Performance comparison of slow‐light coupled‐resonator optical gyroscopes

We investigate the connection between group velocity and rotation sensitivity in a number of resonant gyroscope designs. Two key comparisons are made. First, we compare two conventional sensors, namely a resonant fiber optic gyroscope (RFOG) and an interferometric fiber optic gyroscope (FOG). Second, we compare the RFOG to several recently proposed coupled‐resonator optical waveguide (CROW) gyroscopes. We show that the relationship between loss and maximum rotation sensitivity is the same for both conventional and CROW gyroscopes. Thus, coupling multiple resonators together cannot enhance rotation sensitivity. While CROW gyroscopes offer the potential for large group indices, this increase of group index does not provide a corresponding increase in the maximum sensitivity to rotation. For a given footprint and a given total loss, the highest sensitivity is shown to be achieved either in a conventional RFOG utilizing a single resonator, or a conventional FOG.     

基于编码标志点的数码相机三维测量与重构

介绍了利用数码相机作为图像传感器,在物体表面设置编码标志点,通过对编码标志点进行识别和检测,从而确定标志点的空间位置,实现了对物体表面某些特定点三维信息的无接触检测。介绍了其中的关键技术,如标志点的设计与检测、基础矩阵的求解、数码相机参数的标定以及内外参数的捆绑调整等,给出了检测实例并进行了精度验证。实验证明,该方法结构简单,成本低廉,数据采集快,移动方便,检测范围大,可满足三维物体特别是大面积物体空间检测的需求。     

对抛式冷原子陀螺仪中原子运动轨迹的控制

冷原子具有很小的速度,很窄的速度分布以及良好的相干特性,利用冷原子物质波干涉特性可实现原子干涉仪,具有萨格奈克效应的原子干涉仪即原子陀螺仪,可精密测量转动速率. 冷原子轨迹的精确控制对提高冷原子陀螺仪的测量精度有着重要的意义,文章报道了利用直接数字频率综合器,实现对双向对抛冷原子运动轨迹的精确控制. 关键词： 冷原子 原子陀螺仪 直接数字频率综合器     

微细铣刀位姿同轴全息重建方法

微细铣刀在主轴上存在装夹偏角时,会加剧刀刃磨损,降低刀具使用寿命.为了精确观测微细铣刀在机倾斜状态,提出了基于景深的微细铣刀三维位姿重建方法.利用激光同轴数字全息实验装置得到微细铣刀全息图,并通过菲涅尔再现算法获得再现像.在再现像中提取刀具边缘点作为关键点,采用小波变换局部方差算子求出关键点的聚焦程度,确定铣刀对应的轴...     

Frequency measurement study of resonant vibratory gyroscopes

In this paper, frequency measurement methods of resonant vibratory gyroscopes are studied. First, the working principle and dynamic output characteristics of the resonant vibratory gyroscope are introduced, which provide a theoretical analysis base to analyze the dynamic frequency output characteristic of the resonant vibratory gyroscope. Moreover, some relevant frequency measurement methods are introduced, a frequency measurement method based on dynamic output characteristics has been proposed for the purpose of investigating the modulated output signal of resonant vibratory gyroscopes. Finally, in order to verify the feasibility of the proposed frequency measurement method, resonator oscillator and dynamic frequency measurement experiments of the resonant vibratory gyroscopes are built. It is concluded from the resonator oscillator result that the designed and observed resonant frequency of the resonator have a good match, which shows the design of resonator oscillator is feasible. It is concluded from the dynamic frequency measurement result that correlation coefficient of output fitted curve is 99.95%, and the output characteristic of the gyroscope is linear frequency output, which shows the effectiveness of the proposed frequency measurement method.     

Gyroscopes used in inertial navigation

This article first defines inertial navigation and then considers a typical accelerometer. The basic law of gyroscopics is then derived, and the distinction between free, rate, and integrating gyroscopes is made. The design of the components of a gyro is discussed; ball and gas bearings for gyro wheels, gimbal suspensions (both floated and unfloated), and types of pickoff and torquer are mentioned, also a component which combines both in one unit. Future types of gyroscope are discussed, among them the electrostatic, cryogenic, laser and nuclear spin gyroscopes.     

