机载三线阵CCD摄影测量的直接解算模型与精度分析

机载三线阵CCD摄影测量系统是GPS/INS与三线阵CCD相机联合工作的测量系统.通过GPS/INS给出的投影中心位置、视准轴姿态观测值及三线阵CCD像空间坐标,可以直接计算地面点在物空间的坐标.介绍了直接解算的几何模型,并依据共线方程建立地面点像空间坐标与控制点或同名点物空间坐标的关系,从而把问题归结为间接平差,给出了平差的误差方程.最后对直接解算模型进行了精度分析.     

基于自标定技术的相机内方位元素测试影响因素分析

内方位元素测试精度对于航天相机至关重要,可以有效提高图像的几何质量,需作重点分析。传统航天相机内方位元素标定方法一般采用光电精密测角法,该测试方法通过旋转相机的方式实现高精度的内方位元素和畸变测试,对测试设备的精度和承重要求较高,具有应用局限性。相机自标定技术方法灵活,仅需建立图像点和网格板角点之间的对应关系,无需复杂、精密的测试设备便可直接求解出内方位元素。本文从自标定算法的推导中,分析基于自标定技术的内方位元素测试精度的影响因素,通过实际标定试验归纳出达到理想标定精度时各个影响因素的最优值。     

基于Ubuntu的GAMIT/GLOBK快速安装与实例解算

针对GAMIT/GLOBK软件安装较为复杂、基线解算较为烦琐的问题,本文基于VMware Workstation 12.05虚拟机和Ubuntu 16.04操作系统,较为翔实地介绍了如何流程化快速安装GAMIT/GLOBK 10.7软件,并利用中国境内IGS站的观测数据进行了实例数据处理.本文在验证软件安装正确性的同时...     

消费级惯性传感器动态系统误差分析与建模

针对传统的系统误差转台标定方法耗时耗力且受限于实验地点的问题,该文从载体运动特征的角度,使用高精度战术级惯性导航设备作为参考,采集车载动态数据,通过传统传感器信号误差模型对消费级低成本惯性导航设备在线标定后,对标定后的观测值残差分别与载体运动角速度、角加速度、角冲击(加速度导数)、线性加速度、线性加速度冲击进行相关性分...     

GAMIT/GLOBK 10.7与Bernese 5.2陆态网数据解算结果对比分析

由于全球卫星导航系统(GNSS)技术广泛应用,各个领域行业对GNSS数据处理的精度和效率提出了更高要求,本文基于GAMIT/GLOBK 10.7与Bernese 5.2软件对中国大陆构造环境监测网络(CMONOC)观测数据进行解算,并对解算策略的确定和解算结果进行对比分析,实验结果表明:GAMIT 10.7和Berne...     

基于GNSS/传感器铁道施工维护人员安全监测与预警系统的设计

铁道施工维护人员安全监测与预警系统集成了GNSS CORS、雷达、网络传输、计算机等先进技术,实现了铁路快速预警。根据实际情况,既能提高工作效率、增加经济效益,又能保障维护人员的安全,以实现高铁维护的智能化、网络化、实时化和精准化的监测和预警。     

GPS/INS紧组合导航姿态计算方法选取分析

基于GPS/INS紧组合模式, 研究了方向余弦算法和四元数算法的解算过程, 并通过模拟数据试验, 分析了它们在姿态解算过程中对姿态漂移误差的影响。通过对比可以得出, 四元数法在相同模拟环境和相同解算阶数下, 其姿态解算精度要优于方向余弦算法, 且所用参数和约束方程均少于方向余弦算法。     

基于GPS/INS姿态测量与定位的航空摄影测量精度分析

OEEPE于1999年启动了名为"集成传感器定向"的实验,研究"是否或在什么条件下GPS/INS直接测量的外方位元素可完全替代空中三角测量"这一焦点问题.对本次OEEPE实验的设立、数据获取与预处理以及"直接传感器定向"与"集成传感器定向"两个阶段的主要内容、输入数据与结果进行了全面系统的介绍,总结了该实验若干关键性的结论,以指导基于GPS/INS系统的航空摄影测量作业生产.     

武汉市近20年土地利用/覆被变化遥感监测与分析

为探究武汉市土地利用时空变化特征,基于Landsat遥感影像数据,从土地利用动态度、土地利用状态指数两个方面分析了武汉市2000—2019年的土地利用时空变化格局.结果表明:①武汉市水域面积直线下降,下降速度较稳定,平均年缩减率为1.76％;而建设用地面积逐年增加,由市中心向四周呈"辐射式"扩张,增速逐渐减缓;②耕地和...     

Insights into the affine model for high-resolution satellite sensor orientation

As a model for sensor orientation and 3D geopositioning for high-resolution satellite imagery (HRSI), the affine transformation from object to image space has obvious advantages. Chief among these is that it is a straightforward linear model, comprising only eight parameters, which has been shown to yield sub-pixel geopositioning accuracy when applied to Ikonos stereo imagery. This paper aims to provide further insight into the affine model in order to understand why it performs as well as it does. Initially, the model is compared to counterpart, ‘rigorous’ affine transformation formulations which account for the conversion from a central perspective to affine image. Examination of these rigorous models sheds light on issues such as the effects of terrain and size of area, as well as upon the choice of reference coordinate system and the impact of the adopted scanning mode of the sensor. The results of application of the affine sensor orientation model to four multi-image Ikonos test field configurations are then presented. These illustrate the very high geopositioning accuracy attainable with the affine model, and illustrate that the model is not affected by size of area, but can be influenced to a modest extent by mountainous terrain, the mode of scanning and the choice of object space coordinate system. Above all, the affine model is shown to be both a robust and practical sensor orientation/triangulation model with high metric potential.     

