Static modelling and stability analysis of non-slewing articulated mobile cranes

Non-slewing articulated mobile (NSAM) cranes are widely used in construction, manufacturing, and mining industries in Australia. However, the occurrence of several tipping accidents in Australia has raised concerns about their stability. This project aims to explore the operating factors contributing to the NSAM crane tipping accident, examine the inherent stability of the NSAM crane design, and suggest the potential development of a new monitoring system to reduce the likelihood of the accidents. It does this using geometrical modelling and theoretical static force analysis. A general static model for the stability study of NSAM cranes on slopes with various orientations is developed and an investigation into the tip-over and roll-over stabilities of the model under a number of static conditions is presented in this thesis. Based on the developed model, the articulation angle, the slope gradient, the orientation angle, and the height of the boom are the main operating factors contributing to the NSAM crane tipping accidents. The results of the examination of the inherent NSAM crane design suggests that having the articulation joints at the centre of the wheel base is a suitable design for NSAM cranes for the maneuverability and tip-over stability but not for the roll-over stability. After the explanation of the shortcomings of the current monitoring system for NSAM cranes, this project suggests the potential development of a new monitoring system based on the result of the developed model. Such a device would likely increase the safety of these machines.