Primary and Parametric Nonlinear Resonances of a Power Transmission Belt: Experimental and Theoretical Analysis

In this paper, the effect of pulley eccentricity on the vibration of a power transmission belt is experimentally investigated and a theoretical model is developed for validation and identification purposes. This eccentricity gives rise to dangerous operating conditions for the system, especially when it excites the frequency range of the belt resonances. As expected, the system shows a hardening non-linear behavior. Moreover, the fluctuation of the belt tension, due to the pulley eccentricity, gives rise to a parametric instability that can cause catastrophic failures of the structure. Laser displacement transducers are used to measure transversal vibrations of the belt. An approximate analytical solution of the travelling beam dynamics is developed in order to model the system and reproduce the experimental data. Comparisons between analytical solution and experimental data allow the identification of the unknown parameters of the analytical model. A validation of the identified model is performed by comparing analytical and experimental data in different operating conditions.