The Use of Terrestrial Laser Scanner for 3D Laser Scanning of Complex Shape Structures an important task for personal safety. Different methods and instruments have been used to evaluate structures for different purposes. In this study, the use of a terrestrial laser scanner for 3D laser scanning of complex shaped structures such as the Buddha statue standing on top of a hill is discussed. Computational fluid dynamics (CFD), commonly used by wind engineering researchers for various wind engineering research purposes, requires a stereolithography (STL) file format to analyze data to stimulate wind flow or to calculate the wind load on structures. Therefore, the generation of STL files from 3D scanned data is also carried out during this study. Finally, steps, tips and recommendations for a successful 3D scanning project plan for a large, complex exterior-type structure are included. Keywords: terrestrial laser scanner; Complex shape structure; Stereolithography; Wind loads; Buddha StatueSay no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get the original essayIntroductionPeople like to build new and distinct structures even if they do not take much interest in proper maintenance of these structures. However, in real life, even the smallest structure requires proper periodic and annual structural maintenance to ensure its safety over time. Calculation of factor of safety and numerical analysis like finite element analysis are some of the popular methods used in structural evaluation. Among them, structural configuration is considered one of the most important topics in the process of structural safety calculation, such as structural deformation or structural defects. Various methods and equipment can be used to determine the configuration of structures. In this research, a medium-range terrestrial laser scanner, Faro Focus 3D X330, is used to record the exterior figure of the Laykyun Sekkya standing Buddha statue. Laykyun Sekkya Standing Buddha Statue is located on Po Khaung Mountain, Khatakan Taung Village, Monywa Town, Sagaing Region, Myanmar. The location of the Buddha statue is shown in Figure 1. This hollow type Buddha statue has a total of 31 stories with an area of 131 feet (39.93 m) and 44 feet (13.41 m) with a floor height of 12 feet (3.66 m). The statue is built using reinforced concrete, steel and fiber in 1996 and completely finished in 2008. According to Wikipedia, the Laykyun Sekkya Standing Buddha Statue is considered the second tallest statue in the world. Three-dimensional laser scanning During the three-dimensional laser scanning process, the laser scanner first sends an infrared laser beam to the center of its rotating mirror. Then, this beam is deflected by the mirror in a vertical rotation. This beam is diffused around the proposed scanned object. Light scattered around the scanned object is reflected back into the scanner after it comes into contact with the proposed object. Finally, a digitized image is obtained. Phase shift technology is used to determine the distance between the proposed scanned object and the scanner. Sentence change means changes in the sentence of a waveform relativeto the usual position. From the rotation of the mirror and the horizontal rotation of the laser scanner, the polar coordinates of δ, α and β which represent the distance, vertical angle and horizontal angle are obtained. After that, these polar coordinates are transformed into Cartesian coordinates for further calculations. Three-dimensional Cartesian coordinate data gives the location of each point. This set of points represents the exterior shape of the scanned object. These points are known as point cloud which is the final result of the three-dimensional laser scanner.Scanner LocationThe three-dimensional laser scanner is located at a distance of 303.742 m from the base edge of the Buddha statue. The scanner locations in this range are divided into three different groups which are classified as top viewpoint, central viewpoint, and base viewpoint. The view from above aims to capture the head and shoulder parts of the Buddha statue. The middle viewpoint plans to capture the body parts of the Buddha statue. The basic point of view aims to capture the basic parts of the Buddha statue, such as the leg, foot and stage. Therefore, a total of 36 viewpoints, including 11 top viewpoints, 14 middle viewpoints, and 11 base viewpoints, were used to scan the outer figure of the standing Buddha statue. The locations of these viewpoints are shown approximately in Figure 3. Two viewpoints are removed due to high obstacles. Setting and analysis parameters play an important role in obtaining a good analysis. Good scanning provides an accurate point cloud that can generate an exact STL of the scanned object. Point cloud data may produce errors if the 3D laser scanner is located far from the scanned object. During on-site measurements for this study, a resolution of ½, quality of 