NEW MODEL OF THEODOLITE INDUSTRIAL MEASURING SYSTEM

Comparing with the coordinates measuring machine (CMM),the theodolite industrial measuring system (TIMS) can be easily moved and it can measure large sized industrial targets contactlessly.But up to now the precision of the TIMS has been considered so low that the TIMS isnt applied to some precise measurements.The error in self locating TIMS is a main factor which affects the precision of the TIMS.A new model of the TIMS is given out in this paper,and it can eliminate the error in self locating the TIMS.The new model is not only investigated and analyzed theoretically but also verified by the real measured data.

Theoretical Study of Multi-Theodolite Measurement System

In the field of aerospace, theodolite system is often used in the inspection of large object. A new measurement system that consists of four theodolites is presented in this paper, with which the "blind" problem raised in Original dual-theodolite system can be overcome. The principle of multi-theodolite system, together with the mathematicalmodel (both of calibration and of measurement) is given. And also the calibration process is discussed.

THE THEORY AND APPLICATION OF THE STRUCTURE LIGHT ENGINEERING SURVEYING BASED ON A LASER THEODOLITE WITH THREE FREEDOMS OF ROTATION

The concepts of “confining structure” and structure light are illuminated in this paper.A laser theodolite with three freedoms of rotation,which is aimed at “confining structure”,is developed.Various scanning modes and their mathematical models based on laser theodolite with three freedoms of rotation are discussed.According to the features of a huge object,,the structure light engineering surveying based on laser theodolite with three freedoms of rotation is determined as the main method in an actual application.The observation of four sound concrete posts and forced centering plates.Subsequently,it is transformed into the huge object coordinate system.The scanning mode with plumb plane is selected as the main mode in the whole work.And other assistant methods,such as close range photogrammetry and the method of using reflection sheet,are applied to the work of “scanning dead angle”.At last,a surveying accuracy estimation of this method is done and a surveying accuracy test is finished.It can be concluded that the structure light engineering surveying based on laser theodolite with three freedoms of rotation is considered to be an effective and applied method,and has many superiority to some other surveying methods in the work of surveying “confining structure”.

Improvement Detecting Method of Optical Axes Parallelism of Shipboard Photoelectrical Theodolite Based on Image Processing

An improvement detecting method was proposed according to the disadvantages of testing method of optical axes parallelism of shipboard photoelectrical theodolite (short for theodolite) based on image processing. Pointolite replaced 0.2'' collimator to reduce the errors of crosshair images processing and improve the quality of image. What’s more, the high quality images could help to optimize the image processing method and the testing accuracy. The errors between the trial results interpreted by software and the results tested in dock were less than 10'', which indicated the improve method had some actual application values.

Bundle adjustment for data processing of theodolite industrial surveying system

The photogrammetric bundle adjustment was used in data processing of electronic theodolite industrial surveying system by converting angular observations into virtual photo coordinates. The developed algorithm has ability of precision estimation and data snooping, do not need initial values of exterior orientation elements and object point coordinates. The form of control condition for the system is quite flexible. Neither centering nor leveling is the theodolite needed and the lay out of theodolite position is flexible when the system is used for precise survey. Experiments carried out in test field verify the validity of the data processing method. [

Hermeneutical Theodolite of Requirements: Evaluating and Revealing the Quality Grades of Software Requirements and of Domain of Application

Throughout the development of software, during Requirements Engineering activities, software requirements dynamically and constantly evolve and mature from an “identified” stage to an “approved” stage. This evolution takes place individually for each requirement, in a very particular way, because it depends on the level of understanding that the requirements engineer reaches in relation to it. How, then, to monitor the evolution of each software requirement? How to know the quality of each software requirement? How to measure the level of understanding and difficulty that the requirements engineer has in relation to each software requirement? This paper aims to present a proposal to answer these questions through the use of an instrument developed specifically to assess and reveal the quality grades of each software requirement and also to assess and reveal that the levels of understanding and of difficulty of the requirements engineer is in relation to each software requirement. This instrument was called the Hermeneutical Theodolite of Requirements, which also can be applied to evaluate that the levels of understanding and of difficulty of the requirements engineer is in relation to the domain of application, essential input artifact and primordial to the specification of the requirements of software.

Optical-Electrical Characteristics and Carrier Dynamics of Semi-Insulation GaAs by Terahertz Spectroscopic Technique

OaAs has been widely used to fabricate a variety of optoelectronic devices by virtue of its superior performance, and it is very important to accurately measure its electrical and optical properties. In this study, a semi- insulation （SI） GaAs wafer is investigated by the terahertz （THz） non-destructive testing technology. Using an air biased coherent generation and detection THz time domain spectroscopy system, the THz time domain waveform and spectrum of SI-GaAs are obtained by the time domain spectroscopy module, and its optical- electrical characteristics including complex refractive index, permittivity and dielectric loss angle are calculated. Its carrier lifetime is measured by the optical-pump THz-probe module, and the THz pulse induced intervalley scattering in photo-excited SI-GaAs is discussed.

