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3D LASER SCANNERS: HISTORY, APPLICATIONS, AND FUTURE
Abstract and Figures
A 3D scanner is a device that analyzes a real-world object or environment to collect data on its shape and possibly its appearance (i.e. color). The collected data can then be used to construct digital three-dimensional models.
3D laser scanning developed during the last half of the 20th century in an attempt to accurately recreate the surfaces of various objects and places. The technology is especially helpful in fields of research and design. The first 3D scanning technology was created in the 1960s. The early scanners used lights, cameras and projectors to perform this task. Due to limitations of the equipment it often took a lot of time and effort to scan objects accurately. After 1985 they were replaced with scanners that could use white light, lasers and shadowing to capture a given surface.
Many different technologies can be used to build these 3D scanning devices; each technology comes with its own limitations, advantages, and costs. Many limitations in the kind of objects that can be digitized are still present: for example, optical technologies encounter many difficulties with shiny, mirroring, or transparent objects.
There are several different kinds of 3D laser scanners, with prices ranging from the couple thousands to the hundreds of thousands.
Collected 3D data is useful for a wide variety of applications. These devices are used extensively by the entertainment industry in the production of movies and video games. Other common applications of this technology include industrial design, orthotics and prosthetics, reverse engineering and prototyping, quality control/inspection and documentation of cultural artifacts.
The 3D Laser Scanning market including hardware, software, and services is rather dynamic with major segments experiencing rapid product innovation. The market contains exceptional opportunities with rapid forecasted growth driven by both replacing older mechanical methods, and by improved workflow with lower overall project costs, which enables more projects. For the forecast period (2010 – 2015), the market is forecasted to grow with a Compound Annual Growth Rate (CAGR) of 15.4% according to a new ARC Advisory Group study.
In this review article, the important areas concerning the 3D laser scanners will be covered.
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... Finally, one of the greatest outcomes of thesetechniques (Photogrammetry &laser scanners) is the possibility to obtain a large amount of very dense points called "point cloud" which can be used to generate very sophisticated 3D models which is are used to do further engineering analysis and studies. [25], [26], [27]. The goal of this study is to use surveying techniques (Photogrammetry & laser scanners) to detect and monitor thecracks and deflection in a reinforced concretestructure.The 3D measurements obtained by these techniques and those obtained by traditional methods are compared together to provide a better view on the accuracy and error of the proposed surveying techniques.The experiment was done on a reinforced concrete beam prepared in the material lab at the University of Kafr El-sheikh, then the beam was loaded and tested by a 4-point load test. ...
... Laser scanners are instruments that uses laser light as a mean to measure distance towards a target object. These devices works automatically and have the ability to capture huge amount of 3D coordinates for a target object in a very short time that reaches 1 million points per second [25]. In addition to the coordinates of every scanned point, laser scanners alsocollect information about the intensity of the reflected laser light which is useful to obtain and record an image of the scanned object [6].Laser scanners are very useful in collecting huge amount of points which is called "point cloud". ...
... On the other hand, sensors, which do not introduce waves in the environment, called passive sensors. In this latter case, the 3-D acquisition could be achieved for instance by stereo vision or structure from motion [10]. ...
Surface reconstruction of objects using photogrammetry and terrestrial laser scanning systems (TLS) has been a topic for research for many decades, especially for culture heritage data recording. Recently, many advances into these systems are now available in the market, which give the availability of collecting a huge number of geo-referenced 3-D points covering any object surface. Due to speed and efficiency of data acquisition by means of terrestrial laser scanners, researchers and designers can select the reliable technique, depending on their application, that can be complete to give good results for the complex surfaces such as heritage objects. As Grand Egyptian Museum (GEM), located nearby the Giza Pyramids, is set to open by 2020, which considered as the largest museum from its type all over the world, with a huge area covered about a half million m2. GEM is proposed to be a unique museum all over the world for presenting a huge number from old history Egyptian artifacts. Consequently, there is a vital need for building a huge digital database containing complete information for this large number of artifacts. Mobile applications are presently at the primacy of documenting historical and archaeological sites. The current paper examine the methodological framework adopted for one high copy of Pharaonic artifacts, namely Offering Carrier, using hand held laser scanning and convert the results to a mobile application.
