Validation of preliminary geometric positioning accuracy for China’s civil high-resolution surveying and mapping satellites: Ziyuan-3 01 and Gaofen-7 panchromatic imagery

This paper presents on the design, prototyping and testing of a flexure-based active workpiece fixture system for precision robotic deburring. Current industrial robotic manipulators suffer from poor positioning accuracy, which makes precision tasks such as deburring, polishing and grinding challenging. Together, the robotic manipulator and the proposed active work fixture will create a dual-stage positioning system for precision tasks where position/force control is crucial. The main application is robotic deburring, which demands positioning accuracy and high compliance over large cutting forces. This first prototype active fixture system is designed as a planar motion table that is supported by parallel flexures, driven by voice-coil actuators, and uses high-resolution laser displacement pickups facilitate accurate motion generation with great backdrivability for force control. The theory behind the proposed design is shown, and a prototype is then used to validate performance. Overall the prototype flexure stage achieves a total stroke of 1 mm and a bandwidth of 21 Hz.

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Improvement and Assessment of the Absolute Positioning Accuracy of Chinese High-Resolution SAR Satellites

Remote Sensing ◽

10.3390/rs11121465 ◽

2019 ◽

Vol 11 (12) ◽

pp. 1465

Author(s):

Deng ◽

Zhang ◽

Cai ◽

Xu ◽

Zhao ◽

...

Keyword(s):

High Resolution ◽

Propagation Delay ◽

Reference Points ◽

Calibration Model ◽

Land Resource ◽

Positioning Accuracy ◽

Geometric Calibration ◽

Atmospheric Propagation ◽

Absolute Positioning ◽

The Absolute

In recent years, China has launched YaoGan-13 and GaoFen-3, high-resolution synthetic aperture radar (SAR) satellites that can acquire global high-resolution images. The absolute positioning accuracy of such satellites is important for mapping areas without ground reference points and for automated processing. However, satellites without geometric calibration have poor absolute positioning accuracy, greatly restricting their application (e.g., land resource surveys). Therefore, they cannot meet national demands for high-resolution SAR images with good geometric accuracy. Here, we propose a series of methods to improve the absolute positioning accuracy of YaoGan-13 and GaoFen-3, such as the multiple-image combined calibration strategy and geometric calibration model for a real continuously moving configuration, including consideration of atmospheric propagation delay. Using high-accuracy ground control data collected from different areas, the 2-D and 3-D absolute positioning accuracies of YaoGan-13 and GaoFen-3 were assessed after implementation of the improvement measures. Experimental results showed that, after calibration, the 2-D absolute positioning accuracy of YaoGan-13 and GaoFen-3 are improved from 43.86 m to 2.57 m and from 30.34 m to 4.29 m, respectively. In addition, the 3-D absolute positioning accuracies of YaoGan-13 in plane and elevation are 3.21 m and 2.22 m, respectively. Improving the absolute positioning accuracy of these satellites could broaden the scope of their potential applications in the future.

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Preparation of High-Resolution DTM and Orthophoto Using LiDAR in Nepal

Journal on Geoinformatics, Nepal ◽

10.3126/njg.v20i1.39481 ◽

2020 ◽

Vol 20 (1) ◽

pp. 75-80

Author(s):

Abhash Joshi ◽

Sumeer Koirala

Keyword(s):

Economic Development ◽

High Resolution ◽

Digital Terrain Model ◽

Cost Effective ◽

Interval Data ◽

Development Planning ◽

Airborne Lidar ◽

Grid Data ◽

Terrain Model ◽

Surveying And Mapping

The high-resolution terrain model has varied usages including development planning, engineering works, environmental management, disaster management, urban planning, irrigation, geological study, archeological study and cadastral application. Currently, this data is not available for Nepal and it has also hindered the socio and economic development of the country. Airborne Lidar is economically cost-effective and viable means for topography related data collection. Lidar which is an acronym for Light Detection and Ranging is an active remote sensing technology in which Laser beams are used for surveying and mapping. The Survey Department of Nepal has taken initiative to prepare the High-Resolution DTM and Orthophoto of about 20,000 square kilometres of Nepal using Lidar surveying and mapping. Survey Department is conducting a LiDAR survey in the western terai regions of Nepal from Chitwan to Kanchanpur district. Airborne LiDAR survey data along with a very high resolution (0.15 m) orthophoto shall be generated. Further, processing of LiDAR points data will generate a highly precise digital terrain model of 1 m grid data having an accuracy of 0.25 m and finally 0.5 m contour interval data. This endeavor is one of the milestones in the surveying and mapping sector of Nepal and it will have far-reaching consequence in the social and economic development of Nepal.

