The Use of UAV Photogrammetric Technology in Order to Make the Cadastral Documentation of Detachment in Two Lots of a Property Located in Valea Ierii, Cluj County

The cadastre and the land book form a unitary and mandatory system that ensures technical, economic and legal records of all the properties on the territory of the country. This paper includes the presentation of the operations necessary to prepare the cadastral documentation for detachment in two lots, using UAV photogrammetric technology. The studied area is located in the suburbs of Valea Ierii locality, with an area of 212353 sqm. The main part of the project was based on the use of the UAV photogrammetric method to survey the area. At the same time, two GNSS receivers were used to complete the photogrammetric measurements. Control and verification points were premarked on the ground, the coordinates of which were determined by the real-time kinematic GNSS method. This operation was followed by performing the photogrammetric flight using an UAS platform. The flight lasted about 17 minutes, covered an area of 29 ha and 288 frames were captured. The front overlap between photos was set to 75% and the side overlap to 65%. New technologies for taking frames and processing them have been adopted, through methods that involve a low cost and a shorter time to perform specific operations.

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Positioning Accuracy Comparison of GNSS Receivers Used for Mapping and Guidance of Agricultural Machines

Agronomy ◽

10.3390/agronomy10070924 ◽

2020 ◽

Vol 10 (7) ◽

pp. 924 ◽

Cited By ~ 3

Author(s):

Pietro Catania ◽

Antonio Comparetti ◽

Pierluigi Febo ◽

Giuseppe Morello ◽

Santo Orlando ◽

...

Keyword(s):

Real Time ◽

Precision Agriculture ◽

Low Cost ◽

Global Navigation Satellite Systems ◽

Reference Trajectory ◽

Positioning Error ◽

Differential Correction ◽

Positioning Accuracy ◽

Real Time Kinematic ◽

Gnss Receivers

Global Navigation Satellite Systems (GNSS) allow the determination of the 3D position of a point on the Earth’s surface by measuring the distance from the receiver antenna to the orbital position of at least four satellites. Selecting and buying a GNSS receiver, depending on farm needs, is the first step for implementing precision agriculture. The aim of this work is to compare the positioning accuracy of four GNSS receivers, different for technical features and working modes: L1/L2 frequency survey-grade Real-Time Kinematic (RTK)-capable Stonex S7-G (S7); L1 frequency RTK-capable Stonex S5 (S5); L1 frequency Thales MobileMapper Pro (TMMP); low-cost L1 frequency Quanum GPS Logger V2 (QLV2). In order to evaluate the positioning accuracy of these receivers, i.e., the distance of the determined points from a reference trajectory, different tests, distinguished by the use or not of Real-Time Kinematic (RTK) differential correction data and/or an external antenna, were carried out. The results show that all satellite receivers tested carried out with the external antenna had an improvement in positioning accuracy. The Thales MobileMapper Pro satellite receiver showed the worst positioning accuracy. The low-cost Quanum GPS Logger V2 receiver surprisingly showed an average positioning error of only 0.550 m. The positioning accuracy of the above-mentioned receiver was slightly worse than that obtained using Stonex S7-G without the external antenna and differential correction (maximum positioning error 0.749 m). However, this accuracy was even better than that recorded using Stonex S5 without differential correction, both with and without the external antenna (average positioning error of 0.962 m and 1.368 m).

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A Low-Cost, Mobile Real-Time Kinematic Geolocation Service for Engineering and Research Applications

HardwareX ◽

10.1016/j.ohx.2021.e00203 ◽

2021 ◽

pp. e00203

Author(s):

André Broekman ◽

Petrus Johannes Gräbe

Keyword(s):

Real Time ◽

Low Cost ◽

Real Time Kinematic

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Real-time and near real-time ZTD from a local network of low-cost dual-frequency GNSS receivers.

10.5194/egusphere-egu21-5465 ◽

2021 ◽

Author(s):

Tomasz Hadas ◽

Grzegorz Marut ◽

Jan Kapłon ◽

Witold Rohm

Keyword(s):

