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PubMed · 15376839

A generalized framework for interactive dynamic simulation for MultiRigid bodies.

Wookho Son·Kyunghwan Kim·Nancy M Amato·Jeffrey C Trinkle
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Abstract

This paper presents a generalized framework for dynamic simulation realized in a prototype simulator called the Interactive Generalized Motion Simulator (I-GMS), which can simulate motions of multirigid-body systems with contact interaction in virtual environments. I-GMS is designed to meet two important goals: generality and interactivity. By generality, we mean a dynamic simulator which can easily support various systems of rigid bodies, ranging from a single free-flying rigid object to complex linkages such as those needed for robotic systems or human body simulation. To provide this generality, we have developed I-GMS in an object-oriented framework. The user interactivity is supported through a haptic interface for articulated bodies, introducing interactive dynamic simulation schemes. This user-interaction is achieved by performing push and pull operations via the PHANToM haptic device, which runs as an integrated part of I-GMS. Also, a hybrid scheme was used for simulating internal contacts (between bodies in the multirigid-body system) in the presence of friction, which could avoid the nonexistent solution problem often faced when solving contact problems with Coulomb friction. In our hybrid scheme, two impulse-based methods are exploited so that different methods are applied adaptively, depending on whether the current contact situation is characterized as "bouncing" or "steady." We demonstrate the user-interaction capability of I-GMS through on-line editing of trajectories of a 6-degree of freedom (dof) articulated structure.

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AlgorithmsBiomechanical PhenomenaComputer SimulationHumansJointsModels, BiologicalMovementNonlinear DynamicsRoboticsUser-Computer InterfaceEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Wookho Son, Kyunghwan Kim, Nancy M Amato, Jeffrey C Trinkle. 2004. A generalized framework for interactive dynamic simulation for MultiRigid bodies.. https://doi.org/10.1109/tsmcb.2003.818434

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