Modelling and vibration suppression of a transmission system with a curved beam-based nonlinear energy sink

The electromagnetic excitation of the motor affects the vibration characteristics of the transmission system it drives. This study employs a curved beam-based nonlinear energy sink (CNES) as a suppression measure to reduce torsional vibrations in a multi-degree-of-freedom transmission system subjected to both electromagnetic and external excitations. An approximate expression for the electromagnetic excitation is established, and its influence on the inherent characteristics of the transmission system is analyzed. Next, the structure and principles of the CNES are introduced, followed by the development of a dynamic model for the transmission system that incorporates the proposed CNES. Building on these foundations, the energy transfer of the CNES under transient excitations is analyzed using an analytical method. Further numerical analysis is conducted to examine the displacement attenuation and energy dissipation of the transmission system with CNES installed. Furthermore, this study explores the influence of the electromagnetic excitation on the response characteristics of the system and numerically analyzes the vibration suppression performance of the CNES on steady-state responses. Finally, an experimental platform for the transmission system is established, and the suppression performance of the CNES is validated through experiments. The results indicate consistency between the experiments and simulations regarding the performance of the CNES. This study offers valuable insights into the suppression of multi-modal vibrations in transmission systems subjected to multi-source excitations.