扫描直到你下降

When an international retail group approached the Australian surveying firm, Project Surveyors, about creating a survey-accurate architectural and structural Revit model for the country’s second largest shopping centre, the firm was excited to participate. When the deadline was set for only 90 days later, Project Surveyors knew while future centre customers may shop till they dropped, the firm’s seven qualified laser scanning surveyors would be doing the same with 3D laser scanning.

The Sydney shopping centre is currently undergoing redevelopment, and the client needed a fully-parametric Revit Building Information Modelling (BIM) model for architects, engineers and facility managers to accurately plan the work needed. Covering a space of 375,000 square metres with vari-ous dimensional obstacles, such as cascading floors, topographic level changes and add-on buildings of diverse sizes, Project Surveyors faced one of its most complex jobs in its 43-year history.

“The enormity and complicated aspects to the building meant that our surveyors had to be meticulous when documenting scan positions and on field notes to assist in the registration of scans,” said Andy Jackson, Project Surveyors’ BIM Spatial manager. “With our Leica Geosystems instruments and soft-ware, we could ensure this.”

扫描，自信建模
项目测量师使用各种Leica Geosystems解决方案来捕获，建模和分析数据。从Leica扫描C10和P20开始，测量师能够捕获细节。由于其远程功能，Leica扫描仪C10用于外墙和内部用于大型结构，例如停车场。内部，使用Leica ScanStation P20用于低分辨率以低分辨率生产快速可靠数据的质量。

杰克逊说：“ P20的快速扫描时间帮助我们改善了现场工作流程，增加了每天四倍的扫描数量。”

For survey control, Project Surveyors used the Leica TS15 and Leica MultiStation MS50. The Multi-Station was also used to scan windows for simpler capturing. Establishing a survey control network around the perimeter of the site and throughout the shopping centre at each level, these instruments ensured millimetre precision for aligning scans of the retrofitting construction. Laser scan targets were coordinated within the control network to maintain the accuracy of the overall point clouds.

从现场55天开始，总共有3,700次扫描。使用Leica Cyclone 9.0清洁并注册了这些扫描中的点云。由于软件中添加了自动对准注册，整个过程仅需20天。与点云到点云的视觉对齐相比，每次大约需要两分钟才能在视觉上找到共同点，自动对准仅需30秒至一分钟。

杰克逊说：“几次扫描听起来并不多，但是当我们谈论成千上万的扫描时，这将成为大量的时间。”“通过这些节省，我们能够将生产率提高至少50％。”

The firm also used Leica TruView to provide the architects with the point cloud data so they could overlay in the model and have extra information, such as dimensions they needed to extract for accu-rate and realistic planning.

“Leica Truview images were a deliverable for the client, but they also helped the modeller to have a complete understanding of what they are modelling over,” said Jackson.

Autodesk Revit 2014用于建模建筑元素，而Autodesk Revit机械，电气，管道（MEP）用于创建管道，植物，管道和其他服务，以创建负载码头的部分MEP模型。由于该项目的规模和细节将花费一个模型120天才能完成，因此，项目测量师与一个建模者团队合作，在一个有线和大型数据网络上合作，在一个中央模型上合作。

Using the export option in Leica Cyclone 9.0, the surveyors exported the point clouds either separately as binary ptg files or unified as pts files. Autodesk Recap was then used to convert the files into Autodesk-compatible rcs files, which could then be inserted into Revit and modelled over. Using Leica Cloudwork for Revit, Jackson added that the exportation and conversion steps of the workflow would be eliminated, providing modellers with point cloud conversion tools as well as a single master data source rather than multiple files and versions of files to deal with.

“Using this laser scanning technology, we have won similar large projects, such as one in Sydney where we’re working with the same consultants who used this model as an example to the project owner of what they required as survey information,” said Scott Deveridge, Project Surveyors director. “Referrals to provide a similar service on another challenging project is the best feedback we can get.”

从HXGN Live中学到的教训
在该项目开始之前的几个月前，随着在拉斯维加斯参加HXGN Live 2014，就发现了购物中心项目是一个宝贵的机会，可以在国际会议和实践展览会上学习一些教训。使用这些新想法，该公司经营大约节省了75％的时间。

Using scan-to-scan registration and auto alignment, the firm decreased its dependence on targets for every scan. The surveyors also used a lower resolution, kept the scanner operating between setups, and created a wheeled-transport tripod to relocate the scanner faster.

“Whereas before we were only able to collect about 16 scans per day, using what we learned from HxGN LIVE, we can now collect anywhere between 60 to 80 scans per day,” said Jackson. “We are also registering about 30 scans per hour, twice as much as before. This translates into significant efficiency gains, and therefore cost savings, for us.”

回到HxGN住在拉斯维加斯,2015项目ect took top honors in the annual Leica Geosys-tems High-Definition Surveying (HDS) Plan Contest. A panel of 11 qualified judges evaluated 24 en-tries based on the completeness and usefulness of the plans, the creative use of point clouds and models, and overall appearance. Project Surveyors took first place with the project in the Build-ings/Heritage category.

杰克逊说：“我们的团队一直在努力工作，我们一直在寻找创新的方法来改善我们的业务。”“赢得这个奖项证实了我们对专业的承诺以及我们对客户的奉献精神。”

A prime example
Another aspect of the Sydney shopping centre project is the innovative use of HDS in BIM. Through the use of a variety of HDS techniques in the field and in the office, Project Surveyors was able to organise and collaborate building information across an accessible platform.

杰克逊说：“在BIM中使用激光扫描有助于我们完全了解已经存在的工作，需要做什么以及建筑过程的情况如何。”“在BIM中使用激光扫描使我们能够为客户提供增值的可交付成果。”

This project is an ideal demonstration of making the real digital world. As HDS captures the most current and accurate situation, professionals can then implement that data into software programs, such as Leica Cyclone or Autodesk Recap, to produce the realistic workable models. Exact adaptions can then be made so that when work is carried out on site, intelligent information is clear and error-free.

“ HDS的技术提供了在几分钟内准确和确定的数字资产准确和确定的数字资产所需的工具和工作流程。”Leica Geosystems HDS副总裁兼业务发展经理Faheem Khan说。“能够为所有利益相关者捕获，管理和交付信息和知识的基础，以提供我们的策略，以提供最快，最清洁，最可靠的硬件以及为所有项目规模，学科和用户扩展的软件投资组合。”