子午工程二期自动磁通门经纬仪

地磁台站观测有相对记录和绝对观测2种,相对记录数据需经基线值改正后方可得到地磁场要素的实际值.磁通门经纬仪是获取基线值的基本设备之一,在地磁观测中发挥着重要作用.目前台站采用的磁通门经纬仪需人工操作,人为因素会对观测数据质量产生影响,因在偏远地区和环境恶劣地区无法实现地磁绝对观测,造成地磁绝对观测的空间覆盖空白.子午工程二期将在我国内地地区首次开展自动化磁偏角和磁倾角地磁绝对观测,必将推动地磁绝对观测技术创新与发展.自动磁通门经纬仪是我国自主研发的磁偏角和磁倾角自动化观测设备,采用无磁材料和压电电机,通过优化设计与改进加工工艺,以及引入多参量误差补偿算法,有效克服和消除了系统误差,提高了测量精度.该设备在河北涉县台、吉林合隆台、陕西乾陵台和北京白家疃台等台站开展了长时间的实际观测,并与台站的人工磁通门经纬仪观测结果进行了对比.结果表明,自动磁通门经纬仪的主要性能指标达到了人工磁通门经纬仪水平.该设备也通过了中国地震局前兆设备入网测试,功能和性能指标符合地磁台站地磁绝对观测要求.

高精度小型经纬仪转轴锁紧机构结构设计

随着光测设备对机动化、小型化的需求增多,受系统空间限制,原大型经纬仪的转轴锁紧机构复杂,占用空间大,加工难度大,并不适用小型经纬仪转轴锁紧。本文根据项目特点设计了小型经纬仪转轴锁紧结构,具有稳定性高、结构简单、加工难度小、占用空间小等特点,可以实现经纬仪在任意角度的转轴锁紧,实现凝视功能。其中对锁紧机构的组成与工作原理进行了详细的介绍与阐述,经过计算选择核心零件的材料,实践结果表明了该结构的合理性。

基于MLE的靶场光电经纬仪高精度定位方法研究

为解决靶场光电经纬仪现用交会定位解算模型作用范围小、与目标实际位置偏差大等问题,提高目标航迹解算精度和模型的适应范围,根据目标跟踪距离和测角误差分量关系,建立了经纬仪空间测量误差模型,优化了异面交会定位加权系数。基于最大似然估计(Maximum Likelihood Estimate,MLE)理论,提出了一种新的更高精度的定位方法,并推导了精度估算公式。详细分析了交会角度、跟踪距离和测角精度对定位误差的影响。试验证明,该方法较现用定位方法适用测量区域增加一倍以上,定位精度提高20%,更适合多测站、不等精度、远距离跟踪等工程场景,具有推广价值。

光电经纬仪自抗扰控制方法

为提升光电经纬仪在跟踪时的响应速度和抗干扰能力,提出一种基于观测器的自抗扰控制(active disturbance rejection control,ADRC)方法。对所有已知或未知的影响直流电机工作的干扰输入进行在线估计,并通过适当的反馈控制法来补偿这些干扰;通过选取合适的观测器和控制器带宽参数,来实现良好的抗扰控制效果。仿真结果表明:基于观测器的自抗扰控制方法能有效地提高直流电机对外部干扰和内部未知参数变化的鲁棒性,具有工程应用前景。

楔块式自动调平机构设计与控制策略研究

针对目前使用的经纬仪调平机构人为手动操作方法存在的调平耗时长、结构易损和难调平问题,设计了一种具备稳定自锁特性的大行程、高分辨率楔块式自动调平机构,提出了楔块式机电调平组件联动的并行调平控制策略。实验结果表明,所设计楔块式自动调平机构可实现调平行程±0.25°范围内的经纬仪调平,且调平角分辨率<0.01″。同时,基于并行调平控制策略,将绕X轴和Y轴的垂直轴轴线倾斜量从334″和-248″调整至2″误差范围内的调平耗时仅为17 s,相比于串行调平控制策略,调平时间显著缩短,调平效率明显提升。

并联结构轴系回转误差建模及装配优化

为提高光电经纬仪等二维转台的轴系运动精度,本文基于雅可比旋量理论建立了一种可考虑零件结构误差及其耦合放大效应的数学模型。针对“一端固定、一端游动”的轴系结构,提出了局部并联结构的分析方法。通过数值仿真分析,获得了各零件结构误差对轴系运动精度的影响以及最优的轴系装配方案。光学口径为650 mm的光电经纬仪的装调结果表明:装配优化后的轴系运动精度较优化前提高了32.1%。所构造的轴系运动精度模型及优化方法为指导光电经纬仪等二维转台的轴系装调以及公差设计提供了一定的理论根据。

