bluuebunny/crossref_metadata_2025 huggingface dataset:
GEOMETRIC PROPERTIES OF A MECHANICAL FORWARD MOTION COMPENSATION SYSTEM CONTROLLED BY A PIEZOELECTRIC DRIVE
Authors: Collette F. , Gline S. , Losseau J. , Lecharlier L.
Published: August 2012

Abstract. Forward Motion Compensation (FMC) systems have been designed to ensure the radiometric quality of motion acquisition in airborne cameras. If the radiometric benefits of FMC have been acknowledged, what are its effects on the geometrical properties of the camera? This paper demonstrates that FMC significantly improves geometrical properties of a camera. Aspects of FMC theory are discussed, with a focus on the near-lossless implementation of this technology into digital aerial camera systems. Among mechanical FMC technologies, the piezoelectric drive is proving to excel in dynamic positioning in both accuracy and repeatability. The patented piezoelectric drive integrated into Optech aerial camera systems allows for continuous and precise sensor motion to ensure exact compensation of the aircraft's forward motion. This paper presents findings that demonstrate the validity of this assertion. The paper also discusses the physical principles involved in motion acquisition. Equations are included that define the motion effect at image level and illustrate how FMC acts to prevent motion effects. The residual motion effect or compensation error is formulated and a practical computation applied to the more restrictive camera case. The assessment concludes that, in the range of airborne camera utilization, the mechanical FMC technique is free of "visible" error at both human eye and computer assessment level. Lastly, the paper proceeds to a detailed technical discussion of piezoelectric drives and why they have proven to be so effective as nanopositioning devices for optical applications. The effectiveness of the patented piezoelectric drives used to achieve FMC in Optech cameras is conclusively demonstrated.
ROBUST PERSON TRACKING WITH MULTIPLE NON-OVERLAPPING CAMERAS IN AN OUTDOOR ENVIRONMENT
Authors: Hellwig S. , Treutner N.
Published: August 2012

Abstract. The aim of our work is to combine multiple cameras for a robust tracking of persons in an outdoor environment. Although surveillance is a well established field, many algorithms apply various constraints like overlapping fields of view or precise calibration of the cameras to improve results. An application of these developed systems in a realistic outdoor environment is often difficult. Our aim is to be widely independent from the camera setup and the observed scene, in order to use existing cameras. Thereby our algorithm needs to be capable to work with both overlapping and non-overlapping fields of views. We propose an algorithm that allows flexible combination of different static cameras with varying properties. Another requirement of a practical application is that the algorithm is able to work online. Our system is able to process the data during runtime and to provide results immediately. In addition to seeking flexibility in the camera setup, we present a specific approach that combines state of the art algorithms in order to be robust to environment influences. We present results that indicate a good performance of our introduced algorithm in different scenarios. We show its robustness to different types of image artifacts. In addition we demonstrate that our algorithm is able to match persons between cameras in a non-overlapping scenario.
NEW AIRBORNE SENSORS AND PLATFORMS FOR SOLVING SPECIFIC TASKS IN REMOTE SENSING
Authors: Kemper G.
Published: August 2012

Abstract. A huge number of small and medium sized sensors entered the market. Today's mid format sensors reach 80 MPix and allow to run projects of medium size, comparable with the first big format digital cameras about 6 years ago. New high quality lenses and new developments in the integration prepared the market for photogrammetric work. Companies as Phase One or Hasselblad and producers or integrators as Trimble, Optec, and others utilized these cameras for professional image production. In combination with small camera stabilizers they can be used also in small aircraft and make the equipment small and easy transportable e.g. for rapid assessment purposes. The combination of different camera sensors enables multi or hyper-spectral installations e.g. useful for agricultural or environmental projects. Arrays of oblique viewing cameras are in the market as well, in many cases these are small and medium format sensors combined as rotating or shifting devices or just as a fixed setup. Beside the proper camera installation and integration, also the software that controls the hardware and guides the pilot has to solve much more tasks than a normal FMS did in the past. Small and relatively cheap Laser Scanners (e.g. Riegl) are in the market and a proper combination with MS Cameras and an integrated planning and navigation is a challenge that has been solved by different softwares. Turnkey solutions are available e.g. for monitoring power line corridors where taking images is just a part of the job. Integration of thermal camera systems with laser scanner and video capturing must be combined with specific information of the objects stored in a database and linked when approaching the navigation point.
ASSESSING THE PHOTOGRAMMETRIC POTENTIAL OF CAMERAS IN PORTABLE DEVICES
Authors: Smith M. J. , Kokkas N.
Published: August 2012

