1,188 results match your criteria aerial vehicle

Extraction of crown width based on the method of optimized watershed with multi-scale markers.

Ying Yong Sheng Tai Xue Bao 2021 Jul;32(7):2449-2457

Research Center of Forestry Remote Sensing & Information Engineering, Central South University of Forestry and Technology, Changsha 410004, China.

In view of the limitation of scale on the spatial structure of ground objects and the problem that traditional watershed segmentation tends to produce crown over-segmentation, we proposed a segmentation method of crown based on the optimized watershed with multi-scale markers, with the base in Mingyue Village of Changsha County as the research object. Firstly, the high-resolution unmanned aerial vehicle (UAV) was used to collect images. The image features were analyzed to construct the classification system of , and the distribution area of was extracted. Read More

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GPS-Free, Error Tolerant Path Planning for Swarms of Micro Aerial Vehicles with Quality Amplification .

Sensors (Basel) 2021 Jul 10;21(14). Epub 2021 Jul 10.

Institute of Computing, University of Campinas, 13083-852 Campinas, Brazil.

We present an error tolerant path planning algorithm for Micro Aerial Vehicle (MAV) swarms. We assume navigation without GPS-like techniques. The MAVs find their path using sensors and cameras, identifying and following a series of visual landmarks. Read More

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Machine Learning for the Dynamic Positioning of UAVs for Extended Connectivity.

Sensors (Basel) 2021 Jul 5;21(13). Epub 2021 Jul 5.

Department of Electronics, Telecommunications and Informatics (DETI), University of Aveiro, 3810-193 Aveiro, Portugal.

Unmanned Aerial Vehicle (UAV) networks are an emerging technology, useful not only for the military, but also for public and civil purposes. Their versatility provides advantages in situations where an existing network cannot support all requirements of its users, either because of an exceptionally big number of users, or because of the failure of one or more ground base stations. Networks of UAVs can reinforce these cellular networks where needed, redirecting the traffic to available ground stations. Read More

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General Purpose Low-Level Reinforcement Learning Control for Multi-Axis Rotor Aerial Vehicles.

Sensors (Basel) 2021 Jul 2;21(13). Epub 2021 Jul 2.

Department of Mechanical Engineering, National Yang Ming Chiao Tung University, Hsinchu City 30010, Taiwan.

This paper proposes a multipurpose reinforcement learning based low-level multirotor unmanned aerial vehicles control structure constructed using neural networks with model-free training. Other low-level reinforcement learning controllers developed in studies have only been applicable to a model-specific and physical-parameter-specific multirotor, and time-consuming training is required when switching to a different vehicle. We use a 6-degree-of-freedom dynamic model combining acceleration-based control from the policy neural network to overcome these problems. Read More

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Feature Matching Combining Radiometric and Geometric Characteristics of Images, Applied to Oblique- and Nadir-Looking Visible and TIR Sensors of UAV Imagery.

Sensors (Basel) 2021 Jul 4;21(13). Epub 2021 Jul 4.

School of Civil and Environmental Engineering, Yonsei University, Seoul 03722, Korea.

A large amount of information needs to be identified and produced during the process of promoting projects of interest. Thermal infrared (TIR) images are extensively used because they can provide information that cannot be extracted from visible images. In particular, TIR oblique images facilitate the acquisition of information of a building's facade that is challenging to obtain from a nadir image. Read More

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Virtual Electric Dipole Field Applied to Autonomous Formation Flight Control of Unmanned Aerial Vehicles.

Sensors (Basel) 2021 Jul 1;21(13). Epub 2021 Jul 1.

Automatic Control and Robotics Department, Faculty of Electrical Engineering, Bialystok University of Technology, Wiejska St. 45E, 15-351 Bialystok, Poland.

The following paper presents a method for the use of a virtual electric dipole potential field to control a leader-follower formation of autonomous Unmanned Aerial Vehicles (UAVs). The proposed control algorithm uses a virtual electric dipole potential field to determine the desired heading for a UAV follower. This method's greatest advantage is the ability to rapidly change the potential field function depending on the position of the independent leader. Read More

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Prediction of plant-level tomato biomass and yield using machine learning with unmanned aerial vehicle imagery.

