The little-known Roman gold mining site "Gralheira" is located near the well-explored mine of Tresminas. The 2.5 km long, almost dead straight archaeological monument from the first and second centuries AD is currently under threat from possible mining activities on the one hand and from modern waste disposal in the pits on the other. Since 2019, the Roman mining traces have been investigated by means of intensive field inspections, terrestrial 3d laser scanning and aerial photography. The following article will present first impressions and findings on this structure, as well as questions and preliminary interpretations.

In the Roman goldmine district of Tresminas, Gralheira and Campo de Jales in Northern Portugal many remains of prospection survived due to the hard stone in situ and the largely absent destruction in the following periods. The spiral stairwell in the Corta da Ribeirinha deviating several times rectangularly, presents a peculiarity among the galleries and shafts. Its remarkable architecture is the result from situational technical and mining conditions. Numerous changes in planning indicate that the final appearance expresses the changing aims and approaches during its construction. As for mining this can only be interpreted as a reaction to the exploitation of precious metal concentrations. Due to the angles of stairs, lengths of straight sections and deviating angles of shafts and galleries it was possible to change the course and end of the building almost at every moment during its construction and therefore react directly on local prospection results without new extensive surveys.

Topographic mapping is a standard surveying task and the instrument of choice used to be a total station. The use of terrestrial laser scanning has become popular over the past decade or more, but today there is a much wider choice of methods for the acquisition of a digital surface model (DSM). For the 3D recording of an early mediaeval ring fort, the authors investigated the use of three modern systems: a portable (kinematic) laser scanning system, a static terrestrial laser scanning system (TLS) and a photogrammetric unmanned aerial system (UAS). The systems were compared to each other based on the following criteria: efficiency and performance in the field, degree of automation for data processing, and accuracy achieved in relation to the system costs.

To enter the Port of Hamburg, one of Europe’s busiest ports all vessels need to navigate around 145 km along the Elbe river, a tide influenced navigation channel. To protect the Elbe shoreline from erosion and to channel the waterway groynes (rigid hydraulic structures) have been built along the river. In the past years since ca. 2001 there has been a large increase in damage of groynes structural integrity at parts of the German waterways. The reason for this was determined in the ever growing size of container vessels passing by and inducing long periodical primary waves which have such a force that they erode the groynes rock structure. To analyse and improve the groynes structural resistance for vessel-induced long periodical wave loads an in-situ study is carried out at Juelssand, located at the Elbe river estuary. Over a period of two years the change of the geometrical structure of two different groyne shapes is monitored automatically by utilising two terrestrial laser scanners mounted in protective housings, located each on a 12 m high platform. The self-contained monitoring systems perform scanning of the two groynes one to two times a day at low tide, as the structures are fully submerged at high tide. The long-periodical wave loads are also determined using pressure sensors in each groyne. To correlate the captured data with vessel events and analyse the effects, vessel related parameters are recorded utilizing the Automatic Identification System (AIS). This paper describes the automated processes for the data acquisition and focusses on the deformation that is calculated using current, extended and new algorithms of the Point Cloud Library. It shows the process chain from the acquisition of raw scan files from an elevated station to the filtering of point cloud, the registration, the calculation of pointwise changes and the aggregation to a grid for later correlation with ship parameters. When working outdoor in all kinds of weather conditions, the processes and equipment need to be robust and account for various cases and situations. This is especially applicable for the algorithms, which need to be adaptable to different scenarios like wet surfaces or snow and unwelcome objects ranging from flotsam to birds sitting on the groyne. At the current stage of the research, deformation in the magnitude of a couple of decimetres is observable. The orientation and location of the deformation is on the seaward side and corresponds to the lower distance of vessels leaving the harbour.

