Skip to content
Free planNo credit card requiredStart writing
AI for Research home
AI for Research home
Dashboard
Sign inGet started

Search 250 million research papers

Read the abstract, see who wrote it and who cites it, and get the citation in APA, MLA, Chicago or Harvard.

About 4,550 papers for “Multibody system”

Multibody System Dynamics

Heo, Seundo, Bauchau, Olivier · Rare & Special e-Zone (The Hong Kong University of Science and Technology) · 2014

Cited by 0

Multibody System Dynamics

Ekansh Chaturvedi, Adrian Sandu, Corina Sandu · VTechWorks (Virginia Tech) · 2023

The conventional approach of simulating multibody dynamic systems treats the joint interfaces as ideal, that means that the bodies are in absolute alignment with each other in the desired relative directions of motion. However, in real life systems the clearances between the bodies allow the bodies to undergo a certain misalignment and the dynamics is governed by the contacts thus formed. Contact detection and evaluation of contact forces is yet another problem that needs to be addressed. Popular approaches assume the Hertzian nature of the contact and thus evaluate contact forces using nonlinear unilateral spring-damper elements. This approach results in very stiff differential algebraic equations and hence make the numerical integration computationally expensive. Furthermore, the Hertzian approach does not address truly elastic or truly inelastic nature of the contact. This work describes the parametric formulations for fundamental spatial joints with clearances and the non-smooth dynamics approach to solve the resulting equations of motion. The sets of spatial joint expressions for cylindrical, prismatic and revolute joints, and the non-smooth dynamics formulations are derived, considering their interdependence with great care. Further, the nature of the contact with clearances is discussed. The formulation is demonstrated through three case-studies and a detailed analysis of the results is presented. Additionally, a differentiation with respect to the ideal joint counterpart of the revolute joint case study is presented using tangent space ordinary differential equation formulation.

Cited by 0Open access

Multibody System Simulation with SimMechanics

Michael Schlotter · 2003

This paper describes, how to simulate the dynamics of multibody systems with SimMechanics, a toolbox for the Matlab / Simulink envi-ronment. The novel Physical Modeling method is compared with tra-ditional ways to represent mechanical systems in Matlab, and some in-teresting mathematical aspects of the implementation of SimMechanics are examined. 1

Cited by 0

Model Reduction for Multibody System

Stefano Gamba · Research Padua Archive (University of Padua) · 2009

In the first part of this thesis we presents a computationally fast mathematical model of a motorcycle drivetrain, that can be implemented in a multibody motorcycle model for handling and maneuverability studies and long time-scale analysis. Given a mathematical model of the primary drive and the transmission, possessing an arbitrary number of shafts, we define a reduced model composed by only two counter-rotating shafts of suitable masses and inertias. Also, we show how forces and torques applied to the original model must be adapted to the compact one, in order for the two systems to be indistinguishable with respect to energy transfer and gyroscopic moments. Beyond the simplification of the equations due to the reduced number of bodies, another advantage of this model is that, once the equations of motion are derived, any n-shaft transmission can be simulated just changing the equation parameters, without the need of recompiling the whole multibody model. In the second part of the dissertation the modeling of the drive chain is discussed. A multibody model of the rear half of a motorcycle is described, to reproduce the fast dynamics caused by the chain models with high stiffness. Applying a quasi-steady-state approximation of the extension of the chain, we effectively eliminates the undesired high frequencies vibrations, and preserving the slow signals that most influence the trajectory of the vehicle. The only drawback of this solution is the need of solving a nonlinear equation with two unknowns to evaluate the reduced equations of motion. The problem is overcome with another reduction method, that is enforcing holonomic constraints on the lengths of the upper and lower chain segments. In order to do that without loosing two degrees of freedom, the stiff nonlinear model is first described as a switched model where the chain segments are replaced by linear springs. Then, the submodels are reduced separately and merged together to obtain the overall reduced model. An intelligent formulation of the constraints let us derive the chain tension even if its extension is constantly zero.