Abstract. In recent years, there have been an increasing number of portable devices, tablets and Smartphone’s employing high-resolution digital cameras to satisfy consumer demand. In most cases, these cameras are designed primarily for capturing visually pleasing images and the potential of using Smartphone and tablet cameras for metric applications remains uncertain. The compact nature of the host’s devices leads to very small cameras and therefore smaller geometric characteristics. This also makes them extremely portable and with their integration into a multi-function device, which is part of the basic unit cost often makes them readily available. Many application specialists may find them an attractive proposition where some modest photogrammetric capability would be useful. This paper investigates the geometric potential of these cameras for close range photogrammetric applications by: • investigating their geometric characteristics using the self-calibration method of camera calibration and comparing results from a state-of-the-art Digital SLR camera. • investigating their capability for 3D building modelling. Again, these results will be compared with findings from results obtained from a Digital SLR camera. The early results presented show that the iPhone has greater potential for photogrammetric use than the iPad.
PHOTOGRAMMETRY AND LASER SCANNING FOR THE EARTH SCIENCESWORKING GROUP V6
Authors: Chandler J. H. , Buckley S. J. , Rieke-Zapp D. , Wackrow R.
Published: August 2012

Abstract. With the UK gaining responsibility for Commission V at the Beijing Congress in 2008, there was an opportunity to create a new working group focusing on earth science applications at close range. The earth science community has had a long tradition of using close range photogrammetry, and more recently laser scanning, and such opportunities have not been fully recognised by ISPRS in the past. Formation of a new ISPRS Working Group helps to bridge this gap and promotes the skills of ISPRS members more widely. The purpose of this paper is to justify the creation of Working Group V6 and identify some of the activities conducted over the last four years. In particular, reference will be made to the various technical sessions which have been organised and supported across the world, the first resulting in a Special Issue of The Photogrammetric Record published in September 2010. In addition, Working Group V6 has been responsible for the creation of two freely available guidance documents entitled "tips for the effective use of digital close range photogrammetry and terrestrial laser scanning". The former focuses on close range digital photogrammetry and has developed through several iterations with input from both academic and industrial users from around the world. For this reason it should be of distinct value to new and perhaps non-expert users interested in using photogrammetry for earth science applications. The paper includes a discussion which considers whether the initial four years of activity have been successful. A superficial assessment based upon the number of members attracted worldwide would suggest that this has indeed been the case. A deeper comparison between proposed activities and those actually achieved suggest some discrepancy, which is perhaps inevitable as Working Group Officers clearly have other responsibilities. However, examination of papers published in the earth surface journals reveal high incidence of photogrammetry and laser scanning appearing in recent work. This should encourage members of Working Group V6 in future activities and collaborations.
IN SITU MEASUREMENT OF BEDROCK EROSION
Authors: Rieke-Zapp D. H. , Beer A. , Turowski J. M. , Campana L.
Published: August 2012

Abstract. While long term erosion rates of bedrock material may be estimated by dating methods, current day erosion rates are – if at all available – based on rough estimates or on point measurements. Precise quantification of short term erosion rates are required to improve our understanding of short term processes, for input in landscape evolution models, as well as for studying the mechanics and efficiency of different erosion processes in varying geomorphological settings. Typical current day erosion rates in the European Alps range from sub-millimetre to several millimetres per year depending on the dominant erosion processes. The level of surveying accuracy required for recurring sub-millimetre to millimetre measurements in the field is demanding. A novel surveying setup for in-situ measurement of bedrock erosion was tested recently in three different locations in Switzerland. Natural bedrock was investigated in the Gornera gorge close to Zermatt. Further on, bedrock samples were installed in exposed locations in the Erlenbach research watershed close to Einsiedeln, and in the Illgraben debris flow channel, located in the Canton Schwyz and Valais, respectively. A twofold measurement approach was chosen for all locations. For the first setup control points providing an absolute reference frame for recurrent measurements were embedded close to the area of interest. Close range photogrammetry was applied to measure surface changes on the bedrock samples. The precision for surface measurements in the field was 0.1 mm (1 σ) and thus suitable for the application. The equipment needed for the surveys can easily be carried to the field. At one field site a structured light scanner was used along with the photogrammetric setup. Although the current generation of structured light scanners appeared less suitable for field application, data acquisition was much faster and checking the data for completeness in the field was straight forward. The latest generation of compact structured light scanners will probably be most suitable for similar applications.
Applications of Mobile GIS in Forestry South Australia
Authors: Battad D. T. , Mackenzie P.
Published: August 2012

