Nonlinear Structural Mechanics

In this field of activity we deal with the modeling and simulation of highly deformable components and structures such as tyres, rubber bushings, air springs, cables and hoses. Different levels of modeling are covered, ranging from computationally expensive continuum mechanical FE models to simplified macroscopic models with high performance.

It is crucial to choose the 'optimal model complexity' according to the intended application. A model must contain sufficient details to display the relevant physical effects and yet fulfill effort requirements imposed by the development process.

In this context, new mathematical methods of model reduction are developed to describe the complex behavior of a structure (e.g. a tyre) in MBS context with rather few degrees of freedom. Commercial software like Abaqus or AmeSim is employed as well as in-house developments based on Matlab or C++.

Interactive Simulation of Cables and Hoses

Versorgungsschläuche in IPS Cable Simulation
© Photo ITWM

Supply hoses in IPS Cable Simulation

Virtual assembly planning requires a fast and physically correct description of the behavior of cables and hoses like the ones used to operate robot arms.

In close cooperation with the "Fraunhofer-Chalmers Research Centre for Industrial Mathematics FCC", the software package IPS was developed allowing the interactive simulation of cables and hoses in real-time.

Model Reduction for Elastomer Bushings

Physikalische Modellierung eines Luftfedersystems
© Photo ITWM

Physical model of an air suspension system

For the inclusion of nonlinear suspension systems such as rubber bushings or air springs, MBS modeling frequently relies on surrogate formulations based on spring characteristics. This description is insufficient for the behavior of the component.

Methods of model reduction are able to include complex structures under dynamic loading into a full system while maintaining its nonlinearity.

Example Projects

 

Joint project SNiMoRed

SNiMoRed is a joint project of five mathematical institutes and two companies, set within the automotive industry, about multidisciplinary simulation, nonlinear model reduction and proactive control for vehicle dynamics.

 

Joint project GeoMec

The focus of the research work is the development of discrete geometric structure models for VAR applications that utilize physics based modeling and simulation of elastic structures.

 

MAVO project EMMA-CC

The main objective of the project is the development of an enhanced digital human model (DHM) for ergonomic assessment of realistic dynamic motions.