Using Flexible Constraints to Reduce Noise in Multibody Systems With Intermittent Contact

The application of multibody dynamics software has extended to mechanical systems with hundreds of bodies and/or hundreds of contacts. Examples include gear trains, chains on sprockets and guides, belts on pulleys, and flexible body meshes in contact with each other. These types of models frequently have intermittent contacts and contact friction that can be the source of numerical noise. This noise produces large and rapidly fluctuating force outputs that may concern the engineer, particularly when attempting to design a component or perform a failure analysis. Rigid joints are often selected to constrain the bodies undergoing intermittent contact in order to minimize the degrees of freedom (DOFs) in the model. This paper demonstrates that the use of properly-tuned flexible constraints (bushings) and contacts can significantly reduce the noise in simple and complex models with intermittent and reversing contact.Copyright © 2007 by ASME