A robust control method of a hybrid vibration absorber for vibration suppression in a wide frequency band considering large structural parameter variations

This article presents a robust control method of an active-passive hybrid vibration absorber for vibration suppression in a wide frequency band based on skyhook damping strategy. The technology of linear extended state observer is applied to automatically change pole locations of the system for stabilising the skyhook damping control, so that a high control gain can be used for effective control performance. Simulations on the vibration control of a single-degree-of-freedom primary structure via a hybrid vibration absorber are conducted to analyse the stability and performance of the present method. The results reveal that the present method is effective for vibration suppression and robust against marked parameter variations in both the primary structure and the absorber, when the controller is stabilised. Finally, this article demonstrates the effectiveness of the present approach for active control of multiple hybrid vibration absorbers to suppress multimode vibration. Simulation results show that the robustness against structural parameter variations is significantly improved compared to the previous approach, and all the vibration modes of the primary structure are suppressed effectively. In addition, by means of commercial dynamics software, simulations on vibration control of a cantilever panel via two hybrid absorbers are performed to further demonstrate the control effectiveness for a complex structure, where an analytical model is not available. Results indicate that the present method is effective and stable despite the large changes of the parameters.