Choosing a camera for mine surveying of mining enterprise facilities using unmanned aerial vehicles

Purpose. Choosing an effective method for performing the mine surveying of the objects at mining enterprise based on the implementation of practical and analytical work. Particular attention is focused on the use of modern technologies for performing field and cameral work, which, in turn, enable to determine the most effective tools and methods for per-forming survey work in open pits, dumps, in collapse zones, and the like. At the same time, one of the priorities when creating graphic material in the form of a mine surveying plan or other mining-graphic documentation is strict compliance with the requirements for the quality of the drawn up documents. Methods. Analysis of the experimental data obtained as a result of the survey work: the mine territory, where the earth’s surface collapsed; open pit flank where displacement is observed; open pit area, where reclamation is conducted. The photographic survey from the ground and from the air is made with digital cameras with different specifications for matrices and lenses. When surveying from the ground, photography from a tripod is used, and when surveying from the air, the camera is carried by an unmanned aerial vehicle. Findings. The qualitative characteristics of the images have been obtained, created by different cameras in various photographic survey conditions. The dependence of the accuracy in determining the points coordinates from the digital images on the quality characteristics of the survey equipment has been obtained, which is used when photographing from the ground or installed on unmanned aerial vehicle. Originality. Patterns have been obtained between the accuracy of the data, measured from the research object images, and the metric characteristics of digital cameras and lenses that are used to obtain them. Practical implications. A method has been developed for performing highly efficient photographic surveys of open pits, dumps and other facilities of mining enterprises. Practical data have been obtained and analysed for the use of various types of cameras and lenses to them. The analysis of the measurement characteristics of the images makes it possible to conclude that further research in this direction is necessary in order to improve the existing methods for performing ground and air photography of open pits and other objects of mining enterprises.Мета. Вибір ефективного методу виконання маркшейдерської зйомки об’єктів гірничодобувних підприємств на основі використання сучасних технологій для виконання польових і камеральних робіт на кар’єрах, відвалах, ділянках зон обвалень тощо. Одним із пріоритетів при створенні графічного матеріалу у вигляді маркшейдерського плану або іншої гірничо-графічної документації є суворе дотримання вимог, які пред’являються до якості документів, що складаються. Методика. Аналіз експериментальних даних, отриманих у результаті виконаних знімальних робіт: території шахти, де відбулося обвалення земної поверхні; борту кар’єру, де спостерігається зсув; території кар’єру, де проводиться рекультивація. Зйомки з землі та з повітря виконані цифровими камерами з різними технічними характеристиками матриць і об’єктивів. При зйомці з землі використовувалося фотографування зі штатива, а при зйомці з повітря носієм камери був безпілотний літальний апарат (БПЛА). Результати. Отримані якісні характеристики зображень, які були створені різними камерами в різних знімальних умовах. Дослідження показали, що при зйомці з відстані 600-700 м від об’єкта, істотної різниці між зображеннями, отриманими 18-ти й 24-мегапіксельними камерами, немає. Це стосується й камер, які встановлюються на дронах. Отримана залежність точності визначення координат точок по цифрових знімках від якісних характеристик знімальної апаратури, яка використовується при фотографуванні з землі або встановлюється на БПЛА. Наукова новизна. Виявлено взаємозв’язок між точністю обмірюваних даних по знімках, отриманих для досліджуваного об’єкта, і метричними характеристиками цифрових камер та об’єктивів, які використовувалися для їх одержання. Практична значимість. Розроблена методика виконання зйомок кар’єрів, відвалів та інших об’єктів гірничорудних підприємств із найбільшою їх ефективністю, що є корисним у гірництві для проектування, моніторингу та прогнозування. Рекомендується подальші дослідження вести у напрямку вдосконалення існуючих на сьогодні методів виконання наземного й повітряного фотографування кар’єрів та інших об’єктів гірничорудних підприємств.Цель. Выбор эффективного метода выполнения маркшейдерской съемки горнодобывающих предприятий на основе использования современных технологий для выполнения полевых и камеральных работ на карьерах, отвалах, участках зон обрушений и тому подобное. Одним из приоритетов при создании графического материала в виде маркшейдерского плана или другой горно-графической документации является строгое соблюдение требований, предъявляемых к качеству составляемых документов. Методика. Анализ экспериментальных данных, полученных в результате выполненных съемочных работ: территории шахты, где произошло обрушение земной поверхности; борта карьера, где наблюдается смещение; территории карьера, где проводится рекультивация. Съемки с земли и с воздуха выполнены цифровыми камерами с различными техническими характеристиками матриц и объективов. При съемке с земли использовалось фотографирование со штатива, а при съемке с воздуха носителем камеры был беспилотный летательный аппарат (БПЛА). Результаты. Полученные качественные характеристики изображений, которые были созданы различными камерами в различных съемочных условиях. Исследования показали, что при съемке с расстояния 600-700 м от объекта, существенной разницы между изображениями, полученными 18-ти и 24-мегапиксельными камерами, нет. Это касается и камер, которые устанавливаются на дронах. Полученная зависимость точности определения координат точек по цифровым снимкам от качественных характеристик съемочной аппаратуры, которая используется при фотографировании с земли или устанавливается на БПЛА. Научная новизна. Выявлена взаимосвязь между точностью измеренных данных по снимкам, полученным для исследуемого объекта, и метрическими характеристиками цифровых камер и объективов, которые использовались для их получения. Практическая значимость. Разработана методика выполнения съемок карьеров, отвалов и других объектов горнорудных предприятий с наибольшей их эффективностью, что является полезным в горном деле для проектирования, мониторинга и прогнозирования. Рекомендуется дальнейшие исследования вести в направлении совершенствования существующих на сегодня методов выполнения наземного и воздушного фотографирования карьеров и других объектов горнорудных предприятий.The authors express their gratitude to the PJSC “Central Iron Ore Enrichment Works” administration for the provided opportunity to conduct research at its facilities

