利用混沌振子系统识别超声导波信号的仿真研究

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振动与冲击 ›› 2012, Vol. 31 ›› Issue (19) : 15-20.

论文

利用混沌振子系统识别超声导波信号的仿真研究

张伟伟1 马宏伟2

作者信息 +

Simulations on ultrasonic guided wave identification using chaotic oscillator

ZHANG Weiwei1 MA Hongwei2

Author information +

文章历史 +

摘要

本文提出了一种基于改进型杜芬混沌振子系统的强噪声下超声导波的识别和定位方法。首先，采用(-x3+x5)作为杜芬方程的非线性恢复力项，提高了系统的敏感性；其次，利用Melnikov方法、并结合待检测信号频率、噪声水平设置了杜芬系统参数；再次，利用驱动力幅值变化使得杜芬系统产生间歇式混沌，并将系统由大周期态向混沌吸引子过度的临界态作为检测系统。为了说明杜芬系统对噪声信号的免疫力，分析了随机噪声对系统扰动的统计特性。最后，利用导波信号对系统相轨图的显著变化识别导波信号，并提出了二分法用于识别导波发生时刻，并对输入信号的长度影响进行了讨论。仿真算例表明，利用杜芬系统相轨图对噪声和导波信号截然不同的响应特点，可以有效地检测弱导波信号，该方法对于延长导波的检测范围、以及提高微缺陷的检测灵敏度具有重要意义。

Abstract

A novel inspection method of the ultrasonic guided wave was proposed in this paper, which was based on the improved Duffing chaos oscillator with substitution of (-x3+x5) for (-x+x3) for the non-linear item. Firstly, the effect of the frequency and damping ratio on the chaotic systems were studied using Melnikov’s method. Based on this, the frequency of the force and the damping ratio could be determined considering the frequency of the signal and the noise lever, respectively. The chaos system could transfer the phase from the quasi-periodic motion to chaos motion with double attractors by changing the amplitude of the fore. And then, the statistical properties of the effect of the noise on the system were discussed in detail. It is obviously different on the non-balance phase transition of the system, which induces to chaos motion with double attractors when inputting the guided wave signal but only induces to a disturbance when inputting the pure noise. Furthermore, a dichotomy was suggested to locate the time of the guided wave. And the effect of the length of guided wave on the phase map was studied in detail. The simulations show the sensitivity of the system to the guided wave and the strong immunity to the noise. The presented method could be used to inspect weak guided wave. It is important to extend the detection range and increase the sensitivity of detecting micro-defects.

导出引用

张伟伟马宏伟. 利用混沌振子系统识别超声导波信号的仿真研究[J]. 振动与冲击, 2012, 31(19): 15-20

ZHANG Weiwei MA Hongwei. Simulations on ultrasonic guided wave identification using chaotic oscillator[J]. Journal of Vibration and Shock, 2012, 31(19): 15-20