AVALIAÇÃO DA ACURÁCIA ALTIMÉTRICA USANDO A TECNOLOGIA VANT

Abstract

Using Unmanned Aerial Vehicles (UAV) for data acquisition is an effectual alternative for obtaining spatial data. Technological advances focused in development of UAVs, applied in the extraction of geospatial information, prove to be a tool for the production of Digital Elevation Models (DEM). The quality of the metric information of DEMs is related to the type of survey and processing methodologies. Thus, cartographic quality control methods should be used to determine the accuracy of the metrics. In this work, the methods of CAS-DCP (Cartographic Accuracy Standard for Digital Cartographic Products) and NSSDA (National Standard for Spatial Data Accuracy) were used to evaluate the vertical accuracy of the DEM produced by UAV. Aerophotogrammetric procedures yielded a 3.24 cm/px in Ground Sample Distance (GSD) Digital Elevation Model, corresponding to CAS-DCP Class A for a usual scale of 1: 1,000 (1m vertical equidistance according to Technical Specification for Vector Geospatial Data Acquisition). Regarding the NSSDA, the accuracy values obtained in the slope classes were: 0.156; 0.131 and 0.125 m. Therefore, the DEM generated by UAV photogrammetry techniques has a cadastral nature, given the classification of use concerning the scale used.