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K. P. Schwarz 《Journal of Geodesy》1985,59(1):33-54
The outpout of inertial survey systems is available to the user in two basic forms: as Kalman filtered information at updates or as integrated velocity and position information at regular time intervals. In case of the second data type, the post-mission processing starts with the approximation of the velocity error curve. This approximation is either based on a system error model as in Kalman filtering or uses curve fitting techniques. From there on, smoothing or adjustment procedures are used as further steps in the post-mission treatment of both data types. A unified treatment of the various post-mission approaches starts with the formulation of appropriate error models of the system outputs. It is then possible to present all existing methods as intermediate steps of a rigorous adjustment procedure. This unified approach gives insight into the limitations of individual methods and provides a means to detect inconsistencies in post-mission processing strategies. An analysis of existing approaches is made and a new method, spectral decomposition, is treated in detail. Compared to the existing procedures, it has advantages with respect to a rigorous covariance propagation and blunder detection. 相似文献
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Present day inertial surveys are limited to single traverse runs in which the number of unknown system parameters to be determined
are few, depending on the number of control points available along the traverse. Further, conventional inertial surveys are
generally restricted to the determination of coordinates with no possibility for a rigorous post-mission adjustment of the
observations. The consequence is the continued presence of systematic trends in the residuals, even after the use of error
models such as those proposed by Ball, Gregerson or Kouba. Future work aiming at higher accuracies obviously requires more
comprehensive models and rigorous adjustment procedures. These can be accomplished by the development of such error models
and by the use of “area surveys”, instead of the single traverses, together with rigorous adjustment procedures suitable for
the network of criss-crossing lines inertially surveyed. In such a network the cross-over points serve as constraints for
the geodetic parameters (latitude, longitude, height, gravity anomaly, deflection components) and allow the addition of hardware
and software related error parameters. Thus an opportunity is provided to effectively self-calibrate the system—a concept
successfully used, for example, in photogrammetry or in satellite tracking. The number and the strength of such parameters
depend on the number of control and cross-over points. The adjustment, of course, also provides the necessary statistical
information on the adjusted parameters, such as their precision and the correlation between them.
The presentation will describe current work at OSU in this area.
Presented at the Second International Symposium on Inertial Technology for Surveying and Geodesy, Banff, Canada, June 1–5,
1981. 相似文献
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YAO Jili WANG Shuguang SUN Yating 《地球空间信息科学学报》2006,9(2):84-88
IntroductionThree coordinate transformation models, Bursa-Wolf, Molodensky and WTUSM[1]are generallyused in 3D coordinate transformation. They are lin-ear models which have seven parametersΔX,ΔY,ΔZ,θ,,ψ[2]. Referecne [2] improved these line-ar mode 相似文献
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GNSS伪距单点定位速度快且不存在整周模糊度问题,其原理简单易于编程实现,所以在进行GNSS数据处理时,经常用到该方法。本文以GPS、GLONASS、BDS多模融合为例,简单介绍多模融合存在的坐标统一、时间基准统一问题,再详细介绍多模融合伪距单点定位原理以及解算模型,基于Visual Studio2010平台,编写GPS、GLONASS、BDS多模融合的伪距单点定位及单点测速程序。结合相关算例,对该程序多系统伪距单点定位的精度以及单点测速精度进行分析。 相似文献
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In this paper, a transformation model named SARC (static-filter adjustment with restricted condition) is presented, which is more practical and more rigorous in theory and fitting any angle of rotation parameter. The transformation procedure is divided into 4 steps: ¹ the original and object coordinates can be regarded as observations with errors: ² rigorous formula is firstly deduced in order to compute the first approximation of the transformation parameters by use of four common points and the transformation equation is linearized; ³ calculate the most probable values and variances of the seven transformation parameters by SARC model; {ie84-1} to demonstrate validity of SARC, an example is given. 相似文献
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针对车载全球导航卫星系统/惯性导航系统(global navigation satellite system/inertial navigation system,GNSS/INS)组合导航中卫星信号中断,惯性导航系统单独导航误差积累较大的问题,提出了附加载体运动条件约束的卡尔曼(Kalman)滤波解算方法。通过利用载体固有的运动约束,包括近似高程约束、近似速度约束和近似姿态约束,减少载体自由度和模型参数;通过引入新的观测类型,增加观测冗余,可以加强Kalman滤波解,提高在GNSS信号中断时组合导航系统的定位精度,实现无缝导航。 相似文献
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A new method to mitigate multipath error in single-frequency GPS receiver with wavelet transform 总被引:2,自引:1,他引:1
