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.

Experiments on vibration transmission control in a shaft-hull system excited by propeller forces via an activemulti-strut assembly

“…Merz et al 21 studied the combination of RC and distributed active vibration absorbers in controlling the vibration of the shafting system and the acoustic radiation of the hull. Hu et al 22 used an electromagnetic actuator to directly control the longitudinal vibration without changing the inherent longitudinal and lateral characteristics of the shaft, and the experimental results show that vibration can be attenuated by 10-20 dB within 10-200 Hz.…”

Investigation on vibration transmission control of a shafting system with active orthogonal support

“…Daley et al (2004) developed a new hybrid passive/active mounting system that is of the potential to eradicate undesirable signatures of the hull structure. Hu et al (2012) proposed an active control method to attenuate the longitudinal vibration of shafting systems, and the experimental results indicate that the control method can effectively suppress periodic disturbances. Qin et al (2019) proposed a new approach that uses electromagnetic bearings to suppress lateral vibration transmission and reduce acoustic radiation.…”

Elimination of friction-induced vibration of a propulsion shafting system by auxiliary electromagnetic suspension

“…Moreover, many active control methods have been adopted to control vibration of the propulsion shafting systems. For example, Hu et al (2012) proposed a model-free control method established on the least-mean-squares-based adaptive feedback principle to actively suppress tonal structural vibration. Xie et al (2019) presented an active control strategy to reduce vibration transmission in a shaft-hull coupled system by using a 6-DOF active stern support and the local velocity feedback control.…”