VOLUMETRIC MONITORING OF SANITARY LANDFILLS USING RPA (REMOTELY PILOTES AIRCRAFT) TECHNOLOGY
Landfill, Photogrammetry, Surveillance, Voumetry
The use of photogrammetric techniques, combined with geoprocessing tools and methodologies, allows a temporal analysis of a given land surface area, highlighting the agility in obtaining data, the reliability and the low cost of these techniques. The use of Remotely Piloted Aircraft (RPA) technology enables high spatial and temporal resolution. Aerial images with such qualities contribute to obtaining information in the field, generating data that can be used to support decision making. The objective of this project is the development of a methodology for the volumetric monitoring of landfills using, as a data collection tool, RPA technology. To this end, with the help of the Google Earth software, the area to be surveyed was evaluated in order to identify possible complications to the RPA survey. In this same software, the coordinates of the central point of the study area for flight request were obtained from the Department of Control and Airspace. GNSS (Global Navigation Satellite System) equipment with RTK (Real Time Kinematic) technology was used. Photoidentifiable control and validation points were distributed evenly across the study area. The collected GNSS data were processed in specific equipment software and will use as a reference a point collected and processed using the Precise Point Positioning (PPP) method. The acquisition of the images took place through supervised flight according to the guidelines of the current legislation. The mobile software, PIX4D Capture was used for the development of collection missions, as well as for monitoring the flight plan and configuration of the RPA. The collected images were processed in the PIX4D Mapper software to calculate the positions and orientations of the images automatically, through aerial triangulation (AAT) and Bundle Block Adjustment (BBA). The software presented a set of georeferenced points, also known as point cloud or point cloud, then the software generated a digital elevation model (MDE). Data analysis was based on the generated DEM. This model stores the altimetric information of each pixel in a gray scale creating a raster file in the extension .TIF, which was worked in the software Quantum Gis (QGIS) where it was processed in order to obtain the volumetric quantification. With this study it was possible to obtain relevant information from the study area, such as volume and height of the massif, slope angles, specific weight, evolution of the landfill geometry and cover material deposits over time and settlement of the massif.