297 141. Jg. 5/2016 zfv DOI 10.12902/zfv-0132-2016 Zusammenfassung Zur Einfahrt in den Hamburger Hafen werden ca. 120 km des tidebeeinflussten Abschnitts der Elbe, die Unterund Außenelbe, durchquert. Für den Schutz der Uferzonen sind Buhnen, spezielle Strömungsbauwerke, in den Flusslauf eingebracht. Seit ca. 2001 werden Schäden an den Buhnen festgestellt, die eine regelmäßige und teure Ertüchtigung der Bauwerke erforderlich machen. Die Ursache scheint in der erhöhten Elbbefahrung von immer größeren Schiffen gefunden zu sein. Die Schiffe verursachen bei der Durchquerung des Elbabschnittes starke langperiodische Wellenbelastungen, die sowohl Buhnen erodieren lassen, als auch zu Durchbrüchen führen. Im Unterelbeabschnitt Juelssand wird im Rahmen eines Naturversuchs der Bundesanstalt für Wasserbau und des Wasserstraßenund Schifffahrtsamtes Hamburg die Stabilität unterschiedlicher Bauformen und -weisen erprobt, um eine probabilistische Bemessung der Deckwerke zu ermöglichen. Die Dokumentation der Veränderungen erfolgt durch geodätisches Monitoring, welches in Kooperation mit der HafenCity Universität Hamburg entwickelt und ausgeführt wird. Gekapselt in ein schützendes Gehäuse werden Laserscans der Buhnenoberfläche jeweils bei Niedrigwasser vollautomatisch durchgeführt. Mit zwei identischen Messsystemen werden jeweils von einer 12 m hohen Messplattform Daten von zwei Buhnen erfasst. Durch einen 3D-Vergleich zu der Nullepoche werden die aufgetretenen Deformationen beschrieben. Ein Zusammenhang zwischen den verursachten Schäden und einzelnen Schiffspassagen kann hergestellt werden. Dafür werden wichtige Parameter zu den vorbeifahrenden Schiffen vom Automatischen Informationssystem (AIS) geliefert, während die schiffsinduzierten langperiodischen Wellenbelastungen mit Hilfe von in der Buhne verteilten Drucksonden gemessen werden.

Das Labor für Photogrammetrie & Laserscanning der HafenCity Universität Hamburg hat im Rahmen einer Messexkursion vom 26. bis zum 29. Mai 2015 die Ringwallanlage Lembecksburg, ein gut erhaltener, stattlicher Ringwall 1 km nördlich des Dorfes Borgsum auf der Insel Föhr (Landkreis Nordfriesland), mit verschiedenen Verfahren dreidimensional erfasst. Während der Messexkursion wurden für eine 3D-Dokumentation des archäologischen Denkmals folgende Messverfahren eingesetzt: a) Topographische Aufnahme mit dem Tachymeter, b) Topographische Aufnahme mit GNSS, c) Statisches terrestrisches Laserscanning, d) Kinematisches (mobiles) Laserscanning mit dem portablen Aufnahmesystem der Firma p3d systems GmbH und e) Luftbildaufnahme mit einem Unmanned Aerial Vehicle (Hexacopter). Die eingesetzten Messsysteme bzw. -verfahren wurden geometrisch und wirtschaftlich miteinander verglichen.

Durch den zunehmenden Handelsverkehr mit immer größeren Schiffen auf Seeschifffahrtsstraßen wie der Elbe nimmt die Belastung auf Strombauwerke wie Buhnen durch langperiodische Wellen zu. Bis jetzt gibt es allerdings kaum quantitative Aussagen, die den Zusammenhang zwischen der schiffsinduzierten Belastung und den auftretenden Schäden beschreiben. Dieser Beitrag stellt ein Messsystem vor, mit dem Deformationen an Buhnen quantifiziert werden können. Für diese Aufgabe wurde ein Monitoring-System konzipiert, aufgebaut und anhand eines Projektes erprobt. Mit einem terrestrischen Laserscanner als Messsensor wird automatisch bei jedem Niedrigwasser die Oberfläche der Buhne erfasst, um daraus flächenhaft Deformationen im Vergleich zu einem Referenzmodell abzuleiten. Die Systemkomponenten umfassen neben der Messsensorik und dem Gehäuse auch die notwendige Stromversorgung und Funkanbindung, um den dauerhaften Betrieb an einem entfernten Ort sicherzustellen zu können.

In September 2011 the fortress Al Zubarah, built in 1938 as a typical Arabic fortress and restored in 1987 as a museum, was recorded by the HafenCity University Hamburg using terrestrial laser scanning with the IMAGER 5006h and digital photogrammetry for the Qatar Museum Authority within the framework of the Qatar Islamic Archaeology and Heritage Project. One goal of the object recording was to provide detailed 2D/3D documentation of the fortress. This was used to complete specific detailed restoration work in the recent years. From the registered laser scanning point clouds several cuttings and 2D plans were generated as well as a 3D surface model by triangle meshing. Additionally, point clouds and surface models were automatically generated from digital imagery from a Nikon D70 using the open-source software Bundler/PMVS2, free software VisualSFM, Autodesk Web Service 123D Catch beta, and low-cost software Agisoft PhotoScan. These outputs were compared with the results from terrestrial laser scanning. The point clouds and surface models derived from imagery could not achieve the same quality of geometrical accuracy as laser scanning (i.e. 1–2 cm).

One of the most unique and remote areas on Earth, is Easter Island, which is well known for its huge volcanic rock statues called Moai by the islanders. Since 1995, the Moai have been protected as UNESCO (United Nations Educational, Scientific and Cultural Organization) World Cultural Heritage monuments. But so far, although the Moai are increasingly at risk of damage by animals, by exposure to weather (erosion) or by human vandalism, they have not been digitally documented and copied using an appropriate technique. Today, most of the more than 900 statues are in poor condition.

