Contact Modelling in Co-simulation of Mechanical Systems Using Model Order Reduction

EasyChair Preprint 13480

Abstract

There are different ways to account for contact interactions in a mechanical system; each approach has its own advantages and disadvantages. In this work, we aim to compare two different contact modelling possibilities in a co-simulation setup. Co-simulation involves the simultaneous simulation of multiple interconnected physical systems using different simulation tools. The process of a co-simulation involves defining the interface between different subsystems and exchanging interface variables between them at specific communication points called macro time steps. To determine the variables at the interface between the communication points, we consider two model-based modellings which involve creating a reduced interface model (RIM) of the mechanical system to mimic the behaviour of the full model at the interface. The first method, the smooth RIM, assumes that the contact state will remain unchanged during the macro time step. The second method, the non-smooth RIM, involves identifying potential contact pairs and accounting for them through the solution of a linear complementarity problem during the time step, allowing for the possibility of contact attachments or detachments between communication points. Using a robotic arm as an example, it was found that the smooth RIM can produce inaccurate results in certain cases. One solution to this issue is to regularize some of the constraints by adding constitutive relations, but that can change the physics the model represents, and determining the proper stiffness and damping coefficients can be challenging. In contrast, the non-smooth RIM was found to produce results that were more accurate and in line with the reference solution without changing the system model.

Keyphrases: Contact modelling, Dynamics of mechanical systems, Model Order Reduction, co-simulation

@booklet{EasyChair:13480,
  author    = {Ali Raoofian and Xu Dai and Jozsef Kovecses},
  title     = {Contact Modelling in Co-simulation of Mechanical Systems Using Model Order Reduction},
  howpublished = {EasyChair Preprint 13480},
  year      = {EasyChair, 2024}}