Open software and standards in the realm of laser scanning technology

Abstract This review aims at introducing laser scanning technology and providing an overview of the contribution of open source projects for supporting the utilization and analysis of laser scanning data. Lidar technology is pushing to new frontiers in mapping and surveying topographic data. The open source community has supported this by providing libraries, standards, interfaces, modules all the way to full software. Such open solutions provide scientists and end-users valuable tools to access and work with lidar data, fostering new cutting-edge investigation and improvements of existing methods. The first part of this work provides an introduction on laser scanning principles, with references for further reading. It is followed by sections respectively reporting on open standards and formats for lidar data, tools and finally web-based solutions for accessing lidar data. It is not intended to provide a thorough review of state of the art regarding lidar technology itself, but to provide an overview of the open source toolkits available to the community to access, visualize, edit and process point clouds. A range of open source features for lidar data access and analysis is provided, providing an overview of what can be done with alternatives to commercial end-to-end solutions. Data standards and formats are also discussed, showing what are the challenges for storing and accessing massive point clouds. The desiderata are to provide scientists that have not yet worked with lidar data an overview of how this technology works and what open source tools can be a valid solution for their needs in analysing such data. Researchers that are already involved with lidar data will hopefully get ideas on integrating and improving their workflow through open source solutions

Metrological characterization of 3D imaging systems: progress report on standards developments

A significant issue for companies or organizations integrating non-contact three-dimensional (3D) imaging systems into their production pipeline is deciding in which technology to invest. Quality non-contact 3D imaging systems typically involve a significant investment when considering the cost of equipment, training, software, and maintenance contracts over the functional lifetime of a given system or systems notwithstanding the requirements of the global nature of manufacturing activities. Numerous methods have been published to “help” users navigate the many products and specifications claims about “quality”. Moreover, the “best” system for one application may not be ideally suited for another application. The lack of publically-available characterization methods from trusted sources for certain areas of 3D imaging make it difficult for a typical user to select a system based on information written on a specification sheet alone. An internationally-recognized standard is a vehicle that allows better communication between users and manufacturers. It is in this context that we present a progress report on standards developments to date in the diverse, but finite, world of non-contact 3D imaging systems from the nanometre to the 100 m range

Enhanced Interaction Experience for Holographic Visualization

Nowadays, holographic visualization pushes further the limits in exploring tri-dimensional digital con-tent. 3D models typically displayed through a computer screen now enter the real world as holograms. The Hologram Table allows users to visualize and manipulate huge 3D models as if they were in the space in front of them. Its use has already proved helpful for the virtual fruition and presentation of complex cultural heritage buildings and their design interventions, but it surely can do more. The work aims at exploring the possibility of expanding the capabilities of the Hologram Table interaction by developing a custom-designed experience to interact with 3D point cloud data coming from survey activity. The test case was the interesting building of the Santa Maria delle Grazie (Milan, Italy) basilica. Initial results are encouraging and show that the point model can be enriched with associated information and additional content (images and texts) available for holographic visualization

Characterization of Macro- and Micro-Geomorphology of Cave Channel from High-Resolution 3D Laser Scanning Survey: Case Study of Gomantong Cave in Sabah, Malaysia

Three-dimensional documentation of hypogene cave morphology is one of the major applications of laser scanning survey. This chapter presents applications of terrestrial laser scanning (TLS) survey for analyzing endogenic cave passage geomorphologic structure and morphometry using 3D meshing, high-resolution 3D texture modeling for geovisualization, and its potential for cave art documentation. To achieve this, multi-scale resolution 3D models were generated; one using the mesh model for macro-morphological analysis and the other with the full-resolution scan to produce high quality 3D texture model for identification of micro-morphological features. The mesh model of the cave makes it possible to analyze the general shape, distinguish phreatic tube from post-speleogenetic modified conduits and carry out morphometric measurements including the cave volume and channel surface area. The 3D texture model provides true to live visualization of the cave with exceptionally high level of accuracy and details that would be impossible to obtain with direct observation by visiting the site or from the mesh model. The model allows discerning different speleogenetic phases, karstification processes and micro-morphologies such as wall and ceiling seepage, hanging rocks, fractures, scallops, ceiling flush dome, pockets, bell-hole and avens. Also, the texture model permits identifying cave arts and engravings along the passage

An overview of information technology standardization activities related to additive manufacturing

This is a post-peer-review, pre-copyedit version of an article published in Progress in Additive Manufacturing. The final authenticated version is available online at: https://link.springer.com/article/10.1007%2Fs40964-019-00087-

