Finite Element Modeling of Tires on Snow

Abstract

Vehicle movement on unpaved surfaces is important to military, agriculture, forestry, mining, construction, and recreation industries. Because of the complicated nature of vehicle-terrain interaction, comprehensive modeling of off-road mobility is often done using empirical algorithms. The desire to incorporate more physics into performance models has generated great interest in applying numerical modeling techniques in a full three-dimensional analysis, accounting for the deformation of both the tire and the terrain. In this study, a three-dimensional finite element model was constructed to simulate a tire rolling over snow. The snow was modeled as an inelastic material using critical-state constitutive modeling and plasticity theory. The snow material model was generated from experiments on the mechanical deformation of snow and was validated using a plate sinkage test. The tire models represent a range of sizes accommodating light-truck and off-road military vehicles and were rolled on snow of various depths. The combined tire-terrain models were validated using force measurements collected with instrumented vehicles and with measured snow deformation. The model results were also compared to vehicle mobility predictions made using the winter algorithms of the NATO Reference Mobility Model. These comparisons illustrate the agreement between the finite element models and field measurements of motion resistance forces and snow deformation under the tire.

Finite element simulation of the ski–snow interaction of an alpine ski in a carved turn

“…To overcome the condition that the ski has to be in a steady state, a dynamic simulation that includes a calculation of how the groove in the snow is formed would be necessary. Finite element simulations using modified Drucker-Prager or crushable foam element types might offer a means to realistically model the snow deformation [40,41]. The most challenging issue to solve will be the huge number of elements that would be required to model the ski-snow interaction and the formation of the groove: the actual snow deformation occurs on a scale of a few centimetres or millimetres, which requires a high resolution of the finite element lattice representing the snow, while for a simulation of a full turn a spatial range of about 20 m would be required.…”

Integration of ANCF continuum-based soil plasticity for off-road vehicle mobility in multibody system dynamics

“…For a summary of simulations composed of rigid and deformable tyres on soft terrain, see Shoop (2001) or Liu and Wong (1996). Examples of finite element-based simulation of wheeled terramechanics applications can be found in Grujicic et al (2009), Hambleton andDrescher (2009), Mohsenimanesh et al (2009), Nankali et al (2012, Pruiksma et al (2011), Shoop et al (2006), Xia (2011), and Xia and Yang (2012). For an example of a full vehicle on soft soil refer to Grujicic et al (2009).…”

Compaction-Based Deformable Terrain Model as an Interface for Real-Time Vehicle Dynamics Simulations

“…In the context of off-road vehicle simulations, terrain models fall into three categories of increasing complexity: rigid terrain where the main focus is an accurate surface profile [6][7][8][9], use of empirical relationships to find pressure and sinkage directly under the tire [10][11][12], or finite/discrete element approaches [13][14][15][16]. Any off-road vehicle dynamics simulation where the soil deforms considerably requires a terrain model that accurately reflects the deformation and response of the soil to all possible inputs of the tire in order to correctly simulate the response of the vehicle [17].…”