【作者】 付江志；

【导师】 曹家年；

【作者基本信息】 哈尔滨工程大学 ， 光学工程， 2005， 硕士

【摘要】 本文设计了一种反射式光强调制型光纤传感器(RIM-FOS),用于测量低频振动加速度信号。由于只采用一根单模光纤用于发射和接收,使整体结构紧凑小巧且在一定条件和范围内使其数学模型相对简练,通过数字和线性化处理可不失真地实时输出低频振动加速度信号。此传感器具有信号失真小、对初始位移漂移不敏感的特点。 本论文首先介绍了光纤传感器和光纤加速度计国内外的发展状况,指出利用光纤传感是当今加速度计的研究热点。 本论文在第二部分从不同方面详细介绍了反射式光强调制型光纤加速度计的基础理论,并由此提出了一种新型的加速度计测量方案。文中详细分析了这种传感器的力学和光学工作原理,并且针对所选用的强度调制型光纤传感器的工作特点,从理论上证明了这种传感器对于发射光纤端面光强分布的不同模型(高斯分布、均匀分布或介于二者之间)都可以采用统一的公式来表示光强与位移的关系,其间只差一个比例系数。文中提出当二阶力学模型的参数选择适当时,力学模型中的质量块相对外壳的相对移与外壳的加速度近似成线性关系,因此采用光纤反射式位移传感原理测量二阶力学模型中的相对位移就可以达到测量二阶系统加速度的。 本文在其他部分还详细介绍了系统的具体设计与实现,包括对系统光源、光电探测器等器件的选择、系统硬件电路和软件模块的设计等。在硬件设计中通过单片机进行数据的采集、处理,同时采用12位的A/D和D/A转换器,确保有足够的测量精度。软件设计采用结构化程序设计方法,完成了数据的输入、存储、处理、输出等功能。更多还原

【Abstract】 A reflective intensity modulated fiber optic sensor is designed. It can be applied in the measurement of low frequency vibration acceleration.The configuration is compact and delicate for one single module fiber being used to send and receive.Its mathematic former is brief for certain conditions and ranges. By means of number and linearization processing, a real-time and undistorted low frequency vibration acceleration signal can be given out. The characteristic of the sensor is undistorted and unsensible to static drift of the initial distance.The global development of the optic fiber sensor and accelerometer is explained firstly, it is proved that optic fiber sensor has been a hot study focus in many scientists’ eyes.In second part of this paper,base theory of the fiber optic accelerometer is presented in details, according to the principle of reflective intensity modulations new experimental scheme is described. The paper analyzes in detail the mechanics and optics theory.In the light of the characteristic of the intensity modulation optical fiber sensor, the theoretical analysis shows that the relation between the light intensity and displacement can be indicated by the same expression, though models of the fiber-optic intensity distribution at launching fiber end are different, such as Gaussian distribution, uniform distribution and those midst the upper two.The reference-way is presented, when the factors of the second order mechanics model are proper, the relative displacement, body to shell, is linear to the acceleration of shell.So the acceleration of the second order system is measured by measuring the relative displacement with the optical reflection displacement theory.In other parts of this paper, the design of the system is described in detail, including the selection of system device, the design of systematic circuit and software. In the hardware design, a single chip computer is used to acquired andprocess the data.Using 12 bits’A/D and D/A converter renders certain the system’s measurement precision. The software’s design uses modular method to accomplish the system’s functions,including data input, storage, manage,output etc.更多还原