Dan Negrut

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SUMMARY We present two methods for efficiently sampling the response (trajectory space) of multibody systems operating under spatial uncertainty, when the latter is assumed to be representable with Gaussian processes. In this case, the dynamics (time evolution) of the multibody systems depends on spatially indexed uncertain parameters that span infinite(More)
The premise of this work is that the presence of high stiffness and/or frictional contact/impact phenomena limits the effective use of high order integration formulas when numerically investigating the time evolution of real-life mechanical systems. Producing a numerical solution relies most often on low order integration formulas of which the paper(More)
The paper presents theoretical and implementation aspects related to a numerical integrator used for the simulation of large mechanical systems with flexible bodies and contact/impact. The proposed algorithm is based on the Hilber-Hughes-Taylor implicit method and is tailored to answer the challenges posed by the numerical solution of index 3(More)
This paper has not been submitted elsewhere in identical or similar form, nor will it be during the first three months after its submission to Multibody System Dynamics. Abstract. When performing dynamic analysis of a constrained mechanical system, a set of index 3 differential algebraic equations (DAE) describes the time evolution of the model. This paper(More)
When performing dynamic analysis of a constrained mechanical system, a set of index three differential-algebraic equations (DAE) describes the time evolution of the system. The paper presents a state space based method for the numerical solution of the resulting DAE. A subset of so-called independent generalized coordinates, equal in number to the number of(More)
This document highlights aspects related to the support and use of unified, or managed, memory in CUDA 6. The discussion provides an opportunity to revisit two other CUDA memory transaction topics: zero-copy memory and unified virtual addressing. The latter two can be regarded as intermediary milestones in a process that has led in CUDA 6 to the release of(More)
In the context of simulating the frictional contact dynamics of large systems of rigid bodies, this paper reviews a novel method for solving large cone complementarity problems by means of a fixed-point iteration algorithm. The method is an extension of the Gauss-Seidel and Gauss-Jacobi methods with overrelaxation for symmetric convex linear complementarity(More)
In this paper, a new method to efficiently compute accelerations and Lagrange multipliers in the equations of multibody dynamics is presented. These quantities are the solution of a system of linear equations whose coefficient matrix has the special structure of an optimization matrix. This matrix is likely to have a large number of zero entries, according(More)
This paper describes a numerical method for the parallel solution of the differential measure inclusion problem posed by mechanical multibody systems containing bilateral and unilateral frictional constraints. The method proposed has been implemented as a set of parallel algorithms leveraging NVIDIA's Compute Unified Device Architecture (CUDA) library(More)
This paper describes an approach for the dynamic simulation of complex computer-aided engineering models where large collections of rigid bodies interact mutually through millions of frictional contacts and bilateral mechanical constraints. Thanks to the massive parallelism available on to-day's GPU boards, we are able to simulate sand, granular materials,(More)