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Greiwe A.,Civil Engineering and Geomatics | Gehrke R.,Civil Engineering and Geomatics | Spreckels V.,RAG Aktiengesellschaft | Schlienkamp A.,RAG Aktiengesellschaft
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2013

Since a few years, micro UAS (unmanned aerial systems) with vertical take off and landing capabilities like quadro- or octocopter are used as sensor platform for Aerophotogrammetry. Since the restricted payload of micro UAS with a total weight up of 5 kg (payload only up to 1.5 kg), these systems are often equipped with small format cameras. These cameras can be classified as amateur cameras and it is often the case, that these systems do not meet the requirements of a geometric stable camera for photogrammetric measurement purposes. However, once equipped with a suitable camera system, an UAS is an interesting alternative to expensive manned flights for small areas. The operating flight height of the above described UAS is about 50 up to 150 meters above ground level. This low flight height lead on the one hand to a very high spatial resolution of the aerial imagery. Depending on the cameras focal length and the sensor's pixel size, the ground sampling distance (GSD) is usually about 1 up to 5 cm. This high resolution is useful especially for the automatic generation of homologous tie-points, which are a precondition for the image alignment (bundle block adjustment). On the other hand, the image scale depends on the object's height and the UAV operating height. Objects like mine heaps or construction sites show high variations of the object's height. As a result, operating the UAS with a constant flying height will lead to high variations in the image scale. For some processing approaches this will lead to problems e.g. the automatic tie-point generation in stereo image pairs. As precondition to all DEM generating approaches, first of all a geometric stable camera, sharp images are essentially. Well known calibration parameters are necessary for the bundle adjustment, to control the exterior orientations. It can be shown, that a simultaneous on site camera calibration may lead to misaligned aerial images. Also, the success rate of an automatic tie-point generation differs extremely between several photogrammetric software packages. In this article, the calibration results of a suitable camera system will be shown. For a small format consumer grade camera, the authors will give the proof of ability for photogrammetric measurements purposes. This includes the results of different processing approaches for DEM generation of environments showing high object height variations.


Reulke R.,Humboldt University of Berlin | Baltrusch S.,Amt fur Geoinformation | Brunn A.,RapidEye AG | Komp K.,EFTAS Remote Sensing Transfer of Technology | And 3 more authors.
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2012

10 years after the first introduction of a digital airborne mapping camera in the ISPRS conference 2000 in Amsterdam, several digital cameras are now available. They are well established in the market and have replaced the analogue camera. A general improvement in image quality accompanied the digital camera development. The signal-to-noise ratio and the dynamic range are significantly better than with the analogue cameras. In addition, digital cameras can be spectrally and radiometrically calibrated. The use of these cameras required a rethinking in many places though. New data products were introduced. In the recent years, some activities took place that should lead to a better understanding of the cameras and the data produced by these cameras. Several projects, like the projects of the German Society for Photogrammetry, Remote Sensing and Geoinformation (DGPF) or EuroSDR (European Spatial Data Research), were conducted to test and compare the performance of the different cameras. In this paper the current DIN (Deutsches Institut fuer Normung - German Institute for Standardization) standards will be presented. These include the standard for digital cameras, the standard for ortho rectification, the standard for classification, and the standard for pan-sharpening. In addition, standards for the derivation of elevation models, the use of Radar/SAR, and image quality are in preparation. The OGC has indicated its interest in participating that development. The OGC has already published specifications in the field of photogrammetry and remote sensing. One goal of joint future work could be to merge these formerly independent developments and the joint development of a suite of implementation specifications for photogrammetry and remote sensing. © 2012 ISPRS.