... In this sense, although 3D Open Access *Correspondence: juanjose.cubillas@unir.net 5 Dept Tecnologías de La Información Y Comunicación Aplicadas a La Educación, Universidad Internacional de La Rioja, Logroño, Spain Full list of author information is available at the end of the article laser technology was developed during the last half of the twentieth century, it was not until the mid-nineties when they become available to general researches [7]. Ten years ago and due to different reasons, among them the high cost of 3D equipment [8], its systematic use for documentation or surveying archaeological sites was not established. ...
The generation of 3D models through Terrestrial Laser Scanning has proved valuable tools for the study, documentation and recreation of archaeological remains. In this context, it is described how to generate a physical model to provide not only to researchers but also as teaching material for teachers for university students, facilitating their access and study. As a practical case, this article describes the acquisition, processing and management of archaeological data in the archaeological site of Cástulo, Jaén, in South Spain. We expound on how to get the 3D-printed model of the Muslim tower, showing how it is possible to generate a scale and very reliable reproduction of the structure, being also a valuable and tangible material in teaching cultural heritage.
... Laser triangulation (LT) [13] Detection of laser stripes projected onto the object's surface Laser ...
Three-dimensional (3D) shape estimation of the human body has a growing number of applications in medicine, anthropometry, special effects, and many other fields. Therefore, the demand for the high-quality acquisition of a complete and accurate body model is increasing. In this paper, a short survey of current state-of-the-art solutions is provided. One of the most commonly used approaches is the Shape-from-Silhouette (SfS) method. It is capable of the reconstruction of dynamic and challenging-to-capture objects. This paper proposes a novel approach that extends the conventional voxel-based SfS method with silhouette segmentation—segmented Shape from Silhouette (sSfS). It allows the 3D reconstruction of body segments separately, which provides significantly better human body shape estimation results, especially in concave areas. For validation, a dataset representing the human body in 20 complex poses was created and assessed based on the quality metrics in reference to the ground-truth photogrammetric reconstruction. It appeared that the number of invalid reconstruction voxels for the sSfS method was 1.7 times lower than for the state-of-the-art SfS approach. The root-mean-square (RMS) error of the distance to the reference surface was also 1.22 times lower.
... The basic idea was to create as accurate a model as possible of the surface of various objects and buildings. The technology and use of 3D laser scanning took off in the 1990s when the scanners not only became more affordable but also became more accurate, faster, and able to realistically capture the environment [7]. The authors of [8] compared different methods for measuring the volume and deformations of a sand embankment. ...
Determining the displacements and consequent deformations of structures is a demanding branch of engineering. Displacements are most often determined by geodetic methods, among which high-precision non-contact methods have recently taken the lead. Engineering geodesy is an indispensable part of construction projects. In the desire for efficient and fast measurements, the technology of terrestrial laser scanning (TLS) and the use of robotic total station (RTS) and other geodetic methods are becoming more and more useful for engineers. In the presented study, we focused on the measurement and comparison of vertical displacements with various mentioned equipment and the determination of the influence of meteorological conditions on the displacements of timber beams that we used to perform the experiment. Measurements were performed both in the laboratory and outdoors. A novelty in the work was the use of a TLS scanner to determine the evaluation of small value displacements and the analysis of the usability of geodetic measuring equipment. In the Materials and Methods section, we describe the equipment used and the characteristics of the beams. The Results section describes the experimental outcomes, which include the performance of experimental analysis of vertical displacements of timber beams under different meteorological conditions. Altogether, the results consist of geodetic measurements and the processing of measured data. The results of measurements of vertical displacements with a terrestrial laser scanner were compared with the results obtained with a robotic total station were evaluated and compared with the displacements calculated from static analysis and the results of other methods used.
