Geodetic Technologies Research Articles

EXPERIMENTAL RESEARCH OF THE ACCURACY OF NAVIGATION GNSS - RECEIVERS IN CONDITIONS OF THE CONSTRUCTED TERRITORY

Use of digital geodetic support technologies with the use of GNSS satellite systems in combination with electronic geodetic instruments, introduction of new methods of construction of geodetic networks, collection of information by ground and aerospace surveying, unification of exchange formats of measurement results based on computer technologies and their application conditions. Substantiation and development of remote methods of spatial information collection requires analysis and consideration of a number of errors in order to improve accuracy.
 Wikimapia is a map project for shared use with open content, which aims to identify all geographical objects with the introduction of useful information about them. It combines an interactive web map and a Wiki system.
 One of the features of the Wikimapia resource is that it is possible to determine geographical coordinates. To do this, you need to move the cross cursor on the object of interest and get its coordinates visually.
 The purpose of the study was to determine the accuracy of the coordinates of GPS receivers Garmin Oregon 450 in the built-up area, using as a basis for calibration, the resource "Wikimapia".
 In order to determine the accuracy of the location with the help of GARMIN Oregon 450 GPS receivers, GNSS measurements were performed at 30 marker points.
 Ellipsoidal coordinates were recalculated into spatial rectangles according to known formulas.
 In order to assess the accuracy of determining the location of marker points, the differences in the coordinates of their position were found and the root mean square error from a number of measurements was found.
 The average error of coordinate measurements was ± 4.79 m for the GPS receiver.
 Based on experimental research, the possibility of using the resource "Wikimapia" not only to quickly determine the coordinates of topographic objects, determine their categories, but also with sufficient accuracy to apply for the calibration of navigation GNSS receivers when there is no network of geodetic points.
 A promising direction in the process of scientific and practical research should be the creation of a general mathematical model for predicting the influence of the plurality on the location and improvement of navigation aids.

Geodesic provision for cadastral works: development prospects

The article analyzes the geodesic provision development when performing a cadastral survey. It has been established that improvement will be manifested in the use of modern geodetic technologies - three-dimensional laser scanning. The analysis of literary sources showed that there is a significant number of scientific works on the use of laser scanning for obtaining cadastral data and creating a three-dimensional cadaster. Methods for performing cadastral surveys, criteria for choosing a measuring instrument, methods for assessing the accuracy of coordinates, algorithms for processing the scan data, building models have been developed. However, the issues of further use of three-dimensional information for the cadastral documentation preparation are practically not covered, while the cadastral documentation is the basis for introducing the information into the real estate cadaster. The article presents the results of performing the ground-based laser scanning of a linear object. Additional information that can be introduced to the real estate cadaster in connection with the use of three-dimensional technology - height, technical condition of a linear object has been established. The sections of the technical plan and the changes made to them have been given. In addition, it was revealed that when using three-dimensional data in the preparation of technical plans, it would be inevitable to develop the software that can create boundary, technical plans based on three-dimensional data.

A review of present-day deformation of active volcanoes in China between 1970 and 2013

Abstract China has numerous active volcanoes, and more than 10 erupted in the Quaternary. Although a modern eruption event has not occurred in China, the potential risk from volcanic hazards should be noted. With the development of geodetic technologies including the Global Positioning System (GPS), levelling and interferometric synthetic aperture radar (InSAR), volcanologists can now detect the present-day deformation state of China's active volcanoes. In this paper, we summarize the present-day deformation patterns, magma sources and magma plumbing systems of China's active volcanoes between 1970 and 2013. The results show that the most active volcano in China is the Changbaishan volcano; it showed significant inflation from 2002–03, with the deformation becoming gradually weaker after 2003, indicating that it had been experiencing a magma process during 2000–10. A point source at a depth of c. 10 km was responsible for the observed deformation. The Leiqiong volcanic field showed a trough pattern deformation during 2007–10, which was interpreted as a dyke intrusion model. Fluctuant deformation patterns were shown in the Tengchong volcanic field. The Longgang volcanic field had experienced a volcano-wide uplift during the 1970s and 1990s. Deformation was observed in the Tatun volcanic field from 2006–13, and two shallow sources account for the observed deformation. These volcanoes merit further monitoring given possible evidence of deformation. No obvious deformation related to volcanic activity was observed at the Ashikule volcanic field from 2003–11. The results provide a basic introduction to the deformation state of China's active volcanoes, and may be helpful for evaluating the activity levels of China's volcanoes and mitigating the risks of future volcanic hazards.

