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NASA NTRS · 20140012750

An Efficient Solution Method for Multibody Systems with Loops Using Multiple Processors

Abstract

This paper describes a multibody dynamics algorithm formulated for parallel implementation on multiprocessor computing platforms using the divide-and-conquer approach. The system of interest is a general topology of rigid and elastic articulated bodies with or without loops. The algorithm divides the multibody system into a number of smaller sets of bodies in chain or tree structures, called "branches" at convenient joints called "connection points", and uses an Order-N (O (N)) approach to formulate the dynamics of each branch in terms of the unknown spatial connection forces. The equations of motion for the branches, leaving the connection forces as unknowns, are implemented in separate processors in parallel for computational efficiency, and the equations for all the unknown connection forces are synthesized and solved in one or several processors. The performances of two implementations of this divide-and-conquer algorithm in multiple processors are compared with an existing method implemented on a single processor.

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BibTeXRIS

Tushar K Ghosh, Luong A Nguyen, Leslie J Quiocho. 2015-04-09. An Efficient Solution Method for Multibody Systems with Loops Using Multiple Processors. https://ntrs.nasa.gov/citations/20140012750

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