Analysis of the Dynamic Behavior of a Counterbalance Forklift Truck through Multibody Modelling and Simulation

This work deals with the analysis of the dynamic response of a counterbalance forklift truck prototype when performing standard verification maneuvers, defined by the manufacturer’s testing protocols. The research aims at developing numerical tools based on multibody models to predict accurately the dynamic loads acting on the forklift in the conditions of interest. In particular, this study focuses on a specific test condition, namely the passage on a steel plate obstacle at constant speed, which is one of the most severe maneuvers of the reference cycle in terms of dynamic loads. A model of the complete forklift is developed inside a commercial multibody environment. It takes into account the ground/tire interactions, by means of a simplified nonlinear contanct model, and the load handling assembly dynamics. An experimental campaign is designed and conducted to asses the vehicle behavior when running on the obstacle, by measuring the vibrations of the chassis and of the mast, as well as the forces generated by the mast tilting actuators. The measured data are exploited for model update and validation. The numerical results provided by the updated model show a satisfactory accuracy.