Recently, after receiving the takeoff order, the surveyor of a surveying and mapping center skillfully started the UAV remote control task button, and the UAV took off smoothly, preparing to collect data on the beach situation in the survey area within the jurisdiction, less than 2 hours, the image information and terrain coordinate data of the surrounding 5 kilometers are collected.
The surveying and mapping center is responsible for surveying and mapping tasks within the jurisdiction of 140 kilometers. In the past, to carry out comprehensive topographic observation of dry water in the jurisdiction, the surveyor could only carry heavy measuring equipment and materials one by one, step by step to carry out on-the-spot measurement of the material information in the mainland of the survey area, and after summarizing and sorting out, it is reflected in the drawing in the form of data, but the visual image data of the test area cannot be obtained. At the same time, the measurement environment is dangerous, the water level is low in dry season, and it is light to step on the mud. What is more dangerous is that the Moor is often exposed, and the surface looks flat. If you step on it, you will be trapped in it.
How can we not only avoid personal safety risks, but also improve the measurement efficiency? After repeated investigation and demonstration, the surveying and mapping center decided to use UAV technology to carry out comprehensive topographic observation in dry season. Through aerial photogrammetry, high-definition digital images can be directly obtained, which more intuitively reflects the whole picture of the coastline, beach, and renovation buildings of the test area, and clearly and vividly presents the overall features of the test area, greatly reduce manpower and material resources, overcome the adverse effects of harsh environment, and complete topographic data collection with high efficiency and quality.
It is understood that the surveying and mapping center adopts multi-rotor unmanned aerial vehicles, which have centimeter-level navigation and positioning systems and high-performance imaging systems, and can reach the absolute accuracy of 5cm plane mapping at a height of 100 meters vertically, at the same time, the object information can be collected from multiple angles to generate a high-precision three-dimensional model. Finally, surveying and mapping personnel then load and generate orthographic images and vertical photographic models through image post-processing software to extract elevation points to realize the rendering of waterway map terrain.