ANCF Tire Assembly Model for Multibody System Applications

Abstract

The aim of this paper is to propose a new numerical approach for modeling tires in multibody system (MBS) applications. In this approach, the tires, including the rigid rim, are modeled using one mesh developed using the finite element (FE) absolute nodal co-ordinate formulation (ANCF). The FE tire mesh, which allows for high spinning speed, has a constant inertia matrix and zero Coriolis and centrifugal forces. The connectivity conditions between the tire tread and rim are imposed at a preprocessing stage using linear constraint equations, thereby allowing for the elimination of dependent variables before the start of the simulation. The concept of the rim node is introduced in this paper to allow for the tire/axle assembly in MBS vehicle simulations. The rim node, which is not associated with a particular FE, is used to define the inertia of the rim, treated in this investigation as a rigid body. The procedure for evaluating the inertia coefficients associated with the rim node gradients is described. It is shown how fully parameterized ANCF beam and plate elements can be used to develop new tire geometry that captures details that cannot be captured using existing tire models. The concept of mixed ANCF FEs can also be used with both higher order fully parameterized and gradient deficient ANCF FEs to obtain a better distribution of the tire contact forces.