Method analysis of surveying of mineral storages in open-pit mining

The final products of mining enterprises are stored in open or closed areas-mineral storages. The duties of the surveyor service include monitoring of the volume of mineral, which is placed in storage. Requirements for the method of shooting and the accuracy of the received results are regulated by normative documents. Taking into account the introduction into production of modern geodetic technology survey of storage can be realized both methods of classical geodesy (the method of perpendiculars, total station survey) and with the use of GPS receivers, scanning laser systems, unmanned aerial vehicles or drones. In the article is given brief characteristic of specified survey methods and possible scope of their use. Based on the characteristic features of the storage: its form and type and taking into account possible method of measurement production (automated, non-automated) was developed method of selecting of survey. So, on the example of the open transshipment ore storage taking into account its form – medium and type – open and predominant use of automated methods of measurement production are survey methods recommended. Based on the results of the calculation of the storage volume was made the conclusion about compliance of received results with requirement of normative documents.

Coordinate support of geographic information space

Today, the transition of mankind to the information society era is becoming an important state problem. Coordinate support of the space around us, timely and high-quality recording of the changes taking place in it, a thorough results’ analysis and reflection is ensured by geodetic technologies, and their innovative development, continuous improvement ultimately contribute to the successful and dynamic development of modern society. However, today we are witnessing contradictions and inconsistencies between the technological geodetic processes and the regulatory documents governing the methodology for performing geodetic work to support various sectors of the economy. To everyone’s surprise, the existing instructions have not been revised since the last century and do not include the use of modern digital technologies for geodetic activities. This methodology should include a global process for the search, collection, storage, processing, including analysis and distribution, and as a result, the information provision concerning the objects and processes to the end user.

Мониторинг литорали с применением беспилотного летательного аппарата

The authors explore the littoral as a natural phenomenon using geodetic methods. Littoral is an areal object and is closely related to coastal abrasion. The abrasion destroys the coastal zone. Preventing the destruction of the coastal zone requires monitoring the littoral, forming its model and that of littoral dynamics. Littoral and dynamo models enable developing recommendations for protecting the coastal zone. Having remote sensing data only we are unable to perform littoral monitoring efficiently. It does not ensure the accuracy and relevance of the state of the coastal zone. The monitoring task can only be solved with the use of integrated geodetic support.This support includes geodetic work and the use of an unmanned aerial vehicle for monitoring the littoral. The authors explore littoral as a natural phenomenon. A new method of obtaining spatial coordinates using images obtained from UAVs is described. The essence of the methodology is determining spatial coordinates using single images. The technology includes the use of water level sensors to define the exact height of the survey. The methodology involves the use of satellite navigation equipment to determine the coordinates of the camera at the time of shooting. Special here is that the littoral boundary is a fuzzy object calculated on the basis of statistical data. The research shows that the geodetic technologies are the basis of the integrated one. The authors providethe analysis of the situation and suggest measures for monitoring the coastline.

A functional-precision analysis of the Vertical Comparator for the Calibration of geodetic Levelling Systems

