scholarly journals Positioning Accuracy of Single Frequncy GNSS PPP by CLAS Comparing with MADOCA Products

Author(s):  
Dai Mimura ◽  
Katsumasa Miyatake ◽  
Yukihiro Kubo ◽  
Sueo Sugimoto
Keyword(s):  
Author(s):  
V.V. Kostenko ◽  
Yu.V. Vaulin ◽  
F.S. Dubrovin ◽  
O.Yu. Lvov

Буксируемый подводный модуль (БПМ) эффективно используется для решения задач, связанных с координированием подводных объектов, местоположение которых подлежит уточнению в процессе их детальногообследования. При этом большое значение имеет точность определения координат самого буксируемогомодуля относительно судна-буксировщика. Использование гидроакустических навигационных средств, вчастности систем с ультракороткой базой (ГАНС УКБ), ограничено вследствие помех, влияющих на качествосигналов в приемной антенне. Альтернативой служит метод определения координат БПМ на основе данныхтраекторных измерений параметров буксируемой системы. К числу последних относятся расчетные значенияпараметров кабеля связи в установившихся режимах буксировки, значения путевой скорости и путевого углабуксировщика, а также измеренные значения длины кабеля, глубины погружения и курса БПМ. В работе дансравнительный анализ различных вариантов вычислительных алгоритмов, позволяющих получить оценки точности определения координат БПМ в различных режимах стационарной буксировки и при наличии сбоев вработе навигационных средств.The towed underwater module (TUM) is a useful toolfor solving problems of the positioning of the underwaterobjects, the location of which must be clarified during its detailedinspection. Herewith, the accuracy of the determinationof the coordinates of the towed module itself relative tothe towing vessel is essential for such kind of problems. Theuse of underwater acoustic navigation means, the systemswith ultra-short baseline (USBL) in particular, are limiteddue to interference affecting the quality of the signals on thereceiving antenna. As an alternative, the method is proposedfor TUM positioning based on trajectory measurements ofparameters of the towed system, which may include calculatedvalues of communication cable parameters in steadystatetowing modes, values of ground speed and towing angle,as well as measured cable length, immersion depth, andTUM heading. The paper provides a comparative analysisof various versions of computational algorithms, which allowobtaining estimates of the TUM positioning accuracy indifferent modes of stationary towing and in the presence offailures in navigation systems operation.


Author(s):  
Мурат Газизович Мустафин ◽  
Глеб Андреевич Фролов

В данной работе рассмотрен принцип работы созданного алгоритма, позволяющего автоматически определять среднюю квадратическую погрешность планового положения пунктов сетей трилатерации и представлены результаты автоматизации данного процесса при различных конфигурациях сети, с использованием пакетов Microsoft Excel, Visual Basic for Applications. This paper presents automatic solution for evaluating accuracy of positioning for specialized networks’ points in a plane coordinate system. The paper presents results of automation of this process through analysis of multiple configurations of trilateral networks using Microsoft Excel, Visual Basic for Applications.


2015 ◽  
Vol 809-810 ◽  
pp. 682-687
Author(s):  
Vasile Nasui ◽  
Mihai Banica ◽  
Dinu Darabă

This paper presents the dynamic characteristics and the proposed positioning performance of the system to them investigated experimentally. In this research, we developed the positioning system and we evaluated positioning accuracy. The developed system uses a servo motor for motion actuation. In this paper, we focused on studying the dependency of the positioning error – elementary errors – the position of the conducting element for the mechanism of the transformation of the rotation translation movement, representatively the mechanism screw – screwdriver and on emphasizing the practical consequences in the field of design, regulation and exploitation of the correct identification of all the initial errors in the structure of the mechanism, their character and the selection for an ultimate calculus of these which are of a real practical importance.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jaqueline Stauffenberg ◽  
Ingo Ortlepp ◽  
Ulrike Blumröder ◽  
Denis Dontsov ◽  
Christoph Schäffel ◽  
...  

Abstract This contribution deals with the analysis of the positioning accuracy of a new Nano Fabrication Machine. This machine uses a planar direct drive system and has a positioning range up to 100 mm in diameter. The positioning accuracy was investigated in different movement scenarios, including phases of acceleration and deceleration. Also, the target position error of certain movements at different positions of the machine slider is considered. Currently, the NFM-100 is equipped with a tip-based measuring system. This Atomic Force Microscope (AFM) uses self-actuating and self-sensing microcantilevers, which can be used also for Field-Emission-Scanning-Probe-Lithography (FESPL). This process is capable of fabricating structures in the range of nanometres. In combination with the NFM-100 and its positioning range, nanostructures can be analysed and written in a macroscopic range without any tool change. However, the focus in this article is on the measurement and positioning accuracy of the tip-based measuring system in combination with the NFM-100 and is verified by repeated measurements. Finally, a linescan, realised using both systems, is shown over a long range of motion of 30 mm.


2021 ◽  
pp. 1-17
Author(s):  
Yixu Liu ◽  
Xiushan Lu ◽  
Shuqiang Xue ◽  
Shengli Wang

Abstract The layout of seafloor datum points is the key to constructing the seafloor geodetic datum network, and a reliable underwater positioning model is the prerequisite for achieving precise deployment of the datum points. The traditional average sound speed positioning model is generally adopted in underwater positioning due to its simple and efficient algorithm, but it is sensitive to incident angle related errors, which lead to unreliable positioning results. Based on the relationship between incident angle and sound speed, the sound speed function model considering the incident angle has been established. Results show that the accuracy of positioning is easily affected by errors related to the incident angle; the new average sound speed correction model based on the incident angle proposed in this paper is used to significantly improve the underwater positioning accuracy.


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