通过移动地图技术保护荷兰免受洪水的侵害

Author:Arno Kijzerwaard

荷兰59%的领土是脆弱性rable to floods and 26 per cent is below sea level. For this Western European country, preventing and protecting against sea water level rise is of vital importance – at the North Sea flood in 1953, the Netherlands testified how important strengthening costal defences is. Due to its low and flat geography, the country contains a large extension of dikes – 17,691 kilometres to be precise.

Dikes in the country are managed by waterboards. The area in the middle of the Netherlands with the Maas, Waal and Nederrijn rivers is beautiful yet vulnerable – due to climate change the sea level is rising causing rivers to flood. To ensure citizens are safe, dikes in this area are checked every two years and completely surveyed every six years to make sure they stay high and firm enough.

Kempkes Landmeten，一家专门翻译广泛的Geodesy中数据的公司，沿着瓦尔河（Waal River）进行了19公里的堤防, in the area of Waterboard Rivierenland. To give an idea of scale, this is 10% of the width of the Netherlands. In the past, dikes were surveyed with traditional survey methods involving a great deal of levelling. Over time, airborne methods, such as laser scanning from a helicopter were applied. Even when surveying from the air is far more efficient than traditional surveying, several rules, accuracies and safety measures must be applied.

选择下一代移动映射

Kempkes Landmeten discussed with Waterboard Rivierenland a new method to survey the safety of the dike. They proposed to use next-generation mobile mapping technology, theLeica Pegasus：两个移动传感器平台，以所需的质量交付任务。

整个区域的传统调查将花费数月才能完成 -两天内完成了19公里的轨迹移动映射解决方案安装在普通汽车上，从道路上扫描。使用Pegasus：两辆在不同的车辆上进行越野调查，然后在几天内扫描了整个项目。这包括双运行，处理移动映射数据并生成结果。现在，传统的测量师只需要在无法通过移动映射捕获的数据中捕获点云和“孔”。

For this project the flexibility of the Pegasus:Two was used to the max. The compact mobile mapping solution was used on a car and quad to reach off-road locations where a normal car would get stuck.

“ Leica Pegasus：两个可以安装在汽车，船上或其他任何其他车辆上。从车辆迁移时，不必重新校准该系统，我们可以灵活，轻松地捕获毫米范围内的现实，”Kempkes Landmeten的所有者Rob Kempkes说。“由于调查更快，不需要采取安全措施，因此可以节省大量费用。”

“我很高兴从事这个项目。我们过去经常进行传统调查的地方，测量师现在可以用四轮驱动越野。他们当然喜欢这个，”负责发展的埃尔温·佩里克（Erwin Perik）说。“整个工作流程非常有效。我们捕获的内容立即被检查了 - 我们从未在不知道数据很好的情况下离开网站。”

从数据到数字地形模型

使用Pegasus：为该项目获取了两个包含点云数据和照片的千兆字节。数据使用Leica Pegasus：AUTOP软件处理，通过多通途检查质量。这意味着轨迹与飞马绘制了两次：两个安装在扫描仪旋转的汽车上。这项双重运行可检查位置质量，并减少数据中的盲点和不必要的流量。所得的彩色点云与50个地面控制点和天然基准点有关。

为了调整和执行质量控制数据，通过Leica Pegasus检查了绝对位置，高度，完整性，传播和着​​色的数据：查看器和Kempkes Landmeten的自制软件。独立的调查方法（例如级别和测量概况）用于双重研究质量。

扫描未覆盖的少数部分，例如建筑物的背面或排水管等物体，使用Leica Total Station和GNSS接收器对传统方法进行了调查。bob apple如果在Pegasus的照片上看不到：两个。

然后，使用传统调查的后处理数据用于为客户生成最终产品 - 一个GIS Metadata完整的3D数字地形模型。

Besides the end result that was mandatory for the assignment, Waterboard Rivierenland is now also able to use all extra gathered data, like the 360-degrees sphere photos collected with the Pegasus:Two. Thanks to the amazing source of extra information, there is no need to go outside. Where in the past the surveyor had to go back into the field, an extra cross profile can be easily generated on a location. This is quicker, safer and a perfect basis to make easier and better-informed decisions in daily processes.

Daring to disrupt

“下一代移动映射适合Kempkes Landmeten。双腿牢固地在粘土中，我们是应用创新技术的先驱，”said Kempkes.“当我们做某事时，它必须是当前的，可靠的和完整的。”

Using the Pegasus:Two has proven to be more flexible, safe, faster and scalable giving Kempkes Landmeten a key advantage over the competition on this and other projects. Investments in new reality capture and processing solutions, just like Leica BLK360 imaging laser scanner and Jetstream, make sharing point cloud data even more efficient.