Abstract. South Australian Forestry Corporation (ForestrySA) had been actively investigating the applications of mobile GIS in forestry for the past few years. The main objective is to develop an integrated mobile GIS capability that allows staff to collect new spatial information, verify existing data, and remotely access and post data from the field. Two (2) prototype mobile GIS applications have been developed already using the Environmental Systems Research Institute (ESRI) ARCGISR technology as the main spatial component. These prototype systems are the Forest Health Surveillance System and the Mobile GIS for Wetlands System. The Forest Health Surveillance System prototype is used primarily for aerial forest health surveillance. It was developed using a tablet PC with ArcMapR GIS. A customised toolbar was developed using ArcObjectsR in the Visual Basic 6 Integrated Development Environment (IDE). The resulting dynamic linked library provides a suite of custom tools which enables the following: - quickly create spatial features and attribute the data - full utilisation of global positioning system (GPS) technology - excellent screen display navigation tools, i.e. pan, rotate map, capture of flight path - seamless integration of data into GIS as geodatabase (GDB) feature classes - screen entry of text and conversion to annotation feature classes The Mobile GIS for Wetlands System prototype was developed for verifying existing wetland areas within ForestrySA’s plantation estate, collect new wetland data, and record wetland conditions. Mapping of actual wetlands within ForestrySA’s plantation estate is very critical because of the need to establish protection buffers around these features during the implementation of plantation operations. System development has been focussed on a mobile phone platform (HTC HD2R ) with WindowsR Mobile 6, ESRI’s ArcGISR Mobile software development kit (SDK) employing ArcObjectsR written on C#.NET IDE, and ArcGIS ServerR technology. The system is also implemented in the VILIVR X70. The system has undergone testing by ForestrySA staff and the refinements had been incorporated in the latest version of the system. The system has the following functionalities: - display and query strategic data layers - collect and edit spatial and attribute data - full utilisation of global positioning GPS technology - distance and area measurements - display of high resolution imagery - seamless integration of data into GIS as feature classes - screen display and navigation tools, i.e. pan, zoom in/out, rotate map - capture of flight path The next stages in the development of mobile GIS technologies at ForestrySA are to enhance the systems’ capabilities as one of the organization main data capture systems. These include incorporating other applications, e.g. roads/tracks mapping, mapping of significant sites, etc., and migration of the system to Windows Phone7.
AUTOMATIC CALIBRATION OF STEREO-CAMERAS USING ORDINARY CHESS-BOARD PATTERNS
Authors: Prokos A. , Kalisperakis I. , Petsa E. , Karras G.
Published: August 2012

Abstract. Automation of camera calibration is facilitated by recording coded 2D patterns. Our toolbox for automatic camera calibration using images of simple chess-board patterns is freely available on the Internet. But it is unsuitable for stereo-cameras whose calibration implies recovering camera geometry and their true-to-scale relative orientation. In contrast to all reported methods requiring additional specific coding to establish an object space coordinate system, a toolbox for automatic stereo-camera calibration relying on ordinary chess-board patterns is presented here. First, the camera calibration algorithm is applied to all image pairs of the pattern to extract nodes of known spacing, order them in rows and columns, and estimate two independent camera parameter sets. The actual node correspondences on stereo-pairs remain unknown. Image pairs of a textured 3D scene are exploited for finding the fundamental matrix of the stereo-camera by applying RANSAC to point matches established with the SIFT algorithm. A node is then selected near the centre of the left image; its match on the right image is assumed as the node closest to the corresponding epipolar line. This yields matches for all nodes (since these have already been ordered), which should also satisfy the 2D epipolar geometry. Measures for avoiding mismatching are taken. With automatically estimated initial orientation values, a bundle adjustment is performed constraining all pairs on a common (scaled) relative orientation. Ambiguities regarding the actual exterior orientations of the stereo-camera with respect to the pattern are irrelevant. Results from this automatic method show typical precisions not above 1/4 pixels for 640×480 web cameras.
STEREOVISION MOBILE MAPPING: SYSTEM DESIGN AND PERFORMANCE EVALUATION
Authors: Burkhard J. , Cavegn S. , Barmettler A. , Nebiker S.
Published: August 2012

Abstract. In this paper we introduce a state-of-the-art stereovision mobile mapping system with different stereo imaging sensors and present a series of performance tests carried out with this system. The aim of these empirical tests was to investigate different performance aspects under real-world conditions. The investigations were carried out with different cameras and camera configurations in order to determine their potential and limitations for selected application scenarios. In brief the test set consists of investigations in geometric accuracy, in radiometric image quality and in the extraction of 3d point clouds using dense matching algorithms. The first tests resulted in an absolute overall 3d accuracy of 4-5 cm depending mainly on the quality of the navigation system used for direct georeferencing. The relative point measurement accuracy was approx. 2 cm and 1 cm for the 2 megapixel and the 11 megapixel sensors respectively. In the second series of investigations we present results obtained by applying tone mapping algorithms often used for high dynamic range images (HDR). In our third series of tests refinements of the radiometric calibration of the stereo system and corrections of the vignetting resulted in an improved completeness of the depth map on the roadside environment. We conclude the paper with investigations in obtaining complete and accurate depth maps for a robust and accurate 3d monoplotting support in vision-based mobile mapping web services. For this we present first results obtained by interpolating incomplete areas in the disparity maps and by fusing the disparity maps with additional LiDAR data.
PANORAMIC EPIPOLAR IMAGE GENERATION FOR MOBILE MAPPING SYSTEM
Authors: Chen T. , Yamamoto K. , Chhatkuli S. , Shimamura H.
Published: August 2012