卫星用光纤陀螺中抗辐射光纤的研究

介绍了光纤陀螺空间应用的优势及影响因素，提出了研究抗辐射光纤的防辐射加固方案。通过实验，证明了光纤的辐照效应，并提出了抗辐射光纤制备中的技术参考。     

集成光学陀螺及相关技术研究的现状与展望

陀螺技术作为惯性导航的重要组成部分已广泛应用于国民经济和军事工业的众多领域.文章综述了包括机械陀螺、光学陀螺和原子陀螺在内的陀螺技术的发展过程和基本特点,着重论述了集成光学陀螺及其相关技术研究的现状与发展趋势.通过对比各种类型陀螺的性能特点,结合导航技术的发展趋势,展望了各种陀螺在相应领域的发展前景.     

HYPER: A Satellite Mission in Fundamental Physics Based on High Precision Atom Interferometry

The article presents the HYPER project, a proposal for a satellite mission on precision matter-wave interferometry. For the mission several scientific objectives are under investigation, for which atom interferometers proved on ground to be a true complementary and competitive alternative for classical concepts: The application of atom interferometers as gyroscopes, the measurement of the gravitational acceleration (including tests of the universality of the free fall of atoms) and the precise determination of the fine-structure constant. The paper focuses on the use of cold-atom gyroscopes to map the Lense-Thirring effect close by the Earth and reports on results of recent feasibility studies of the European Space Agency. HYPER requires new concepts of compact, high-resolution matter-wave gyroscopes, which are better adapted to the use in satellite based experiments. The article will give a concise overview of the status and strategies in the field.     

光纤陀螺中的多功能集成光学芯片

介绍了多功能集成光学芯片在光纤陀螺中的应用。在光纤陀螺中采用了多功能集成光学芯片后 ,可以大大简化光纤陀螺系统的结构 ,缩小光纤陀螺的体积。光纤陀螺中的一些器件如相位调制器和光学开关、消光器甚至光波导谐振腔都可以集成在一个多功能集成光学芯片上。这样可以提高光纤陀螺的性能 ,增加其稳定性和可靠性 ,在某些特殊的设计中还可以对陀螺系统的误差进行补偿。     

Low cost, practical, all-digital open-loop fiber-optic gyroscope

A novel all-digital scheme for open-loop fiber-optic gyroscope (POG), where only two key points of output wave were digitized directly, has been proposed. A control equation, with which the modulation depth of PZT modulator is stable when setting the modulation depth as 4.35 and a calculation equation, with which the Sagnac phase can be worked out, are derived. A modulation depth control and an automatic correlation sampling and a gain control technology were induced. A photo-type FOG was made and tested. The good performance was achieved.     

基于光纤陀螺的舰载光电系统零值自跟踪稳定方式研究

从光纤陀螺的固有特性入手,结合舰载光电系统实现瞄准线稳定的需求,对基于光纤陀螺的瞄准线稳定控制系统进行了分析研究。针对船摇类扰动的作用机理,提出了基于速率光纤陀螺的舰载光电系统零值自跟踪的瞄准线稳定方法。     

高精度干涉式光纤陀螺热漂移分析

为了改进干涉式光纤陀螺的测量精度和温度性能,建立了该仪器输出偏置的解析模型。通过把光纤双折射这一从未被考察过的相位微扰与其它已知误差源进行线性叠加,该模型首次显式地把陀螺性能直接与光纤的力学、光学、热学和几何参数联系起来。利用该模型对常用于10-3 deg/h精度量级光纤陀螺的64层四极对称环圈进行计算,结果表明,保偏光纤所固有的高双折射及其温度涨落对陀螺输出偏置及其热漂移的影响分别在10-3 deg/h和10-2 deg/h量级,而过去研究较多的单模光纤中的舒普效应和热致光弹效应的影响分别在10-4 deg/h和10-3 deg/h量级。该模型表明保偏光纤所固有的高应力双折射是干涉式光纤陀螺的主要误差源,同时较为完备地描述了光纤陀螺中源于光纤性能的误差,也解释了该误差对光纤双折射的非线性依赖。     

半导体激光器实现波长转换的理论模型分析

作为自动交换光网络中的核心器件，全光波长转换器的研究是目前的热点。提出了基于半导体激光器实现波长转换的理论模型，采用小信号分析方法，利用速率方程求解了波长转换的频率调制响应特性。并初步研究了不同半导体激光器工作电流、码速、输入信号光功率、增益吸收系数条件对波长转换性能的影响。这对于优化基于半导体激光器的全光波长转换器有一定的参考价值。     

