A 9-dof Displacement Analysis of a Large Truck Plying a Rough Road

Abstract

We present a 9-degree of freedom analysis of a 2D truck with the assumption that the coefficient of damping can be modelled as proportion to the stiffness matrix. There are nine modes of vibrations observed. The modes of vibration show that the articulated vehicle un-sprung masses move in different phases relative to one another in the modes. A driving comfort measured by the impact response in the driver cabin for the selected stiffness matrix is only 1.32% relative to acceleration of gravity. The sinusoidal road profile gives an oscillating response in the trailer compartment which settles to a sinusoidal amplitude of 0.5o from an initial 1.5o amplitude, while the driver cabin oscillation is only 0.02o . This is a comfortable ride without consideration for seat ergonomics and the physiological effect of low frequency vibration and long time driving.