Plant Methods 2021 Jul 15;17(1):77. Epub 2021 Jul 15.

Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo, 183-8509, Japan.

Background: The objective of this study is twofold. First, ascertain the important variables that predict tomato yields from plant height (PH) and vegetation index (VI) maps. The maps were derived from images taken by unmanned aerial vehicles (UAVs). Read More

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Towards locust-inspired gliding wing prototypes for micro aerial vehicle applications.

R Soc Open Sci 2021 Jun 30;8(6):202253. Epub 2021 Jun 30.

The Computational Intelligence Lab (CIL), School of Computer Science, University of Lincoln, LN6 7TS Lincoln, UK.

In aviation, gliding is the most economical mode of flight explicitly appreciated by natural fliers. They achieve it by high-performance wing structures evolved over millions of years in nature. Among other prehistoric beings, locust is a perfect example of such natural glider capable of endured transatlantic flights that could inspire a practical solution to achieve similar capabilities on micro aerial vehicles. Read More

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Phenotyping Flowering in Canola ( L.) and Estimating Seed Yield Using an Unmanned Aerial Vehicle-Based Imagery.

Front Plant Sci 2021 17;12:686332. Epub 2021 Jun 17.

Department of Plant Sciences, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, SK, Canada.

Phenotyping crop performance is critical for line selection and variety development in plant breeding. Canola ( L.) flowers, the bright yellow flowers, indeterminately increase over a protracted period. Read More

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Peanut Leaf Wilting Estimation From RGB Color Indices and Logistic Models.

Front Plant Sci 2021 18;12:658621. Epub 2021 Jun 18.

School of Plant and Environmental Sciences, Virginia Tech, Tidewater AREC, Suffolk, VA, United States.

Peanut ( L.) is an important crop for United States agriculture and worldwide. Low soil moisture is a major constraint for production in all peanut growing regions with negative effects on yield quantity and quality. Read More

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Towards a Blockchain-Based Multi-UAV Surveillance System.

Front Robot AI 2021 15;8:557692. Epub 2021 Jun 15.

ISAE-SUPAERO, Université de Toulouse, Toulouse, France.

This study describes a blockchain-based multi-unmanned aerial vehicle (multi-UAV) surveillance framework that enables UAV coordination and financial exchange between system users. The objective of the system is to allow a set of Points-Of-Interest (POI) to be surveyed by a set of autonomous UAVs that cooperate to minimize the time between successive visits while exhibiting unpredictable behavior to prevent external agents from learning their movements. The system can be seen as a marketplace where the UAVs are the service providers and the POIs are the service seekers. Read More

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Identifying the Branch of Kiwifruit Based on Unmanned Aerial Vehicle (UAV) Images Using Deep Learning Method.

Sensors (Basel) 2021 Jun 29;21(13). Epub 2021 Jun 29.

College of Mechanical and Electronic Engineering, Northwest Agriculture & Forestry University, Xi'an 712100, China.

It is important to obtain accurate information about kiwifruit vines to monitoring their physiological states and undertake precise orchard operations. However, because vines are small and cling to trellises, and have branches laying on the ground, numerous challenges exist in the acquisition of accurate data for kiwifruit vines. In this paper, a kiwifruit canopy distribution prediction model is proposed on the basis of low-altitude unmanned aerial vehicle (UAV) images and deep learning techniques. Read More

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Soft-Tentacle Gripper for Pipe Crawling to Inspect Industrial Facilities Using UAVs.

Sensors (Basel) 2021 Jun 16;21(12). Epub 2021 Jun 16.

GRVC Robotics Laboratory, University of Seville, Avenida de los Descubrimientos, S/N, 41092 Seville, Spain.

This paper presents a crawling mechanism using a soft-tentacle gripper integrated into an unmanned aerial vehicle for pipe inspection in industrial environments. The objective was to allow the aerial robot to perch and crawl along the pipe, minimizing the energy consumption, and allowing to perform contact inspection. This paper introduces the design of the soft limbs of the gripper and also the internal mechanism that allows movement along pipes. Read More

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Improved Q-Learning Algorithm Based on Approximate State Matching in Agricultural Plant Protection Environment.