Wegmuller U.,Gamma Remote Sensing AG | Walter D.,Clausthal University of Technology | Spreckels V.,RAG Aktiengesellschaft | Werner C.L.,Gamma Remote Sensing AG
IEEE Transactions on Geoscience and Remote Sensing | Year: 2010

In the past, the application of Persistent Scatterer Interferometry (PSI) was primarily possible in the case of slow (less than a few centimeters per year) uniform movements. In this paper, we show how PSI permits the monitoring of relatively fast (including rates up to > 50cm/year) and nonuniform movements using TerraSAR-X repeat observations over deep-level mining. To enable this, parts of the PSI methodology were adapted to the special characteristics of the example studied. Apart from a description of the methodology used and the result achieved, error considerations and a validation of the result with in situ measurements are included. © 2009 IEEE.


Skirde J.,RAG Aktiengesellschaft | Haasler D.,RAG Aktiengesellschaft | Kipp R.,RAG Mining Solutions GmbH
Mining Report | Year: 2013

With the directives 2008/43/EC and 2012/4/EU, the EU has laid down that all commercially used explosives have to be marked with electronically readable labels from 5 April 2013 at the latest. Manufacturers are required to deliver their products with bar codes and provide the customer a listing of the products supplied in electronic form. The customer, that is the user of the explosives, is required from April 2015 to keep records of each individual item in electronic form. The SAP program "Electronic Explosives Registry" (EXR) has already been in use at the RAG AG since April 2013. With this SAP program, it is possible to carry out the legally required stock control of explosives, detonating cords and detonators for each individual part number. The program is an integrated part of the SAP module MM. All material movements are recorded in the program, enabling identification of each item through its life cycle. © 2013 Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.


Spreckels V.,RAG Aktiengesellschaft | Syrek L.,RAG Aktiengesellschaft | Schlienkamp A.,RAG Aktiengesellschaft
Photogrammetrie, Fernerkundung, Geoinformation | Year: 2010

This paper is a part of the DGPF project "Evaluation of Digital Photogrammetric Camera Systems" and encloses the analyses of the working group "Stereoplotting". The digital imagery of the analogue camera Zeiss RMK Top 15, the digital large format frame cameras Vexcel Imaging Ultra-CamX and Intergraph/ZI DMC and the combination of four mid-format cameras Quattro DigiCAM from IGI have been used for stereoplotting. The individual point measurement accuracy has been determined for all cameras and ground sampling distances. The stereo-photogrammetric measurements for ground control points and for topographic point and line measurements have been compared between the cameras and to the terrestrial ground control point coordinates. The aerial flight campaigns are strongly influenced by the current weather conditions at the flying time. For this reason an - as far as possible - impartial evaluation could only be given by the comparison of the individual point measurement accuracy or identical point measurements in the mapping results of different aerial campaigns. © 2010 E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany.


A face equipment for mechanical extraction in longwall mining, in particular in the underground hard coal mining industry, includes a face conveyor (17) arranged along the mining wall, an extraction device (18) that can be moved along the face conveyor (17), and shield support frames (10) supported on the face conveyor (17) at an angle thereto. In order to determine the height of the face opening, a flexible hose level (21) with a liquid-filled hose (22) placed between the face conveyor (17) and at least one main component of the shield support frame (10) is installed in the area of the face conveyor (17). A pressure sensor (23, 24, 28) is arranged on at least one end of the hose (22). An inclination measuring device (25, 26) is arranged on the face conveyor (17) and on the main component of the shield support frame (10).


A face equipment for mechanical extraction in longwall mining, in particular in the underground hard coal mining industry, includes a face conveyor (21) arranged along the coal face, an extraction mechanism (22) that can be moved along the face conveyor (21), and shield support frames (10) fastened at an angle to the face conveyor (21). In order determine the shield height of the extended shield support frame (10) corresponding to the face opening height, a flexible hose level (17) with a liquid-filled hose (18) is installed between the roof canopy (13) and floor skid (11) of individual shield support frames (10), and a pressure sensor (19) is arranged on the skid-side end of the hose (18). An inclination measuring device (25) is arranged on the roof canopy (13), and the pressure sensor (19) and inclination measuring device (25) are connected to an analyzing and control unit.

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