Design and manufacturing of a demonstrator of the tyre brush model

Abstract

The tyre brush model is widely used to describe tyre-road interaction, but physical demonstrations are uncommon. A real-world demonstrator was therefore developed to improve understanding of how tyre elements deform in the longitudinal direction under different operating conditions, including the formation of slip in the contact region. A structured engineering design process was applied, including concept development and evaluation using systematic methods. The final system consists of a rotating wheel with flexible bristles and a moving belt representing the ground surface. The demonstrator is driven by electric motors and controlled using an Arduino-based system with motor drivers, allowing adjustment of operating conditions such as relative speed. This makes it possible to illustrate different slip scenarios in a clear and repeatable way. The developed demonstrator partially visualises the intended real-world behaviour and represents a first step toward an educational tool for improving intuitive understanding of the tyre brush model. However, the demonstrator does not fully reproduce the expected brush model behaviour, as the bristles fail to continuously increase their deformation along the contact zone. Instead, they straighten toward the middle of the contact patch, which deviates from theoretical predictions. Despite this, certain key behaviours - such as increased bristle deformation at higher slip ratios and full loss of traction at low speed correlations - are observable. Future work is needed to address these shortcomings before the demonstrator can be used reliably as an educational tool.