Montes de Oca Rebolledo, Andres (Center for Research in Optics, A.C.), Flores, Gerardo (Center for Research in Optics, A.C.)

A UAS Equipped with a Thermal Imaging System with Temperature Calibration for Crop Water Stress Index Computation

Scheduled for presentation during the Regular Session "UAS Applications II" (ThB4), Thursday, June 17, 2021, 14:00−14:20, Naoussa

2021 International Conference on Unmanned Aircraft Systems (ICUAS), June 15-18, 2021, Athens, Greece

This information is tentative and subject to change. Compiled on April 16, 2024

Abstract

This paper presents the development of an Unmanned Aerial System (UAS) for thermal imaging through the equipment of a thermal camera Flir Boson 640. The proposed UAS can capture and process the thermal imagery to compute an important vegetation index, as is the Crop Water Stress Index (CWSI). Such index is applicable to determine water stress and evaluate the irrigation process among vegetation. For the latter purposes, we present the image processing workflow to obtain the temperature map required for the computation of the CWSI. The image processing tasks applied to the imagery are a) image correction, b) orthomosaic generation, c) temperature calibration and d) vegetation index computation. For every task, we provide a detailed description. We have also designed an interface system based on a Raspberry Pi. The interface systems allows to collect the required imagery through the thermal camera, according to the trigger signal commanded by the autopilot. To assess the performance of the proposed system and methodology, we conduct experiments over a small area of a park. The results show that the CWSI can be computed effectively with our proposed methodology. The computed CWSI highlights water-stressed spots within the vegetation area. The developed code and open-source software used in this work are available on our Github page.