Abstract Precise geodetic levelling measurements use a measuring set consisting of a precise digital level and digital (bar coded) levelling staffs. Such a measuring set enables automation of height measurement records and obtaining the accuracy of double-run levelling at the level of ±0.2 mm/1 km. Under the existing legislation (international and domestic) levels and levelling staffs should be subject to periodic tests followed by the issuing of calibration certificates. Such tests are carried out with the use of comparators and specialized measuring stations. The paper presents the development and construction of such an instrument, namely the Vertical Comparator for the Calibration of Levelling Systems (hereinafter referred to as VCCLS) in the Laboratory of Geodetic Technologies (LGT) of the Wroclaw University of Environmental and Life Sciences (Pol. Uniwersytet Przyrodniczy we Wroclawiu; hereinafter: UPWr). Presented and discussed in the paper are experimental and research works concerning the construction and functionality of the comparator as well as the environment conditions in the LGT. An analysis of the results of testing of two levelling systems: of Leica and Trimble companies allowed for defining the extended uncertainty of the comparator (at the confidence level of 95%), which amounted to ±2.1 μm. The paper demonstrates the advantages of the original Vertical Comparator for the Calibration of geodetic Levelling Systems as compared to design solutions known from the professional literature. Designed and constructed at UPWr, the novel VCCLS is characterized by uncomplicated construction, simple adjustment of its interferometric measuring system and versatility as it can be used to test digital geodetic levelling systems which apply both digital and analog levelling staffs of different manufacturers (including Leica, Trimble, Topcon, Sokkia, Zeiss).

Geodesy and modern technologies

Currently, a lot of geodetic instruments and new geodetic technologies have been created, which are fundamentally different from traditional ones. In previous years, each type of measurement had its own type of instrument: for the angular measurements, the theodolite, for high-altitude measurements - a level, for linear measurements - a tape measure and rangefinder. Each device, depending on the intended use, had its own accuracy characteristics. Over time, science is developing and technologies are moving forward, the devices used in the field of engineering and geodetic works are improving. A modern geodetic instrument is a product of new technologies that embodies the latest achievements in optics and modern satellite technologies. This article provides a classification of devices according to their purpose and describes their application.

RESEARCH AND IMPLEMENTATION OF GEODETIC DATABASE SYSTEM

Abstract. With the gradual formation of the space technical system of National Geodetic Datum, the storage management and application services of the geodetic data have been developing rapidly. This paper studies Geodetic data content, characteristics, classification principles and classification methods in the geodetic technology system and initially forms a standard classification system of geodetic data. On the basis of studying the key technical links to the modern Geodetic Datum comprehensive data acquisition, storage, management and service, this paper has tackled the real-time data optimal storage based on DBFS technology. Technical problems such as multi-dimensional data integration and docking of the software, building a safe and standardized management and the geodetic data service system, coordinating the application of network resources, storage resources, computing resources and other soft and hard environment elements, achieving efficient management and service of land, sea and air integrated observation data results, greatly improving the management ability and application service level of Geodetic data, for surveying and mapping. Business operation of the benchmark database provides support and promotes the social application on geodetic results.

Evaluation of Factors, Influencing the Accuracy of the Digital Model, Obtained by Laser Scanning

Measurements in terrestrial laser scanning (TLS) are not perfect and are subject to errors caused by various factors affecting the quality of the capture process and the resulting final product. Careful consideration of all these factors and errors provides a good basis for assessing the quality of the data and the information received. The accuracy of the 3D model obtained from laser scanning is influenced by the density of the measurements and the modelling methods. 3D modelling algorithms allow accuracy to be improved, but modelling software cannot solve all the problems, and it is impossible to achieve high quality 3D modelling without taking into account the factors that affect the accuracy of the measurements. The investigation of error sources in TLS measurements is rather complicated due to the large number of influencing factors that are interconnected. In addition to angular and longitudinal measurements, most scanning systems also offer a measure of the intensity of the reflected signal. Because the TLS is a non-reflective geodetic technology, it means that the measurement results are highly dependent on the reflectivity of the materials. The energy of the reflected signal depends on the following physical factors: object material properties, surface colour of the object, surface temperature, surface humidity, illumination. From the experimental studies it has been confirmed that the illumination and humidity of the scanned surfaces have a significant impact on their reflecting ability and the density of the received point cloud. Evaluation of digital model accuracy is made with a plane approximation and comparison with control points. Areas with different point densities were created in order to analyse the accuracy of 3D model and to determine the optimum scanning density.

