
    • 1998
  • A method for the dynamic analysis of multibody systems undertaking impulsive force is introduced in this paper. A partial velocity matrix based on Kane's method is introduced to reduce the number of equations to be solved. Only minimum number of equations of motion can be obtained by using the partial velocity matrix. This reduces the computational effort significantly to obtain the dynamic response of the system. At the very moment of the impulse, instead of using the numerical integrator to solve the equations of motion, the impulse and momentum principle is used to obtain the dynamic response. The impulse as wall as the reaction force acting on the kinematic joints can easily calculated too.

  • PDF

Multibody Dynamics Analysis for Contacting Rigid Bodies (접촉하는 강체간의 다물체 동역학 해석)

  • Park, Jeong-Hun;Hwang, Yo-Ha;Yu, Hong-Hui
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.24 no.2 s.173
    • /
    • pp.411-420
    • /
    • 2000
  • This paper presents a new method for calculating contact position and contact force. The proposed method calculates accurate contact position by introducing intermediate parameters. Accurate contac t force can be obtained by solving reduced equations of motion iteratively. This method can be applied to calculate not only contact force on contact points but also contact force on kinematic joints such as a rotational joint and a translational joint. Four numerical examples are given to demonstrate the effectiveness of the proposed algorithm.

Dynamic Analysis of Constrained Multibody Systems Undergoing Collision (충돌하는 구속 다물체계의 동역학 해석)

  • Park, Jeong-Hun;Yu, Hong-Hui;Yang, Hyeon-Ik;Hwang, Yo-Ha
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.24 no.2 s.173
    • /
    • pp.535-542
    • /
    • 2000
  • This paper presents a method for the dynamic analysis of constrained multibody systems undergoing abrupt collision. The proposed method uses a longer time interval to check collision than that of c onventional method. This reduces the computational effort significantly. To calculate collision points on two colliding rigid bodies, one may introduce constraints of contact. However, this causes reduction of degree of freedom and difficulty of numerical analysis. The proposed method can calculate collision points without above mentioned problems. Three numerical examples are given to demonstrate the computational efficiency and the usefulness of the proposed method.

Partitioning method using kinematic uncoupling in train dynamics (열차 동역학에서 기구학적 비연성을 이용한 분할 해석 방법)

  • Park, J.H.;Yoo, H.H.;Hwang, Y.H.;Kim, C.H.
    • Journal of the Korean Society for Railway
    • /
    • v.2 no.1
    • /
    • pp.47-55
    • /
    • 1999
  • In this paper, an efficient and accurate formulation for the transient analysis of constrained multibody systems is presented. The formulation employs Kane's method along with the null space method. Kane's method reduces the dimension of equations of motion by using partial velocity matrix: it can improve the efficiency of the formulation. Furthermore, the formulation partitions the coefficient matrix of linear and nonlinear equations into several sub-matrices using kinematic uncoupling. This can solve the equations more efficiently. The proposed formulation can be used to perform dynamic analysis of systems which can be partitioned into several sub-systems such as train systems. One numerical example is given to demonstrate the efficiency and accuracy of the formulation, and another numerical example is given to show its application to the train systems.

  • PDF