@MastersThesis{Oliveira:2017:AvUsSe,
author = "Oliveira, Luana Thayza de",
title = "Avalia{\c{c}}{\~a}o do uso de sensor termal a bordo de VANT
atrav{\'e}s de an{\'a}lises radiom{\'e}tricas, espectrais,
espaciais e posicionais",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2017",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2017-05-15",
keywords = "termal, VANT, caracteriza{\c{c}}{\~a}o de sensores,
exatid{\~a}o posicional, thermal infrared, UAV, characterization
of sensors, positional accuracy.",
abstract = "Dados obtidos na regi{\~a}o do infravermelho termal (Thermal
Infrared - TIR) podem revelar informa{\c{c}}{\~o}es n{\~a}o
vis{\'{\i}}veis importantes sobre os alvos observados. Tais
dados t{\^e}m aplica{\c{c}}{\~o}es nas mais diversas {\'a}reas
de monitoramento, seja ambiental, urbano ou agr{\'{\i}}cola.
Contudo, sua larga utiliza{\c{c}}{\~a}o esbarra em alguns
desafios: h{\'a} poucos sensores orbitais operacionais
dispon{\'{\i}}veis que atuam no TIR. E, dentre os sistemas TIR
existentes, precisa ser ainda considerada a sua
limita{\c{c}}{\~a}o quanto {\`a} frequ{\^e}ncia de imageamento
e resolu{\c{c}}{\~a}o espacial. Assim, o uso de sistemas de
sensores infravermelhos termais a bordo de aeronaves e, mais
recentemente, em ve{\'{\i}}culos a{\'e}reos n{\~a}o tripulados
(VANTs) tem sido crescente. Em contrapartida, poucos estudos
t{\^e}m explorado as caracter{\'{\i}}sticas dos sensores
aplicados nestas miss{\~o}es e tampouco a acur{\'a}cia dos dados
obtidos. Neste contexto, o objetivo deste trabalho foi avaliar as
capacidades radiom{\'e}tricas, espectrais e espaciais de dois
sensores termais comerciais, um deles desenvolvido para a
integra{\c{c}}{\~a}o em plataformas n{\~a}o tripuladas, bem
como avaliar exatid{\~a}o posicional dos produtos resultantes do
seu uso em um VANT, ortomosaico termal e modelo de
superf{\'{\i}}cie (MDS), segundo o Padr{\~a}o de Exatid{\~a}o
Cartogr{\'a}fica dos Produtos Cartogr{\'a}ficos Digitais
(PEC-PCD). Para tanto, foram realizados procedimentos
laboratoriais de caracteriza{\c{c}}{\~a}o dos dois sensores. Em
campo, foi realizado levantamento de dados termais utilizando um
VANT multirrotor quadric{\'o}ptero em uma {\'a}rea de
aproximadamente 10 mil mē, al{\'e}m de medi{\c{c}}{\~o}es
experimentais de quatro superf{\'{\i}}cies com diferentes tipos
de cobertura pelos dois sensores previamente caracterizados. Dos
experimentos laboratoriais de caracteriza{\c{c}}{\~a}o
espectral, resultaram as curvas da fun{\c{c}}{\~a}o de reposta
espectral (FRE) dos sensores, em que em ambos os casos, foi
poss{\'{\i}}vel verificar diferen{\c{c}}as na faixa de
atua{\c{c}}{\~a}o em rela{\c{c}}{\~a}o ao declarado pelos
fabricantes. Na an{\'a}lise radiom{\'e}trica um dos sensores
demonstrou ter incertezas superiores {\`a}s declaradas pelos
fabricantes, e na caracteriza{\c{c}}{\~a}o espacial, os valores
de EIFOV de cada um dos sensores foram obtidos. A an{\'a}lise dos
dados obtidos em campo, al{\'e}m de validar as incertezas de
medi{\c{c}}{\~a}o determinadas em laborat{\'o}rio, permitiu
verificar que, mesmo em baixas altitudes, a atmosfera pode exercer
influ{\^e}ncia sobre os dados termais e levar a conclus{\~o}es
err{\^o}neas sobre os alvos, sobretudo em an{\'a}lises
quantitativas. Da avalia{\c{c}}{\~a}o quanto {\`a}
exatid{\~a}o posicional, concluiu-se que o ortomosaico gerado sem
pontos de controle apresenta exatid{\~a}o planim{\'e}trica a
partir da escala 1:5.000 e altim{\'e}trica a partir de 1:50.000,
e o ortomosaico processado com 4 pontos de controle apresentou
exatid{\~a}o planim{\'e}trica a partir de 1:1.000 e