3x, range of 303.742 m and color scanning were used. Four types of sensors such as global positioning system, compass, inclinometer and altimeter were also used. A target-free analysis is performed. Accordingly, an externally modified profile at long distances is used to capture the three-dimensional exterior figure of the Laykyun Setkkar standing Buddha statue. ParameterScanner speed 976,000 points/secMeasuring range 330 mPossible error 2 mm at 25 m from the scannerHorizontal field of view 360°Vertical field of view 330˚Weather conditionsRain and dirt produce noise during scans. Additionally, high temperatures have a negative impact on the laser scanning process. The recommended loading temperature of the laser scanner is between 10˚C (50˚F) and 30˚C (86˚F). The recommended operating temperature of the laser scanner is between 5˚C (41˚F) and 40˚C (104˚F). As a result, the analysis schedule is entirely dependent on the weather conditions of the selected analysis area. Monywa is famous for its very high temperature as it enjoys a hot semi-arid climate. According to the Myanmar Times published on May 17, 2010, Monywa recorded a record high temperature of 45.8°C (114.4°F) on May 13, 2010. Therefore, the month of August is chosen to conduct laser scanning on site because the first monsoon months, from April to July, are extremely hot. Between August 6 and 8, Monywa is partly cloudy, with no dirt and light rain with a temperature between 27.8 °C (82 °F) and 37.8 °C (100 °F).Cloud Boost Scan DataPoint which contains a set of points with location coordinates are transferred into SCENE. Then processing the scan, saving, generating high-quality data and exporting itin STL format are made. Faro SCENE is commercial software designed for Faro Focus Scanner and can evaluate scan data captured in a virtual reality (VR) environment. Import First, the draft scans containing the location coordinates of the Buddha statue are imported. Project scanned image from viewpoint number 0. ProcessingProcessing of each scan for a total of 34 scans is carried out. Three-dimensional coordinate data from 360-degree panoramic scans is divided and sorted for each scan. Typically, high-quality color image data and scan point clouds are generated from the scanned draft image. Additionally, filters such as dark scan point filter and distance filter are applied. The dark scan point filter removes scan points by adjusting the reflectance threshold. This filter is necessary because dark surfaces only reflect a small amount of light and these reflections decrease the accuracy of the scan points. The distance filter removes unnecessary points that are outside the specified distance range to avoid overlapping analysis points in exterior analyses. Registration Registration aligns the coordinate system of the 34 scans into a global coordinate system using common reference planes between each scan. During this study, a combination of automatic recording and manual recording is performed. This is achieved by combining images from targetless three-dimensional laser scanning. Sensor data is also used during recording to improve the accuracy of each point. At first, the scans are divided into four groups such as front, back, right and left groups. After that, automatic recording is performed under top base and cloud to cloud recording mode. Then, manual registration is performed by manually selecting common points and planes between each scan. An error of 23.4 mm is present during this laser measurement. Export to STL format A project point cloud for the entire Buddha statue is created after successful saving. Some duplicate points are removed when creating the project point cloud. Next, the project point cloud is meshed into a maximum of 40,000,000 triangles. Once the mesh is successfully completed, it is ready to transform into STL format. Finally, the STL file is produced from the project point cloud data. FinalizationFinalization is done using FreeCAD software. Since the black surface is difficult to capture with a three-dimensional laser scanner, FreeCAD software is used to manually draw the hair part of the Buddha statue because its color is black. First, the SCENE output STL file is imported into FreeCAD. Then its normals are harmonized in a single direction as much as possible. After refining this, it is ready to add a new hair. Refining the shape will also clean up any residual points or edges from the original STL file. Finally, a fully detailed drawn exterior figure of the Laykyun Sekkya standing Buddha statue is successfully obtained. ConclusionsFaro Focus 3D X330 cannot scan an object and only works on line of sight. The selected scanner location should not have any large or huge obstacles. Therefore, when we locate the scanner position, we need to check whether any obstruction on the selected position may affect the configuration of the target structure during the registration process. Otherwise, these can.