Water Vapor ◽

Real Time ◽

Low Cost ◽

Weather Prediction ◽

Local Network ◽

System Component ◽

Dual Frequency ◽

Lower Accuracy ◽

Gnss Receivers ◽

The Impact

The dynamics of water vapor distribution in the troposphere, measured with Global Navigation Satellite Systems (GNSS), is a subject of weather research and climate studies. With GNSS, remote sensing of the troposphere in Europe is performed continuously and operationally under the E-GVAP (http://egvap.dmi.dk/) program with more than 2000 permanent stations. These data are one of the assimilation system component of mesoscale weather prediction models (10 km scale) for many nations across Europe. However, advancing precise local forecasts for severe weather requires high resolution models and observing system.&#160; &#160;Further densification of the tracking network, e.g. in urban or mountain areas, will be costly when considering geodetic-grade equipment. However, the rapid development of GNSS-based applications results in a dynamic release of mass-market GNSS receivers. It has been demonstrated that post-processing of GPS-data from a dual-frequency low-cost receiver allows retrieving ZTD with high accuracy. Although low-cost receivers are a promising solution to the problem of densifying GNSS networks for water vapor monitoring, there are still some technological limitations and they require further development and calibration.We have developed a low-cost GNSS station, dedicated to real-time GNSS meteorology, which provides GPS, GLONASS and Galileo dual-frequency observations either in RINEX v3.04 format or via RTCM v3.3 stream, with either Ethernet or GSM data transmission. The first two units are deployed in a close vicinity of permanent station WROC, which belongs to the International GNSS Service (IGS) network. Therefore, we compare results from real-time and near real-time processing of GNSS observations from a low-cost unit with IGS Final products. We also investigate the impact of replacing a standard patch antenna with an inexpensive survey-grade antenna. Finally, we deploy a local network of low-cost receivers in and around the city of Wroclaw, Poland, in order to analyze the dynamics of troposphere delay at a very high spatial resolution.As a measure of accuracy, we use the standard deviation of ZTD differences between estimated ZTD and IGS Final product. For the near real-time mode, that accuracy is 5&#160;mm and 6 mm, for single- (L1) and dual-frequency (L1/L5,E5b) solution, respectively. Lower accuracy of the dual-frequency relative solution we justify by the missing antenna phase center correction model for L5 and E5b frequencies. With the real-time Precise Point Positioning technique, we estimate ZTD with the accuracy of 7.5 &#8211; 8.6 mm. After antenna replacement, the accuracy is improved almost by a factor of 2 (to 4.1 mm), which is close to the 3.1&#160;mm accuracy which we obtain in real-time using data from the WROC station.

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Real-Time Kinematic Precise Orbit Determination for LEO Satellites Using Zero-Differenced Ambiguity Resolution

Remote Sensing ◽

10.3390/rs11232815 ◽

2019 ◽

Vol 11 (23) ◽

pp. 2815 ◽

Cited By ~ 1

Author(s):

Xingxing Li ◽

Jiaqi Wu ◽

Keke Zhang ◽

Xin Li ◽

Yun Xiong ◽

...

Keyword(s):

Real Time ◽

Ambiguity Resolution ◽

Orbit Determination ◽

Precise Orbit Determination ◽

The Real ◽

Precise Orbit ◽

Ambiguity Fixing ◽

Real Time Kinematic ◽

Leo Satellites ◽

Fixed Solution

The rapid growing number of earth observation missions and commercial low-earth-orbit (LEO) constellation plans have provided a strong motivation to get accurate LEO satellite position and velocity information in real time. This paper is devoted to improve the real-time kinematic LEO orbits through fixing the zero-differenced (ZD) ambiguities of onboard Global Navigation Satellite System (GNSS) phase observations. In the proposed method, the real-time uncalibrated phase delays (UPDs) are estimated epoch-by-epoch via a global-distributed network to support the ZD ambiguity resolution (AR) for LEO satellites. By separating the UPDs, the ambiguities of onboard ZD GPS phase measurements recover their integer nature. Then, wide-lane (WL) and narrow-lane (NL) AR are performed epoch-by-epoch and the real-time ambiguity–fixed orbits are thus obtained. To validate the proposed method, a real-time kinematic precise orbit determination (POD), for both Sentinel-3A and Swarm-A satellites, was carried out with ambiguity–fixed and ambiguity–float solutions, respectively. The ambiguity fixing results indicate that, for both Sentinel-3A and Swarm-A, over 90% ZD ambiguities could be properly fixed with the time to first fix (TTFF) around 25–30 min. For the assessment of LEO orbits, the differences with post-processed reduced dynamic orbits and satellite laser ranging (SLR) residuals are investigated. Compared with the ambiguity–float solution, the 3D orbit difference root mean square (RMS) values reduce from 7.15 to 5.23 cm for Sentinel-3A, and from 5.29 to 4.01 cm for Swarm-A with the help of ZD AR. The SLR residuals also show notable improvements for an ambiguity–fixed solution; the standard deviation values of Sentinel-3A and Swarm-A are 4.01 and 2.78 cm, with improvements of over 20% compared with the ambiguity–float solution. In addition, the phase residuals of ambiguity–fixed solution are 0.5–1.0 mm larger than those of the ambiguity–float solution; the possible reason is that the ambiguity fixing separate integer ambiguities from unmodeled errors used to be absorbed in float ambiguities.