EXPERIENCE OF USING GLS-1500 SCANNER IN ENGINEERING-GEODETIC SURVEYING OF ROADS

Abstract: modern geodetic technologies allow us to quickly obtain relevant, precise and reliable geospatial data. An example of such a technology is ground-based laser scanning. Currently, this technology is actively used in the performance of engineering and geodetic surveys of roads. The devices and software of different companies are used, differing in their accuracy characteristics and functionality. The article focuses on the experience of the use of GLS-1500 ground-based laser scanner produced by TOPCON and ScanMaster ground-based laser scanning data processing software for engineering and geodetic surveys in order to repair nine sections of the Federal highway R-256 "Chuysky tract" with a total length of over than 100 km. The article also describes the options used for registration of scanning data, the features of their use depending on the availability of geodetic control on the object. The order of processing the results of ground-based laser scanning using ScanMaster software is considered. According to the results of field work on ground-based laser scanning of nine sections of the R-256 highway, the time and accuracy of scanning data were estimated. The method of estimation of time spent on scanning works is also described. The issue of evaluating the accuracy of obtaining the scan data in the ScanMaster software is considered. It is noted that the accuracy of the geodetic reference, thus, the accuracy of the absolute orientation of the scans can be estimated by the differences between the coordinates of the marks that were scanned from the location of the device and calculated by ScanMaster software, and their specified values obtained from the equalization of the geodetic control. In conclusion, it is stated that the optimal time and accuracy of scanning with GLS-1500 device are achieved by using the geodetic reference of the scans by the inverse length-angle intersection at two points of the geodetic control.

Time Series of Land subsidence rate on Coastal Demak Using GNSS CORS UDIP and DINSAR

Most of the studies land subsidence and impact have been done on the north coastal area of Java, especially Semarang and Demak. This landsubsidence has a very serious impact both in the infra structure, the economy and the environment. Techniques of observing landsubsidence using geodetic methods have been widely practiced. Geodetic technology is undergoing rapid development, especially in GNSS navigation satellite technology as well as satellite radar interferometry. Both have advantages and disadvantages of each. In this study will examine the application of DinSAR interferometric techniques and GNSS technology to predict the rate of land subsidence coastal of Demak regency. This paper also emphasize the role of GNSS and DinSAR application in deformation especially for landsubsidence monitoring.

Application of the Takaga-Sugeno neuro-fuzzy model for determining of engineering structures

The objective of the paper is to show the role of geodetic monitoring and modern methods of measurement data processing with the use of neural-fuzzy systems in identifying changes occurring in engineering structures. Fast methods of measurement and data processing are of key importance whenever rapidly changing phenomena should be captured (e.g. deformations of buildings, fires spreading in forest areas, flood waves, landslides caused by endogenous and exogeonic factors). Processes and phenomena occurring in engineering structures can be modelled based on information obtained by geodetic monitoring. At present, elements of geodetic technologies are being supplemented with artificial intelligence methods, which include neuro-fuzzy systems. These systems can process information that is provided at the input both as numerical and linguistic values. This approach is used for qualitative assessment of the condition of objects and physical quantities and it is characterized by parallel information processing. The paper presents the possibility of using the Takaga-Sugeno neural-fuzzy model for prediction and assessment of horizontal and vertical displacements of engineering structures as illustrated by the example of a historical footbridge in Muskauer Park, located in Germany and Poland.