The study of the collapse zone by remote methods

The aim of the research is to choose an effective remote method for surveying the area located above the space mined by underground mining. Often in separate sections of these territories funnels and dips are formed that do not allow the use of methods with finding the performer directly at these potentially dangerous sites. The research methodology is based on the implementation of survey work in the territory of the Ordzhonikidze mine, where underground mining is influencing the state of the ground surface and buildings. In this case, various remote survey methods were used. An analysis of the results of the survey work made it possible to determine the most effective method for studying dangerous areas in which horizontal and vertical deformations are observed. As a result of research, special attention was paid to the use of modern remote sensing methods for the territory of the mine. As a result of the analysis of the survey using remote methods, the expediency of applying the method of terrestrial stereo survey is determined, which has the necessary accuracy, and at the same time it is quite operational. The scientific novelty of the obtained results lies in the fact that the effectiveness of the use of ground-based digital stereo survey for studying the deformations of the ground surface and objects located in the mine and adjacent areas that are undermined by underground mining has been proved. The optimal conditions for performing stereo survey of the ground surface and objects of these territories are determined, and a scheme for performing the binding of survey stations is selected. The practical significance of the research is to study the deformations of the ground surface and buildings on the mine territory and adjacent areas, terrestrial digital stereo survey was used, which made it possible to quickly determine horizontal and vertical deformations for a large number of points with the necessary accuracy

Digital survey in studying open pit wall deformations

The article highlights the topical problem of increasing efficiency of survey during monitoring of rock and earth surface displacement when studying various kinds of deformations caused by mining. To settle the problem, new methods based on use of new devices, programmes and technologies are applied along with traditional ones. The object of the study is an open-pit slide. As it is dangerous to stay on, remote monitoring methods become the most efficient ones, digital photogrammetric survey being one of them. Digital survey methods are being improved along with development of more sophisticated devices and software. The article deals with the method of open-pit slide monitoring involving digital ground survey with the Canon EOS1200D camera. Camera station reference was performed on the basis of GPS data and marker reference – by intersections

