航空学报 > 2001, Vol. 22 Issue (2): 102-108

变截面梁式压电智能板振动控制的小波模式

周又和, 王记增, 郑晓静   

  1. 兰州大学力学系,甘肃兰州730000
  • 收稿日期:1999-11-30 修回日期:2000-03-27 出版日期:2001-04-25 发布日期:2001-04-25

WAVELET-BASED MODEL OF PIEZOELECTRIC VIBRATION CONTROL FOR CANTILEVERED BEAM-PLATES WITH VARIABLE THICKNESS

ZHOU You he, WANG Jizeng, ZHENG Xiao jing   

  1. Department of Mechanics, Lanzhou University, Lanzhou 730000, China
  • Received:1999-11-30 Revised:2000-03-27 Online:2001-04-25 Published:2001-04-25

摘要:

基于 Daubechies小波理论的尺度函数变换 ,对于变截面悬臂板结构的弯曲建立了由压电片感应器的观测电量识别挠曲变形构形的显式关系式。此基础上 ,采用具有位移与速度信号负反馈控制律后 ,建立了抑制振动的压电动力控制程序。由于小波尺度函数逼近具有低带通性质 ,即具有自动滤除高频分量的能力 ,该控制程序将不会出现由观测溢出与控制溢出耦合而造成的控制失稳 (即在抑制低频 (阶 )扰动时系统激发出高频 (阶 )扰动的现象 )。数值仿真结果表明 :该控制方法所能控制的模态阶数与压电片数相同 ,而且其控制程序在抑制外界干扰方面是有效的。

关键词: 变厚度梁式板, 压电动力控制, 小波尺度函数变换, 挠曲变形识别, 控制程序, 数值仿真

Abstract:

Based on the scaling function transform of the Daubechies wavelet theory, an explicit expression of identification of deflection for cantilevered beam plates with variable thickness is obtained by the measurable electric charges and electricity from the piezoelectric sensors attached on the structures. After that, a control programme to the control system with piezoelectric sensors and actuators is established by means of a control law of feedback of negative signals of the identified deflection and its velocity to suppress vibrations of the structures. Due to the characteristic that the scaling function transform has a function of low pass filter which can auto filter out those signals of higher order dependent upon the resolution level of the wavelet theory, this control program on the basis of the wavelet theory can avoid the phenomenon of control instability that is caused by the coupling of spilling over of sensing and actuating, or in other words, that some higher order vibrations are excited when a lower order vibration is suppressed. The numerical simulations show that this control program can effectively suppress those disturbances spread from the lower order modals of the structure when the number of order of the disturbance is not greater than the number of piezoelectric actuators or sensors employed.

Key words: beam plates with variable thickness, dynamic control with piezoelectric sensors and actuators, scaling function transform of wavelet theory, identification of deflection, control program, numerical simulations

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