On the Statistical Correlation between the Heave, Pitch and Roll Motion of Road Transport Vehicles

A global economy is reliant on the movement of a great variety of goods on a large scale. Because the vast majority of goods are not sufficiently robust, protective packaging is needed to mitigate the adverse effects of shock and vibration that occur during distribution. In Australia and many other countries the predominant method for the transportation of goods is via a well-developed road network. To date, the vast majority of research into vibrations experienced during road distribution focuses only on the vertical motion of the transport vehicle as it has been shown to be the most severe. However, the pitching and rolling motions of the vehicle can contribute significant energy to the overall excitation of the vehicle and payload, and excite vibratory modes which are not stimulated by vertical vibration alone. This research focuses on investigating the heave, pitch and roll motions of light transport vehicles, and the relationships which exist between the vibratory modes. Two different approaches were used to investigate the relationships, a series of in-service field experiments and a complementary series of numerical experiments. The field experiments were designed to identify the influence of key parameters upon the relationships. The parameters investigated included; vehicle speed, road roughness, payload mass and payload inertial properties (CG location and MOI). Since the in-service experiments are, to a large extent, uncontrolled, numerical experiments were required to further investigate the vehicle parameters in greater detail. Numerical experiments allowed for controlled investigation of individual parameters which, in practice, are difficult or impossible to vary in isolation