Error analysis of exterior orientation elements on geolocation for a Moon-based Earth observation optical sensor

ABSTRACT

The Moon is a potential new platform for Earth observation. The advantages of its large-scale observational scope, long temporal duration, and multi-layer detecting of the Earth will undoubtedly advance our understanding of the Earth system. To carry out the observations from a Moon-based optical sensor, the geolocation error caused by exterior orientation elements need to be investigated. This paper analyses the error effects of exterior orientation elements on geolocation for an optical sensor. To estimate the error, we present a geometric image model and utilise some parameters to measure the image offsets. Through a large number of numerical simulations, the results demonstrate that the image offsets are not obvious influenced by the distance and observation angle at mid-high latitude of the Moon and have linear correlation with the increasing errors of the exterior orientation elements. Further, the relationship between the spatial resolution and errors of exterior orientation elements are revealed. Finally, the error characteristics for Moon-based Earth observation are discussed. It is expected that the conclusion drawn in this paper could support the study of a Moon-based Earth observation optical sensor.     

一种非共线TDI CCD成像数据内视场拼接方法

星载非共线TDI CCD成像数据的高质量内视场拼接是保证影像后续处理和应用的基础。本文提出了一种非共线TDI CCD成像数据内视场拼接方法,该方法基于物方投影面和相机的传感器几何模型,建立了从拼接影像像点到原始影像像点的坐标转换关系,进而采用间接法影像纠正的方式对原始影像进行重采样生成拼接影像。本文在描述非共线TDI CCD严格成像几何模型之后,详细叙述了方法的基本原理、潜在的误差来源以及方法的实现流程,并通过ZY-1 02C卫星的高分辨率（HR）相机成像数据进行了试验验证,对拼接精度的分析与评价证明了方法的可行性。     

高分辨率遥感卫星传感器严格成像模型的建立及验证

本文对高分辨率遥感卫星传感器严格成像模型进行了深入研究。分析了星载线阵CCD传感器严格成像模型的一般建立方法与过程,针对SPOT 5 HRS/HRG、ALOS PRISM、资源三号TLC等典型的高分辨率遥感卫星传感器特点,分别给出了3种改化的严格成像模型;设计了基于光束法区域网平差的模型验证方法。利用登封遥感实验场区域的3种卫星影像及相关辅助数据,对严格成像模型的正确性进行了验证。结果表明3种改化模型可有效实现卫星影像的平差定位。     

GPS/IMU组合定位定向系统设计

介绍了一种组合低成本的GPS和IMU(Inertial Measurement Unit)来获得高精度姿态、位置和速度信息的方法。文中介绍了GPS／IMU组合系统的设计方案及系统的硬件和软件设计，并给出了实验结果。该组合系统将来安装于炮兵测地车后，不仅可以提高测地的精度，而且在采样率、可靠性等方面比单独采用GPS定位的方法更有优势。     

一种发射车快速精确定位定向技术的研究

目前发射车的定位定向普遍采用GPS、惯导及寻北仪等测量方法或后方交汇解算方法。测量法易受干扰、精度低而且寻北时间长;而解算法没有研究经纬仪存在姿态倾角时测量点三维坐标及载体姿态角的求解问题。本文提出了一种新的导弹发射车快速精确定位定向的方法:首先利用捷联安装在车体上的光电探测器,分别探测地面上三个坐标位置已知的靶标,得到三组方位角和俯仰角,并结合车载导航设备给出的发射车概略坐标、姿态角信息解算出发射车更精确的坐标、姿态角。通过实验研究论证,表明此方法具有速度快、精度高、自动化及智能化程度高的特点,能够有效缩短发射车准备时间、提高导弹发射的反应速度。     

Comparison of two physical sensor models for satellite images: Position–Rotation model and Orbit–Attitude model

The main objective of this paper is to compare two types of physical sensor models of linear pushbroom satellite images: one that uses position and rotation angles as model parameters and one that uses orbit and attitude angles as model parameters. Comparison is carried out by two accuracy measures: the accuracy of bundle adjustments and the accuracy of estimating exterior orientation parameters. The first measure has been used widely to indicate the mapping accuracy of sensor models. It is argued that the second measure is also important for certain applications. The two types were implemented with different sets of unknown parameters and tested with two KOMPSAT-1 Earth Observing Camera (EOC) scenes and GPS-derived control points. In terms of the first measure the two models produced similar results whereas in terms of the second measure the one based on orbit and attitude outperformed the other. It seems better to use this model if one wishes to retrieve satellite orbit or attitude through bundle adjustments.     

基于先验求权的虚拟观测值法及其在线阵影像定向中的应用

航天线阵列遥感影像定向参数之间存在强相关性,参数解算不稳定,难以得到准确结果。较为常见的解决方法是将定向参数处理成虚拟观测值或用岭估计代替最小二乘估计。本文首先分析了这两种方法的联系与区别,提出利用原始外方位元素精度等先验知识给定虚拟观测值权,进一步提高定向结果的可靠性。对SPOT-5与QuickBird两种高分辨率线阵影像的定向试验结果表明,在使用6个分布良好的地面控制点情况下,影像对地目标定位精度可达到2~4个像素的水平。