In diesem Beitrag werden erste Untersuchungsergebnisse der neuesten Generation folgen-der Phasenvergleichsscanner vorgestellt: Trimble FX und Faro Photon 80 im Vergleich zum IMAGER 5006 von Zoller + Frohlich. Alle drei Scanner konnen aufgrund ihrer techni-schen Parameter in ahnlichen Marktsegmenten (z. B. Industrie) eingesetzt werden. Die Untersuchungen wurden genauso wie fruhere und bereits publizierte Prufverfahren am Department Geomatik der HafenCity Universitat (HCU) Hamburg durchgefuhrt, um so eine Vergleichbarkeit mit den Ergebnissen fruherer Kampagnen gewahrleisten zu konnen. Erganzend wurden jedoch aus den Messungen auch Kenngrosen berechnet, die von ande-ren Autoren (H

Currently the second, or for some manufacturers even the third, generation of terrestrial laser scanning systems is available on the market. Although the new generation of terrestrial 3D laser scanning offers several new (geodetic) features and better performance, it is still essential to test the accuracy behaviour of the new systems for optimised use in each application. As a continuation of previously published investigations the Department Geomatics of the HafenCity University Hamburg (HCU Hamburg) carried out comparative investigations into the accuracy behaviour of the new generation of terrestrial laser scanning systems (Trimble GX, Leica ScanStation 1 and 2, and Riegl LMS420i using time-of-flight method, Leica HDS6000, Z+F IMAGER 5006, and Faro LS880 HE using phase difference method). The results of the following tests are presented and discussed in this paper: test field for 3D accuracy evaluation of 3D laser scanning systems, accuracy tests of distance measurements in comparison to reference distances, accuracy tests of inclination compensation, and influence of the laser beam’s angle of incidence on 3D accuracy.

SUMMARY The terrestrial laser scanning system Trimble GS100 was used in two projects for geometrical building inspection. In this paper, two projects, a water tower and an underground tunnel in Hamburg, are presented wherein geometrical building parameters and discrete points are de- rived from laser scanning data with the goal of inspecting existing buildings relative to con- struction plans. Using data acquired by laser scanning as-built measurements could be com- pared with building plans to determine deviations and possible collisions. The results achieved in these projects demonstrate clearly that terrestrial laser scanning data allows very extensive inspection of buildings due to the high geometrical quality of the point clouds. However, if increased precision (of better than 2mm) is required, the performance potential of the laser scanning system is limited. Since extensive CAD modelling was not necessary for these particular projects very fast results (up to a factor of 1:1 for the ratio of scanning to data processing) have been produced. ZUSAMMENFASSUNG Das terrestrische Laserscanning System Trimble GS100 wurde in zwei Projekten zur Untersuchung von Bauwerken eingesetzt. In diesem Beitrag werden mit dem Wasserturm und dem U-Bahntunnel in Hamburg zwei Projekte vorgestellt, bei denen geometrische Parameter des Gebäudes und diskrete Punkte aus Laserscanningdaten abgeleitet werden, um existierende Gebäude mit Bauplänen zu überprüfen. Anhand der mit dem Laserscanner gewonnenen Daten konnten Bauwerksplanungen mit dem Ist-Bestand hinsichtlich Abweichungen und Kollisionen überprüft werden. Die Ergebnisse zeigen, dass aus Laserscanningdaten abgeleitete Werte sehr umfangreiche Prüfungen zulassen, und dass jedoch bei erhöhten Genauigkeitsanforderungen (von besser als 2 mm) das System an seine Grenzen stößt. Da umfangreiche CAD-Modellierungsarbeiten nicht erforderlich waren, konnten sehr schnell Ergebnisse (bis zu Faktor 1:1 für das Verhältnis Erfassung/Auswertung) erzeugt werden.

SUMMARY Currently the second, or for some manufacturers even the third, generation of terrestrial laser scanning systems is available on the market. Although the new generation of terrestrial 3D laser scanning offers several new (geodetic) features and better performance, it is still essen- tial to test the accuracy behaviour of the new systems for optimised use in each application. As a continuation of previously published investigations the Department Geomatics of the HafenCity University Hamburg (HCU Hamburg) carried out comparative investigations into the accuracy behaviour of the new generation of terrestrial laser scanning systems (Trimble GX, Leica ScanStation 1 and 2, and Riegl LMS420i using time-of-flight method, Leica HDS6000, Z+F IMAGER 5006, and Faro LS880 HE using phase difference method). The results of the following tests are presented and discussed in this paper: test field for 3D accu- racy evaluation of 3D laser scanning systems, accuracy tests of distance measurements in comparison to reference distances, accuracy tests of inclination compensation, and influence of the laser beam's angle of incidence on 3D accuracy.

