Theoretic Research On Fiber Sensor Of 3D Acceleration

Acceleration sensor with high reliability and high fidelity is needed more in the field of automotive industry, spaceflight, biology, medicine and etc.Current research and engineering occasions put forward higher demands of three-dimensional measurement of acceleration, thus this paper presents a new fiber-optic acceleration sensor design, and does systemic research about the transducer, demonstrating the structural design, the measuring principle as well as its parameters and performance indicators of the three-dimensional acceleration. The main work of this paper is as follows:First of all, this paper introduces researches and development trends about the multi-dimensional acceleration sensor at home and abroad. Then the basic principles of the optical fiber sensing technology are discussed, and sensing mechanism of several typical phase modulation-based interferometers is analyzed, which provides a theoretical foundation for the derived acceleration measurement principle in the later part.Secondly, according to the function, systemic light source, sensitive element, conversion and measurement circuits, as well as the calculation of three-dimensional acceleration and output modules are divided, and each structure is designed in accordance with the division.For the core of this article, that is, the design of the sensitive element, it combines the elasticity flat diaphragm, holographic grating and pyramid prism, using two-dimensional laser angle measurement and Michelson interference principle, which can extract and at the same time measure the three-dimensional acceleration signals at a higher accuracy.Thirdly, it builds the space motion equation of the diaphragm displacement and beam structure torsion by using the relevant principles of mechanics of materials, and their interference fringes and measurement of contact information, and thereby realizes the conversion from movement parameter to optical parameter.Finally, it analyses how each design parameter of sensor system influences the capability of sensor range, resolution and measurement accuracy and etc., and also gives principles of selecting design parameters and the theoretical value of technical indicators.