Tonal vibration suppression with a model-free control method

Abstract

A novel model-free control method for actively suppressing tonal structural vibration is investigated through numerical simulation and experiment. The model-free control method is established on the least-mean-squares-based adaptive feedback control principle, and an instrumental mechanism for adjusting the controller parameters is proposed to guarantee convergence of the algorithm. In the numerical verification of the model-free control method, a shaft–plate system is used to derive a lightly damped dynamic model, which is obtained by frequency response function synthesis, while in the experiment a shaft–cylinder system with time-varying dynamics is applied to evaluate the control system with respect to its potential in vibration control. In the control system, an electromagnetic actuator mounted on the shaft is enforced with the model-free control method to cancel vibration induced by the disturbance forces. Simulation results have demonstrated that the model-free control method is able to guarantee stability in the presence of changes in the disturbances and plant dynamics and that it is effective in attenuating vibration of the system. Experimental results have also demonstrated that the control system can tranquilize vibration of the shaft and suppress tonal vibrations in the shell effectively, but variation in the control channel should be sufficiently slow that the algorithm can complete its adaptation in time.