Virtual testing of articulated haulers

Abstract: Multi-body system dynamics is one of the most important theoretical achievementsin mechanics. With the development of the theory, corresponding commercialsoftware packages have been developed and are used for modellingand simulation of complicated large systems, such as air planes and vehicles.This kind of virtual prototypes can be used for studies and assessments ofreal systems even before the real systems are built. As a result, the high costprototype building and prototype testing can be saved, so as the time can bereduced. This is just the demand of modern industry. This theory can beapplied on the vehicle-virtual road interaction study which has been used inthis thesis.This thesis suggests a target velocity prole for a heavy vehicle which driveson tough road. Having uneven and hilly road, actual driving conditions arechanged as the driver runs the vehicle. Drivers can perceive the road conditionwith their visual organ and sense of balance and then they control theirvehicles more safely by re ecting various conditions of this target velocityprole. Without this process, the driving-stabilization on slope and twistingroads would fall considerably, and the problem could be directly connected tooverturning. This thesis, moreover, will show how to acquire the road data,extract the velocity prole, and verify the performance of the suggested velocityprole through virtual road test.In vehicle-virtual road interaction simulation, multi body system (MBS) dynamicswith software Adams has been employed to model an articulatedhauler. The simulation has been validated by velocity prole test data andcompared to the former velocity prole. This method can be used for estimatingthe eects of dynamic forces on the frame so that the load design canbe assessed in vehicle design process.This project is in collaboration with Volvo Construction Equipment AB,Braas, Sweden.