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Performance Analysis of the Real Time Kinematic GPS (RTK GPS) Technique in a Highway Project (Stake-Out)

Survey Review ◽

10.1179/003962607x164989 ◽

2007 ◽

Vol 39 (303) ◽

pp. 43-53 ◽

Cited By ~ 10

Author(s):

A. Pirti

Keyword(s):

Performance Analysis ◽

Real Time ◽

The Real ◽

Kinematic Gps ◽

Real Time Kinematic ◽

Gps Rtk ◽

Rtk Gps ◽

Highway Project

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A low cost device for the real-time on-line entry of handprinted characters

Proceedings of the 3rd ACM SIGSMALL symposium and the first SIGPC symposium on Small systems - SIGSMALL '80 ◽

10.1145/800088.802842 ◽

1980 ◽

Author(s):

David D. Thornburg

Keyword(s):

Real Time ◽

Low Cost ◽

The Real ◽

On Line

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Real-Time Dynamic Behavior Evaluation of Active Distribution Networks Leveraging Low-Cost PMUs

Energies ◽

10.3390/en14164999 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4999

Author(s):

Xuejun Zheng ◽

Shaorong Wang ◽

Xin Su ◽

Mengmeng Xiao ◽

Zia Ullah ◽

...

Keyword(s):

Real Time ◽

Dynamic Behavior ◽

Low Cost ◽

Distribution Network ◽

Distribution Networks ◽

Assessment Model ◽

The Real ◽

Time Dynamic ◽

Dynamic Index ◽

Active Distribution Networks

The investigation of real-time dynamic behavior evaluation in the active distribution networks (ADNs) is a challenging task, and it has great importance due to the emerging trend of distributed generations, electric vehicles, and flexible loads integration. The advent of new elements influences the dynamic behavior of the electric distribution networks and increases the assessment complexity. However, the proper implementation of low-cost phasor measurement units (PMUs) together with the development of power system applications offer tremendous benefits. Therefore, this paper proposes a PMU-based multi-dimensional dynamic index approach for real-time dynamic behavior evaluation of ADNs. The proposed evaluation model follows the assessment principles of accuracy, integrity, practicability, and adaptability. Additionally, we introduced low-cost PMUs in the assessment model and implemented them for real-time and high-precision monitoring of dynamic behaviors in the entire distribution network. Finally, a complete model called the real-time dynamic characteristics evaluation system is presented and applied to the ADN. It is pertinent to mention that our proposed evaluation methodology does not rely on the network topology or line parameters of the distribution network since only the phasor measurements of node voltage and line current are involved in the dynamic index system. Thus, the presented methodology is well adaptive to different operation states of ADN despite frequent topology changes. The validation of the proposed approach was verified by conducting simulations on the modified IEEE 123-node distribution network. The obtained results verify the effectiveness and relevance of the proposed model for the real-time dynamic behavior evaluation of ADNs.

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Sliding wire detection system of electric lock screw tool based on motor characteristics

Journal of Physics Conference Series ◽

10.1088/1742-6596/2137/1/012009 ◽

2021 ◽

Vol 2137 (1) ◽

pp. 012009

Author(s):

Ning Zhang ◽

Yinxin Yan ◽

Houcheng Yang ◽

Zhangsi Yu

Keyword(s):

Real Time ◽

Detection System ◽

Low Cost ◽

High Sensitivity ◽

High Accuracy ◽

Normal Operation ◽

Automatic Assembly ◽

The Real ◽

Current Change ◽

Real Time Detection

Abstract This paper presents a sliding wire detection system of electric screw locking tool based on the characteristics of motor. The system can judge whether the screw has sliding wire through the current change of motor during normal operation, and realize the real-time detection and alarm of sliding wire. The system has the advantages of high sensitivity, low cost and high accuracy. It can be widely used in automatic assembly and other fields.

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Estimating Illumination Direction for Augmented Reality in Real-Time by using Low-Cost Sensors

Journal of Computer Science and Technology ◽

10.24215/16666038.17.e20 ◽

2017 ◽

Vol 17 (02) ◽

pp. e20 ◽

Cited By ~ 1

Author(s):

Kevin E. Soulier ◽

Matías Nicolás Selzer ◽

Martín Leonardo Larrea

Keyword(s):

Augmented Reality ◽

Real Time ◽

Low Cost ◽

Time Estimation ◽

The Real ◽

Virtual Objects ◽

Illumination Direction ◽

Real Objects ◽

Real Time Estimation ◽

Commercial Field

In recent years, Augmented Reality has become a very popular topic, both as a research and commercial field. This trend has originated with the use of mobile devices as computational core and display. The appearance of virtual objects and their interaction with the real world is a key element in the success of an Augmented Reality software. A common issue in this type of software is the visual inconsistency between the virtual and real objects due to wrong illumination. Although illumination is a common research topic in Computer Graphics, few studies have been made about real time estimation of illumination direction. In this work we present a low-cost approach to detect the direction of the environment illumination, allowing the illumination of virtual objects according to the real light of the ambient, improving the integration of the scene. Our solution is open-source, based on Arduino hardware and the presented system was developed on Android.

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