A Gluing Algorithm for Network-Distributed Multibody Dynamics Simulation

The improved performance and capacity of networks has made thecombined processing power of workstation clusters a potentiallypromising avenue for solving computationally intensive problems acrosssuch distributed environments. Moreover, networks provide an idealplatform to employ heterogeneous hardware and software to solvemultibody dynamics problems. One fundamental difficulty with distributedsimulation is the requirement to couple and synchronize the distributedsimulations. This paper focuses on the algorithms necessary to coupletogether separately developed multibody dynamics modules so that theycan perform integrated system simulation. To identify a useful couplingstrategy, candidate numerical algorithms in the literature are reviewedbriefly – namely, stiff time integration, local parameterization,waveform relaxation, stabilized constraint and perturbation. Anunobtrusive algorithm that may well serve this `gluing' role ispresented. Results from numerical experiments are presented and theperformance of the gluing algorithm is investigated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43264/1/11044_2004_Article_352676.pd

An Efficient Newton-Type Iteration for the Numerical Solution of Highly Oscillatory Constrained Multibody Dynamic Systems

In this paper we present a coordinate-split (CS) technique for the numerical solution of the equations of motion of constrained multibody dynamic systems. We show how the coordinate-split technique can be implemented within the context of commonly used solution methods, for increased efficiency and reliability. A particularly challenging problem for multibody dynamics is the numerical solution of highly oscillatory nonlinear mechanical systems. Highly stable implicit integration methods with large stepsizes can be used to damp the oscillation, if it is of small amplitude. However, the standard Newton iteration is known to experience severe convergence difficulties which force a restriction of the stepsize. We introduce a modified coordinate-split (CM) iteration which overcomes these problems. Convergence analysis explains the improved convergence for nonlinear oscillatory systems, and numerical experiments illustrate the effectiveness of the new method. The work was partially spons..