Mathematical models for farm tractor rollover prediction

Abstract

This paper deals with the estimation of the rollover limit of a farm tractor. The rollover phenomenon is investigated by considering the static stability of the farm tractor on a sloped surface. Three mathematical models are derived to understand the basic features of the rollover mechanism. The models are able to predict the (static) rollover limit for any orientation of the farm tractor with respect to the slope. The effects of tyre stiffness (vertical and lateral) and nonsymmetric implement positioning are analysed. The classical architecture of the farm tractor equipped with a pivoting front axle is compared with the adoption of a passively suspended front axle. In case of a front axle suspension, the rollover limit of the vehicle can be improved, especially when employing non-symmetric implements.