Design Of A Strain Measurement System Based On A Fiber Optical Interferer Sensor

In this paper ,we introduce a design of a strain measurement system based on the 3×3 directional coupler which is mainly used in the laboratory. The theory of the system and how to design the soft and hard system are also discussed in the paper. In the thesis the discussion as following:At first, we discussed the research on the fiber optic sensor in and out of our country. Describing the condition of the interference,the visibility of the grain and the influence factors had also been carried out.Secondly,we discussed the theory of the Michelson fiber optical sensor.Giving the way to realize the light system including the circuit design of the laser and light detector, showing how to organize the whole measurement system,the way of polished the end face of optic fiber and how to improve the quality of signal.Thirdly,we discussed the compose of the circuit of the whole system.Based on the need of the measure system we design the driving circuit of the light source ,the circuit of the light converting to electric .then we discussed how to deal with the signal such as the signals magnify how to acquire the signal and determine the direction of the strain. Besides these, we also discussed how to design the circuit based on the core of the AT89S52, and how to design the software of the system based on this circuit.In order to realize the system, we choose the proper microcontroller and CPLD and program the code. Also we introduced the MAX+PLUS II,the digital logical circuit circumstance,and how the design the digital logical circuit on this circumstance.we also wrote a program to show the signal, the number of strain and the strain direction and so on.At last,the relate examination and the demarcate of the measure system had been carried out.The relate datum also had been analysed.