Stability in time of major and important objectives is vital and can be achieved by 3D scanners which follow changes in time with construction, respective of the natural or artificial hydrotechnical dams and the obtaining of 3D data in real time with the possibility of evaluating and making quick decisions. This scientific paper approaches a research topic of great importance and actuality in the field of Civil Engineering, Hydrotechnics, and Geomatics using the 3D scanning technologies for the hydrotechnical arrangements (Topolovăţu Mic, Coșteiu and Sânmartinu Maghiar) and hydroameliorative (Cruceni Pumping Station). In Romania, data collection was carried out for the first time using the mobile scanning technology (MMS), “Backpack” type, namely, Leica Pegasus Backpack. Data collection using terrestrial laser scanning technology (Terrestrial Laser Scanning) was carried out with the Leica C10 equipment. The processing of point clouds was carried out using the Inertial Explorer program, and the processing of point clouds was carried out with the Cyclone program. The collection of ground checkpoints used for checking, correcting, and analyzing point clouds was carried out using the GPS Leica GS08 equipment. Compared with traditional methods using classical measuring instruments, precise data was obtained (with an error of 2–4 cm) through 3D laser scanning technology in a short time and with multiple possibilities of processing and visualizing point clouds.
Goals: Explore and review the provision
of orthoses in the UK, and asses the
effects of sedentarism on the foot
brought on by lockdown events.
Results: It was found that orthoses
provision in the UK is poorly handled
through both public and private
healthcare providers. Sedentary
behaviours may have some effect on the
arch height of the foot.
Conclusion: With working at home
becoming more commonplace, the
human potential for sitting has yet to be
reached. Following from the Covid-19
pandemic, working from home may
become more common place. A
symptom of this would be increased
levels of sedentarism, which may result
in a pool of people in need of highly
personalised and bespoke orthotics. This
report highlights ways in which industry
4.0 technology can improve upon and
streamline current services, such that it
may hope to keep up with the potential
of future demand.
This study focuses on design and development of a 3d scanner using photogrammetry as the principal technique to build hand prostheses. This work also applies generative design principles, manufacturing knowledge and industrial design concepts to optimize the development of the final product in comparison with existing typologies on the market. The construction of this 3d scanner prototype responds to the necessity of facilitate the creation process of hand prostheses. This device takes advantage of the use of cameras to capture information about the hand features. After that, the 3d scanner digitalizes the information, avoiding wasted time on digital modeling or traditional methods to elaborate hand prostheses. This 3d scanner prototype aims to optimize time, development processes and the cost of hand prostheses through the use of rapid prototyping (RP).
Three-dimensional digital models are becoming more affordable especially with the increase in the bandwidth of the Internet and the graphics display ability on the computer screen. Inspection, navigation, virtual museums, cultural heritage digital archiving, animation, and visualizations are some of the important applications for digital models. Unfortunately, there is no single technique able to satisfy all applications requirements, which are mainly the geometric accuracy, photo-realism, automation, portability, and low cost. In the terrestrial range, image based techniques and laser scanning technique are the most common used techniques to capture real objects. Each of them has its points of strength and weakness. While the image based technique has a simple capturing procedure, no points on smooth and textureless surfaces can be recovered. On the contrary, laser scanners can easily capture such surfaces, but the laser ray can not detect their colors. Laser scanning technique can not also define corners or edges directly. Therefore it would be more convenient if the two data sets are combined together to obtain the advantages of both techniques.
In this work, the geometry is mapped on the digital image and presented in a two dimensional environment. The geometry here is attached to the digital image in form of a static matrix. This offers a descriptive view for the scene in addition to an easy way to extract the 3D geometry without any complications. That is why this development might get the potential to be used by persons like decision makers and archeologists. Structural engineers might also get use of it to realize drawings for an existing structure or to check the real dimensions of the structure against its design. On the other hand, mapping the images color/texture on the geometry will result in colored clouds or textured models. The previous attempts to produce such products showed the need for the automation in the data fusion phase. Automatic algorithms has been developed to achieve the desired automation within this thesis.