Abstract. The notable improvements on performance and low cost of digital cameras and GPS/IMU devices have caused MMSs (Mobile Mapping Systems) to be gradually becoming one of the most important devices for mapping highway and railway networks, generating and updating road navigation data and constructing urban 3D models over the last 20 years. Moreover, the demands for large scale visual street-level image database construction by the internet giants such as Google and Microsoft have made the further rapid development of this technology. As one of the most important sensors, the omni-directional cameras are being commonly utilized on many MMSs to collect panoramic images for 3D close range photogrammetry and fusion with 3D laser point clouds since these cameras could record much visual information of the real environment in one image at field view angle of 360° in longitude direction and 180° in latitude direction. This paper addresses the problem of panoramic epipolar image generation for 3D modelling and mapping by stereoscopic viewing. These panoramic images are captured with Point Grey’s Ladybug3 mounted on the top of Mitsubishi MMS-X 220 at 2m intervals along the streets in urban environment. Onboard GPS/IMU, speedometer and post sequence image analysis technology such as bundle adjustment provided high accuracy position and attitude data for these panoramic images and laser data, this makes it possible to construct the epipolar geometric relationship between any two adjacent panoramic images and then the panoramic epipolar images could be generated. Three kinds of projection planes: sphere, cylinder and flat plane are selected as the epipolar images’ planes. In final we select the flat plane and use its effective parts (middle parts of base line’s two sides) for epipolar image generation. The corresponding geometric relations and results will be presented in this paper.
THE RAILMAPPER – A DEDICATED MOBILE LIDAR MAPPING SYSTEM FOR RAILWAY NETWORKS
Authors: Kremer J. , Grimm A.
Published: August 2012

Abstract. The Mobile LiDAR Mapping System StreetMapper from IGI and 3D Laser Mapping (Bingham Nottingham, UK) is mounted on a large variety of road vehicles to cover different mission specifications. In addition to the operation on the road, the system finds its applications on other kinds of vehicles, like boats or trains. The modular and flexible system concept even allows utilizing the same LiDAR Mapping system for Mobile Mapping on the ground and for airborne missions on helicopters, respectively. Besides this general flexibility, each application has its own special requirements. Special hardware and software components are needed to complete the core components, like the laser scanner and the GNSS/IMU systems, to build a dedicated system for the chosen task. Compared to the typical dynamics of a road vehicle mounted Mobile Mapping system, a dedicated rail mapping system operates under conditions that are much more challenging for a high accuracy GNSS/IMU trajectory determination. Furthermore, the typical rail mapping tasks, like the exact measurement of the rail track geometry, require the operation of the most accurate laser scanners and of specialized post-processing software. In this paper, the RailMapper, a specialized Mobile Mapping system for railway surveys is presented. The system is described with focus on the railway specific requirements and results of practical surveys are given.
ERROR DISTRIBUTION EVALUATION OF THE THIRD VANISHING POINT BASED ON RANDOM STATISTICAL SIMULATION
Authors: Li C.
Published: August 2012

Abstract. POS, integrated by GPS / INS (Inertial Navigation Systems), has allowed rapid and accurate determination of position and attitude of remote sensing equipment for MMS (Mobile Mapping Systems). However, not only does INS have system error, but also it is very expensive. Therefore, in this paper error distributions of vanishing points are studied and tested in order to substitute INS for MMS in some special land-based scene, such as ground façade where usually only two vanishing points can be detected. Thus, the traditional calibration approach based on three orthogonal vanishing points is being challenged. In this article, firstly, the line clusters, which parallel to each others in object space and correspond to the vanishing points, are detected based on RANSAC (Random Sample Consensus) and parallelism geometric constraint. Secondly, condition adjustment with parameters is utilized to estimate nonlinear error equations of two vanishing points (VX, VY). How to set initial weights for the adjustment solution of single image vanishing points is presented. Solving vanishing points and estimating their error distributions base on iteration method with variable weights, co-factor matrix and error ellipse theory. Thirdly, under the condition of known error ellipses of two vanishing points (VX, VY) and on the basis of the triangle geometric relationship of three vanishing points, the error distribution of the third vanishing point (VZ) is calculated and evaluated by random statistical simulation with ignoring camera distortion. Moreover, Monte Carlo methods utilized for random statistical estimation are presented. Finally, experimental results of vanishing points coordinate and their error distributions are shown and analyzed.
DETERMINING PULL – OUT DEFORMATIONS OF BONDED METAL ANCHORS EMBEDDED IN CONCRETE BY MEANS OF PHOTOGRAMMETRY
Authors: Avsar E. O. , Altan M. O. , Dogan U. A. , Akca D.
Published: August 2012

