Off-highway truck setup influence on vehicle dynamics and frame durability

This work presents the development of a procedure based on the multibody dynamics and on the finite element method to analyze the dynamic response of an off-highway haul truck moving on rough unpaved roads. A multibody dynamics model of a haul truck is implemented to investigate the influence of seven different suspension-tyre setups on the cabin vibration and on the vehicle handling and ride comfort of a 64-ton vehicle. Typical truck maneuvers are simulated to evaluate the rolling angles, the seat vertical accelerations, and the steering behavior for the truck multibody model under loaded and unloaded conditions. Furthermore, a preliminary fatigue analysis of two welded joints of the truck frame is performed by using a special finite element procedure. Results rendered in this work show that softer suspension-tyre setups could enhance ride comfort by reducing root mean square of seat’s vertical acceleration by 10% and useful life of welded joints by up to 25% without affecting the truck handling, especially if mining roads are unable to impose lateral acceleration higher than 0.15 g.