Monitoring of a construction site

Kassel, one of Germanys most dynamic and growing cities, is facing several large construction sites to get ahead of the demanding tasks. Especially the growing need for residential property and industrial estate in and around the cities shapes every planning process the municipality faces. With an approximated construction volume of more than 70 million euro and an area covering 136 hectares, the exploitation of the business park Langes Feld ranks high in the biggest construction projects in the area. Planning to sell the first areas close to the motorway A49, efficient time management was needed. Using Leica Geosystems Unmanned Aerial Vehicle (UAV) solution to get a clear view on the sites progress helped to stay on schedule.

从一开始

To coordinate 40 construction workers and 18 earthmoving machines on site, perfect planning and a steady stream of information is necessary to get a clear view over current tasks. A typical task of surveyors to support the construction management is the providing of precise geo-data and scrutiny of moved masses. Using the collected data, economic and environmental alternatives can be shown to decision makers to increase sustainability and efficiency.

高分辨率数码相机连接到无人机s becoming more and more a credible alternative in surveying and mapping to traditional terrestrial methods. Using photogrammetry, for many a formerly unloved field of education, allows you to take up large areas of interest within a very short span, so it is getting more into the focus of engineers. Highly detailed point clouds, orthophotos and digital elevation models (DEMs) are possible results that can be created with Leica Geosystems UAVs. With additional software solutions, there is even the possibility to create high precise stereophonic pictures.

Airborne support

除了对建筑工地进行调查的传统方式外，使用无人机进行了空降的长期监控。为了支持GEO数据收集中的常规测量服务，特别是为了控制和记录移动的群众，定性和定量证明和库存控制是Leica Geosystems无人机解决方案所做的主要任务。最高的准确性，收集到的数据的快速可用性以及提高安全性与降低成本并进行调查，而不会中断正在进行的工作流程。其他挑战是接收区的植被，机械和工作材料。它们也由UAV传感器技术记录，并且必须在评估过程中进行编辑。

Autonomous flights under steady supervision

由于生成了可比的数据，并且在此期间没有变化，因此使用特殊软件在第一次飞行之前进行飞行计划。使用地图材料和摄像头数据库来提供最佳摄影测量飞行计划，从而支持用户。对施工领域的准确性和成本以及所需的重复记录的要求需要最佳使用可用技术，并遵守标准化工作流程。在进行任何飞行之前，必须测量地面控制点（GCP）以精确调整收集的数据。在UAV上使用具有RTK能力的GNSS接收器来高精度直接对图像数据的直接地理发行，因为该项目意味着将费用减少到最低和清晰的时间节省。在当前情况下，仅使用一个GCP来消除摄像机校准中可能的残余错误。详细的准备工作和带有无人机的标准化工作流程确保了实际航班的时间少。只有两次航班，可以在很短的时间内对15公顷的总建筑项目的部分区域进行调查。带有厘米精确的地理发作的高分辨率照片被送入Agisoft Photoscan进行评估。飞行后仅三个小时内，客户就能以地理参与点云的形式获得飞行结果，以及正观谱以进行进一步评估。 The point clouds were further processed with Leica Infinity office software after the first analysis of the data quality.

Reducing costs by increasing value of the information

By using Leica Geosystems UAV, it was possible to carry out a complete and accurate condition survey of the construction project every week without entering the site and to move around in the potential danger area and disturbing the ongoing processes.

In addition to a complete and 3D documentation of the construction process, the point clouds with 100 points per square metre were also used to document mass movements and to perform an accuracy check of the earthworks carried out by heavy machines. Disturbing vegetation as well as machines and material can be manually removed from the calculation within a short time. High-resolution orthophotos with a resolution up to 1 cm per pixel were used for areas, lengths and batch determinations and represent an excellent overview.

现场的重复记录将进行直到施工结束。有50多个计划的录音或无人机，记录并处理了10,000多张个人照片。仅这些数据将需要Terabyte数据存储。

为官员们提供收集的数据，平滑处理和可用数据的速度，无人机证明自己是在每个施工阶段调查站点的宝贵而重要的技术。