• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.4
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• pp.450-455
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• 1986

본 연구에서는 직교좌표계 및 Euler-Lagrange 방법을 이용하여 유도된 기본 방정식을 사용하여 앞창닦기기구(windshield wiper mechanism)의 동력학적 해석을 하 였다.모우터가 일정한 각속도로 회전하고 있는 경우와, 토오크가 각속도의 크기에 따라 변화하는 경우 각각에 대해서 강체로 해석할 때와 탄성체로 가정할 때의 해석결 과를 비교하였다.

• Journal of Ocean Engineering and Technology
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• v.21 no.1 s.74
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• pp.69-74
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• 2007

This paper is concerned about the dynamic analysis of an underwater test miner, which operates on cohesive soil. The test miner consists of tracked vehicles and a pick-up device. The motion of the pick-up device, relative to the vehicle chassis, is controlled by two pairs of hydraulic cylinders. The test miner is modeled by means of commercial software. A terramechanics model of cohesive soft soil is implemented with the software and applied to a dynamic analysis of the test miner model. The dynamic responses of the test miner are studied with respect to four different types of terrain conditions.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.10
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• pp.705-711
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• 2019

Dynamic behaviors of the deployable composite reflector antenna are numerically and experimentally investigated. Equations of the motion are formalized using Kane's equation by considering multibody systems with two degrees of freedom such as folding and twisting angles. To interpret structural deformations of the reflector antenna, the composite reflector is modeled using a beam model with the FSDT(First-order Shear Deformation Theory). To determine design parameters such as a torsional spring stiffness and a damping coefficient depending on deployment duration, an inverted pendulum model is simply applied. Based on the determined parameters, dynamic characteristics of the deployable reflector are investigated. In addition, its results are verified and compared through deployment tests using a gravity compensation device.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.130-131
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• 2011

In the present work, a synchronization test system for variable nozzle is described. Variable nozzles are used to enhance the effectiveness of aircraft engines at various altitudes. The synchronization test system was developed to verify the dynamic characteristics and synchronization of variable nozzle mechanism including flaps. The system with a variable nozzle was analyzed, before its fabrication, by a multi-body dynamics analysis software RecurDyn. The newly developed test system is being used to show the synchronization capability of a variable nozzle system.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.37.1-37.1
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• 2011

A floating wind turbine dynamic simulation program, 'WindHydro', is newly developed. In order to investigate the characteristics of the program, a series of loading cases are simulated such as (1) wind only case, (2) free decay cases with initial displacement, (3) wave only case (4) wind and wave case. The simulations are carried out for the 5-MW OC3-Hywind model which has a spar buoy and catenary mooring lines. As a result, the reliability of WindHydro is verified in most viewpoints although additional study is still necessary to clear out some uncertainty of the program.

• Journal of the Korean Society of Propulsion Engineers
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• v.13 no.3
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• pp.41-49
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• 2009

The present paper describes a mathematical modeling and simulation of the separation of a solid rocket booster from an air breathing engine vehicle. The vehicle and booster are considered as a multi-connected body and the booster is assumed to move only along the axial direction of the vehicle. The dynamic motion of the vehicle and the booster were modeled by using Kane's method. The aerodynamic forces on the whole system along various positions of booster were calculated by using DATCOM software and the internal pressure force acting on the effective surface during separation was simply calculated with gas dynamics and Taylor MacColl equation. Numerical simulation was done by using Mathworks-Matlab. From the result, the variation of Mach number and angle of attack are not large during the separation, so the variation of pitch angle and the characteristics of inlet flow for varying the Mach number and angle of attack during the separation test can be identified as neglectable values.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.180.2-180.2
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• 2010

Simulation technology for dynamic analysis of wind turbine is developed. The Aerodyn and the DAFUL are chosen for aerodynamic analysis and multi-body and flexible body dynamics respectively. Subroutines and variables of Aerodyn developed by NREL are analyzed with hub-height wind data, full field turbulent wind data and Airfoil data. The interface to perform coupled analysis between AeroDyn and DAFUL, GUI for modeling several parts of wind turbines are developed. The program will be extended to analyze the coupled analysis of aerodynamic and hydrodynamic behavior for floating offshore wind turbines.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.11
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• pp.176-184
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• 2000

Recently, it becomes a very important issue to consider the mechanical systems such as high-speed vehicle and railway train moving on a flexible beam structure. Using general approach proposed in the first part of this paper, it tis possible to predict planar motion of constrained mechanical system and elastic structure with various kinds of foundation supporting condition. Combined differential-algebraic equations of motion derived from both multibody dynamics theory and Finite Element Method can be analyzed numerically using generalized coordinate partitioning algorithm. To verify the validity of this approach, results from simply supported elastic beam subjected to a moving load are compared with exact solution from a reference. Finally, parameter study is conducted for a moving vehicle model on a simply supported 3-span bridge.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.11
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• pp.165-175
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• 2000

In recent years, it becomes a very important issue to consider the mechanical systems such as high-speed vehicles and railway trains moving on elastic beam structures. In this paper, a general approach, which can predict the dynamic behavior of constrained mechanical system and elastic beam structure, is proposed. Also, various supporting conditions of a foundation support are considered for the elastic beam structures. The elastic structure is assumed to be a nonuniform and linear Bernoulli-Euler beam with proportional damping effect. Combined Differential-Algebraic Equations of motion are derived using multibody dynamics theory and Finite Element Method. The proposed equations of motion can be solved numerically using generalizd coordinate partitioning method and Predictor-Corrector algorithm, which is an implicit multi-step integration method.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.3
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• pp.177-183
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• 2004

The out-of-positioned small female drivers are most likely to be injured during airbag deployment due to their stature and proximity to the steering wheel and airbag module. In order to investigate the injury mechanisms, some experimental studies with Hybrid III 5% female dummy and with female cadavers could be found from the open literatures. However, the given information from those experimental studies is quite limited to the standard conditions and might not be enough to estimate the airbag inflation aggressiveness regarding on the occupant responses and injury. In this study, a finite element analysis has been performed in order to investigate the airbag-induced injuries. A finite element 5% female human model in anatomical details has been developed. The validation results of the model are also introduced in this paper.