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IMAGING GEOMETRY AND POSITIONING ACCURACY OF DUAL SATELLITE STEREO IMAGES: A REVIEW

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-annals-iv-2-w4-235-2017 ◽

2017 ◽

Vol IV-2/W4 ◽

pp. 235-242 ◽

Cited By ~ 2

Author(s):

J. Jeong

Keyword(s):

High Resolution ◽

Satellite Data ◽

Experimental Studies ◽

Stereo Images ◽

Positioning Accuracy ◽

Imaging Geometry ◽

Potential Applications

Many previous studies have demonstrated the potential applications of stereo pairs obtained from high-resolution satellites for accurate geo-positioning, but it should be noted that they are based on the conventional use of single-satellite stereo images produced by integrating two images taken by the same satellite. Considering the emergence of various types of satellite data and the requirements to combine these data, it is important to investigate dual-satellite stereo images that integrate two images taken by different satellites. This study reviews the image geometry and positioning accuracy of dual-satellite stereo images based on several important studies, including comparisons with conventional single-satellite stereo images. In particular, the geometric limitation of dual-satellite stereo images often leads to very weak geometry, which degrades the positioning accuracy according to theoretical and experimental studies. Optimal ray intersection can improve the positioning accuracy using dual-satellite stereo images. This review improves our understanding of satellite stereo geometry and the handling of the dual-satellite stereo images, which are expected to become more common in real mapping applications.

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DBSCAN and TD Integrated Wi-Fi Positioning Algorithm

Remote Sensing ◽

10.3390/rs14020297 ◽

2022 ◽

Vol 14 (2) ◽

pp. 297

Author(s):

Jingxue Bi ◽

Hongji Cao ◽

Yunjia Wang ◽

Guoqiang Zheng ◽

Keqiang Liu ◽

...

Keyword(s):

High Resolution ◽

Nearest Neighbor ◽

Reference Points ◽

Manhattan Distance ◽

Support Vector ◽

Indoor Environments ◽

K Nearest Neighbor ◽

Positioning Accuracy ◽

Positioning Algorithm ◽

Accuracy And Stability

A density-based spatial clustering of applications with noise (DBSCAN) and three distances (TD) integrated Wi-Fi positioning algorithm was proposed, aiming to enhance the positioning accuracy and stability of fingerprinting by the dynamic selection of signal-domain distance to obtain reliable nearest reference points (RPs). Two stages were included in this algorithm. One was the offline stage, where the offline fingerprint database was constructed and the other was the online positioning stage. Three distances (Euclidean distance, Manhattan distance, and cosine distance), DBSCAN, and high-resolution distance selection principle were combined to obtain more reliable nearest RPs and optimal signal-domain distance in the online stage. Fused distance, the fusion of position-domain and signal-domain distances, was applied for DBSCAN to generate the clustering results, considering both the spatial structure and signal strength of RPs. Based on the principle that the higher resolution the distance, the more clusters will be obtained, the high-resolution distance was used to compute positioning results. The weighted K-nearest neighbor (WKNN) considering signal-domain distance selection was used to estimate positions. Two scenarios were selected as test areas; a complex-layout room (Scenario A) for post-graduates and a typical large indoor environment (Scenario B) covering 3200 m2. In both Scenarios A and B, compared with support vector machine (SVM), Gaussian process regression (GPR) and rank algorithms, the improvement rates of positioning accuracy and stability of the proposed algorithm were up to 60.44 and 60.93%, respectively. Experimental results show that the proposed algorithm has a better positioning performance in complex and large indoor environments.

