基于图论及应变花的光纤自诊断网络可靠性研究

Studies on the Reliability of the Optic Fiber Self-diagnosing Network Based on the Graph Theory and Strain Rosette

以某飞机机翼盒段上布置的对结构应变分布进行监测的光纤Bragg光栅自诊断传感网络为例,对提高光纤自诊断网络系统的可靠性方法进行了研究.在传感器排布方式上,对监测点采用光纤应变花的形式;在网络连接上,采用图论中邻接矩阵的方法通过使光开关动作为失效传感器寻找新的解调路径,实现信号的重新解调.结果表明,采用图论中对邻接矩阵的运算同传感器容错技术相结合,可使光纤网络系统在一根或几根传感器信号同时失效时,在不破坏结构的前提下,仍能利用受损区域内存活的光纤传感器,完成自诊断网络的自修复,达到提高网络可靠性的要求.

For improving the reliability of the optic fiber self-diagnosing system, a Fiber Bragg Grating sensor net- work which is applied to monitor the strain distribution of a certain aircraft wing box is researched. Considering the sen- sor arrangement, the optic fiber strain rosette is adopted in the monitoring point. Considering the network connecting type, the optical switch and the adjacent matrix of the graph theory is adopted to connect the demodulation equipment for the disabled sensor signal in a different path once more, thus the disabled sensor signal can be demodulated again in the optic fiber sensor network. The research results indicate that if one or more sensor signals in the optic fiber net- work system disabled simultaneously, depending on the healthy Fiber Bragg Grating sensor in the damaged regions, the adjacent matrix of the graph theory combining with the fault-tolerant technique can be adopted to achieve the self-recov- ery of the self-diagnosing sensor network without damaging the structure.