Heute kann auf eine Vielzahl von Messmethoden und -techniken zugegriffen werden, um geometrische Parameter wie Lage, Größe, Orientierung und Form eines Bauwerkes zu erfassen. Im Zusammenhang mit der Bauaufnahme wird bevorzugt die Messmethodik Handaufmaß angewendet, sehr häufig werden aber auch Verfahren aus der Architekturphotogrammetrie genutzt und seltener kommen tachymetrische Verfahren zum Einsatz. Die Bauaufnahme ist als Umkehrung des Prozesses zu beschreiben, der vom architektonischen Entwurf über die Bauausführung zum fertiggestellten, ggf. im Laufe der Zeit veränderten, Bauwerk führt (Wangerin 1992). Die Bauaufnahme ist somit auf die Analyse und Interpretation der Befunde eines Bauforschenden angewiesen. Zu den wichtigsten Befundquelle gehört neben dem Original-Bauwerk selbst die Beschreibung der Bauwerksgeometrie in Form von Grundrissen, Schnitten und Ansichten, wie sie durch eine der Aufmaßtechniken herzustellen sind. Die maßstabsgetreuen Zeichnungen bilden zudem die Dokumentationsgrundlage für weitere Befunde, die mit anderen Untersuchungsmethoden wie z.B. Ultraschallmessungen oder der Thermographie gewonnen werden können.
Als weitere Alternative zu den konventionellen Messtechniken wurden Mitte der 1990er Jahre terrestrische 3D-Laserscanner entwickelt. Bei einem Laserscanner wird ein Laserstrahl auf die Oberfläche eines Messobjektes gerichtet. Über die Laufzeit oder die Phasenverschiebung des vom Messobjekt zurückgeworfenen Lichtsignals wird die Entfernung bestimmt. Der Laserstrahl wird sehr schnell z.B. über Spiegelsysteme schrittweise in der Horizontalen und Vertikalen abgelenkt. Das Objekt wird so durch Profile flächenhaft erfasst. Als Ergebnis erhält man für jeden Profilpunkt die kartesischen Koordinatenwerte x, y und z. Im Gegensatz zu den konventionellen Messverfahren wird mit einem 3D-Laserscanner das Messobjekt in einem regelmäßigen Raster abgetastet und seine Oberfläche durch eine Wolke von unklassifizierten Punkten beschrieben.
Diese neue Art der Diskretisierung und deren Bedeutung für die Ableitung der Bauwerksgeometrie ist der Ausgangspunkt für diese Arbeit. Die 3D-Laserscanner-Messtechnik erlaubt unter günstigen Bedingungen die Vermessung von Objekten mit einer Ausdehnung bis etwa 50m binnen weniger Minuten. Während einer einzigen Messung wird eine Punktwolke mit etwa einer Million 3D-Punkten erzeugt. Diese im Vergleich mit anderen geodätischen Messverfahren extrem hohe Messgeschwindigkeit stellt ein enormes Kostensenkungspotential dar. Bislang wird dieser Einspareffekt aber fast vollends durch die aufwendige, überwiegend manuell durchzuführende, dreidimensionale Auswertung aufgezehrt.
In dieser Arbeit wird die automatisierte Auswertung von Punktwolken verfolgt. Ergebnis der Auswertung ist ein Randflächenmodell des Bauwerks. Diese Aufgabe ähnelt der Flächenrückführung im Bereich des Reverse-Engineering. Der wesentliche Unterschied zum Reverse-Engineering ist, dass sich die Oberflächengeometrie eines Gebäudes überwiegend aus planaren Flächen zusammensetzt, die sich mehr oder minder im rechten Winkel schneiden, während beim Reverse-Engineering die Modellierung mit ausrundenden Freiformflächen im Vordergrund steht. Vorinformationen über die Art der Objektoberfläche sind beim Reverse-Engineering eher unüblich; bei Bauwerken hingegen wird innerhalb einer gewissen Toleranz die Ebenheit und Vertikalität z.,B. einer Wand vorausgesetzt. Das entwickelte Verfahren erlaubt eine weitgehende automatisierte Bestimmung der Bauwerksgeometrie, wenn diese Besonderheiten beachtet werden. Die neu eingeführte Methodik der getrennten Verarbeitung einzelner Punktwolken mit anschließender Vereinigung der Einzelmodelle ermöglicht den Entwurf relativ einfacher, universeller und geräteunabhängiger Algorithmen, die zudem auch für große Punktmengen geeignet sind. Für die Transformation von Punktwolken in ein gemeinsames Bezugssystem werden verschiedene Verfahren vorgeschlagen und untersucht.
