Truck Suspension Models

Abstract

Laboratory experiments on an International ACCO 1810A truck rear suspension unit are used to assess the validity of mathematical models for the tire and spring. Best results are achieved with tire and spring models that are nonlinear, with separate, fixed loading and unloading curves joined by loading and unloading transitions. The use of a linear tire model with an unloading curve set at 0.9 times the loading curve causes only a small degeneration in accuracy. Alternatively, a linear tire model with a viscous damping coefficient of 0.015 kN/mm/s gives reasonable results. The accuracies achieved with linear models for the suspension spring appear to be unsatisfactory. Details of the transition curves for both tire and spring are unimportant provided that the base length (along the deformation axis) is small.