Theoretic Research on Fiber Accelerometer of MEMS
|Course||Condensed Matter Physics|
|Keywords||MEMS Fiber Optic Sensors Acceleration sensor Structural design Michelson interferometer|
Micro- acceleration sensor has the characteristics of high reliability, high sensitivity , has received extensive attention in the automotive industry, aerospace , bio- and medical fields . At present, most of the micro - acceleration sensor measuring principle capacitive, piezoresistive , thermocouple more mature structure for optical micro-accelerometer , and the combination of fiber and mature optical fiber sensing technology acceleration sensor little research . Paper application of MEMS technology and optical fiber interferometer principle of combining a fiber optic micro - acceleration sensor , the sensing mechanism of the system , the optical system , the signal processing system research . To a certain extent hard to narrow down the problem to solve ordinary fiber optics made ??size , while at the same time to make up for the integrated optical waveguide device fabrication high degree of difficulty and loss greater shortcomings and deficiencies . This paper first introduces the research status and development trend at home and abroad on the micro- acceleration sensor , discussed the basic principles of optical fiber sensing technology , analysis of several typical phase modulation interferometer interference principle , for later acceleration measurement theory foundation. Secondly, the Michelson interferometer -type fiber-optic accelerometer structure and working principle conducted in-depth research . Departure from the sensing principle , discussed and derived light propagation time drive in the optical path difference change . The working process of the fiber optic accelerometer : The sensitive components feelings outside of the acceleration signal , and to transform it into a Michelson interferometer fringes mobile number of mobile interference fringes which represents the measured acceleration values ??. Again , the use the material mechanics principles to establish the displacement of the mass equation of motion , and they are linked with the measurement of interference fringes Live , in order to achieve the conversion of the motion amount to the amount of optical analysis of the various design parameters of the sensing system of the sensor range , resolution and measurement accuracy , performance , given the theoretical value of the design parameters of the selection principles as well as technical indicators . Finally, due to the accelerometer output signal is usually subject to random noise interference , so the acceleration sensor noise sources , and on this basis , some of the possible solutions .