Abstract. Chemical anchorages are applied in many engineering implementations, particularly strengthening of reinforced concrete structures. During strengthening procedure; chemical anchorages should be tested, since they supply to transfer the load between existing construction elements and newly added elements. Therefore; the study of the quality of chemical anchorages is an important issue in construction materials science. In this context; the most important experiment is to determine the pull-out loads of embedded anchorage reinforcement by applying axial loads. In this study; it is aimed to determine the displacements of steel reinforcements, embedded into concrete by using chemical anchorages, while applying axial pulling loads. In order to determine the displacements and load – deformation graphs; starting conditions and every 10 bar pressure applied conditions of the steel reinforcements were captured by the cameras. The obtained images were evaluated by using photogrammetric software. Based on the photogrammetric post-processing results, the load – deformation graphs were plotted and the loads at loss of adhesion were determined.
TERRESTRIAL LASER SCANNING FOR COASTAL GEOMORPHOLOGIC RESEARCH IN WESTERN GREECE
Authors: Hoffmeister D. , Tilly N. , Curdt C. , Aasen H. , Ntageretzis K. , Hadler H. , Willershäuser T. , Vött A. , Bareth G.
Published: August 2012

Abstract. We used terrestrial laser scanning (TLS) for (i) accurate volume estimations of dislocated boulders moved by high-energy impacts and for (ii) monitoring of annual coastal changes. In this contribution, we present three selected sites in Western Greece that were surveyed during a time span of four years (2008-2011). The Riegl LMS-Z420i laser scanner was used in combination with a precise DGPS system (Topcon HiPer Pro). Each scan position and a further target were recorded for georeferencing and merging of the point clouds. For the annual detection of changes, reference points for the base station of the DGPS system were marked. Our studies show that TLS is capable to accurately estimate volumes of boulders, which were dislocated and deposited inland from the littoral zone. The mass of each boulder was calculated from this 3D-reconstructed volume and according density data. The masses turned out to be considerably smaller than common estimated masses based on tape-measurements and according density approximations. The accurate mass data was incorporated into wave transport equations, which estimate wave velocities of high-energy impacts. As expected, these show smaller wave velocities, due to the incorporated smaller mass. Furthermore, TLS is capable to monitor annual changes on coastal areas. The changes are detected by comparing high resolution digital elevation models from every year. On a beach site, larger areas of sea-weed and sandy sediments are eroded. In contrast, bigger gravel with 30-50 cm diameter was accumulated. At the other area with bigger boulders and a different coastal configuration only slightly differences were detectable. In low-lying coastal areas and along recent beaches, post-processing of point clouds turned out to be more difficult, due to noise effects by water and shadowing effects. However, our studies show that the application of TLS in different littoral settings is an appropriate and promising tool. The combination of both instruments worked well and the annual positioning procedure with own survey point is precose for this purpose.
AN APPROACH TO FIND LOCALIZATION OF NON-EXISTENT HISTORICAL BUILDINGS BY TERRESTRIAL PHOTOGRAMMETRY
Authors: Acar U. , Bayram B. , Cetin H. I.
Published: August 2012

Abstract. Preservation of cultural and historical values located in Bosphorus Area in Turkey and protection of natural structure is guaranteed by Bosphorus Law. According to the law, land owners who want to raise a new building in Bosphorus area can only do exactly like the previously constructed building in that area. In the event that there is no construction whatsoever regarding the building in the area, information about the building that will be constructed can only be reached by historical photographs. The study that is presented is made with the purpose of identifying if the historical building that can only be reached by historical maps and photographs and is planned to be reconstructed in the Bosphorus area, is the building shown in photographs or not, and also if it is on the alleged area. Aerial photograph of 1937, actual 1/1000 scaled digital photogrammetric map and satellite image of the same area, historical perspective photograph that was taken between 1903-1907, actual photograph that was taken with around the same perspective and 3D Google Earth image which provides the same perspective are used for this process. Historical buildings that remain the same until today are confirmed by the historical aerial photograph which includes study area and these buildings are used as control point. In the same way, with the historical perspective photograph, buildings that reach until today are confirmed and used as control point. With the acquired results, that the building is totally in the alleged parcel is crosschecked with all methods and confirmed with the error of 1.8357 meters.
COSTLESS PLATFORM FOR HIGH RESOLUTION STEREOSCOPIC IMAGES OF A HIGH GOTHIC FACADE
Authors: Héno R. , Chandelier L. , Schelstraete D.
Published: August 2012

