Optimizing And Testing Of Fiber-Optic White Light Interferometer Based On The FPGA Technique

In order to realize the synchronous real-time sampling of multiple channels bridge structural health monitoring and the miniaturization of the instruments,an optimization of the optical system design was required.The new design was based on the original instrument configuration,especially in the hardware components.The Field-Programmable Gate Array(FPGA)was employed.The optimization design was divided into two parts: multi-channel high-speed Ethernet acquisition system and brushless Direct current(DC)motor driving system.This thesis firstly described the use scenario,monitoring principle,structural parameters,monitoring and data processing of the original instrument.At the same time,the system and hardware problems of the original instrument in further experimental research were pointed out.It was difficult to achieve multi-channel synchronous sampling and there was still room for optimization in structure.Secondly,introduced Xilinx FPGA and the corresponding software used in the research and design.It included AX545 development board with Spartan-6 series of FPGA as a main control chip,ISE14.7 version hardware & programming software and Altium Designer 17.0 circuit board drawing software.Thirdly,the causes of the system problems were analyzed,and the optimization scheme was given: using multi-channel parallel data sampling and transmission based on Ethernet communication.The real-time synchronous acquisition of multiple monitoring signals was achieved.It also introduced the protocol and function of Ethernet and the corresponding module function of the system.Fourthly,the difference between stepping motor driving and brushless DC motor driving was analyzed in detail.The schematic diagram of brushless DC motor driving was given.The driving board was designed.At the same time,the functional composition of motor driving,related structural parameters,and the adaption design of acquisition system and motor drive system were described.Finally,the preliminary verification of the acquisition system was carried out by using signal generator and Wireshark software,and the verification was further completed in the relevant monitoring and testing.At the same time,using FAULHABER brushless DC motor to test the driving board,and verify whether the driving system of brushless DC motor was feasible.The test results showed that,on the basis of retaining the acquisition function of the original instrument,the new data acquisition system could achieve multi-channel data acquisition and transmission function.And there is no packet loss and error code in the transmission process.The motor could be rotated smoothly at high speed and basically achieve the function of the motor driving system.It showed that the optimum design of the instrument achieved the expected purpose,and the design system had high application value,which laid a foundation for further research and design.