机载三维成像仪的定位原理与误差分析

本文论述了“机载三维成像仪”的定位原理,并在系统定位原理的基础上,详细讨论了与“机载三维成像仪”的对地定位精度有关的传感器的误差对系统定位精度的影响,这一问题的研究不仅对研制针对不同目的的激光地形制图系统的设计具有指导意义,而且对激光扫描制图系统的数据平差具有重要意义。     

机载三维成像仪航带拼接的误差处理研究

机载三维成像仪是集成了全球定位系统（GPS）、姿态测量装置、激光测距仪昨光谱成像仪的新一代航空遥感系统，它能直接得到的地学编码影像和数字地面模型（DTM），而无需地面控制点。利用图像上分布的具有三维坐标的激光点来纠正原始图像，并且生成DTM。该文首先分析了机载三维成像仪系统中各种传感器本身的误差和系统之间存在的误差，然后介绍了处理系统误差的方法－航带重叠区域灰度平均差值最小算法求解航带间的系统误差，同时还设计了一种变权方法来处理随机误差和拼接航带的地学编码图像。通过算例说明了处理算法的正确性。     

机载激光测距-扫描成像制图系统的定位原理与误差分析

阐述了遥感直接对地定位的基本原理,在此基础上分析影响机载激光测距-扫描成像制图系统对地定位精度的各种因素,最后给出了在不同情况下同一条扫描线上不同位置的对地定位精度的特征。     

机载激光测距—扫描成像制图系统的定位原理与误差分析

阐述了遥感直接对地定位的基本原理,在此基础上分析影响机载激光测距－扫描成像制图系统对地定位精度的各种因素,最后给出了在不同情况下同一条扫描线上不同位置的对地定位精度的特征。     

机载三维成像仪数据的快速处理技术

对数据的快速处理技术进行了全面分析,包括数据的检测分解、GPS数据解算、计算激光采样点三维位置、地学编码图像的生成、DEM的快速生成和航带的自动拼接等算法。最后通过在浦东所获取的数据进行快速处理,表明了数据处理技术是可行的,基本可以满足准实时的应用要求。     

机载三维成像仪数据的快速处理技术

对数据的快速处理技术进行了全面分析,包括数据的检测分解、ＧＰＳ数据解算、计算激光采样点三维位置、地学编码图像的生成、ＤＥＭ的快速生成和航带的自动拼接等算法。最后通过在浦东所获取的数据进行快速处理,表明了数据处理技术是可行的,基本可以满足准实时的应用要求。     

机载激光雷达对地定位误差分析

简要介绍了机载激光雷达的发展现状。依据机载激光雷达对地定位的基本原理,在综合分析几大误差源的基础上,推导了对地定位综合误差模型。并根据现有机载激光雷达的精度参数,对不同误差源的影响进行了定量分析,得出了一些有益的结论。     

基于机载三维成像仪快速获取数字地面模型

机载三维成像仪是集成GPS、姿态测量装置、激光测距仪和光谱成像仪的新型航空遥感系统，它能同步获取地面目标的定位、定性数据。本文简要介绍了机载三维成像仪系统，在计算出扫描激光测距点三维坐标的基础上，着重分析了DTM快速生成算法，包括DTM的快速内插和航带间的自动无缝拼接。     

低空机载LiDAR点云定位误差分析

低空机载LiDAR因其系统的复杂性,点云定位精度受很多系统误差影响。为了研究改善点云定位精度的方法,文中根据LiDAR定位误差模型综合分析航高、扫描角、IMU姿态角、姿态角误差等对点云定位误差的影响,并根据误差影响规律分析得出不同地形测图比例尺对飞行参数的要求。通过长江中下游实测地区作业验证,建议设置飞行参数得到的点云定位精度符合精度要求。     

利用机载三维成像仪的DSM数据自动提取建筑物

利用三维成像仪获取的DSM作为数据源,首先采用影像分割得到建筑物的平面轮廓线,再根据建筑物一般具有规则平面形状的特点,对建筑物的平面边缘线进行规格化处理,最后求出建筑物的平均高度值,从而得到建筑物的三维信息。试验表明,该方法是实用的。     

机载LiDAR定位精度分析

介绍机载激光雷达测量技术,根据测量的几何原理推导定位方程。讨论定位的误差来源,建立误差模型并对误差影响进行分析。综合各项因素的影响,将模拟数据代入误差传播公式,计算定位精度。     

机载LiDAR系统定位方程、误差分析与精度评定

本文从机载LiDAR系统几何定位方程出发、基于误差传播规律推导了机载LiDAR系统的综合误差计算公式,分别研究了IMU测角、GPS、激光测距、扫描角等多种误差源对激光脚点定位精度的影响规律,从理论上分析了机载LiDAR系统定位精度.本文的结果对实际应用具有重要的参考价值.     

