• International Journal of Precision Engineering and Manufacturing
• /
• 제5권4호
• /
• pp.50-60
• /
• 2004

A very flexible beam can be used to model various types of continuous mechanical parts such as cables and wires. In this paper, the dynamic properties of a very flexible beam, included in a multibody system, are analyzed using absolute nodal coordinates formulation, which is based on finite element procedures, and the general continuum mechanics theory to represent the elastic forces. In order to consider the dynamic interaction between a continuous large deformable beam and a rigid multibody system, a combined system equations of motion is derived by adopting absolute nodal coordinates and rigid body coordinates. Using the derived system equation, a computation method for the dynamic stress during flexible multibody simulation is presented based on Euler-Bernoulli beam theory, and its reliability is verified by a commercial program NASTRAN. This method is significant in that the structural and multibody dynamics models can be unified into one numerical system. In addition, to analyze a multibody system including a very flexible beam, formulations for the sliding joint between a very deformable beam and a rigid body are derived using a non-generalized coordinate, which has no inertia or forces associated with it. In particular, a very flexible catenary cable on which a multibody system moves along its length is presented as a numerical example.

• 대한기계학회논문집A
• /
• 제21권5호
• /
• pp.809-818
• /
• 1997

An efficient non-recursive formulation of dynamic force analysis has been developed for serially connected multibody systems. Although derivation of equations of motion is based on a recursive dynamic formulation with joint relative coordinates, in the proposed formulation, dynamic forces such as joint reaction forces and driving force are computed non-recursively for specified joints. The efficiency of the proposed formulation has been proved by the operational count and the CPU time measure, comparing with that of the conventional recursive Newton-Euler formulation. A simulation of 7-DOF RRC robot arm has been carried out to validate solutions of reaction forces by comparing with those from a commercial dynamic analysis program DADS.

• 한국자동차공학회논문집
• /
• 제18권1호
• /
• pp.44-50
• /
• 2010

Durability performance evaluation technology using Virtual Testing Method is a new concept of a vehicle design, which can reduce the automotive components design period and cost. In this paper, the fatigue life of an aluminum knuckle of a passenger car is evaluated using virtual testing method. The flexible multibody dynamic model of a front half car module is generated and solved with service loads which are measured from Belgian roads. Using a multibody dynamic analysis software, the flexible multibody dynamic simulation of a half car model is carried out and the dynamic stress profile of an aluminum knuckle is acquired. The stress profile is exported to a fatigue analysis software and durability performance of an aluminum knuckle is evaluated.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2008년도 추계학술대회A
• /
• pp.817-821
• /
• 2008

Wind turbine requires service life of about 20 years and each components of wind turbine requires high durability, because installation and maintenance costs are more expensive than generated electricity by wind turbine. So the design of wind turbine must be verified in various condition before production step. This paper demonstrates the application of a generic methodology, based on the flexible multibody simulation technique, for the dynamic analysis of a wind turbine and its drive train. The concern of the paper is the computation of dynamic loads of wind turbine in emergency-stop condition. The finite element model is used to analyse the dynamic behaviour of the wind turbine.

• International Journal of Precision Engineering and Manufacturing
• /
• 제4권6호
• /
• pp.50-60
• /
• 2003

A web-based dynamic simulation system, called O-DYN, for multibody systems is developed. All the interfaces of the system are accessible via web browsers, such as Netscape or Explorer. The system uses a block-diagram type O-DYN/Modeler developed in JAVA Applet as a preprocessor. The O-DYN postprocessor composed of O-DYN/Plotter and O-DYN/Animator is developed in JAVA Applet. The O-DYN/Solver for predicting the dynamic behavior is run on the web server. Anyone who wants to simulate the dynamics of multibody systems or share results data can access the analysis system over the internet regardless of their OS, platform, or location.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2009년도 추계학술대회 논문집
• /
• pp.611-612
• /
• 2009

• 대한기계학회논문집A
• /
• 제26권2호
• /
• pp.267-274
• /
• 2002

Using a flexible rotating beam test bed, experimental verification of a flexible multibody dynamic simulations for a rotating beam model has been carried out. The test bed consists of a flexible arm, harmonic driver reducer, AC servo motor and DSP board with PC. The mechanical ports of the test bed has been designed using 3D CAD program. For the simulation model, mass and moment of inertia of each part of the flexible rotating beam test bed are also obtained from 3D CAD model. In the flexible multibody dynamic simulations, the substructuring model has been established to capture nonlinear effects of the flexible rotating beam. Through the experimental verification, substructuring model provides better results than those from the linear model in the high speed rotation.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2008년도 춘계학술대회 논문집
• /
• pp.821-822
• /
• 2008

• 한국산업융합학회 논문집
• /
• 제20권5호
• /
• pp.405-410
• /
• 2017

This paper deals with 3D simulation of industrial robot for automated manufacturing system. In order to evaluate the operational characteristics of the industrial robot system in the worst case motion scenario, flexible - rigid multibody analysis was performed. Then, the rigid body dynamics analysis was performed and the results were compared with the flexible - rigid multibody analysis. Modal analysis was also performed to confirm the dynamic characteristics of the robot system. In the case of the flexible-rigid multibody simulation, only the structural members of interest were modeled as elastic bodies to confirm the stress state. The remaining structural members were modeled as rigid bodies to reduce computer resources.

• 한국정밀공학회지
• /
• 제20권6호
• /
• pp.160-166
• /
• 2003

Interest in advanced vehicles results in correspondingly increased interest in modeling and simulation of the dynamic behavior of Maglev-type vehicle systems. DADS is a program especially suited for the analysis of multibody mechanical systems. This paper demonstrates the application of DADS to the dynamic modeling and simulation of such advanced vehicles. A brief description is made of the modeling requirements of magnetically levitated systems, along with a summary of some of the related capabilities of DADS. As a case study, an analysis of a vehicle based on the UTM01 system is presented. This paper shows that the presented modeling technique is applicable to the dynamic characteristics evaluation and control law design of Maglev- type vehicles.