Development And Application Of A Kind Of OFBG Accelerometer With Temperature Self-compensation Function

Along with the maturity and development of Optical Fiber Bragg Grating(OFBG) sensing technology, OFBG sensors with different functions have beendeveloped and applied in large-scale engineering structure health monitoring andconstruction monitoring. OFBG sensors can provide many measurement functionsand satisfy different measurement requirements. OFBG sensors have the advantageof high durability and stability. Aiming at the strain and temperature sensingproperties of OFBG, considering the environment temperature change which canlead to a big influence on the test results especially for the long-term test, anaccelerometer with low frequency and a characteristic of temperatureself-compensation function is introduced in this dissertation.Firstly，design and analysis works were carried on. It is a cantilever structuremodel with equal strength beam, fix a mass block at the end of the beam, paste twoOFBG on the upper and lower surface axis of the beam at the corresponding places,package at last. Because of the two OFBG are near to each other, the wavelengthvariations in both OFBG caused by change of the temperature is equal. According tothe temperature self-compensation principle and acceleration measurement principleshown in this dissertation, we can eliminate the influence of temperature changewithout measuring it and get the real wavelength variation only caused by stress, atlast achieve the temperature self-compensation function of real accelerationmeasurement by simply calculating the test results.Secondly, considering the measuring range and frequency requirement, we candesign the size of different construct of the accelerometer respectively. Identify theprocessing craft and manufacture the accelerometor. We will do research on thecalibration experiment, data comparison, site experiment, data processing,temperature compensation effective analysis and the improvement of processingcraft etc.Lastly, to prove the correctness of the principle of acceleration theory, thepracticality of the product, the validity and the importance of the temperaturecompensation function by data processing during long-term test. The experimentalresults show that, this type of accelerometer has high sensitivity and stability and itsperformance parameters can also be changed according to the practicalrequirements. The research results show that because of the obvious temperaturecompensation effectiveness, this type of accelerometer is suitable for engineeringstructure acceleration measurement during a long term without considering thetemperature change of the environment.