3D Scanner在泥沙整体物模型中的应用研究

本文以韩国东部海岸沙滩的防护物理模型为依托,利用3DScanner获取实验地形的三维数据,采用降维数字去燥法和高精度地形演变分析法,快速、准确地对实验地形的三维数据进行去噪、数据网格化以及试验前后高程数据差值,得到整体区域的淤积和冲刷情况。

A voxel-based fine-scale 3D landscape pattern analysis using laser scanner point clouds

The landscape pattern metrics can quantitatively describe the characteristics of landscape pattern and are widely used in various fields of landscape ecology.Due to the lack of vertical information,2D landscape metrics cannot delineate the vertical characteristics of landscape pattern.Based on the point clouds,a high-resolution voxel model and several voxel-based 3D landscape metrics were constructed in this study and 3D metrics calculation results were compared with that of 2D metrics.The results showed that certain quantifying difference exists between 2D and 3D landscape metrics.For landscapes with different components and spatial configurations,significant difference was disclosed between 2D and 3D landscape metrics.3D metrics can better reflect the real spatial structure characteristics of the landscape than 2D metrics.

FARO R推出新版手持式三维激光扫描仪FARO Scanner Freestyle 3D X

近日，FARO推出全新的FARO Scanner Freestyle3D X手持式激光扫描仪，该产品的推出意味着FARO现在能为客户提供两款手持式扫描仪，以帮助客户提高效率、节省时间和更有效地做出基于数据导向的决定。

新版手持式三维激光扫描仪FARO Scanner Freestyle 3D DX

Freestyle 3D X采用最先进的扫描技术。使1m范围内的扫描精度提高到1mm。Freestyle 3D X采用美国国家标准与技术研究院的可追踪校准附件为用户提供可验证的数据精确度，这对取证扫描和其他受到严格监管的行业来说是非常关键的。

3D激光扫描测量开发建设项目堆弃土边坡侵蚀强度的试验研究

为了提高开发建设项目水土保持监测中侵蚀强度测量的效率和精度,尝试使用3D激光扫描仪对排土场堆弃土边坡进行土壤流失量监测,并与常用的测钎法进行比较。结果表明:在同一水土流失坡面同时期的监测中,传统测钎法的监测结果与3D激光扫描法监测的结果偏差为13.26%;3D激光扫描仪具有较高的土壤形态变化记录性能,相对传统的监测方法具有较高的监测精度。

3D Modelling of Biological Systems for Biomimetics

With the advanced development of computer-based enabling technologies, many engineering, medical, biology, chemistry, physics and food science etc have developed to the unprecedented levels, which lead to many research and development interests in various multi-discipline areas. Among them, biomimetics is one of the most promising and attractive branches of study. Biomimetics is a branch of study that uses biological systems as a model to develop synthetic systems. To learn from nature, one of the fundamental issues is to understand the natural systems such animals, insects, plants and human beings etc. The geometrical characterization and representation of natural systems is an important fundamental work for biomimetics research. 3D modeling plays a key role in the geometrical characterization and representation, especially in computer graphical visualization. This paper firstly presents the typical procedure of 3D modelling methods and then reviews the previous work of 3D geometrical modelling techniques and systems developed for industrial, medical and animation applications. Especially the paper discusses the problems associated with the existing techniques and systems when they are applied to 3D modelling of biological systems. Based upon the discussions, the paper proposes some areas of research interests in 3D modelling of biological systems and for Biomimetics.

Focus3D三维激光扫描仪测距精度检校试验

为对地面三维激光扫描仪的测距精度进行校准,以Focus3D三维激光扫描仪为例,对其径向距离和空间距离的测量精度进行了检校试验。采用该型三维激光扫描仪对具有几何中心的球型标靶进行扫描获得试验数据,并利用Geomagic Studio软件对点云数据进行拟合精度评定。试验表明:Focus3D三维激光扫描仪的空间距离测量精度为0.61 mm(≤2 mm),在5~40 m范围内的径向测距精度为-2~2 mm,测距超过50 m后,测量精度呈离散趋势。

FARO推出Freestyle 3D X

2015年9月15日．FARO Technologies，Inc．宣布推出全新的FARO Scanner Freestyle 3D X手持式激光扫捕仪。Freestyle 3D X的推出也意味着FARO现在能为客户提供两款手持式扫描仪。以帮助客户提高效率、节省时间和更有效地做出基于数据导向的决定。

三维激光扫描数据获取高分辨率DTM试验研究

三维激光扫描技术能够提供实体表面点云数据,可用于获取高精度高分辨率数字地形模型。本文以重庆万州区付家岩滑坡体为例探讨了采用三维激光扫描监测技术获取数字地形模型的方法,着重讨论了相关点云数据处理流程和关键技术问题。通过结合差分GPS技术进行激光数据的相对定位和绝对定位、去噪、拼接等方法,获得了该区域地表高精度地形数据,并生成了相应的数字高程模型。试验结果初步说明该技术可用于获取小尺度高精度高分辨率数字地形模型,具有一定的应用前景。