Aufbauend auf der dreidimensionalen Auswertung werden Verfahren zur automatischen Extraktion von Grundrissen und Schnitten sowie zur Berechnung von Orthophotos angegeben, die für absehbare Zeit weiterhin als Endprodukte von anderen Fachdisziplinen gefordert werden. Wird ein 3D-Laserscanner mit einer Digitalkamera derart kombiniert, dass während des Scannens automatisch Farbphotos aufgenommen werden können, so erhält man korrespondierte Bild- und Geometriedaten für das Messobjekt. Diese Arbeit beschreibt ein Verfahren zur Kombination dieser beiden Informationsebenen. Um die Vorteile diese Technik zu verdeutlichen, ist ein Algorithmus entworfen worden, um Panoramen und Orthophotos höchster Qualität z.B. von einer Hausfassade aus den kombinierten Daten abzuleiten. Die Anwendbarkeit und Nützlichkeit der dargelegten Methoden und Verfahren wird mit drei Praxisbeispielen belegt.
The ability of lidar technology to provide three-dimensional elevation maps of the terrain, high precision distance to the ground, and approach velocity can enable safe landing of robotic and manned vehicles with a high degree of precision. Currently, NASAis developing novel lidar sensors aimed at the needs of future planetary landing missions.These lidar sensors are a 3-Dimensional Imaging Flash Lidar, a Doppler Lidar, and a Laser Altimeter. The Flash Lidar is capable of generating elevation maps of theterrain toindicate hazardous features such as rocks, craters, and steep slopes. The elevation maps, which arecollected during the approach phase of a landing vehicle from about 1 km above the ground, can be used to determine the most suitable safe landing site. The Doppler Lidar provides highly accurate ground relative velocity and distance data thusenablingprecision navigation to the landing site. Our Doppler lidar utilizes three laser beams that are pointed indifferent directions to measure line-of-sight velocities and ranges to the ground from altitudes of over 2 km.Starting at altitudes of about 20km and throughout the landing trajectory,the Laser Altimeter can provide very accurate ground relative altitude measurements that are used to improve the vehicle position knowledge obtained from the vehicle'snavigation system. Betweenaltitudesof approximately 15 km and 10 km, either the Laser Altimeter or the Flash Lidar can be used to generate contour maps of the terrain, identifying known surface features such as craters to perform Terrain relative Navigation thus further reducing the vehicle's relative position error. This paper describes the operational capabilities of each lidar sensorand provides a status of their development.
Terrestrial laser scanners (TLSs) are being used more frequently in cultural heritage recording due to their high data acquisition rate, relatively high accuracy and high spatial data density. In terms of measurement accuracy and quality assurance, performance evaluation techniques and tractable calibration procedures for TLSs are still evolving. This paper reports on three sets of experiments designed to evaluate scanner performance. The first set was conducted in a laboratory environment with the aim to quantify measurement precision as a function of different operational parameters such as scan resolution, pulse mode and range accuracy mode. Results indicate scanner precision was independent of resolution and pulse mode, but dependent upon range accuracy mode. In the second set, a cylindrical object was moved in known vertical increments and scanned at each location to empirically quantify scanner sensitivity. Displacement was estimated by comparing surfaces modelled from the scanner data. Displacements of greater than 8 mm were recovered with an RMS accuracy of less than ± 1mm. The third experiment was measurement of a wooden bridge deforming in response to an applied static load. Bridge deformations estimated by precision digital photogrammetry and laser scanning are compared.
The digitalization of real-world objects is of vital importance in various application domains. This method is especially applied in industrial quality assurance to measure the geometric dimension accuracy. Furthermore, geometric models are the very foundation of contemporary three-dimensional computer graphics. In addition to create new models by using a modeling suite, the use of 3D laser scanners has recently become more and more common. To reconstruct objects from laser scan data, usually very large data sets have to be processed. In addition, the generated point clouds usually contain a considerable amount of errors. Therefore, it is necessary to optimize the data for further processing.
Compared to algorithms that interactively manipulate point clouds through an approximation with polygonal meshes, we aim to automatically correct each measurement individually and directly integrate the methods into the measurement process. In addition to traditional methods which usually assume point clouds as unstructured, this work introduces techniques for the extraction of common data structures from optical 3D scanners. Based on this information, procedures are developed to enable automatable procedures of scan data optimization and evaluation. The feasibility of the proposed methods is shown at the example of different real-world objects and industrial applications.
