Integration of Finite Element and Multibody Dynamics Models Using Gluing Algorithm

2009 ◽  
Author(s):  
Geunsoo Ryu ◽  
Zheng-Dong Ma ◽  
Gregory M. Hulbert
Keyword(s):  
Finite Element ◽  
Reference Frame ◽  
Elastic Deformation ◽  
Multibody Dynamics ◽  
Information Exchange ◽  
Distributed Simulation ◽  
Body Motion ◽  
Flexible Body ◽  
Flexible Multibody ◽  
Gluing Algorithm

This paper provides a method of the coupling multibody dynamics (MBD) and finite element (FE) codes to solve flexible multibody dynamics problems across a distributed simulation platform. The aim is to minimize the information exchange across the different platforms yet still obtain results of engineering accuracy. Many approaches for solving flexible multibody systems consisting of elastic and rigid components have focused on how the equations of motion for the flexible components can be formulated and combined with other component equations. We present a Partitioned Iteration Method (PIM), which can decouple the elastic deformation and rigid body motion of the flexible body by employing a CG-following floating reference frame. In the PIM, the global motion of a flexible body is expressed as a summation of the linearized elastic deformation measured in the CG-following reference frame and the motion of the reference frame and be solved in separated finite element and multibody dynamics solvers. The PIM is combined with the gluing algorithm and is used to solve multiple flexible bodies in a distributed simulation environment. It enables the use of independent simulation servers, where each server can run commercially available or research-based MBD and/or FE solvers. Examples are provided to demonstrate the performance of the new method and to show how to decouple and integrate a general flexible multi-body dynamics system.

A Partitioned Iteration Method Employing CG-Following Reference Frames for Distributed Simulation of Flexible Multibody Systems

2007 ◽  
Author(s):  
Geunsoo Ryu ◽  
Zheng-Dong Ma ◽  
Gregory M. Hulbert
Keyword(s):  
Rigid Body ◽  
Elastic Deformation ◽  
Iteration Method ◽  
Multibody Systems ◽  
Distributed Simulation ◽  
Rigid Body Motion ◽  
Flexible Multibody Systems ◽  
Body Motion ◽  
Flexible Multibody ◽  
Gluing Algorithm

A distributed simulation platform, denoted as D-Sim, has been developed previously by our research group, which comprises three essential attributes: a general XML description for models suitable for both leaf and integrated models, a gluing algorithm, which only relies on the interface information to integrate subsystem models, and a logical distributed simulation architecture that can be realized using any connection-oriented distributed technology. The overarching research focus is to integrate heterogeneous subsystem models, e.g., multibody dynamics subsystems models and finite element subsystems models and to conduct seamlessly integrated simulation and design tasks in a distributed computing environment. A Partitioned Iteration Method (PIM) is proposed in this paper, which decouples the rigid body motion from elastic deformation of the simulated system using an iteration scheme. The method employs a CG-following reference frame for each deformable body in the distributed simulation of flexible multibody systems. The resultant simulation system can be used to integrate distributed deformable bodies D-Sim, while allowing large rigid body motions among the bodies or subsystems. It also enables using independent simulation servers; where each server can run commercially available or research-based MBD and/or FEM codes. Examples are provided that demonstrate the performance of the method and also how to decouple and integrate rigid body motion and elastic deformation using the developed gluing algorithm.

Performance of the Incremental and Non-Incremental Finite Element Formulations in Flexible Multibody Problems

1999 ◽  
Vol 122 (4) ◽  
pp. 498-507 ◽  
Author(s):  
Marcello Campanelli ◽  
Marcello Berzeri ◽  
Ahmed A. Shabana
Keyword(s):  
Finite Element ◽  
Multibody Systems ◽  
Absolute Nodal Coordinate Formulation ◽  
Flexible Multibody Systems ◽  
Large Displacement ◽  
Body Motion ◽  
Absolute Nodal Coordinate ◽  
Flexible Multibody ◽  
The Absolute ◽  
Finite Element Formulations

Many flexible multibody applications are characterized by high inertia forces and motion discontinuities. Because of these characteristics, problems can be encountered when large displacement finite element formulations are used in the simulation of flexible multibody systems. In this investigation, the performance of two different large displacement finite element formulations in the analysis of flexible multibody systems is investigated. These are the incremental corotational procedure proposed in an earlier article (Rankin, C. C., and Brogan, F. A., 1986, ASME J. Pressure Vessel Technol., 108, pp. 165–174) and the non-incremental absolute nodal coordinate formulation recently proposed (Shabana, A. A., 1998, Dynamics of Multibody Systems, 2nd ed., Cambridge University Press, Cambridge). It is demonstrated in this investigation that the limitation resulting from the use of the infinitesmal nodal rotations in the incremental corotational procedure can lead to simulation problems even when simple flexible multibody applications are considered. The absolute nodal coordinate formulation, on the other hand, does not employ infinitesimal or finite rotation coordinates and leads to a constant mass matrix. Despite the fact that the absolute nodal coordinate formulation leads to a non-linear expression for the elastic forces, the results presented in this study, surprisingly, demonstrate that such a formulation is efficient in static problems as compared to the incremental corotational procedure. The excellent performance of the absolute nodal coordinate formulation in static and dynamic problems can be attributed to the fact that such a formulation does not employ rotations and leads to exact representation of the rigid body motion of the finite element. [S1050-0472(00)00604-8]

