Online health monitoring system and method for composite material

The invention discloses an online health monitoring system and method for a composite material. The system comprises an optical fiber grating demodulator, an optical fiber coupler, a processor and a double-lead array optical fiber grating pair sensor. A light source emits light signals, and the light signals are divided into two ways through optical fibers, and connected to the two ends of the double-lead array optical fiber grating pair sensor through one optical fiber coupler. All optical fiber gratings are embedded into the composite material. After the light signals and the optical fiber gratings are mutually affected, reflected light enters the optical fiber grating demodulator through the optical fiber coupler. The optical fiber grating demodulator is connected with the processor. The processor calls a damage database of the composite material, analyzes the damage type, degree and distribution of the fiber composite material to set up a three-dimensional model, outputs the damage distribution of the composite material, calculates residual intensity of the composite material by means of finite element analysis, and evaluates the health condition of the composite material. The system monitors the damage state of the composite material and gives out early-warning in real time.