altim{\'e}trica a partir de 1:25.000. Desde que consideradas as
incertezas envolvidas no processo de obten{\c{c}}{\~a}o das
imagens termais por VANT, esta demonstrou ser uma alternativa
eficaz para imageamento de {\'a}reas com caracter{\'{\i}}sticas
n{\~a}o aparentes na faixa do vis{\'{\i}}vel. ABSTRACT: Data
obtained in the Thermal Infrared (TIR) part of the electromagnetic
spectrum may present invisible, but important, information from
the targets of interest. Such data are important in the most
different applications of environmental, urban and agriculture
monitoring. Nevertheless there are some challenges to its wide
use: presently there are few operational orbital TIR sensors
available, and among those there are limitations regarding its
imaging frequency and spatial resolution. Therefore the use of TIR
systems aboard aircrafts, and more recently on drones is growing.
On the other hand, few studies evaluated the characteristics of
the TIR sensors used in such missions and neither the accuracy of
the data obtained. In this frame, the objective of this study was
the evaluation of the radiometric, spectral and spatial capacities
of two commercial thermal sensors. One of them was developed for
the integration on unmanned platforms, as well as to evaluate the
positional accuracy of the resulting products for its use on a
drone, a thermal ortho-mosaic and a Digital Surface Model (DSM),
in accordance with the Brazilian Cartographic Accuracy Standard of
Digital Cartographic Products (PEC-PCD). In order to perform these
tasks, laboratory procedures were executed to characterize both
sensor systems. Afterwards a field survey of thermal data was
done, using a multi-rotor quadri-copter drone, at an area of
approximately 10,000 m2, besides experimental measurements on four
test-sites with different types of soil cover, using both
previously characterized sensors. From the laboratory works on
spectral characterization, frequency curves of both sensors were
obtained. It was verified that there were differences in the
respective performance bands, regarding what was declared by the
manufacturers. The radiometric analysis from one of the sensors
showed higher uncertainties than those declared, as well as at the
spatial characterization of EIFOV values, from each sensor. The
analysis of data obtained during the field survey, besides
validating the uncertainties from the measurements in the
laboratory, also showed that, even at low altitudes, the
atmosphere influences thermal data and can lead to erroneous
conclusions about targets, especially at a quantitative analysis.
Regarding the positional accuracy, it was concluded that the
ortho-mosaic obtained without ground control points, presents a
planimetric accuracy at 1:5,000 scale, and an altimetry accuracy
at 1:50,000. The ortho-mosaic processed with four control points
presented a planimetric accuracy starting at 1:1,000 and an
altimetry accuracy starting at 1:25,000. Taking into account the
uncertainties involved in the process to obtain thermal images
with a drone, this is an efficient alternative to image areas with
non-apparent characteristics in the visible spectrum.",
committee = "Almeida, Cl{\'a}udia Maria de (presidente) and Kux, Hermman
Johann Heinrich (orientador) and Korting, Thales Sehn and Castro,
Ruy Morgado de",
englishtitle = "Evaluation of the use of a thermal sensor on a uav through
radiometric, spectral, spatial and positional analysis",
language = "pt",
pages = "157",
ibi = "8JMKD3MGP3W34P/3NS677H",
url = "http://urlib.net/ibi/8JMKD3MGP3W34P/3NS677H",
targetfile = "publicacao.pdf",
urlaccessdate = "27 abr. 2024"
}