Cited by 0Open access

Coupling multibody system and granular dynamics

Lantsoght, Olivier, Fisette, Paul, Dubois, Frédéric et al. · Digital Access to Libraries (Université catholique de Louvain (UCL), l'Université de Namur (UNamur) and the Université Saint-Louis (USL-B)) · 2017

We present a benchmark to experimentally validate the method we have developed to simulate mechanical devices interacting with granular media. Consequently the method we develop is able to solve problems involving bilateral and unilateral constraints. The mechanical device is modelled with the multibody system approach and is described by the use of relative coordinates. With these coordinates, the bilateral constraints are mainly due to loop-closure conditions (or specific bilateral constraints such as imposed screw-joint motion). The bilateral constraints are solved thanks to the coordinate partitioning method. The problem of contact dynamics, which introduces the unilateral constraints, is solved by a non-linear Gauss-Seidel procedure applied in the contacts coordinates. The procedure accounts for the constrained motion of the mechanism because the coordinate partitioning is also applied to the mapping between the contacts coordinates and the generalized coordinates. Consequently the solution of the unilateral constraints problem is locally compatible with the set of bilateral constraints coming from the mechanical system. The proposed planar benchmark consists of a modified four-bar mechanism blending a set of disks contained in a vibrating box. The numerical results reveals the influence of the vibration frequency on the granular compactness and thus the mechanism motion.

Cited by 0Open access

A system identification procedure for multibody system dynamics

Askari Renani, Ehsan, Crevecoeur, Guillaume · Ghent University Academic Bibliography (Ghent University) · 2021

The governing equations of multibody system dynamics are discovered directly from time-series datasets of a given mechanism using an evolutionary symbolic sparse regression approach without any prior knowledge of the respective mechanism. For the discovery of physical models, a dictionary of basis functions is used, a risk of which is that the dictionary is not large enough to discover the physical laws. This risk is mitigated by following an exploration-exploitation strategy to evolutionarily build and validate the function dictionaries, for which a symbolic sparse regression method based on genetic programming is developed. Illustrative examples are finally considered to demonstrate the capability of the presented approach to distilling the governing equations.

Cited by 0Open access

Constraint Embedding for Multibody System Dynamics

Abhinandan Jain · NASA Technical Reports Server (NASA) · 2009

This paper describes a constraint embedding approach for the handling of local closure constraints in multibody system dynamics. The approach uses spatial operator techniques to eliminate local-loop constraints from the system and effectively convert the system into tree-topology systems. This approach allows the direct derivation of recursive O(N) techniques for solving the system dynamics and avoiding the expensive steps that would otherwise be required for handling the closedchain dynamics. The approach is very effective for systems where the constraints are confined to small-subgraphs within the system topology. The paper provides background on the spatial operator O(N) algorithms, the extensions for handling embedded constraints, and concludes with some examples of such constraints.

Cited by 0

Multibody system dynamics driven product processes

Qasim Khadim · LUTPub (LUT University) · 2021

Sustainable business models emphasize the application of digital solutions to enhance customer value throughout the product lifecycle. This dissertation contributes to the development of methods that integrate multibody-dynamics-driven digital solutions with the product lifecycle and enable investigation of the technical aspects associated with the user experience in real-time simulation applications. To this end, real-time simulation methods are studied for hydraulically driven multibody applications. Academic examples are included that take a monolithic approach to investigate the optimal simulation methods. A parameter estimation algorithm is also proposed to estimate linear and non-linear product parameters to solve the field-related problems. The scope of this work includes the real-time simulation application of the multibody formulation in a real-world example of an industrial mobile 3W counterbalance 2.0-t EVOLT48 electric forklift. The user experience is analyzed with respect to customer value. Regarding the technical aspects of the user experience, the multibody simulation model is coupled with human-in-loop simulators and virtual reality tools to study and analyze the user experience via test users. Further, through a multibody-based digital twin, tools and methods are studied to integrate the user experience into various phases of the product lifecycle to enhance customer value. The results of this dissertation may enable companies to enhance customer value through multibody-based digital twins and generate sustainable business models in an eco-friendly environment.

Cited by 1

Analytical Derivatives For Multibody System Analyses

Al Ys Es, Radu Serban, Edward J. Haug · 1988

Analytical formulas for kinematic and kinetic derivatives needed in multibody system analyses are derived. A broad spectrum of problems, including implicit numerical integration, dynamic sensitivity analysis, and kinematic workspace analysis, require evaluation of first derivatives of generalized inertia and force expressions and at least three derivatives of algebraic constraint functions. In the setting of a formulation based on Cartesian generalized coordinates with Euler parameters for orientation, basic identities are developed that enable practical and efficient computation of all derivatives required for a large number of multibody mechanical system analyses. The formulation is verified through application to to a spatial slider crank mechanism and a 14 body vehicle model. Efficiency of computation using the expressions derived is compared with results obtained employing finite differences, showing significant computational advantage using the analytically derived expressions. 1...

Cited by 0