饱和吸收体实现波长转换的理论模型分析

作为自动交换光网络中的核心器件,全光波长转换器在网络中发挥着重要作用。基于半导体激光器速率方程,提出了新的基于饱和吸收体实现全光波长转换器的理论模型;并针对该理论模型,采用小信号分析方法讨论了波长转换的频率调制响应特性;数值求解了不同偏置电流、码速、输入信号光功率对波长转换性能的影响,对于实现和优化基于饱和吸收体的全光波长转换器有理论指导作用。     

Novel Indium Arsenide double gate and gate all around nanowire MOSFETs for diminishing the exchange correlation effect: A quantum study

In this paper we present novel double gate (DG) metal oxide semiconductor field effect transistor (MOSFET) and gate all around (GAA) nanowire metal oxide semiconductor field effect transistor (NWT) with a diminished exchange-correlation (Ex-Corr) effect. The key idea in this work is to use Indium Arsenide (InAs) semiconductor instead of Si. We have evaluated and compared different parameters of DG-MOSFET and GAA-NWTs such as threshold voltage, sub-threshold slope, drain induced barrier lowering and ON and OFF state currents from quantum view. Quantum mechanical transport approach based on non-equilibrium green’s function (NEGF) has been performed in the frame work of effective mass theory in consideration with Ex-Corr effect. This simulation method consists of three dimensional Poisson’s equation in which a Schrodinger equation is first solved in each slice of the device to find Eigen energies and Eigen functions. Then, a transport equation of electrons moving in the sub-bands is solved. This fully quantum method treats such effects as source-to-drain tunneling, ballistic transport, and quantum confinement on equal footing. The results show that only a few lowest Eigen sub-bands are occupied and the upper sub-bands can be safely neglected. Also, the interaction between electrons and Ex-Corr effect is diminished in the proposed structure.     

一致性绕射理论求解球面反射点的快速方法

射线寻迹是应用一致性几何绕射理论分析电大尺寸目标电磁辐射和散射特性的关键,它的精度和速度对场值求解结果影响很大。根据反射定律,推导得出了球面反射点的参量必须满足的一元四次方程,通过求解方程得到球面反射点。给出了应用此方法得到的部分球面反射点,并给出了球柱模型附近半波振子天线的远场方向图。一致性绕射理论结果与FEKO仿真结果吻合较好。     

数字化部队装备维修保障任务分配与调度框架研究

针对数字化部队装备维修保障需求,提出装备维修保障任务分配与调度问题,并分析问题特点与研究定位。基于霍尔三维结构,从要素维、逻辑维和知识维三个方面构建装备维修保障任务分配与调度的体系结构,并且在此基础上对装备维修保障任务分配与调度的组成要素、实施程序和技术方法进行系统分析。最后,对研究要点进行初步分析。     

一种用于计算三维视觉测量中线结构光平面的新型算法

介绍了一种基于线结构光的机器视觉测量系统的光平面计算方法.该方法采用图像减影来获取光条图像,利用Steger算法提取图像中的亚像素光条中心点,再用正交直线拟合法计算图像坐标系下的光条直线方程.通过靶标特征点的世界坐标和交比不变性,计算线结构光在靶标平面上的世界坐标点,并将这些坐标点用正交平面拟合法计算得到光平面方程.为了提高整体准确度,本文对算法进行了细节优化,给出了标定系统的设计方案和实验过程.实验结果表明,该方法具有较好的鲁棒性和较高的准确度.     

Sagnac gyroscope using a two-dimensional array of coupled optical microresonators

Micron-scale-integrated optical gyroscopes based on the Sagnac effect have a broad array of potential applications in navigation and inertial motion sensing due to the benefit of on-chip integration and potential sensitivities exceeding micro-electromechanical gyroscopes. Here, we analyze the Sagnac effect in a two-dimensional array of evanescently coupled optical microring resonators. We show that the sensitivity to inertial rotations greatly exceeds that of a single resonator with equal enclosed area. Moreover, a comparison between two-dimensional arrays and Sagnac gyroscopes consisting of one-dimensional distributed microresonators arrays of equal footprint shows that the sensitivity to rotations of the two-dimensional array exceeds that of the one-dimensional structures by as much as several orders of magnitude for smaller arrays.