> For the complete documentation index, see [llms.txt](https://2025.istvs.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://2025.istvs.org/submissions/papers/4335.md).

# 4335 - EXTENDED BRUSH MODEL FOR USE WITH GRAVELLY TERRAIN

{% hint style="info" %}
Paper presented at ISTVS 2025 | 55th Conference of the International Society for Terrain-Vehicle Systems <https://doi.org/10.56884/>
{% endhint %}

**Authors:** *Devon Cox, P. Schalk Els*

**Keywords:** Extended brush tyre model; Off road mobility; Agricultural tyres; Tyre soil interaction; Model validation

**Abstract:**

This paper presents the development of a physics-based brush tyre model extended for applications beyond conventional smooth surfaces. The research addresses limitations in existing tyre models when simulating vehicle dynamics on non-smooth, hard terrain. A comprehensive literature survey informed the methodological approach, which combines a physics-based brush model with empirical tread and soil models implemented in MATLAB. Initial validation results demonstrate promising performance, indicating that the combination of empirical soil characterization with the physics-based brush model effectively predicts tyre forces on non-smooth terrain. The model provides a framework for predicting traction limits in off-road conditions, expanding the simulation capabilities for vehicle dynamics on complex surfaces.


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