An Analysis of the Influence of Flight Parameters in the Generation of Unmanned Aerial Vehicle (UAV) Orthomosaicks to Survey Archaeological Areas

摘要

This article describes the configuration and technical specifications of a multi-rotorunmanned aerial vehicle (UAV) using a red–green–blue (RGB) sensor for the acquisition of imagesneeded for the production of orthomosaics to be used in archaeological applications. Several flightmissions were programmed as follows: flight altitudes at 30, 40, 50, 60, 70 and 80 m above groundlevel; two forward and side overlap settings (80%–50% and 70%–40%); and the use, or lack thereof,of ground control points. These settings were chosen to analyze their influence on the spatialquality of orthomosaicked images processed by Inpho UASMaster (Trimble, CA, USA). Changes inillumination over the study area, its impact on flight duration, and how it relates to these settingsis also considered. The combined effect of these parameters on spatial quality is presented as well,defining a ratio between ground sample distance of UAV images and expected root mean square of aUAV orthomosaick. The results indicate that a balance between all the proposed parameters is usefulfor optimizing mission planning and image processing, altitude above ground level (AGL) beingmain parameter because of its influence on root mean square error (RMSE).