Abstract. In October 2011, the PPMD specialized master's degree students (Photogrammetry, Positionning and Deformation Measurement) of the French ENSG (IGN’s School of Geomatics, the Ecole Nationale des Sciences Géographiques) were asked to come and survey the main facade of the cathedral of Amiens, which is very complex as far as size and decoration are concerned. Although it was first planned to use a lift truck for the image survey, budget considerations and taste for experimentation led the project to other perspectives: images shot from the ground level with a long focal camera will be combined to complementary images shot from what higher galleries are available on the main facade with a wide angle camera fixed on a horizontal 2.5 meter long pole. This heteroclite image survey is being processed by the PPMD master's degree students during this academic year. Among other type of products, 3D point clouds will be calculated on specific parts of the facade with both sources of images. If the proposed device and methodology to get full image coverage of the main facade happen to be fruitful, the image acquisition phase will be completed later by another team. This article focuses on the production of 3D point clouds with wide angle images on the rose of the main facade.
HYDROLOGIC AND FEATURE-BASED SURFACE ANALYSIS FOR TOOL MARK INVESTIGATION ON ARCHAEOLOGICAL FINDS
Authors: Kovács K. , Hanke K.
Published: August 2012

Abstract. The improvement of detailed surface documentation methods provides unique tool mark-study opportunities in the field of archaeological researches. One of these data collection techniques is short-range laser scanning, which creates a digital copy of the object’s morphological characteristics from high-resolution datasets. The aim of our work was the accurate documentation of a Bronze Age sluice box from Mitterberg, Austria with a spatial resolution of 0.2 mm. Furthermore, the investigation of the entirely preserved tool marks on the surface of this archaeological find was also accomplished by these datasets. The methodology of this tool mark-study can be summarized in the following way: At first, a local hydrologic analysis has been applied to separate the various patterns of tools on the finds’ surface. As a result, the XYZ coordinates of the special points, which represent the edge lines of the sliding tool marks, were calculated by buffer operations in a GIS environment. During the second part of the workflow, these edge points were utilized to manually clip the triangle meshes of these patterns in reverse engineering software. Finally, circle features were generated and analysed to determine the different sections along these sliding tool marks. In conclusion, the movement of the hand tool could be reproduced by the spatial analysis of the created features, since the horizontal and vertical position of the defined circle centre points indicated the various phases of the movements. This research shows an exact workflow to determine the fine morphological structures on the surface of the archaeological find.
ARTEFACT MOBILE DATA MODEL TO SUPPORT CULTURAL HERITAGE DATA COLLECTION AND INTERPRETATION
Authors: Mohamed-Ghouse Z. S. , Kelly D. , Costello A. , Edmonds V.
Published: August 2012

Abstract. This paper discusses the limitation of existing data structures in mobile mapping applications to support archaeologists to manage the artefact (any object made or modified by a human culture, and later recovered by an archaeological endeavor) details excavated at a cultural heritage site. Current limitations of data structure in the mobile mapping application allow archeologist to record only one artefact per test pit location. In reality, more than one artefact can be excavated from the same test pit location. A spatial data model called Artefact Mobile Data Model (AMDM) was developed applying existing Relational Data Base Management System (RDBMS) technique to overcome the limitation. The data model was implemented in a mobile database environment called SprintDB Pro which was in turn connected to ArcPad 7.1 mobile mapping application through Open Data Base Connectivity (ODBC). In addition, the design of a user friendly application built on top of AMDM to interpret and record the technology associated with each artefact excavated in the field is also discussed in the paper. In summary, the paper discusses the design and implementation of a data model to facilitate the collection of artefacts in the field using integrated mobile mapping and database approach.
COMPARISON OF LOW ALTITUDE PHOTOGRAMMETRIC METHODS FOR OBTAINING DEMS AND ORTHOIMAGES OF ARCHAEOLOGICAL SITES
Authors: Mozas-Calvache A. T. , Pérez-García J. L. , Cardernal-Escarcena F. J. , Delgado J. , Mata-deCastro E.
Published: August 2012

Abstract. In this work it is performed a comparison of two methods for obtaining digital elevation models (DEMs) and orthoimages of medium-sized archaeological sites (500-5000 m2). The photogrammetric methods analyzed consist in the use of a light aerial platform applying the normal case of photogrammetry (vertical photographs and regular blocks), and the second one is based on a network of oblique photographs, taken from a telescopic mast, using a DEM obtained from a terrestrial laser scanner (TLS) survey. The main goal is to analyze the more efficient method for these studies taking into account variables such the working time, the accuracy obtained in the final products, the visual analysis of final orthoimages, etc. This study has been applied to the same archaeological site in two different epochs. The image acquisition was performed before and after a conservation intervention at the archaeological site. The results have shown similar characteristics for both products (DEMs and orthoimages) and accuracies but the density of DEMs and the visual analysis of orthoimages have shown differences that allows us to select the more adequate method taking into account the characteristics of each case. Thus the DEMs obtained using the TLS survey has shown more density of points while the visual analysis of orthoimages has shown a better behaviour (radiometrically and visually) in the case of vertical photographs.
ARCHAEOLOGICAL SITE MONITORING: UAV PHOTOGRAMMETRY CAN BE AN ANSWER
Authors: Rinaudo F. , Chiabrando F. , Lingua A. , Spanò A.
Published: August 2012

