Analysis of the Dynamic Response of an Industrial Tow Tractor through Multibody Simulations

This work investigates the dynamic response of a stand-on industrial tow tractor. The final goal is developing a multibody-based simulation tool capable of estimating reliably the vibration levels transmitted by the vehicle to its operator. Experimental tests are conducted on the tow tractor to measure the vertical accelerations experienced at the front and rear axles and on its floating platform when running at constant velocity over an obstacle, which is one of the most critical maneuvers in the manufacturer’s testing protocols. A multibody model of the complete vehicle is developed through commercial software. A simplified model of the operator is also included, to reproduce the response of the human body to the transient perturbation induced by the obstacle, which significantly affects the platform response. Modal updating is performed by adjusting the parameters of the contact functions adopted for the ground/wheels and platform/feet interactions. The updated model satisfactorily matches the experimental signals in terms of peak amplitudes and trend of the accelerations.