Development and Implementation of a Hybrid Soft Soil Tire Model (HSSTM)

摘要

In order to model the dynamic behavior of pneumatic tires on soft soil, a hybrid (lumped mass – brush model) discretized model was developed (HSSTM). This model can be easily linked with multibody dynamics software packages to simulate vehicle performance on deformable terrains. To optimize the computational time, different techniques were used in memory allocation, parameter initialization, code sequence, and multi-processing, which made the code run close to real time. The tire parameterization was performed using a reduced finite element tire model, modal analysis, and experimental testing. In the parameterization step, sensitivity analysis tools were incorporated in order to reduce the complexity of the model and to fit more accurate parameter values based on the test data. Experimental tests on sandy loam were performed on the Terramechanics rig in the Advanced Vehicle Dynamics Laboratory at Virginia Tech. Data collected included tire spindle force and moments, soil sinkage, and tire deformation data. This data, in addition to modal analysis data, was used for model validation. Furthermore, simulations at conditions similar to the test conditions were performed on a quarter car model. The results have indicated the superiority of this model as compared to other lumped parameter models currently available.