如何测量一个岛屿

2003年，有远见的本·卡西拉（Ben Kacyra）建立了西克with his idea to create a free and digital archive of cultural heritage sites and architecture to preserve them from natural or human destruction. Driven by the demolition of the Bamiyan Buddhas in 2001 in Afghanistan, Kacyra pursued the idea to save as many cultural heritages as possible at least as a 3D blueprint for following generations. By having Ken Mooyman, Leica Geosystems executive vice president, on CyArk’s Board of Directions, the foundation has another expert and visionary on its side when it comes to mapping and surveying.

Cyark凭借其在3D激光扫描中的知识和专业知识以创建高分辨率的云层，将文化遗产遗址的测量和映射带到了另一个层次。在短时间内，基金会形成了一个全球网络，以在其档案中添加130多个项目，并于2013年10月启动其雄心勃勃西克500 Challenge在五年内扫描和数字保存500个世界遗产。由500咨询委员会was the tidal island St Michaels Mount in Cornwall, England.

的小岛离海岸366米的撒谎south-west of Great Britain, only reachable by boat or, at a low tide, via a causeway, is as well a postcard picture as a historical scene. First populated from circa 4,000 to 2,500 BC, it became a monastery during the 12^thcentury and rose to the now known settlement and pilgrimage site during the 18th century. Endangered due to climate change and erosion, the500咨询委员会suggested St Michaels Mount as a cultural heritage site that should be preserved digitally for further generations.

Time savings with an UAV

为了绘制这个岛，Atlantic GeomaticsandLeica GeosystemsUKpaired up to survey the island and the small village within three days using state-of -the-art technology and a trend-setting workflow involving an Unmanned Aerial Vehicle (UAV). With the technology and on-field knowledge ofLeica GeosystemsUK，映射和调查的专业知识Atlantic Geomatics，以及使用无人机创建精确空中的新方法，完全增强的工作流程进化，改变了测量和绘制大面积的游戏。

The choice to use the autonomous hexacopter to survey a cultural heritage site seemed like a long shot, but the versatile UAV had proven before to be the right pick for preserving structures. In 2014, Leica Geosystems UAVs created detailed 3D models of the library and stadium of the National Autonomous University of Mexico (UNAM).

2016年5月，由10名测量师和飞行员组成的船员前往康沃尔郡海岸，开始保存圣米卡尔斯山（St Michaels Mount）的0.23平方公里（0.09平方英里）。专业人士需要高端设备来完成这项任务。除了Leica GS16 GNS以提高其GPS的准确性外，Leica MS60多站还履行了其在岛上工作期间最高300米的3D网格创建3D网格的承诺。此外，Leica ScanStation P40的范围精度为1.2 mm + 10 ppm，3D位置精度在50米处的3D位置精度为3 mm，以创建文化遗产位置的完全纹理的3D模型。凭借这种出色的准确性和精确度，这两种工具都是Leica Geosystems UAV解决方案的完美补充，该解决方案测量了岛上的空中，以创建高度准确的矫正器。

Streamlining the workflow

在岛上设置65个地面控制点，以捕获尽可能多的细节，工作人员开始为使用MS60多稳态以及GS16 GNSS进行测量准备。但是，面对崎terrain的地形，大胆的悬崖和大西洋潮的挑战，无人机的使用完善了专业人士的工作。将重型设备沿陡峭台阶载重的工程师非常耗时，这是一个主要的安全风险。在安全性和效率方面，使用Leica Geosystems Hexacopter获取详细的图像和无法访问的基础数据是一个相当大的优势。

With a flight altitude of 120 m above sea level, the UAV created precise data from the shorelines to the top of St Michaels Mount within 12 automated waypoint flights. By using the RTK/GNSS – module, the UAV flew with an accuracy of 1-3 cm calculating its precise position out of the data stream from 10 satellites. To get as many details as possible during the flight, the crew mounted the fully integrated Sony Alpha 7R to the hexacopters gimbal. A resolution of 7,360x4,192 pixels (36.4 megapixels) assured that every detail was captured and due to its full-frame Exmor CMOS-sensor an even higher quality was possible and less image noise was distributed. Recording the GPS-data per millisecond, every image taken can be precisely located. With the shutter speed set to 1/1000sec and the aperture to 3.2f, the mounted camera took at an ISO of 800 the pictures without any blur or distortion.

Having the most elaborated software built into Leica Geosystems UAV, the copter tags precise to the millisecond when and where a high resolution picture was taken. This gives you the advantage to match every taken image to the most precise GPS-position in the postprocessing.

By using an UAV and latest equipment, the overall time for surveying was reduced by 60 per cent compared with the standard conventional workflow without aerial support.

当地面团队准备了其测量地点时，空中螺钉为其挑战的挑战设定了无人机。借助内部开发的飞行计划，机组人员为以下航班编程了参数，以便除了传统结果外，六角器还可以收集航空信息。

Capturing more with less

经过三天的飞行，有12架自动航班以捕获岛上的每个细节，以及4,120张拍摄的图片，船员聚集在一起，将数据合并到后加工软件中，以创建圣迈克尔山的数字高分辨率复制品。结果是该岛及其建筑物的3D纹理模型，其中包含超过2.4 GB的高分辨率数据，显示了文化遗产的详细见解。在进一步数据处理中，所有扫描设备中捕获的数据的组合与1-2-3一样容易。地面采样距离（GSD）为3.2 cm，平均位置的相对精度为1.2 cm，在基于云的硬性和基于云的硬性和基于云的硬性硬化的支持下，将无人机数据生成点云和数字高程模型（DEM）软件解决方案。得益于CapturingReality，Agisoft Photoscan Pro，Autodesk Recap和Pix4D等软件，基于地面的扫描数据和空中图像的组合仅需几个小时而不是几天和几周。

Expanding your ways to work on large-scale projects by integrating the flying tripod from Leica Geosystems gives you the ability to create more data, more precisely in less time. But being more than twice as efficient as before is just a nice treat compared to measuring unreachable areas easily and increasing the safety and accuracy of your staff. Leica Geosystems UAV solution is the real deal when you rethink mapping and surveying.