Yh. Zhou et al., Vibration control of variable thickness plates with piezoelectric sensors and actuators based on wavelet theory, J SOUND VIB, 237(3), 2000, pp. 395-410
An approach of dynamic control for suppressing external disturbance to vari
able thickness beam plates with sensors and actuators of piezoelectric laye
rs on/in the structures is proposed in this paper using the scaling functio
n transform of the Daubechies wavelet theory for approximation of functions
. By means of the generalized Gaussian integral to the scaling function tra
nsform, an expression of identification of deflection configuration of the
structures is explicitly formulated by the electric charge/current signals
measured from the piezoelectric sensors. After a control law of negative fe
edback of the identified deflection and velocity signals is chosen, the wav
elet Galerkin method or wavelet weighted residual method is used to determi
ne control voltage applied on the piezoelectric actuators. Due to that the
scaling function transform is like a low-pass filter which can automaticall
y filter out high order signals of vibration or disturbance from the measur
ement and the controller employed here, this control approach does not lead
to the undesired phenomenon of control instability that is often generated
in a control system and caused by the spilling over of high order signals
from interaction between the measurement and the controller if no special t
echniques is used in the control system. Finally, a numerical simulation is
carried out to show the efficiency of the proposed approach. (C) 2000 Acad
emic Press.