Abstract. During archaeological excavations it is important to monitor the new excavated areas and findings day by day in order to be able to plan future excavation activities. At present, this daily activity is usually performed by using total stations, which survey the changes of the archaeological site: the surveyors are asked to produce day by day draft plans and sections which allow archaeologists to plan their future activities. The survey is realized during the excavations or just at the end of every working day and drawings have to be produced as soon as possible in order to allow the comprehension of the work done and to plan the activities for the following day. By using this technique, all the measurements, even those not necessary for the day after, have to be acquired in order to avoid a ‘loss of memory’. A possible alternative to this traditional approach is aerial photogrammetry, if the images can be acquired quickly and at a taken distance able to guarantee the necessary accuracy of a few centimeters. Today the use of UAVs (Unmanned Aerial Vehicles) can be considered a proven technology able to acquire images at distances ranging from 4 m up to 20 m: and therefore as a possible monitoring system to provide the necessary information to the archaeologists day by day. The control network, usually present at each archaeological site, can give the stable control points useful for orienting a photogrammetric block acquired by using an UAV equipped with a calibrated digital camera and a navigation control system able to drive the aircraft following a pre-planned flight scheme. Modern digital photogrammetric software can solve for the block orientation and generate a DSM automatically, allowing rapid orthophoto generation and the possibility of producing sections and plans. The present paper describes a low cost UAV system realized by the research group of the Politecnico di Torino and tested on a Roman villa archaeological site located in Aquileia (Italy), a well-known UNESCO WHL site. The results of automatic orientation and orthophoto production are described in terms of their accuracy and the completeness of information guaranteed for archaeological site excavation management.
LASER SCANNER SURVEY TO CULTURAL HERITAGE CONSERVATION AND RESTORATION
Authors: Vacca G. , Deidda M. , Dessi A. , Marras M.
Published: August 2012

Abstract. The field of Cultural Heritage has inspired, in the course of last few years, an interest more and more important on behalf of scientific community that deals to survey. The idea that knowledge of a site doesn't apply only to its history but must necessarily include its characteristics of position, shape and geometry, is gathering pace. In Geomatic science the field of cultural heritage benefits to an integrated approach of techniques and different technologies. Every cultural site in fact, is a case in itself, with its own characteristics, problems and specificness. Current techniques offer opportunity to achieve new ways of representation and visualization of cultural site, with the aim of a better metric description. This techniques are powerful tools for analysis of sites and supports to activity of reconstruction and repair. Biggest expectations in this field is laser three-dimensional scanning technique; a system which is able to operate in a methodical way in speed of acquisition and in possibility to access data in real time. Documentation and filing of state of a monument or site is essential in case of reconstruction or conservative project. Possibility to detect very complex geometries with great accuracy allows an in depth study of constructive techniques, making analysis of geometrical details easier which is, with traditional techniques, difficult to achieve. Biggest problems about use of laser scanner survey are graphic outputs for restorers and architects, in fact they often don't know real potential of this techniques, methodologies and functionalities and they expect traditional outputs such as floor plans, cross sections and front elevation of cultural asset. Present study is focused on finding a workflow to support activity of study, restoration and conservative project of cultural heritage, extracting automatically (or with a limited manual operation) graphic outputs from laser scanner survey. Some procedure was tested on two case study the Siviller Castle (XV century), situated in Villasor, a city near Cagliari (Sardinia, Italy) and the tower bell of Mores, near Sassari (Sardinia, Italy). The cultural sites were surveyed with laser scanner Focus 3D by Faro and to process clouds point we were used the JRC 3D Reconstructor software
REAL TIME DATA PROCESSING FOR OPTICAL REMOTE SENSING PAYLOADS
Authors: Wohlfeil J. , Börner A. , Buder M. , Ernst I. , Krutz D. , Reulke R.
Published: August 2012

Abstract. The application of operational systems for remote sensing requires new approaches for data processing. It has to be the goal to derive user relevant information close the sensor itself and to downlink this information to a ground station or to provide them as input to an actuator of the space-borne platform. A complete automation of data processing is an essential first step for a thematic onboard data processing. In a second step, an appropriate onboard computer system has to be de-signed being able to fulfill the requirements. In this paper, standard data processing steps will be introduced correcting systematic errors during image capturing. A new hardware operating system, which is the interface between FPGA hardware and data processing algorithms, gives the opportunity to implement complex data processing modules in an effective way. As an example the derivation the camera's orientation based on data of an optical payload is described in detail. The thereby derived absolute or relative orientation is essential for high level data products. This will be illustrated by means of an onboard image matcher
HIGH RESOLUTION SURVEY OF PHAISTOS PALACE (CRETE) BY TLS AND TERRESTRIAL PHOTOGRAMMETRY
Authors: Fabris M. , Achilli V. , Artese G. , Bragagnolo D. , Menin A.
Published: August 2012