NOSQL For Storage and Retrieval of Large LiDAR Data Collections

Developments in LiDAR technology over the past decades have made LiDAR to become a mature and widely accepted source of geospatial information. This in turn has led to an enormous growth in data volume. The central idea for a file-centric storage of LiDAR point clouds is the observation that large collections of LiDAR data are typically delivered as large collections of files, rather than single files of terabyte size. This split of the dataset, commonly referred to as tiling, was usually done to accommodate a specific processing pipeline. It makes therefore sense to preserve this split. A document oriented NoSQL database can easily emulate this data partitioning, by representing each tile (file) in a separate document. The document stores the metadata of the tile. The actual files are stored in a distributed file system emulated by the NoSQL database. We demonstrate the use of MongoDB a highly scalable document oriented NoSQL database for storing large LiDAR files. MongoDB like any NoSQL database allows for queries on the attributes of the document. As a specialty MongoDB also allows spatial queries. Hence we can perform spatial queries on the bounding boxes of the LiDAR tiles. Inserting and retrieving files on a cloud-based database is compared to native file system and cloud storage transfer speed

Combinación de nube de puntos proveniente de un drone fotogramétrico de ala fija con la generada por una estación Trimble SX10 (Escáner + Estación total + Estación fotogramétrica)

Trabajo de Fin de Máster del Máster en Geotecnologías cartográficas en ingeniería y arquitectura, curso...[ES]El trabajo se encuadra en la confluencia de la tecnología LIDAR y la fotogrametría. Mediante la tecnología LIDAR se obtienen nubes de puntos georreferenciadas. En función de la configuración que se determine par el proyecto a realizar, y a las limitaciones técnicas del equipo empleado, se podrá obtener una nube de puntos más o menos densa. Es decir, con más detalle respecto a la realidad sobre la que se quiere trabajar. En el ámbito de la fotogrametría, las específicas características de la geometría epipolar, a partir de imágenes consecutivas con suficiente solapa, facilita la obtención de coordenadas espaciales de puntos identificados en las mismas. A partir de ese concepto, si se dan las características adecuadas, se podrán identificar un número indeterminado de puntos georreferenciados, los cuales constituirán una nube de puntos. En función de las características del objeto sobre el que se quiera trabajar, y de las limitaciones de los equipos con que se cuente para realizar el trabajo, se podrán combinar ambas tecnologías para obtener una única nube de puntos

Multimodal spatial mapping and visualisation of Dinaledi Chamber and Rising Star Cave

The Dinaledi Chamber of the Rising Star Cave has yielded 1550 identifiable fossil elements – representing the largest single collection of fossil hominin material found on the African continent to date. The fossil chamber in which Homo naledi was found was accessible only through a near-vertical chute that presented immense practical and methodological limitations on the excavation and recording methods that could be used within the Cave. In response to practical challenges, a multimodal set of recording and survey methods was thus developed and employed: (1) recording of fossils and the excavation process was achieved through the use of white-light photogrammetry and laser scanning; (2) mapping of the Dinaledi Chamber was accomplished by means of high-resolution laser scanning, with scans running from the excavation site to the ground surface and the cave entrance; (3) at ground surface, the integration of conventional surveying techniques as well as photogrammetry with the use of an unmanned aerial vehicle was applied. Point cloud data were used to provide a centralised and common data structure for conversion and to corroborate the influx of different data collection methods and input formats. Data collected with these methods were applied to the excavations, mapping and surveying of the Dinaledi Chamber and the Rising Star Cave. This multimodal approach provides a comprehensive spatial framework from individual bones to landscape level

Ingest and Storage of 3D Objects in a Digital Preservation System

The DURAARK project is developing methods and tools for the Long-Term Preservation (LTP) of architectural knowledge, including approaches to: enrich Building Information Models with “as built” information from scans, semantically enrich building models with additional data sets, preserve 3D models for future reuse. This deliverable defines the necessary steps for ingest and storage of 3D objects into anexisting OAIS compliant digital preservation system. It discusses how the gaps, which were previously identified and presented in deliverable D6.6.1, have been addressed in the DURAARK project so far. Developed methods and tools will be run against the DURAARK test set. Lastly, the existing drafts of the metadata schemas buildm for descriptive information and e57m and ifcm as technical metadata schemas for E57 and IFC respectively, will be extended significantly and presented in a digital preservation context