• 대한기계학회논문집
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• 제17권10호
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• pp.2543-2554
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• 1993

In this paper, the kinematic and dynamic analyses of spatial complex kinematic chain are studied. Through the new method both using the set of identification numbers and applying the DenavitHartenberg link representation method to the spatial complex kinematic chain, the kinematic configuration of the chain is represented. Some link in the part of closed chain being fictitiously cutted, the complex kinematic chain is transformed to the branched chain. The kinematic constraint equations are derived from the constraint conditions which the cutted sections of the link have to satisfy. And the joint variables being partitioned in the independent joint variables and the dependent joint variables, the dependent variables are calculated from the independent variables by using the Newton-Raphson iterative method and the pseudoinverse matrix. The equations of motion are derived under the independent joint variables by using the principle of virtual work. Algorithms for dynamic analysis are presented and simulations are done to verify accuracy and efficiency of the algorithms.

• 대한기계학회논문집A
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• 제20권11호
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• pp.3398-3407
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• 1996

In this paper, we derive an algorithm and develope a computer program which analyze rapidly and precisely the inverse kinematics of robotic mechanism with spatial complex chain structure based on the relative coordinates. We represent the inverse kinematic problem as an optimization problem with the kinematic constraint equations. The inverse kinematic analysis algorithm, therefore, consists of two algorithms, the main, an optimization algorithm finding the motion of independent joints from that of an end-effector and the sub, a forward kinematic analysis algorithm computing the motion of dependent joints. We accomplish simulations for the investigation upon the accuracy and efficiency of the algorithm.

• 대한의용생체공학회:의공학회지
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• 제20권4호
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• pp.485-493
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• 1999

Human can generate various posture and motion with nearly 350 muscle pairs. From the viewpoint of mechanisms, the human skeleton mechanism represents great kinematic and dynamical complexity. Physical and behavioral fidelity of human motion requires dynamically accurate modeling and controling. This paper describes a mathematical modeling, and dynamic simulation of human body. The human dynamic model is simplified as a rigid body consisting of 18 actuated degrees of freedom for the real time computation. Complex kinematic chain of human body is partitioned as 6 serial kinematic chains that is, left arm, right arm, support leg, free leg, body, and head. Modeling is developed based on Newton-Euler formulation. The validity of proposed dynamic model, which represents mathematically high order differential equation, is verified through the dynamic simulation.

• 천문학회보
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• 제44권2호
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• pp.75.4-75.4
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• 2019

We present a quantitative analysis of the relationship between the gas dynamics and star formation history of DDO 210 which is an irregular dwarf galaxy in the local Universe. We perform profile analysis of an high-resolution neutral hydrogen (HI) data cube of the galaxy taken with the large Very Large Array (VLA) survey, LITTLE THINGS using newly developed algorithm based on a Bayesian Markov Chain Monte Carlo (MCMC) technique. The complex HI structure and kinematics of the galaxy are decomposed into multiple kinematic components in a quantitative way like 1) bulk motions which are most likely to follow the underlying circular rotation of the disk, 2) non-circular motions deviating from the bulk motions, and 3) kinematically cold and warm components with narrower and wider velocity dispersion. The decomposed kinematic components are then spatially correlated with the distribution of stellar populations obtained from the color-magnitude diagram (CMD) fitting method. The cold and warm gas components show negative and positive correlations between their velocity dispersions and the surface star formation rates of the populations with ages of < 40 Myr and 100~400 Myr, respectively. The cold gas is most likely to be associated with the young stellar populations. Then the stellar feedback of the young populations could influence the warm gas. The age difference between the populations which show the correlations indicates the time delay of the stellar feedback.