Entropy (Basel) 2021 Jun 11;23(6). Epub 2021 Jun 11.

College of Computer Science and Technology, Jilin University, Changchun 130012, China.

An Unmanned Aerial Vehicle (UAV) can greatly reduce manpower in the agricultural plant protection such as watering, sowing, and pesticide spraying. It is essential to develop a Decision-making Support System (DSS) for UAVs to help them choose the correct action in states according to the policy. In an unknown environment, the method of formulating rules for UAVs to help them choose actions is not applicable, and it is a feasible solution to obtain the optimal policy through reinforcement learning. Read More

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Multitemporal Mapping of Post-Fire Land Cover Using Multiplatform PRISMA Hyperspectral and Sentinel-UAV Multispectral Data: Insights from Case Studies in Portugal and Italy.

Sensors (Basel) 2021 Jun 9;21(12). Epub 2021 Jun 9.

Department of Earth Sciences, University of Firenze, Via La Pira 4, 50121 Firenze, Italy.

Wildfires have affected global forests and the Mediterranean area with increasing recurrency and intensity in the last years, with climate change resulting in reduced precipitations and higher temperatures. To assess the impact of wildfires on the environment, burned area mapping has become progressively more relevant. Initially carried out via field sketches, the advent of satellite remote sensing opened new possibilities, reducing the cost uncertainty and safety of the previous techniques. Read More

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Indoor Mapping of Magnetic Fields Using UAV Equipped with Fluxgate Magnetometer.

Sensors (Basel) 2021 Jun 18;21(12). Epub 2021 Jun 18.

Faculty of Aeronautics, Technical University of Košice, Rampová 7, 041 21 Košice, Slovakia.

Unmanned aerial vehicles (UAVs) are used nowadays in a wide range of applications, including monitoring, mapping, or surveying tasks, involving magnetic field mapping, mainly for geological and geophysical purposes. However, thanks to the integration of ultrasound-aided navigation used for indoor UAV flight planning and development in sensorics, the acquired magnetic field images can be further used, for example, to enhance indoor UAV navigation based on the physical quantities of the image or for the identification of risk areas in manufacturing or industrial halls, where workers can be exposed to high values of electromagnetic fields. The knowledge of the spatial distribution of magnetic fields can also provide valuable information from the perspective of the technical cleanliness. Read More

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Prototype Design and Experimental Evaluation of Autonomous Collaborative Communication System for Emerging Maritime Use Cases.

Sensors (Basel) 2021 Jun 3;21(11). Epub 2021 Jun 3.

Department of Telecommunications, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technicka 12, 616 00 Brno, Czech Republic.

Automated systems have been seamlessly integrated into several industries as part of their industrial automation processes. Employing automated systems, such as autonomous vehicles, allows industries to increase productivity, benefit from a wide range of technologies and capabilities, and improve workplace safety. So far, most of the existing systems consider utilizing one type of autonomous vehicle. Read More

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UAV-Based and WebRTC-Based Open Universal Framework to Monitor Urban and Industrial Areas.

Sensors (Basel) 2021 Jun 12;21(12). Epub 2021 Jun 12.

Department of Applied Computer Science, Faculty of Electrical Engineering, Automatic Control and Computer Science, Kielce University of Technology, Al. 1000-lecia P.P. 7, 25-314 Kielce, Poland.

Nowadays, we are observing a rapid development of UAV-based monitoring systems, which are faced with more and more new tasks, such as high temporal resolution and high spatial resolution of measurements, or Artificial Intelligence on board. This paper presents the open universal framework intended for fast prototyping or building a short series of specialized flying monitoring systems able to work in urban and industrial areas. The proposed framework combines mobility of UAV with IoT measurements and full-stack WebRTC communications. Read More

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Soil Nutrient Estimation and Mapping in Farmland Based on UAV Imaging Spectrometry.

Sensors (Basel) 2021 Jun 6;21(11). Epub 2021 Jun 6.

College of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China.