CONSTRUCTION OF FRAME GEODETIC NETWORK FOR ENGINEERING SURVEY OF RAIL TRANSPORT FACILITIES

Increasing the speed of trains along railroad tracks and the development of satellite geodetic technologies put forward new requirements for the production of the engineering survey at the rail transport facilities. Ensuring the safety of high-speed traffic is directly related to the accuracy of determining the coordinates and heights of the reference geodetic networks created for the design, construction, reconstruction and operation of railways. A large length of Railways in Russia requires solving a number of problems in the conditions of increasing the accuracy of determining the coordinates. High-speed route crosses several regions with its own local coordinate systems. Simplify the design and cadastral works and reduce to minimum linear distortions when performing geodetic measurements, allows the creation of a local coordinate system, unified for the entire route. The technology of creating a unified local coordinate system for linear objects passing through several 6-degree zones in the projection of GaussKruger and objects located at an angle to the axial Meridian is considered on the example of the railway Moscow — Saint-Petersburg — Vyborg. At the basis of a unified local system of the object, it is proposed to use an oblique cylindrical cartographic projection. Implemented a coordinate system in the form of the software, allowing to perform transformations between the local system, the world and state coordinate systems. The paper also considers the practical experience of creating a high-precision geodetic reference network for a high-speed railway traffic route, which can be used for various linear engineering structures. The created frame network can serve as a geodetic base for performing laser scanning, monitoring facilities, creating geoinformation systems and solving other problems that arise during the operation of an engineering facility.

Study of Soligorsk Salt Tailings Piles while Using Up-To-Date Geodetic Technologies

. Intensive development of the Starobinsk deposit is related with formation of salt tailings piles which are annually increasing and they have already reached the height of 120–150 m, their volume constitutes 1.5 billion tons and their area is equal up to »3000 ha. Such situation leads to activation of geodynamic processes, salting of soil and underground water. For this reason study of salt tailings piles with the help of up-to-date geodetic technologies is considered as the most efficient methods for environmental protection. Geodetic innovation technologies for study of salt tailings relief include the following: creation of plan and height control along relief perimeter and route of equipment motion within salt tailings pile with the help GPS-system; experimental study of salt tailings relief while using an electronic tacheometer with reflectorless regime; import of total station coordinates in software package LISCAD Plus where simulation of salt tailings is formed; study of digital salt tailings simulation and its interpretation. More accurate study of salt tailings is carried out by laser scanning while using scanner Leica ScanStation C10. Operations from several stations are executed with the purpose to obtain data on salt tailings and these operations provide their complete survey. Results of the survey are loaded into a computer; the data is compiled together and so a digital simulation of salt tailings is obtained. An advantage of laser scanning is complete automation and due to this accuracy is increased significantly and time required for the survey is reduced. Such approach makes it possible to increase efficiency in various measures directed on improvement of environmental conditions.

Monitoring of Buituri Slag Dump, Hunedoara County in Relation with Environmental Protection

Detailed analysis of appearance and relief evolution in mining areas cannot be done without mining engineering concepts. Over time, researchers around the world have responsibly been involved in this matter necessary for the development of society, also with obvious implications and repercussions over the quality of life. The purpose of the scientific research detailed in this paper comprises in monitoring the slag dump from Buituri, Hunedoara County using space geodetic technology. Slag dump is the result of steel production activities carried out under the steel factory Arcelor Mittal Hunedoara S.A., formerly known as the steel factory Hunedoara - Siderurgica S.A. Therefore it was decided to conduct monthly topographic measurements to monitor possible dynamic changes that may appear in the context of continuous exploitation of the above mentioned slag dump. Monitoring possible movements is performed by comparing transversal and longitudinal profiles drawn based on zero measurement carried out on 20.05.2011, with the ones obtained after processing of the monthly measurements realized throughout the years 2011, 2012, 2013, 2014, 2015 and 2016. Also, for observing the displacements, comparative charts or tables with records regarding coordinates differences are studied. The issue of measuring and graphic representation of settlements, horizontal linear movements and landslides for structures such as slag or sterile dumps, requires further studies and interdisciplinary research, creating links between specialists in the fields of terrestrial measurements science and geology.

A Cost-Effective Geodetic Strainmeter Based on Dual Coaxial Cable Bragg Gratings.

