Abstract: Design and calculation of multi-axis vehicle obstacle surmounting performance has been a difficult problem in vehicle product development. Therefore, this paper takes an 8× 8 heavy truck as the prototype vehicle and considers the tire radial elasticity on the basis of preliminary model with the assumption of rigid tires. The step crossing mathematical model of each axis is established and the numerical calculation is carried out. The calculated results are agreeing with the experimental values, indicating the accuracy of the model. Finally, based on the established model, the influence of the adhesion coefficient, the vehicle center of mass position, the height of the center of mass on each axis obstacle surmounting performance is analyzed.

Key words: heavy truck, balanced suspension, tire elasticity, obstacle surmounting performance, experiment