Soil nutrient is one of the most important properties for improving farmland quality and product. Imaging spectrometry has the potential for rapid acquisition and real-time monitoring of soil characteristics. This study aims to explore the preprocessing and modeling methods of hyperspectral images obtained from an unmanned aerial vehicle (UAV) platform for estimating the soil organic matter (SOM) and soil total nitrogen (STN) in farmland. Read More

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High-Gain Millimeter-Wave Patch Array Antenna for Unmanned Aerial Vehicle Application.

Sensors (Basel) 2021 Jun 6;21(11). Epub 2021 Jun 6.

Electronics Engineering Department, Hanbat National University, Daejeon 34158, Korea.

A high-gain millimeter-wave patch array antenna is presented for unmanned aerial vehicles (UAVs). For the large-scale patch array antenna, microstrip lines and higher-mode surface wave radiations contribute enormously to the antenna loss, especially at the millimeter-wave band. Here, the element of a large patch array antenna is implemented with a substrate integrated waveguide (SIW) cavity-backed patch fed by the aperture-coupled feeding (ACF) structure. Read More

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A Reinforcement Learning Routing Protocol for UAV Aided Public Safety Networks.

Sensors (Basel) 2021 Jun 15;21(12). Epub 2021 Jun 15.

Department of Electrical Engineering, Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad 45650, Pakistan.

In Public Safety Networks (PSNs), the conservation of on-scene device energy is critical to ensure long term connectivity to first responders. Due to the limited transmit power, this connectivity can be ensured by enabling continuous cooperation among on-scene devices through multipath routing. In this paper, we present a Reinforcement Learning (RL) and Unmanned Aerial Vehicle- (UAV) aided multipath routing scheme for PSNs. Read More

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Development of a Light-Weight Unmanned Aerial Vehicle for Precision Agriculture.

Sensors (Basel) 2021 Jun 28;21(13). Epub 2021 Jun 28.

Department of Mechanical and Industrial Engineering, University of Johannesburg, Johannesburg P.O. Box 2028, South Africa.

This paper describes the development of a modular unmanned aerial vehicle for the detection and eradication of weeds on farmland. Precision agriculture entails solving the problem of poor agricultural yield due to competition for nutrients by weeds and provides a faster approach to eliminating the problematic weeds using emerging technologies. This research has addressed the aforementioned problem. Read More

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ReStAC-UAV-Borne Real-Time SGM Stereo Optimized for Embedded ARM and CUDA Devices.

Sensors (Basel) 2021 Jun 7;21(11). Epub 2021 Jun 7.

Fraunhofer Center for Machine Learning, Fraunhofer Institute of Optronics, System Technologies and Image Exploitation (IOSB), 76131 Karlsruhe, Germany.

With the emergence of low-cost robotic systems, such as unmanned aerial vehicle, the importance of embedded high-performance image processing has increased. For a long time, FPGAs were the only processing hardware that were capable of high-performance computing, while at the same time preserving a low power consumption, essential for embedded systems. However, the recently increasing availability of embedded GPU-based systems, such as the NVIDIA Jetson series, comprised of an ARM CPU and a NVIDIA Tegra GPU, allows for massively parallel embedded computing on graphics hardware. Read More

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A Test on the Potential of a Low Cost Unmanned Aerial Vehicle RTK/PPK Solution for Precision Positioning.

Sensors (Basel) 2021 Jun 4;21(11). Epub 2021 Jun 4.

Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Nazionale Terremoti, Sede Irpinia, 83035 Grottaminarda AV, Italy.

This paper investigated the achievable accuracy from a low-cost RTK (Real Time Kinematic)/PPK (Post Processing Kinematic) GNSS (Global Navigation Satellite Systems) system installed on board a UAV (Unmanned Aerial Vehicle), employing three different types of GNSS Bases (Alloy, RS2 and RING) working in PPK mode. To evaluate the quality of the results, a set of seven GCPs (Ground Control Points) measured by means of the NRTK (Network Real Time Kinematic) technique was used. The outcomes show a RMSE (Root Mean Square Error) of 0. Read More

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Energy Optimization in Dual-RIS UAV-Aided MEC-Enabled Internet of Vehicles.

Sensors (Basel) 2021 Jun 27;21(13). Epub 2021 Jun 27.