Research into harmful effect of underground mining operations on the state of buildings and structures located in the displacement area

An urgent task of both the mine surveyor service and the entire mining sector is to develop and implement in production the remote digital methods for monitoring the deformations of buildings and structures, which are located in areas influenced by underground mining operations. When developing a new methodology for determining the buildings and structures deformations, special attention is paid to improving the photogrammetric method. The study is aimed at determining the optimal conditions for digital imaging of buildings and structures in order to obtain the deformation values with the required accuracy. Based on the results of experimental work on the simultaneous different-scale images processing, the accuracy of determining the planimetric coordinates and heights of the studied points is much higher compared to the previously used methodology, in which digital models of an object are plotted from images obtained by a single camera lens, that is, with the same metric characteristics. The use of high degree of detail and fragmentation of large-scale images, as well as a significantly smaller number of small-scale images, covering the surveyed object, improve the accuracy of determining the position of points, which in turn affects the reduction of the error in combining the models

The use of the construction with a digital camera and GPS receiver while researching dangerous areas

The purpose of the study is to select an effective methods and equipment for observing deformations in dangerous areas of the terrain, such as areas that are undermined by underground mining. It is known that the topical task of the mine surveying service is to improve remote sensing methods for the state of movement zones with craters, dips, cracks. The research methodology is based on the results of the performed analysis of methods for observing deformations using modern devices and technologies, and experimental work using the developed methodology, which provides for the combined use of digital methods and GPS technologies. Experimental work was carried out at the facilities of the Ordzhonikidze mine using various remote sensing methods, including those developed by the authors. The research used a design consisting of a digital camera and a GPS receiver. The performed analysis of the obtained survey results, using the proposed design of two devices, has shown its effectiveness in remote methods of observing the objects deformations located in areas undermined by mining operations. The scientific novelty of the results obtained lies in the methods development for remote observation of deformations of the ground's surface and objects, based on the structure use from a digital camera and a GPS receiver. This method was developed to increase the efficiency of performing research on objects deformations located in places that are dangerous for finding a person. The efficiency of using terrestrial digital stereo survey when the coordinates of the photographing points are determined with the help of GPS has been proved. The practical significance of the study lies in increasing work efficiency the on monitoring deformations of the earth's surface, buildings and structures located in areas dangerous for field work by traditional methods, which are performed using leveling and measuring the distances between the benchmarks of profile lines, which are usually used on areas undermined by underground mining. The use of terrestrial digital stereo photography with the coordination of photographing stations using GPS allows remote determination of the spatial position of the observed points with the required accuracy. Key words: ground stereoscopic survey, collapse zone, digital camera, GPS

Development of resource-saving technology when mining ore bodies by blocks under rock pressure

The article aims to develop the resource-saving technology when mining steep ore bodies applying 250 mm-diameter boreholes to break ore into the compressed environment. This will reduce dilution of the mined ore mass in conditions of rock pressure around blocks. When mining iron ore deposits of Kryvyi Rih basin, applied mining systems allow for creation of the compensatory space as the first stage. However, these stopes fail under rock pressure, this influencing negatively ore breaking and extraction. The degree of extraction can be increased through breaking ore mass into the compressed environment. The width of the ore layer to be broken onto the compressed environment is determined through industrial investigations. To enhance breaking conditions, it is suggested to apply boreholes of a larger diameter. However, there is no technique developed for determining thickness of the ore layer to be broken depending on the borehole diameter and the fragmentation factor. When applying 250 mm boreholes, increase of thickness of the layer to be broken from 2 to 10 m is found to cause compaction of the previously broken layer up to 3 m with the optimal ore fragmentation factor of 1.3–1.5 and 3-fold decrease of lumps yield. This results from the fact that drilling a 250 mm borehole to secure even provision of the massif with explosives reduces the line of the least resistance