Abstract. Three-dimensional methodologies as Terrestrial Laser Scanning (TLS) and digital photogrammetry, are used to extract digital models of surfaces. In this paper, the two different approaches, integrated with classical topographic methodologies, were applied in the 3D survey of a portion of Phaistos Palace in Crete island. The archaeological site represents one of the most important document of the Minoan civilization. Leica HDS2500 Time of Flight laser scanner, Canon EOS 1 DS Mark II digital metric camera and Leica TC2003 total station were used. The aim is to evaluate if data with very different methodologies can be accurately co-registered, integrated and what are the limits of applicability. Results show the co-registration of data (average differences in the order of some centimetres) and a better capacity of laser scanning surfaces to describe the corrugated portions of the walls of Phaistos Palace.
MONTE-CARLO- SIMULATION FOR ACCURACY ASSESSMENT OF A SINGLE CAMERA NAVIGATION SYSTEM
Authors: Bethmann F. , Luhmann T.
Published: August 2012

Abstract. The paper describes a simulation-based optimization of an optical tracking system that is used as a 6DOF navigation system for neurosurgery. Compared to classical system used in clinical navigation, the presented system has two unique properties: firstly, the system will be miniaturized and integrated into an operating microscope for neurosurgery; secondly, due to miniaturization a single camera approach has been designed. Single camera techniques for 6DOF measurements show a special sensitivity against weak geometric configurations between camera and object. In addition, the achievable accuracy potential depends significantly on the geometric properties of the tracked objects (locators). Besides quality and stability of the targets used on the locator, their geometric configuration is of major importance. In the following the development and investigation of a simulation program is presented which allows for the assessment and optimization of the system with respect to accuracy. Different system parameters can be altered as well as different scenarios indicating the operational use of the system. Measurement deviations are estimated based on the Monte-Carlo method. Practical measurements validate the correctness of the numerical simulation results.
INCREASE OF READABILITY AND ACCURACY OF 3D MODELS USING FUSION OF CLOSE RANGE PHOTOGRAMMETRY AND LASER SCANNING
Authors: Gašparović M. , Malarić I.
Published: August 2012

Abstract. The development of laser scanning technology has opened a new page in geodesy and enabled an entirely new way of presenting data. Products obtained by the method of laser scanning are used in many sciences, as well as in archaeology. It should be noted that 3D models of archaeological artefacts obtained by laser scanning are fully measurable, written in 1:1 scale and have high accuracy. On the other hand, texture and RGB values of the surface of the object obtained by a laser scanner have lower resolution and poorer radiometric characteristics in relation to the textures captured with a digital camera. Scientific research and the goal of this paper are to increase the accuracy and readability of the 3D model with textures obtained with a digital camera. Laser scanning was performed with triangulation scanner of high accuracy, Vivid 9i (Konica Minolta), while for photogrammetric recording digital camera Nikon D90 with a lens of fixed focal length 20 mm, was used. It is important to stress that a posteriori accuracy score of the global registration of point clouds in the form of the standard deviation was ± 0.136 mm while the average distance was only ± 0.080 mm. Also research has proven that the quality projection texture model increases readability. Recording of archaeological artefacts and making their photorealistic 3D model greatly contributes to archaeology as a science, accelerates processing and reconstruction of the findings. It also allows the presentation of findings to the general public, not just to the experts.
STEREOMETRIC MODELLING
Authors: Grimaldi P.
Published: August 2012

Abstract. These mandatory guidelines are provided for preparation of papers accepted for publication in the series of Volumes of The The stereometric modelling means modelling achieved with : – the use of a pair of virtual cameras, with parallel axes and positioned at a mutual distance average of 1/10 of the distance camera-object (in practice the realization and use of a stereometric camera in the modeling program); – the shot visualization in two distinct windows – the stereoscopic viewing of the shot while modelling. Since the definition of "3D vision" is inaccurately referred to as the simple perspective of an object, it is required to add the word stereo so that "3D stereo vision " shall stand for "three-dimensional view" and ,therefore, measure the width, height and depth of the surveyed image. Thanks to the development of a stereo metric model , either real or virtual, through the "materialization", either real or virtual, of the optical-stereo metric model made visible with a stereoscope. It is feasible a continuous on line updating of the cultural heritage with the help of photogrammetry and stereometric modelling. The catalogue of the Architectonic Photogrammetry Laboratory of Politecnico di Bari is available on line at: http://rappresentazione.stereofot.it:591/StereoFot/FMPro?-db=StereoFot.fp5&-lay=Scheda&-format=cerca.htm&-view