Admissible Shape Parameters for a Planar Quasi-Static Constraint Mode Tire Model

Abstract : The interaction between the tire and terrain has long been of interest for vehicle dynamic simulation. Detailed tire models produce accurate results, but are too computationally intensive for the iterative vehicle design process. The objective of this work is to develop a computationally efficient way to estimate the tire's deformed shape, from which the tire forces can be evaluated. A novel, planar, quasi-static, constraint mode tire model is developed to address this objective. The required model parameters are reduced to two non-dimensional shape parameters and an overall stiffness factor. An admissible domain of the shape parameters is developed based on the deformation limitations of a physical tire. Specifically, no single harmonic may dominates the tire shape and the low spatial frequency components must contribute more than higher frequency components to the overall tire shape. The ability of the model to accurately predict the spindle force is evaluated by comparing simulation and experimental responses for quasi-static flat plate and cleat tests. This work provides a simple, accurate tire model for circumferential displacement and vertical spindle force prediction to improve the vehicle design process.