Essay / The Use of Terrestrial Laser Scanner for 3D Laser Scanning of Complex Shape Structures an important task for personal safety. Different methods and instruments have been used to evaluate structures for different purposes. In this study, the use of a terrestrial laser scanner for 3D laser scanning of complex shaped structures such as the Buddha statue standing on top of a hill is discussed. Computational fluid dynamics (CFD), commonly used by wind engineering researchers for various wind engineering research purposes, requires a stereolithography (STL) file format to analyze data to stimulate wind flow or to calculate the wind load on structures. Therefore, the generation of STL files from 3D scanned data is also carried out during this study. Finally, steps, tips and recommendations for a successful 3D scanning project plan for a large, complex exterior-type structure are included. Keywords: terrestrial laser scanner; Complex shape structure; Stereolithography; Wind loads; Buddha StatueSay no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get the original essayIntroductionPeople like to build new and distinct structures even if they do not take much interest in proper maintenance of these structures. However, in real life, even the smallest structure requires proper periodic and annual structural maintenance to ensure its safety over time. Calculation of factor of safety and numerical analysis like finite element analysis are some of the popular methods used in structural evaluation. Among them, structural configuration is considered one of the most important topics in the process of structural safety calculation, such as structural deformation or structural defects. Various methods and equipment can be used to determine the configuration of structures. In this research, a medium-range terrestrial laser scanner, Faro Focus 3D X330, is used to record the exterior figure of the Laykyun Sekkya standing Buddha statue. Laykyun Sekkya Standing Buddha Statue is located on Po Khaung Mountain, Khatakan Taung Village, Monywa Town, Sagaing Region, Myanmar. The location of the Buddha statue is shown in Figure 1. This hollow type Buddha statue has a total of 31 stories with an area of 131 feet (39.93 m) and 44 feet (13.41 m) with a floor height of 12 feet (3.66 m). The statue is built using reinforced concrete, steel and fiber in 1996 and completely finished in 2008. According to Wikipedia, the Laykyun Sekkya Standing Buddha Statue is considered the second tallest statue in the world. Three-dimensional laser scanning During the three-dimensional laser scanning process, the laser scanner first sends an infrared laser beam to the center of its rotating mirror. Then, this beam is deflected by the mirror in a vertical rotation. This beam is diffused around the proposed scanned object. Light scattered around the scanned object is reflected back into the scanner after it comes into contact with the proposed object. Finally, a digitized image is obtained. Phase shift technology is used to determine the distance between the proposed scanned object and the scanner. Sentence change means changes in the sentence of a waveform relativeto the usual position. From the rotation of the mirror and the horizontal rotation of the laser scanner, the polar coordinates of δ, α and β which represent the distance, vertical angle and horizontal angle are obtained. After that, these polar coordinates are transformed into Cartesian coordinates for further calculations. Three-dimensional Cartesian coordinate data gives the location of each point. This set of points represents the exterior shape of the scanned object. These points are known as point cloud which is the final result of the three-dimensional laser scanner.Scanner LocationThe three-dimensional laser scanner is located at a distance of 303.742 m from the base edge of the Buddha statue. The scanner locations in this range are divided into three different groups which are classified as top viewpoint, central viewpoint, and base viewpoint. The view from above aims to capture the head and shoulder parts of the Buddha statue. The middle viewpoint plans to capture the body parts of the Buddha statue. The basic point of view aims to capture the basic parts of the Buddha statue, such as the leg, foot and stage. Therefore, a total of 36 viewpoints, including 11 top viewpoints, 14 middle viewpoints, and 11 base viewpoints, were used to scan the outer figure of the standing Buddha statue. The locations of these viewpoints are shown approximately in Figure 3. Two viewpoints are removed due to high obstacles. Setting and analysis parameters play an important role in obtaining a good analysis. Good scanning provides an accurate point cloud that can generate an exact STL of the scanned object. Point cloud data may produce errors if the 3D laser scanner is located far from the scanned object. During on-site measurements for this study, a resolution of ½, quality of 3x, range of 303.742 