Accession Number : ADA625087


Title :   A Planar Quasi-Static Constraint Mode Tire Model


Corporate Author : ARMY TANK AUTOMOTIVE RESEARCH DEVELOPMENT AND ENGINEERING CENTER WARREN MI


Personal Author(s) : Ma, Rui ; Ferris, John B ; Reid, Alexander A ; Gorsich, David


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a625087.pdf


Report Date : 10 Jul 2015


Pagination or Media Count : 13


Abstract : The world of vehicle design is a fast-paced iterative environment that demand s efficiency in the simulation of suspension loads. Toward that end, a computationally efficient, linear, planar, quasi-static tire model is developed in this work that accurately predicts a tire s lower-frequency, reasonably large amplitude, nonlinear stiffness relationship. Hamilton s principle is used to derive the axisymmetric and circumferentially isotropic stiffness equation which is discretized into segments to create the tire stiffness model. The model is parameterized by a single stiffness parameter and two shape parameters such that the tire s deformed shape is completely independent of the overall tire stiffness and the forces acting on the tire. Constraint modes are developed that capture the tire enveloping and bridging properties via component mode synthesis originated by Hurty and Gladwell and the Guyan static reduction method decouples active constraints from the stiffness matrix formulation . A recursive method is developed to deduce the set of active constraints at the tire-road interface. The model captures the nonlinear stiffness of a real tire by enforcing the unidirectional geometric boundary conditions during the recursive method. The model parameters are identified via two quasi-static experiments: a flat-plate and a cleat test. The simulated vertical loads are within 4% of the experimental load throughout a reasonably large range of travel for the flat-plate test and within 7% of the experimental loads for the cleat test. The simulation produces nonlinear stiffness when simulating a flat plate test and a discontinuous stiffness when simulating a cleat test. This model strikes a balance between simple tire models that lack the fidelity to make accurate chassis load predictions and computationally intensive models that cannot provide timely predictions.


Descriptors :   *TIRES , ACCURACY , AMPLITUDE , AXISYMMETRIC , BALANCE , CHASSIS , EFFICIENCY , EQUATIONS , FORMULATIONS , ISOTROPISM , MATRICES(MATHEMATICS) , MODELS , NONLINEAR SYSTEMS , PARAMETERS , PLANAR STRUCTURES , PLATES , PREDICTIONS , RECURSIVE FUNCTIONS , REDUCTION , SHAPE , SIMULATION , STATICS , STIFFNESS , SYNTHESIS , TEST AND EVALUATION , UNIDIRECTIONAL , VERTICAL ORIENTATION


Subject Categories : Surface Transportation and Equipment


Distribution Statement : APPROVED FOR PUBLIC RELEASE