Scale model investigation of the snaking and folding stability of an articulated frame steer vehicle

This paper describes the development and evaluation of an articulated frame steer, scale model vehicle. Vehicles with articulated steering are known to exhibit unstable behaviour in the form of snaking or folding instabilities when operated at high speed, as previously studied using analytical models, simulations and full vehicle tests. The aim of this study is to design a scaled test vehicle that is able to reproduce unstable modes found in articulated vehicles. The model vehicle may provide greater insight than simulations, while avoiding the costs and hazards associated with full vehicle tests. The objective is also to investigate how well a linearised planar model and eigenvalue analysis can predict vehicle stability properties. Experimental and theoretical results have been critically analysed, and found to exhibit typical full vehicle behaviour. The linear mathematical model exhibited similar trends when compared to the scale model test results.