车载LiDAR点云数据分割与半自动化建模方法

针对车载激光雷达(light detection and ranging,LiDAR)点云数据的不完整性问题,提出一种车载LiDAR点云数据分割以及基于分割后点云数据的半自动化建模方法。首先对点云数据进行标准格式转换及稀化;然后以不同地物的属性和几何特征为分割条件,分别建立道路、建筑物、树和路灯等附属设施的三维模型,并利用车载以及航空图像的纹理信息辅助建筑物的立面和顶面三维建模;最后以真实街景为实验区,基于拓普康IP-S2车载LiDAR点云数据,完成该街景的分割与建模。实验结果表明,该文提出的点云数据分割与街景地物重建方法比较简单,可实现道路和建筑物的半自动化分割;利用成熟的建模软件和方法,实现了建模的完整性和较强的可靠性。

Cyra三维激光扫描点云数据在AutoCAD中的处理方法研究

文章详细介绍了Cyra三维激光扫描点云数据在AutoCAD中的处理过程,重点介绍了坐标纠正和进行三维建模方法,总结了AutoCAD在三维建模方面的优点,并针对一些处理中的问题提出了一些解决的方法。

RESEARCH ON LASER RANGE SCANNING AND ITS APPLICATION

In this paper the development of the technology of the laser scanning is summarized.The principles of laser range scanning are introduced.Based on the laser scanning technology and methods,which are investigated by the authors to survey deposit volume,a surveying system is developed and a practical application is performed.It is shown that the laser_scanning technology has obvious advantages such as measurement precision,automation and visualization of observed data in comparison with the traditional methods.As a result,labor intensity is relieved obviously and work efficiency is promoted.

Morphologic changes of simple star dunes during the growth process in Dunhuang,China

Star dune is one typical kind of aeolian geomorphology in global sand seas.It has attracted scholars in various research fields for years because of its unique morphologic features like Egyptian pyramid.The landform pattern of star dune is mainly dominated by factors such as regional wind regime,sand availability,and local topography.Star dunes grow vertically as they accumulate sand brought in from different directions;however,little is known regarding morphologic changes during this process.The stability of star dunes based on quantitative data is another unsolved question due to the limitation in measuring equipment or other factors.And whether the star dune can grow into star sand hills is another scientific problem which needs to be discussed.In this paper,the heightening development process and morphological changes of star dunes were monitored in Mingsha Mountain of Dunhuang with the 3D laser scanner.Results show that the star dunes in Mingsha Mountain were formed by a group of relatively steady winds,which were northwest,northeast and south winds.With the increase of the height of the star dunes,the morphological parameters of the dune,such as the volume and bottom area,did not show regular changes.The surface erosion of both Dune 1 and Dune 2 during the observation period was closely related to the regional wind conditions.During the growth of the star dunes,the overall trend of the dunes was relatively steady and the dune shape maintained its stability although the aspect and slope of the sand dunes changed,indicating that the stability of star dune was not complete and was dynamic.Moreover,the variation range of the dune slope was proportional to the volume change of the dune.

Wind dynamic environment and wind-sand erosion and deposition processes on different surfaces along the Dunhuang–Golmud railway,China

The Dunhuang–Golmud railway passes through different deserts in arid areas,especially drifting-sand desert and sandy-gravel Gobi.The near-surface wind environment and wind-sand transport process vary due to different external factors,such as topography,vegetation,and regional climate,resulting in evident spatial differences in surface erosion and deposition.Consequently,the measures for preventing wind-sand hazards will differ.However,the mechanism and control theory of sand damage remain poorly understood.In this study,we used meteorological observation,three-dimensional(3D)laser scanning,and grain-size analysis to compare and evaluate the spatial distribution of wind conditions,sand erosion and deposition patterns,and grain composition in the drifting-sand desert and sandy-gravel Gobi along the Dunhuang–Golmud railway in China.Results show that the annual mean wind speed,the frequency of sand-driving wind,and the drift potential of sandy-gravel Gobi are higher than those of drifting-sand desert,indicating a greater wind strength in the sandy-gravel Gobi,which exhibits spatial heterogeneity in wind conditions.The major sediment components in sandy-gravel Gobi are very fine sand,fine sand,and medium sand,and that in drifting-sand desert are very fine sand and fine sand.We found that the sediment in the sandy-gravel Gobi is coarser than that in the drifting-sand desert based on mean grain size and sediment component.The spatial distributions of sand erosion and deposition in the sandy-gravel Gobi and drifting-sand desert are consistent,with sand deposition mainly on the west side of the railway and sand erosion on the east side of the railway.The area of sand deposition in the drifting-sand desert accounts for 75.83%of the total area,with a mean deposition thickness of 0.032 m;while the area of sand deposition in the sandy-gravel Gobi accounts for 65.31%of the total area,with a mean deposition thickness of 0.028 m,indicating greater deposition amounts in the drifting-sand desert due to the presence of more fine sediment components.However,the sand deposition is more concentrated with a greater thickness on the embankment and track in the sandy-gravel Gobi and is dispersed with a uniform thickness in the drifting-sand desert.The sand deposition on the track of the sandy-gravel Gobi mainly comes from the east side of the railway.The results of this study are helpful in developing the preventive measures and determining appropriate selection and layout measures for sand control.

