Radial-Interradial Spring Tyre Model for Dynamic Analysis of Maximum Loads During Obstacle Interaction

Sammanfattning

Modern tillage machines have increased considerably in size and weight while often lacking active suspension systems. As a result, accurate estimation of peak loads is essential for structural design and to reduce reliance on costly physical testing. To determine the loads acting on the wheel assemblies, a tyre model describing the behaviour of the tyre is therefore required. A literature review of tyre modelling approaches was conducted, and a radial–interradial spring model was developed based on a trade-off between computational efficiency and accuracy. The tyre is represented using discretised spring and damping elements and formulated as a two-dimensional dynamic system governed by the equations of motion and implemented in Matlab. Experimental data from test rigs and full-scale obstacle-crossing tests with a single-axle trailer were used for model calibration and validation. The calibrated tyre model was integrated into a trailer model to evaluate load responses during obstacle interaction. In addition, results from the trailer model were used as input to a finite element model in Abaqus to analyse more complex dynamic behaviours. The models were able to reasonably predict tyre behaviour and vertical loads during obstacle interaction, including peak loads significantly exceeding static conditions. Despite simplifying assumptions, the approach provides a computationally efficient tool for early-stage design and reduces the need for physical prototyping. However, the models are limited in their abilities to capture more complex dynamic behaviour, and more advanced modelling approaches are required for such analyses.