Observations of surface deformation are essential for understanding a wide range of geophysical problems, including earthquakes, volcanoes, landslides, and glaciers. Current geodetic technologies, such as global positioning system (GPS), interferometric synthetic aperture radar (InSAR), borehole and laser strainmeters, are costly and limited in their temporal or spatial resolutions. Here we present a new type of strainmeters based on the coaxial cable Bragg grating (CCBG) sensing technology that provides cost-effective strain measurements. Two CCBGs are introduced into the geodetic strainmeter: one serves as a sensor to measure the strain applied on it, and the other acts as a reference to detect environmental noises. By integrating the sensor and reference signals in a mixer, the environmental noises are minimized and a lower mixed frequency is obtained. The lower mixed frequency allows for measurements to be taken with a portable spectrum analyzer, rather than an expensive spectrum analyzer or a vector network analyzer (VNA). Analysis of laboratory experiments shows that the strain can be measured by the CCBG sensor, and the portable spectrum analyzer can make measurements with the accuracy similar to the expensive spectrum analyzer, whose relative error to the spectrum analyzer R3272 is less than ±0.4%. The outputs of the geodetic strainmeter show a linear relationship with the strains that the CCBG sensor experienced. The measured sensitivity of the geodetic strainmeter is about −0.082 kHz/με; it can cover a large dynamic measuring range up to 2%, and its nonlinear errors can be less than 5.3%.

Enabling innovation through geodetic technologies: a provincial perspective

Geodetic technologies enable the measurement of the size, shape and orientation of the Earth, as well as the variation of these parameters over time. Advances in geodetic technology over the past few decades, particularly relating to Global Navigation Satellite Systems (GNSS), have made access to real-time centimetre-level positioning accuracy commonplace. As spatial position information becomes more critical to human and artificial intelligence decision-making processes, innovation has ensued to leverage that information. A review of key advances in geodetic technology is provided. Examples of innovations that leverage these technologies are presented. It is concluded that the role of geodetic infrastructure will become increasingly important as the backbone for other innovations and that jurisdictions investing resources in this area will be more likely to realize the potential economic benefits and operational efficiencies it creates.

Transient deformation in the Asal‐Ghoubbet Rift (Djibouti) since the 1978 diking event: Is deformation controlled by magma supply rates?

AbstractThe Asal‐Ghoubbet Rift (AG Rift) in Djibouti lies in the subaerial continuation of the Aden ridge system, thereby constituting a unique location to study rifting processes and mechanisms involved in continental breakup and oceanic spreading. Continually upgraded and expanded geodetic technology has been used to record the 1978 Asal rifting event and postdiking deformation. In light of recent results obtained for the Manda Hararo‐Dabbahu rifting event (2005–2010), we propose that the horizontal and vertical geodetic data can be modeled with a double source, involving a dike‐like inflation component aligned along the rift axis and a spherical pressure source located at midsegment below the Fieale caldera. By revisiting the codiking data, we propose that the reservoir below Fieale could have fed, at least partially, the 1978 injection and the contemporaneous Ardoukôba eruption and potentially induced local subsidence due to magma draining out of the central reservoir. As an alternative to previously proposed viscoelastic relaxation models, we reinterpret postdiking observations using a purely elastic rheology. We determine the relative contribution of a midsegment reservoir inflation and a dike‐like opening component, together with their respective time evolutions. Our results suggest that interactions between steadily accumulating tectonic strain and temporal variations in melt supply to the shallow magma plumbing system below the AG Rift may entirely explain the geodetic observations and that viscoelastic deformation processes played a minor role in the 30 years following the 1978 rifting event.

RPAS ACCURACY TESTING FOR USING IT IN THE CADASTRE OF REAL ESTATES OF THE CZECH REPUBLIC

In the last few years, interest in the collection of data using remotely piloted aircraft systems (RPAS) has sharply risen. RPAS technology has a very wide area of use; one of its main advantages is its accuracy, timeliness of data, frequency of collecting data and low operating costs. RPAS can be used for the mapping of small, dangerous and inaccessible areas in contrast with ordinary aerial photogrammetry. In the cadastre of real estates of the Czech Republic, it is possible to map out areas by using aerial photogrammetry, so it has been done in the past. However, this is a relatively expensive and complex technology, and therefore we are looking for new alternatives. An alternative would be to use RPAS technology for data acquisition. The testing of the possibility of using RPAS for the cadastre of real estates of the Czech Republic is the subject of this paper. When evaluating results we compared point coordinates measured by geodetic method, GNSS technology and RPAS technology.