One of the major errors in high-precision GPS positioning is multipath. Multipath effect modeling and reduction have been a challenging issue in high-accuracy GPS positioning applications due to its special properties. Different methods have been employed to mitigate this error including hardware and software approaches. We reduce C/A code multipath error by adopting an efficient software method which uses wavelet transform as a basic data processing trend. The key idea of the proposed method is using stationary wavelet transform (SWT) in GPS signal data processing. Since we have used SWT, there is complete access to high-frequency and low-frequency terms in both time and frequency domains, and we can apply appropriated procedures to mitigate this error. The multipath error mostly is a low-frequency term. In our proposed method, the double difference (DD) residuals are applied to the SWT to identify the multipath disturbance. The extracted multipath is then used to correct DD observations. Our experiments include three data sets to investigate the proposed method and compare it with existing algorithms. We used simulations for two of these data sets. The results indicate the efficiency of the proposed method over existing algorithms. 相似文献
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海洋重力测量误差补偿两步处理法 总被引:9,自引:1,他引:9
基于工程化应用的需要,对笔者原来提出的两种海洋重力测量误差补偿方法进行了简化,把原来严密的自检校平差简化为两步处理法,并深入分析了简化方法的技术和适用范围。利用一个实际观测网数据验证了两步处理法的有效性和可靠性。 相似文献
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针对当前高速铁路轨道基准网存在的不足,提出了一种基于3维自由测站交会构网的轨道基准网测量及其数据处理的新方法。首先采用边角网间接平差的严密精度估算方法,对轨道基准网的点间相对精度进行仿真计算;然后结合西南交通大学轨道基准网实验网实测数据,采用自检校3维网平差方法进行数据处理。通过仿真计算和对实验数据的计算分析,认为构网法可以用于轨道基准网3维网测量及其数据处理。而且该方法严谨、效率更优,可供有关部门参照和借鉴。 相似文献
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New optimal smoothing scheme for improving relative and absolute accuracy of tightly coupled GNSS/SINS integration 总被引:1,自引:1,他引:0
For mobile surveying and mapping applications, tightly coupled integration of global navigation satellite system (GNSS) and Strap down Inertial Navigation System is usually recommended for direct georeferencing since it can provide position, velocity, and attitude information at higher accuracy and better reliability in a self-contained manner. A post-mission smoothing method is applied to optimally use observation information of both systems and to overcome the shortcomings of Kalman filter in GNSS degraded environments. We propose the revised Rauch–Tung–Streibel Smoother (RTSS) and Forward–Backward combination (FBC) smoothing algorithms for tightly coupled integration. From the analysis and field test, it is found that RTSS smoothing mainly improves the relative accuracy, while FBC mainly contributes to the absolute accuracy. With the complementary characteristics of both smoothing algorithms, an optimal new smoothing scheme combining RTSS with FBC is built. The performance of these three smoothing algorithms is evaluated through a real vehicular test. Compared with RTSS and FBC smoothing algorithms, the new smoothing scheme improves the mean 3D position RMS and the mean 3D attitude RMS by 65.7 and 70%, respectively. It provides better accuracy and smoothness for the position, velocity, and attitude at the same time. 相似文献
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基于折线逼近的曲线位置与模型误差综合建模 总被引:1,自引:0,他引:1
针对目前GIS中曲线常通过一系列折线来逼近的情况,研究考虑由于折线逼近导致的模型误差和由于测量导致的点位随机误差综合影响的曲线不确定性模型。分析曲线拟合的分段准则,提出折线逼近产生的模型误差可由折线模型到真实曲线的垂直距离描述,建立集成模型不确定性与基于误差传播定律的位置不确定性的曲线误差综合量化模型。 相似文献
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针对基础地理数据更新需求,为了免去外业布设控制点,减少内业刺点工作量,提高控制点精度、密度,提出了一种基于已有DOM和DEM数据,利用IPS软件和辅助软件,实现高精度自动刺像控点的方法。将已有DOM根据具体匹配需求裁切,裁切后的DOM和像片同时加载到IPS中进行同名像点匹配,根据DOM的地理参考、匹配点像平面坐标、TFW头文件及DEM共同解算出匹配点的物方坐标。通过平差探测和目视检查剔除错误点,改变匹配点属性为控制点,即完成了控制点刺入工作。之后可在IPS中继续完成空三处理、地理信息产品制作等,也可导出、转换为其他软件的文件格式,供后续处理使用。 相似文献
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多代卫星测高数据联合平差及重力场反演 总被引:1,自引:0,他引:1
为了解决多代卫星测高数据之间的不协调问题,基于误差验后补偿理论,提出了将传统的交叉点平差整体解法简化为两步处理法,即首先使用条件平差法对交叉点观测方程进行平差计算,然后沿测高轨迹进行海面高滤波和推估。使用新方法可大大简化联合平差的计算过程,且有利于提高计算结果的稳定性和可靠性,对规则和不规则的区域网和全球网交叉点平差问题都同样适用。实际算例证明了新方法的有效性。 相似文献
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József Ádám 《Journal of Geodesy》1982,56(3):180-195
The Euclidean spaces with their inner products are used to describe methods of least squares adjustment as orthogonal projections
on finite-dimensional subspaces. A unified Euclidean space approach to the least squares adjustment methods “observation equations”
and “condition equations” is suggested. Hence not only the two adjustment solutions are treated from the view-point of Euclidean
space theory in a unified frame but also the existing duality relation between the methods of “observation equations” and
“condition equations” is discussed in full detail. Another purpose of this paper is to contribute to the development of some
familiarity with Euclidean and Hilbert space concepts. We are convinced that Euclidean and Hilbert space techniques in least
squares adjustment are elegant and powerful geodetic methods. 相似文献
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