基于动态门限与自适应插值的外引导平滑算法

为了实现靶场光电经纬仪外引导数据的实时平滑,确保外引导数据驱动下光电经纬仪稳定获取图像,提出基于动态门限的野值处理算法和基于自适应插值的处理算法。对于外引导数据中的野值,提出一种利用影响函数动态计算样本方差的方式,构建动态判别门限实时完成野值的处理;对于外引导数据的插值处理,判断插值计算的连贯性,并将外引导的“卡顿”数据进行分类,采取不同的策略实时自适应插值。实验结果表明:基于动态门限的五点外推野值剔除方法,野值检测率平均在80%以上,同时虚警率较低;插值处理算法能同时应对卡顿与非卡顿的外引导数据,处理结果平滑连贯。算法已成功应用于海军某观测站的光电经纬仪,满足了靶场弹道测量系统的需要。

船载单轴旋转惯导系统转轴倾角动态标定方法

大型航天测量船对船载惯导系统的姿态精度要求很高,其中转轴倾角是影响单轴旋转惯导系统姿态精度的主要因素之一。目前,转轴倾角标定多在坞内静态条件下进行,船舶系泊或动态航行状态下的转轴倾角标定是需要解决的现实问题。为此,提出了一种基于经纬仪测星的转轴倾角动态标定方法,推导了测恒星解算转轴倾角的数学模型,分析了转轴倾角误差的可观性,最后给出转轴倾角的最小二乘解。仿真结果表明,所提方法在仅观测3颗恒星条件下能准确估计出转轴倾角。坞内静态标定和海上动态标定实验结果表明,坞内静态条件下转轴倾角估计误差标准差分别为0.96″和0.82″,海上航行条件下转轴倾角估计误差标准差分别为1.04″和0.90″,海上动态估计精度与静态条件下相当,验证了所提方法的有效性。

老旧城区排水管道地箭式微顶管技术应用研究——以武汉市老城区改造为例

以武汉市历史风貌区老旧城区排水改造工程为背景,对复杂地质下地箭式微型顶管施工进行分析研究,介绍了微型顶管技术的工艺原理,重点阐述了微型顶管技术在城市排水改造工程中的施工工艺及控制措施,提出了高压旋喷桩止水帷幕+洞口橡胶止水装置以及触变泥浆智能注浆系统对流沙、涌泥的防治方法,切实解决了传统开槽法排水管道施工的不足,为类似工程施工提供借鉴。

一种红外经纬仪-雷达引导方法的设计与研究

光学经纬仪和弹道雷达都是重要的靶场测试设备。针对弹道雷达在目标飞行初始段存在盲区无法短时间捕获目标的问题,提出在弹道坐标测量过程中主动段光学经纬仪实时交会引导雷达跟踪目标,中末段弹道雷达引导经纬仪对目标继续成像的经纬仪-雷达配合跟踪策略,从而克服单一传感器的局限和不足。开展了理论分析并设计实地实验,验证方法的可行性和有效性,为提升空中目标跟踪标捕获率和丰富靶场弹道坐标测量方法手段提供借鉴和参考。

舰载光电经纬仪动态标校方法

针对舰载光电经纬仪标校过程复杂、标校条件要求严苛的问题,提出一套舰载光电经纬仪标校方法。该方法在通过装舰前的陆基标校,装舰后的艏艉线标校以及拍星标校修正了光电经纬仪、惯性导航系统与舰船的坐标系转换矩阵,进而提升装备的空间指向精度。该标定方法操作简便,可在舰船动态条件下进行,能有效地完成光电经纬仪的标校工作,提高设备的安装效率。实装结果表明,采用该方法标校后的舰载光电经纬仪的实时空间指向精度优于20″。

塔式起重机垂直度激光雷达无损检测算法

针对传统的经纬仪测量法存在的诸多弊端,本文提出一种新的塔式起重机垂直度激光雷达无损检测算法。利用激光雷达获取塔式起重机点云数据,经点云配准、拼接及去噪去冗等预处理,获得塔身标准节有效点云数据;设计塔身标准节点云横截面切片分割方案,利用Marching Square算法提取切片多边形轮廓线,并确定轮廓线顶点及其对应的中心点坐标;利用最小二乘参数估计法拟合中心点空间直线,确定塔身轴心线方向向量,并与站心空间坐标系的z轴和x轴分别作向量运算,求解塔身轴心线的倾斜角、倾斜方位角及垂直度参数。试验结果表明,基于本文算法设计的两种方案获得的塔式起重机垂直度参数分别为2.04‰和2.49‰,均小于传统的经纬仪测量法的3.02‰。本文算法行之有效,为塔式起重机垂直度高精度监测提供了一种无损检测算法。

使用经纬仪与平行光管测量转台测角误差

介绍了一种使用经纬仪与平行光管进行检测转台测角误差的测量方法,并对其实施细节进行了讨论。使用棱体和自准直仪的检测方法测量准确度高且稳定可靠,但存在成本高、测量点数受限和操作繁琐等缺点。该方法通过利用经纬仪作为测角标准器,平行光管作为无穷远目标实现准确的角度测量。通过准确调整平行光管分划板位置和经纬仪与转台的同轴性,尽可能减小测量误差。实验结果表明,该方法与常规方法结果一致性好,同时具有成本低廉、操作简便和可测量任意角度等优点。