Department of Informatics, University of Western Macedonia, Fourka Area, 52100 Kastoria, Greece.

Mobile edge computing (MEC) represents an enabling technology for prospective Internet of Vehicles (IoV) networks. However, the complex vehicular propagation environment may hinder computation offloading. To this end, this paper proposes a novel computation offloading framework for IoV and presents an unmanned aerial vehicle (UAV)-aided network architecture. Read More

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Tracking Fluorescent Dye Dispersion from an Unmanned Aerial Vehicle.

Sensors (Basel) 2021 Jun 5;21(11). Epub 2021 Jun 5.

Faculty of Civil and Environmental Engineering, Gdansk University of Technology, 80-233 Gdańsk, Poland.

Commercial unmanned aerial vehicles continue to gain popularity and their use for collecting image data and recording new phenomena is becoming more frequent. This study presents an effective method for measuring the concentration of fluorescent dyes (fluorescein and Rhodamine WT) for the purpose of providing a mathematical dispersion model. Image data obtained using a typical visible-light camera was used to measure the concentration of the dye floating on water. Read More

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Influence of environmental and anthropogenic acoustic cues in sea-finding of hatchling leatherback (Dermochelys coriacea) sea turtles.

PLoS One 2021 1;16(7):e0253770. Epub 2021 Jul 1.

Department of Environmental Studies, Gettysburg College, Gettysburg, Pennsylvania, United States of America.

Although the visual and geomagnetic orientation cues used by sea turtle hatchlings during sea-finding have been well studied, the potential for auditory stimuli to act as an orientation cue has not been explored. We investigated the response of sea turtle hatchlings to natural and anthropogenic noises present on their nesting beaches during sea-finding. The responses of hatchling leatherback sea turtles, Dermochelys coriacea, collected from the Sandy Point National Wildlife Refuge, St. Read More

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Drones That Deliver: Pheromone-Based Mating Disruption Deployed via Uncrewed Aerial Vehicles in U.S. Cranberries.

J Econ Entomol 2021 Jun 28. Epub 2021 Jun 28.

Department of Entomology, University of Wisconsin-Madison, Madison, WI, USA.

Cranberry fruitworm (Acrobasis vaccinii Riley (Lepidoptera: Pyralidae)) and blackheaded fireworm (Rhopobota naevana Hubner (Lepidoptera: Tortricidae)) threaten cranberry production annually by causing significant fruit damage. Up to four pesticide applications are made each year to control these insects, which are costly to producers and elevate pesticide residues in fruit. Pheromone-based mating disruption technology can provide control of these pests in cranberry production, with the potential to minimize, or eliminate, pesticide applications. Read More

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Comparing Deliveries of Sterile Codling Moth (Lepidoptera: Tortricidae) by Two Types of Unmanned Aerial Systems and from the Ground.

J Econ Entomol 2021 Jun 28. Epub 2021 Jun 28.

The New Zealand Institute for Plant and Food Research Limited, Private Bag 4704, Christchurch Mail Centre, Christchurch 8140, New Zealand.

New Zealand apple exports must meet strict phytosanitary measures to eliminate codling moth (Cydia pomonella Linnaeus) (Lepidoptera: Tortricidae) larval infestation. This study was part of a program attempting the localized eradication of codling moth within an isolated cluster of seven orchards (391 ha). A conventional management program of insecticide sprays and pheromone mating disruption was supplemented with weekly releases of sterile moths for 1-6 yr. Read More

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The use of an unoccupied aerial vehicle to survey shark species over sand and rocky-reef habitats in a marine protected area.

J Fish Biol 2021 Jun 27. Epub 2021 Jun 27.

Florida Atlantic University, Boca Raton, Florida, USA.

Cabo Pulmo National Park was established in 1995 and has since seen a large increase in fish biomass. An unoccupied aerial vehicle (UAV) was used to survey shallow coastal habitat in which lemon sharks (Negaprion brevirostris), bull sharks (Carcharhinus leucas) and Pacific nurse sharks (Ginglymostoma unami) were recorded. Sharks were more common in the afternoon, potentially using warmer shallow areas to behaviourally thermoregulate. Read More

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