Flexible Multibody Dynamics Formulation by Hamilton’s Equations

2010 ◽  
Author(s):  
Martin M. Tong
Keyword(s):  
Multibody Dynamics ◽  
Multibody System ◽  
Mass Matrix ◽  
Equations Of Motion ◽  
Flexible Multibody Dynamics ◽  
Flexible Body ◽  
Flexible Multibody System ◽  
Generalized Coordinates ◽  
Flexible Multibody ◽  
The Matrix

Numerical solution of the dynamics equations of a flexible multibody system as represented by Hamilton’s canonical equations requires that its generalized velocities q˙ be solved from the generalized momenta p. The relation between them is p = J(q)q˙, where J is the system mass matrix and q is the generalized coordinates. This paper presents the dynamics equations for a generic flexible multibody system as represented by p˙ and gives emphasis to a systematic way of constructing the matrix J for solving q˙. The mass matrix is shown to be separable into four submatrices Jrr, Jrf, Jfr and Jff relating the joint momenta and flexible body mementa to the joint coordinate rates and the flexible body deformation coordinate rates. Explicit formulas are given for these submatrices. The equations of motion presented here lend insight to the structure of the flexible multibody dynamics equations. They are also a versatile alternative to the acceleration-based dynamics equations for modeling mechanical systems.

Flexible Multibody Dynamics Based on a Fully Cartesian System of Support Coordinates

1993 ◽  
Vol 115 (2) ◽  
pp. 294-299 ◽  
Author(s):  
N. Vukasovic ◽  
J. T. Celigu¨eta ◽  
J. Garci´a de Jalo´n ◽  
E. Bayo
Keyword(s):  
Multibody Dynamics ◽  
Reference Frames ◽  
Deformable Body ◽  
Equations Of Motion ◽  
Flexible Multibody Dynamics ◽  
Body Motion ◽  
Cartesian System ◽  
Flexible Multibody ◽  
Local Reference ◽  
Rigid Multibody

In this paper we present an extension to flexible multibody systems of a system of fully cartesian coordinates previously used in rigid multibody dynamics. This method is fully compatible with the previous one, keeping most of its advantages in kinematics and dynamics. The deformation in each deformable body is expressed as a linear combination of Ritz vectors with respect to a local frame whose motion is defined by a series of points and vectors that move according to the rigid body motion. Joint constraint equations are formulated through the points and vectors that define each link. These are chosen so that a minimum use of local reference frames is done. The resulting equations of motion are integrated using the trapezoidal rule combined with fixed point iteration. An illustrative example that corresponds to a satellite deployment is presented.

Incremental Finite Element Formulations and Flexible Multibody Dynamics

1999 ◽  
Author(s):  
Marcello Berzeri ◽  
Marcello Campanelli ◽  
A. A. Shabana
Keyword(s):  
Finite Element ◽  
Multibody Dynamics ◽  
Multibody Systems ◽  
Absolute Nodal Coordinate Formulation ◽  
Flexible Multibody Dynamics ◽  
Flexible Multibody Systems ◽  
Large Displacement ◽  
Absolute Nodal Coordinate ◽  
Flexible Multibody ◽  
Finite Element Formulations

Abstract In this investigation, the performance of two different large displacement finite element formulations in the analysis of flexible multibody systems is investigated. These are the incremental corotational procedure proposed by Rankin and Brogan [8] and the non-incremental absolute nodal coordinate formulation recently proposed [9]. It is demonstrated in this investigation that the limitation resulting from the use of the nodal rotations in the incremental corotational procedure can lead to simulation problems even when very simple flexible multibody applications are considered.

Finite Element Method of Flexible Multibody Dynamics Based on a New Kind of Floating Frame

1991 ◽  
Author(s):  
You-Fang Lu ◽  
Zhao-Hui Qi ◽  
Bin Wang ◽  
Guan-Min Feng
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Numerical Analysis ◽  
Multibody Dynamics ◽  
Equations Of Motion ◽  
Flexible Multibody Dynamics ◽  
Flexible Multibody ◽  
Floating Frame ◽  
Element Method

Abstract A new kind of floating frame whose parameters do not appear in equations of motion as additional unknowns is defined. Numerical analysis of flexible multibody dynamics is much facilitated by using finite-element iteration of the corresponding equations based on this concept.

Sign in / Sign up

Export Citation Format

Share Document