Although terrestrial 3D laser scanning is being used increasingly for a wide range of applications, no laser scanning system on the market is suitable for all applications. Conse- quently, it is essential to test the accuracy and behaviour of new laser scanning systems for optimised use in each application. In this paper investigations at Hamburg University of Ap- plied Sciences (HAW Hamburg) into the accuracy behaviour of the terrestrial laser scanning system Mensi GS100 from Trimble will be presented. Tests into the accuracy of point cloud registration and geo-referencing using reference distance measurements showed that there were significant discrepancies in the distances to spheres and to targets. In further investiga- tions it could be indicated that the quality of the scanned point cloud is influenced by instru- mental errors (trunnion axis error) and by the surface characteristics (colour, material and sur- face roughness) of scanned objects.

Although terrestrial 3D laser scanning is being used increasingly for a wide range of applications, no laser scanning system on the market is suitable for all applications. Conse- quently, it is essential to test the accuracy and behaviour of new laser scanning systems for optimised use in each application. In this paper investigations at Hamburg University of Ap- plied Sciences (HAW Hamburg) into the accuracy behaviour of the terrestrial laser scanning system Mensi GS100 from Trimble will be presented. Tests into the accuracy of point cloud registration and geo-referencing using reference distance measurements showed that there were significant discrepancies in the distances to spheres and to targets. In further investiga- tions it could be indicated that the quality of the scanned point cloud is influenced by instru- mental errors (trunnion axis error) and by the surface characteristics (colour, material and sur- face roughness) of scanned objects.

3D terrestrial laser scanning is well on the way to proving itself to be a 3D measurement technique that can complement or replace the established techniques of photogrammetry and tacheometry. For this reason investigations into accuracies and behavior are very important for the understanding and improvement of such measuring systems. The Department of Geomatics at Hamburg University of Applied Sciences has investigated the terrestrial 3D laser scanning system Mensi GS100/GS200 regarding the accuracy of distances measured and practical handling of the equipment in projects. It can be stated that distances measured with the laser scanner Mensi GS100 are systematically too long when compared to reference distances and that distances measured to spheres and targets placed on identical points are systematically different. In registration and geo-referencing of point clouds using Mensi spheres and targets in a 3D test field standard deviations of approx. 3mm could be achieved when compared to reference points. Investigations into the planarity of a stone slab showed measurement noise of some millimeters in the point cloud; which is within the range of the measuring accuracy. The laser scanners Mensi GS100 and GS200 have already been used in several projects at the HAW Hamburg and also in co-operation with a private engineering office. First experiences in data acquisition, registration and georeferencing will be reported in this paper using both systems.

3D terrestrial laser scanning is well on the way to proving itself to be a 3D measurement technique that can complement or replace the established techniques of photogrammetry and tacheometry. For this reason investigations into accuracies and behavior are very important for the understanding and improvement of such measuring systems. The Department of Geomatics at Hamburg University of Applied Sciences has investigated the terrestrial 3D laser scanning system Mensi GS100/GS200 regarding the accuracy of distances measured and practical handling of the equipment in projects. It can be stated that distances measured with the laser scanner Mensi GS100 are systematically too long when compared to reference distances and that distances measured to spheres and targets placed on identical points are systematically different. In registration and geo-referencing of point clouds using Mensi spheres and targets in a 3D test field standard deviations of approx. 3mm could be achieved when compared to reference points. Investigations into the planarity of a stone slab showed measurement noise of some millimeters in the point cloud; which is within the range of the measuring accuracy. The laser scanners Mensi GS100 and GS200 have already been used in several projects at the HAW Hamburg and also in co-operation with a private engineering office. First experiences in data acquisition, registration and georeferencing will be reported in this paper using both systems.

In diesem Beitrag wird der Einsatz des terrestrischen 3D-Laserscanning-Systems Mensi GS100/GS200 von Trimble im Fachbereich Geomatik an der Hochschule für Angewandte Wissenschaften Hamburg bei der topographischen Geländeaufnahme anhand von zwei Projekten vorgestellt. Die sächsische Ringwallanlage in Willen- scharen (Schleswig-Holstein) wurde mit dem Mensi GS100 gescannt, um aus der ge- samten Punktwolke einen Höhenlinienplan 1: 1000 abzuleiten. Außerdem wurde der Mensi GS200 zur beidseitigen Erfassung von ca. 1 km Uferböschungen der Tisza bei der Ortschaft Tiszavárkony (Ungarn) eingesetzt, um aus den Punktwolken ein digita- les Geländemodell zu erstellen, das als Datengrundlage für Simulationsberechnun- gen von Überschwemmungen dienen soll. Die Qualität der aus den Laserscannerda- ten modellierten digitalen Geländemodelle wird mit Referenzdaten verglichen und die Effizienz der Datenerfassung kritisch diskutiert.