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Kites in Agrarian Regions
Published in K. R. Krishna, Aerial Robotics in Agriculture, 2021
Primarily, kites are cost effective aerial platforms. Kites are easy for those who wish to study ecological aspects of a location. Kites are good platforms for light weight photographic equipment. Now, let us quote an example wherein KAP has been used consistently, to study the changes in the habitat. The Chesapeake area in Massachusetts (USA) is home to salt marshes. The salt marshes support a diverse flora and fauna that are spatially and temporally dynamic. Aerial photography using an unmanned aerial vehicle is possible. As stated above, kite-aided aerial photography has been used effectively to study marshes around Chesapeake Bay (CBEC, 2019; Plate 5.10). Reports suggest that kites with sensors are also useful to monitor atmospheric conditions. The kite aerial photography has helped in monitoring the behavior of invasive plant species in marshes. Kites could be lofted repeatedly and quickly to study the invasive grass species such as Phragmites. They have found that Phragmites grass covers, crowds and deters other species from proliferating in the marshes. At the same time, kites carrying atmospheric probes could record data above each spot from where ecological data has been accrued using kite-aided photography (CBEC, 2019; see Plate 5.10). We may note that, National Aeronautics and Space Agency (NASA) too utilizes tethered kites to assess terrain and atmospheric conditions (NASA 2019; Padgett, 2019; Plate 5.10). The sensors are grouped in an ‘Aeropod’ (sensors in a gimble) attached to kite’s tether.
Development of Autonomous Vehicles
Published in Diego Galar, Uday Kumar, Dammika Seneviratne, Robots, Drones, UAVs and UGVs for Operation and Maintenance, 2020
Diego Galar, Uday Kumar, Dammika Seneviratne
An unmanned aerial vehicle (UAV) is an aircraft without a human pilot on board. The vehicle is controlled either autonomously by attached microprocessors or telemetrically by an operator on the ground. UAVs can be used to execute observation or detection missions through automatic or remote control. They are mainly used in mapping applications, environmental change monitoring, disaster prevention response, resource exploration etc. Compared to other flying vehicles and satellite remote sensing technology, UAVs have two advantages when capturing aerial photographs: low cost and high mobility. However, they have many environmental restrictions on their use due to low flight stability. Therefore, how to use UAVs in different scenarios so that spatial information for qualitative and quantitative analysis can be reliably processed and produced is an important issue impacting their application (Liu et al., 2014).
Application of Image Processing and Data in Remote Sensing
Published in Ankur Dumka, Alaknanda Ashok, Parag Verma, Poonam Verma, Advanced Digital Image Processing and Its Applications in Big Data, 2020
Ankur Dumka, Alaknanda Ashok, Parag Verma, Poonam Verma
Aeroplane System/Aerial Photography: This is one of the oldest and widely used methods for remote sensing. In this photography, cameras are mounted on light aircraft flying from a range of 200–1500 meters used for capturing a quantity of detailed information. Aerial photos provide an instant visual inventory of a portion of the Earth’s surface and can be used to create detailed maps. Aerial photographs commonly are taken by commercial aerial photography firms which have and operate specially modified aircraft equipped with large format (23 cm × 23 cm) mapping quality cameras. Aerial photos can also be taken using small format cameras (35 mm and 70 mm), hand-held or mounted, in unmodified light aircraft.
Creating Historical Building Models by Deep Fusion of Multi-Source Heterogeneous Data Using Residual 3D Convolutional Neural Network
Published in International Journal of Architectural Heritage, 2023
In aerial photography, the UAV flies at an altitude higher than the building roof and its camera lens angle is fixed, there are many blind spots because of the limitations of the ground trees and the view angles. The blind spots in photography make some textures in a building model miss, which seriously affects the modeling results. For example, in the UAV ortho-images, the ground resolution in the UAV aerial photograph is inversely proportional to the UAV altitude. When the airborne camera focal length and the photograph pixels are fixed, along with the increase of the height between the ground object and the UAV, the aerial photograph resolution decreases continuously. Therefore, the resolution on a building top is higher but on its bottom is lower in a UAV aerial photograph, which results in a conclusion that the model texture on the building top is good but on its bottom is poor. Other surveying or photography tools are needed to tackle this problem.
Remote sensing of mangroves using unmanned aerial vehicles: current state and future directions
Published in Journal of Spatial Science, 2021
Edward Zimudzi, Ian Sanders, Nicholas Rollings, Christian W. Omlin
Aerial photography was the only source of mangrove image data prior to the introduction of satellite imagery. It was, therefore used to track temporal changes among mangroves (Heumann 2011, Kuenzer et al. 2011). It had limitations of areal extent with very high costs of data acquisition over large geographic areas. Recent advances in UAVs, also called drones has made aerial photography and videography among the dominant remote sensing approaches in mapping small areas (Candiago et al. 2015; Heenkenda etal.2015). A variety of sensors can be mounted on these UAVs, including multispectral, RGB, and hyperspectral and RADAR and LIDAR. These UAVs, unlike satellite sensors, cover a specific geographic area of interest. They are able to fly at required altitudes and to produce varying levels of resolution, typically centimetre spatial resolution if required.
Distributed synchronous cooperative tracking algorithm for ground moving target in urban by UAVs
Published in International Journal of Systems Science, 2021
Chaofang Hu, Ge Qu, Hyo-Sang Shin, Antonios Tsourdos
Unmanned aerial vehicles (UAVs) have been widely used in various fields, such as logistics, aerial photography and military operations. Especially, when a terrorist attack or a crime occurs in cities, the UAV can be used for aerial searching and tracking. To track the ground moving target, Shaferman and Shima (2008) develop a genetic algorithm to compute optimal path in real time. In Meng et al. (2017), the decentralised control of multi-UAV is considered for autonomous takeoff, searching, tracking and the optimal UAV path is determined based on a geometric approach. However, in the case of a complex environment, it is hard to use a single UAV to implement tracking task. Therefore, multi-UAV's cooperative work is prospective in actual applications. In the mid-1970s, the multi-UAV cooperation was proposed and attracted great attention (Berni et al., 2009; Lin et al., 2019; Saito et al., 2019; J. Yao & Xu, 2019, november). Farmani et al. (2017) present a decentralised multi-target tracking system based on distributive clustering algorithm.