Measurements and Terminology of Different Measure Methods

Body measuring is very important for garment sizing and pattern making. In this paper, we study the difference of the landmarks between the traditional method and 3D scanner and we also select the 19 circumference measurements,29 height and length measurements, 18 breadth and depth measurements and 3 other measurements, which are quite important in fashion body measuring, to compare the terminology of them in these two measuring method. 3D scanners seem better than the traditional method on these aspects, which are the number of measurements, speed,privacy and data accuracy, but they are limited on measuring posture. And there is no uniform standard for the scanners and the definitions of the measurements in the scanners are diversified.

3维激光扫描仪定向技术研究

针对3维激光扫描仪无法直接获得目标物表面点的大地坐标的缺点,将全站仪导线测量中的定向技术应用到3维激光扫描仪中;根据扫描技术特点,设计了定向标识;根据定向标识的扫描数据,设计了标识的识别算法,并应用最速下降法进行求解,实现了3维激光扫描仪的定向。

The Effectiveness of Different Methodologies in Gathering Information for Developing BIM Models to Support the Operation and Maintenance of Existing Buildings

Systematic, preventive and corrective maintenance is essential for existing buildings in order to retain their original functionality and appearance and satisfy the needs of the users. Essential input for maintenance is information about buildings. This paper discusses the assessment of the advantages and limitations of using photogrammetry and a low-cost 3D scanner to collect information from existing buildings and create, through integrative software, BIM models as information systems to support the operation and maintenance functions. Also, these methodologies were compared with one another as well as with a manual information survey conducted at a university campus. The main conclusion is that a combination of methods must be used to obtain geometrical information on existing buildings for their operation and maintenance functions, depending on which ones are the most suitable for the case at hand.

The Interventions of Pietro da Cortona in the Crypt of Santa Maria in Via Lata in Rome, Studied through a Morphometric Three-Dimensional Survey

Twenty years after the last archaeological researches and surveys, a new investigation has been carried out on the basement in the church of Santa Maria in Via Lata in Rome. The study has employed three-dimensional surveys with laser scanning methodology and has focused both on archaeological and architectural issues. Indeed, the present layout of the basement derives from a XVII century remodelling of early Christian and medieval spaces planned by Pietro da Cortona. The architect gave a unique setting and composition to the underground spaces, different in shapes and building materials, thanks to the refinement of his baroque language. Though he worked in small spaces with static problems connected to the foundations and to the loads of the church rising above, and with poor lighting and extreme dampness, Pietro da Cortona put skilfully together “modern” elements with ancient or historical pre-existences. The study focuses on Berrettini’s design process through a three-dimensional analysis with CAD systems, starting from the new XVII century fa?ade and from the articulated distribution of routes that led to the intimate underground interiors. Metrical processing gave the possibility to improve the knowledge about room geometry and to confirm the interpretations put forward by major scholars such as Krautheimer and Cavazzi.

A shoe-box-sized 3D laser nanoprinter based on two-step absorption

State-of-the-art commercially available 3D laser micro-and nanoprinters using polymeric photoresists based on two-or multi-photon absorption rely on high-power pico-or femtosecond lasers,leading to fairly large and expensive instruments.Lately,we have introduced photoresists based on two-step absorption instead of two-photon absorption,allowing for the use of small and inexpensive continuous-wave 405 nm wavelength GaN semiconductor laser diodes with light-output powers below 1 mW.Here,using the identical photoresist system and similar laser diodes,we report on the design,construction,and characterization of a 3D laser nanoprinter that fits into a shoe box.This shoe box contains all optical components,namely the mounted laser,the collimation-and beam-shaping optics,a miniature MEMS xy-scanner,a tube lens,the focusing microscope objective lens(NA=1.4,100×magnification),a piezo slip-stick z-stage,the sample holder,a camera monitoring system,LED sample illumination,as well as the miniaturized control electronics employing a microcontroller.We present a gallery of example 3D structures printed with this instrument.We achieve about 100 nm lateral spatial resolution and focus scan speeds of about 1 mm/s.Potentially,our shoe-box-sized system can be made orders of magnitude less expensive than today’s commercial systems.

标准牙冠三维模型的建立及其可操作平台的研究

目的 建立标准牙冠的计算机三维模型以及开发其可操作的软件平台。方法 利用三维激光扫描仪扫描全牙列 2 8颗标准牙冠的石膏模型 ,编写程序对获得的数据进行处理 ,重建各牙冠的三维图形 ,并结合国人牙冠的平均测量数据对其进行调整 ,同时在牙冠表面定义特征区和特征点 ,利用程序对牙冠进行各种变换和调整。结果 扫描仪获取了牙冠数据 ,系统重建了各牙冠的标准三维图形 ,可对牙冠进行各种变换使其产生位移、旋转和整体形变 ,按照各牙冠的解剖特点及正中牙合时的咬合接触定义了特征区 ,特征区可以在空间三个方向上产生指定形变。结论 标准牙冠的三维计算机模型精确可靠 ,其操作平台实现了多种功能 ,为进一步开发打下了基础。