m and color scanning were used. Four types of sensors such as global positioning system, compass, inclinometer and altimeter were also used. A target-free analysis is performed. Accordingly, an externally modified profile at long distances is used to capture the three-dimensional exterior figure of the Laykyun Setkkar standing Buddha statue. ParameterScanner speed 976,000 points/secMeasuring range 330 mPossible error 2 mm at 25 m from the scannerHorizontal field of view 360°Vertical field of view 330˚Weather conditionsRain and dirt produce noise during scans. Additionally, high temperatures have a negative impact on the laser scanning process. The recommended loading temperature of the laser scanner is between 10˚C (50˚F) and 30˚C (86˚F). The recommended operating temperature of the laser scanner is between 5˚C (41˚F) and 40˚C (104˚F). As a result, the analysis schedule is entirely dependent on the weather conditions of the selected analysis area. Monywa is famous for its very high temperature as it enjoys a hot semi-arid climate. According to the Myanmar Times published on May 17, 2010, Monywa recorded a record high temperature of 45.8°C (114.4°F) on May 13, 2010. Therefore, the month of August is chosen to conduct laser scanning on site because the first monsoon months, from April to July, are extremely hot. Between August 6 and 8, Monywa is partly cloudy, with no dirt and light rain with a temperature between 27.8 °C (82 °F) and 37.8 °C (100 °F).Cloud Boost Scan DataPoint which contains a set of points with location coordinates are transferred into SCENE. Then processing the scan, saving, generating high-quality data and exporting itin STL format are made. Faro SCENE is commercial software designed for Faro Focus Scanner and can evaluate scan data captured in a virtual reality (VR) environment. Import First, the draft scans containing the location coordinates of the Buddha statue are imported. Project scanned image from viewpoint number 0. ProcessingProcessing of each scan for a total of 34 scans is carried out. Three-dimensional coordinate data from 360-degree panoramic scans is divided and sorted for each scan. Typically, high-quality color image data and scan point clouds are generated from the scanned draft image. Additionally, filters such as dark scan point filter and distance filter are applied. The dark scan point filter removes scan points by adjusting the reflectance threshold. This filter is necessary because dark surfaces only reflect a small amount of light and these reflections decrease the accuracy of the scan points. The distance filter removes unnecessary points that are outside the specified distance range to avoid overlapping analysis points in exterior analyses. Registration Registration aligns the coordinate system of the 34 scans into a global coordinate system using common reference planes between each scan. During this study, a combination of automatic recording and manual recording is performed. This is achieved by combining images from targetless three-dimensional laser scanning. Sensor data is also used during recording to improve the accuracy of each point. At first, the scans are divided into four groups such as front, back, right and left groups. After that, automatic recording is performed under top base and cloud to cloud recording mode. Then, manual registration is performed by manually selecting common points and planes between each scan. An error of 23.4 mm is present during this laser measurement. Export to STL format A project point cloud for the entire Buddha statue is created after successful saving. Some duplicate points are removed when creating the project point cloud. Next, the project point cloud is meshed into a maximum of 40,000,000 triangles. Once the mesh is successfully completed, it is ready to transform into STL format. Finally, the STL file is produced from the project point cloud data. FinalizationFinalization is done using FreeCAD software. Since the black surface is difficult to capture with a three-dimensional laser scanner, FreeCAD software is used to manually draw the hair part of the Buddha statue because its color is black. First, the SCENE output STL file is imported into FreeCAD. Then its normals are harmonized in a single direction as much as possible. After refining this, it is ready to add a new hair. Refining the shape will also clean up any residual points or edges from the original STL file. Finally, a fully detailed drawn exterior figure of the Laykyun Sekkya standing Buddha statue is successfully obtained. ConclusionsFaro Focus 3D X330 cannot scan an object and only works on line of sight. The selected scanner location should not have any large or huge obstacles. Therefore, when we locate the scanner position, we need to check whether any obstruction on the selected position may affect the configuration of the target structure during the registration process. Otherwise, these can.

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