一种高精度轻小型航空遥感系统的集成与应用

高精度轻小型航空遥感系统是一种灵活高效的遥感数据获取手段。本文将高精度大负载惯性稳定平台、高精度位置姿态测量系统、高精度组合宽角数字航测相机和动力伞集成为一种轻小型航空遥感系统,并进行了大比例尺遥感测绘和大型露天矿遥感监测应用航拍试验。经过对采集到的数据进行处理和分析,试验结果满足规范要求。     

The design and the development of a hyperspectral and multispectral airborne mapping system

Flexible and cost-effective tools for rapid image acquisition and natural resource mapping are needed by land managers. This paper describes the hardware and software architecture of a low-cost system that can be deployed on a light aircraft for rapid data acquisition. The Hyperspectral and Multispectral Cameras for Airborne Mapping (HAMCAM) was designed and developed in the Geospatial Laboratory for Environmental Dynamics at the University of Idaho as a student-learning tool, and to enhance the existing curriculum currently offered. The system integrates a hyperspectral sensor with four multispectral cameras, an Inertial Navigation System (INS), a Wide Area Augmentation System (WAAS)-capable Global Positioning System (GPS), a data acquisition computer, and custom software for running the sensors in a variety of different modes. The outputs include very high resolution imagery obtained in four adjustable visible and near-infrared bands from the multispectral imager. The hyperspectral sensor acquires 240 spectral bands along 2.7 nm intervals within the 445–900 nm range. The INS provides aircraft pitch, roll and yaw information for rapid geo-registration of the imagery. This paper will discuss the challenges associated with the development of the system and the integration of components and software for implementation of this system for natural resource management applications. In addition, sample imagery acquired by the sensor will be presented.     

车载移动测量系统点云精度评定方法

为了对车载移动测量系统点云精度进行客观准确的评价,该文提出了利用室外三维检测场,借助自制的反射纸、球形靶标和特征地物,获取特征点的高精度三维坐标和特征线的长度值,通过与系统解算出来的结果进行比对,评价了系统的绝对精度、相对精度和重复性精度。试验结果表明,该文提出的方法可以对厘米级车载移动测量系统进行点云精度评定,方法切实可行,为相关检测标准的制定提供技术支持。     

Investigation for planimetric accuracy of airborne synthetic aperture radar

The airborne SAR images were tested for geometric accuracy in order to assess the suitability of present airborne radar systems for topographic mapping. Images were transformed to terrain coordinate system using 2-D conformal, affine and polynomial transformations. Standard error in positional discrepancies at check points show that the geometric fidelity of present airborne SAR system is compatible with planimetric mapping requirements at 1∶50,000 and smaller scale.     

Real-time registration of airborne laser data with sub-decimeter accuracy

This paper presents a methodology for the precise registering of airborne laser data directly in flight with an accuracy that is sufficient for the majority of derived products, such as digital terrain models. We first present the strategy that integrates GPS/INS/LiDAR data for generating laser point clouds directly in flight and analyzes their accuracy. The latter requires the implementation of a functional covariance propagation on-line for all the system components (i.e. trajectory, laser, system calibration) to which influences of scanning geometry are added at the end of a flight line. The study of scanning geometry necessitates the classification of vegetation and coarse estimation of the terrain normal. This is achieved by a method that we formerly proposed for off-line quality analysis. The second part of the paper focuses on the positioning component. In high resolution scanning performed close to the terrain, the absolute accuracy of the resulting point cloud depends mainly on the quality of the trajectory which is related to the type of GPS solution (e.g. absolute positioning, DGPS, RTK). To reach sub-decimeter accuracy for the point cloud in the real-time, an RTK-GPS solution is needed. This requires the establishment of a communication link for the transmission of GPS corrections (or measurements). We analyze the usability of RTK-GPS/ALS acquired during several flights using different communication methods in the particular context of helicopter based missions. We focus mainly on the exploitation of nation-wide reference GNSS networks and confirm experimentally that the real-time registration of airborne laser data is feasible with sub-decimeter accuracy. Such quality is sufficient not only for a wide range of applications, but it also opens new opportunities for monitoring missions that require a short reaction time. Finally, we concentrate on situations when the phase and code corrections cannot be transmitted, and the quality of the differential carrier-phase positioning needs to be predicted. We validate the previously introduced indicators of positioning quality by simulated degradation of the input data.     

机载合成孔径雷达技术在地形测绘中的应用及其进展

合成孔径雷达(SAR)技术由于其全天候、全天时的工作能力,成为近几年来摄影测量与遥感领域的研究热点。机载SAR系统的逐渐增多为SAR技术的发展提供了丰富的数据源。本文综述了近两年来国内外机载合成孔径雷达(AIRSAR)技术在地形测绘中的研究、试验和应用进展,评述了机载合成孔径雷达关键技术的解决途径,展望了机载合成孔径雷达技术在地形测绘和其他领域中的应用前景。