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Experimental research of high-resolution AIRSAR in the topography of surveying and mapping

10.1117/12.538557 ◽

2003 ◽

Cited By ~ 1

Author(s):

Zheng Zhao ◽

Jixian Zhang ◽

Ming-hui Yang ◽

Guo-man Huang ◽

Rong-bin Wang

Keyword(s):

High Resolution ◽

Experimental Research ◽

Surveying And Mapping

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The Error Analysis of GPS-RTK Construction Stakeout

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.655-657.1884 ◽

2013 ◽

Vol 655-657 ◽

pp. 1884-1888

Author(s):

Jin Hong Xu ◽

Ruo Li Yang ◽

Bei Bei Zhang

Keyword(s):

Error Analysis ◽

Real Time ◽

External Environment ◽

Positioning Error ◽

Positioning Accuracy ◽

Gps Rtk ◽

Satellite Signal ◽

The Impact ◽

Surveying And Mapping

GPS-RTK technology with real-time , high positioning accuracy and easy to operate features, is widely used in the filed of surveying and mapping; With the improvement of RTK technology, the initialize speed , results accuracy and reliability of the RTK survey will be increasingly higher.Due to the impact of the satellite signal and the external environment, the deviation of the RTK positioning and the lack of necessary checking conditions in RTK surveying, this paper will do some researches and analyses about RTK positioning error to serve the Survey and Mapping Engineering better.

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Research of a Driving Equipment for Aero-Engine Rotor Based on FPGA

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.135-136.725 ◽

2011 ◽

Vol 135-136 ◽

pp. 725-731

Author(s):

Li Min Wen ◽

Chang Bao Wen ◽

Yan Ming Li

Keyword(s):

High Resolution ◽

High Accuracy ◽

Experimental Result ◽

Step Motor ◽

Frequency Range ◽

False Detection ◽

Positioning Accuracy ◽

Aero Engine ◽

Engine Blade ◽

Engine Rotor

The positioning accuracy can bring a great impact on inspecting defect for Aero-engine blade. The high or low pressure rotor of engine is generally driven by manual when blade’s defect is inspected. Frequently，False detection and missed happens due to match failure between two persons. Adopting a high-resolution, high-accuracy algorithm based on FPGA to design automotive equipment for high or low rotor . The Frequency range to step motor is 1Hz / s to 65536Hz / s, resolution is 1Hz,and positioning accuracy for blade can be up to 1mm.Resolving the questions of missing detectable rates made by manual during inspection in the paper, and increasing efficiency for inspection and the reliability of the experimental result. Experiment results show that this equipment can meet the challenge of the high-accuracy regulating speed for blade’s inspection.

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CADASTRAL POSITIONING ACCURACY IMPROVEMENT: A CASE STUDY IN MALAYSIA

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-4-w1-265-2016 ◽

2016 ◽

Vol XLII-4/W1 ◽

pp. 265-270

Author(s):

N. M. Hashim ◽

A. H. Omar ◽

K. M. Omar ◽

N. M. Abdullah ◽

M. H. M. Yatim

Keyword(s):

Information System ◽

Coordinate System ◽

Geographical Information System ◽

Geographical Information ◽

Positional Accuracy ◽

Accuracy Improvement ◽

Positioning Accuracy ◽

Digital Map ◽

Surveying And Mapping

Cadastral map is a parcel-based information which is specifically designed to define the limitation of boundaries. In Malaysia, the cadastral map is under authority of the Department of Surveying and Mapping Malaysia (DSMM). With the growth of spatial based technology especially Geographical Information System (GIS), DSMM decided to modernize and reform its cadastral legacy datasets by generating an accurate digital based representation of cadastral parcels. These legacy databases usually are derived from paper parcel maps known as certified plan. The cadastral modernization will result in the new cadastral database no longer being based on single and static parcel paper maps, but on a global digital map. Despite the strict process of the cadastral modernization, this reform has raised unexpected queries that remain essential to be addressed. The main focus of this study is to review the issues that have been generated by this transition. The transformed cadastral database should be additionally treated to minimize inherent errors and to fit them to the new satellite based coordinate system with high positional accuracy. This review result will be applied as a foundation for investigation to study the systematic and effectiveness method for Positional Accuracy Improvement (PAI) in cadastral database modernization.

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