This book provides an introduction to the scope, potential, and limitations of remote sensing. Early chapters describe the basic types of instruments and sensors used in remote sensing: satellite systems, laser and active aircraft systems, ground wave and sky wave techniques, active microwave instruments. Further chapters discuss in detail the question of atmospheric corrections to remotely sensed data, and image processing techniques. Applications of remote sensing to the atmosphere, the geosphere, the hydrosphere, and the general environment are outlined. Three appendices provide a brief bibliography, a source of remotely sensed data, and a list of abbreviations and acronyms. -N.Davey
All instruments collecting 3D coordinates of a given region of an object surface automatically and in a systematic pattern at high rates and achieving these results in near real time are considered as 3D scanning instruments in this article. For cultural heritage documentation, mobile systems for close-and mid-range applications are applicable. Different technical solutions have been developed to obtain the necessary measurements for the derivation of the 3D point coordinates on a reflecting surface. Ranging scanners measure horizontal and vertical angles and compute the distance either by the time-of-flight method or by comparing the phases of the transmitted and received wave form of a modulated signal. Triangulation type instruments include a base. They analyze the location of a projected laser spot or other pattern using one or two CCD cameras. The different principles lead to a different accuracy behavior of the distance measurement. Since noisy measurements are difficult to process, a high accuracy of the scanner is desirable. This leads to the conclusion that no single scanner can fulfil all demands in different cultural heritage recording projects. Besides accuracy considerations, other characteristics are important for the selection of the most suitable instrument for a certain task. Among these are scanning speed and resolution, range limits, influence of interfering radiation, possible field of view, inclusion of imaging cameras, ease of transportation, type of power supply, and the quality of the scanning software. A list of presently available 3D scanners completes the overview given in this article.
Nondestructive measurement of microscale features remains a challenging metrology problem. For example, to assess a high aspect ratio small hole it is currently common to cut a cross section and measure the features of interest using an atomic force microscope, scanning probe microscope, or scanning electron microscope. Typically, these metrology tools may be suitable for surface finish measurement but often lack the capability for dimensional metrology. The aim of this article is to discuss the development of a high aspect-ratio microscale probe for measurement of microscale features. A 700:1 high aspect ratio probe shank is fabricated with a 7 μm diameter, and attached at one end to an oscillator. The oscillator produces a standing wave in the oscillating probe shank as opposed to conventional probes that use a microscale sphere on the end of a comparatively rigid shank. As a result of the standing wave formed in steady state vibration, the free end of the shank generates an amplitude of oscillation greater than the probe shank diameter. Thus, the probe does not require a spherical ball to serve as the contact point and simply uses the contact diameter of the free end of the vibrating shank. This methodology is referred to as a virtual probe tip. The virtual probe tip in conjunction with a nanopositioning scanner is used to measure surface profile measurements over traverse lengths of 130 μm. In this article, results from profiles of a 500 nm step height and a ruby sphere of diameter 1 mm are presented. Experiments in this article indicate the ability to repeatedly resolve surface features of less than 5 nm while maintaining bandwidths greater than 1 kHz. Furthermore, adhesion problems often encountered with micrometer scaled probes were not observed during profile measurements with this virtual probe.
We describe a high-resolution, real-time 3-D shape measure- ment system based on a digital fringe projection and phase-shifting tech- nique. It utilizes a single-chip digital light processing projector to project computer-generated fringe patterns onto the object, and a high-speed CCD camera synchronized with the projector to acquire the fringe im- ages at a frame rate of 120 frames/s. A color CCD camera is also used to capture images for texture mapping. Based on a three-step phase- shifting technique, each frame of the 3-D shape is reconstructed using three consecutive fringe images. Therefore the 3-D data acquisition speed of the system is 40 frames/s. With this system, together with the fast three-step phase-shifting algorithm and parallel processing software we developed, high-resolution, real-time 3-D shape measurement is re- alized at a frame rate of up to 40 frames/s and a resolution of 532 500 points per frame. © 2006 Society of Photo-Optical Instrumentation