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Parallel methods for dynamic simulation of multiple manipulator systemsIn this paper, efficient dynamic simulation algorithms for a system of m manipulators, cooperating to manipulate a large load, are developed; their performance, using two possible forms of parallelism on a general-purpose parallel computer, is investigated. One form, temporal parallelism, is obtained with the use of parallel numerical integration methods. A speedup of 3.78 on four processors of CRAY Y-MP8 was achieved with a parallel four-point block predictor-corrector method for the simulation of a four manipulator system. These multi-point methods suffer from reduced accuracy, and when comparing these runs with a serial integration method, the speedup can be as low as 1.83 for simulations with the same accuracy. To regain the performance lost due to accuracy problems, a second form of parallelism is employed. Spatial parallelism allows most of the dynamics of each manipulator chain to be computed simultaneously. Used exclusively in the four processor case, this form of parallelism in conjunction with a serial integration method results in a speedup of 3.1 on four processors over the best serial method. In cases where there are either more processors available or fewer chains in the system, the multi-point parallel integration methods are still advantageous despite the reduced accuracy because both forms of parallelism can then combine to generate more parallel tasks and achieve greater effective speedups. This paper also includes results for these cases.
Document ID
19940010164
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Mcmillan, Scott
(Ohio State Univ. Columbus, OH, United States)
Sadayappan, P.
(Ohio State Univ. Columbus, OH, United States)
Orin, David E.
(Ohio State Univ. Columbus, OH, United States)
Date Acquired
September 6, 2013
Publication Date
February 15, 1993
Publication Information
Publication: JPL, Proceedings of the Fifth NASA(NSF)DOD Workshop on Aerospace Computational Control
Subject Category
Computer Systems
Accession Number
94N14637
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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