Using Photogrammetry through Unmanned Aerial Vehicles (UAV) as a Risk Assessment Tool: The Archaeological Chinampas of Xochimilco

Abstract

The development of the technology of unmanned aerial vehicles (UAV, drone) in the last decade has been vertiginous. Its use in the study of cultural heritage is growing and in this study we expose a workflow using an automated system of remote sensing by aerial photography through the use of a device that integrates a hexacopter to which two cameras have been adapted, one of them to obtain visible light (VIS) images, the other modified to capture the near infrared spectrum of light. We have taken as a case study a chinampa site in Xochimilco (El Japón) to evaluate its usefulness in the record and recognition of traits buried at shallow depth. By means of the photogrammetric processing of the stereopairs, the digital elevation model was generated to record a high resolution topography similar to that obtained through a LIDAR device, as well as other images in false color composition for the creation of standardized differential vegetation index (NDVI) maps that allow us to enhance archaeological features based on differences in growth and health of the vegetation