Dirt Late Model Race Car Simulations with Dymola and Modelica

This document explores the development of a high-fidelity Dirt Late Model (DLM) race car simulation model using Dymola, Modelica, and the VeSyMA Motorsports library to investigate the relationship between suspension setup changes, handling characteristics, and lap time performance.

The research integrates multibody vehicle dynamics, suspension kinematics, quasi-static track simulations, virtual rig testing, and track replay analysis to study how setup adjustments influence vehicle behaviour under varying track conditions. Despite limited access to accurate physical test data, the simulations successfully replicated realistic on-track behaviour and enabled detailed investigation of factors such as steering response, weight transfer, suspension non-linearities, and handling hypersensitivity to lap time changes. The study demonstrates how predictive simulation tools can support race car setup optimisation, driver feedback analysis, and performance development while reducing reliance on expensive physical testing and prototyping.