Micro air vehicles energy transportation for a wireless power transfer system

The aim of this work is to demonstrate the feasibility use of an Micro air vehicles (MAV) in order to power wirelessly an electric system, for example, a sensor network, using low-cost and open-source elements. To achieve this objective, an inductive system has been modelled and validated to power wirelessly a sensor node using a Crazyflie 2.0 as MAV. The design of the inductive system must be small and light enough to fulfil the requirements of the Crazyflie. An inductive model based on two resonant coils is presented. Several coils are defined to be tested using the most suitable resonant configuration. Measurements are performed to validate the model and to select the most suitable coil. While attempting to minimize the weight at transmitter’s side, on the receiver side it is intended to efficiently acquire and manage the power obtained from the transmitter. In order to prove its feasibility, a temperature sensor node is used as demonstrator. The experiment results show successfully energy transportation by MAV, and wireless power transfer for the resonant configuration, being able to completely charge the node battery and to power the temperature sensor.Peer ReviewedPostprint (published version

Autonomous wireless self-charging for multi-rotor unmanned aerial vehicles

Rotary-wing unmanned aerial vehicles (UAVs) have the ability to operate in confined spaces and to hover over point of interest, but they have limited flight time and endurance. Conventional contact-based charging system for UAVs has been used, but it requires high landing accuracy for proper docking. Instead of the conventional system, autonomous wireless battery charging system for UAVs in outdoor conditions is proposed in this paper. UAVs can be wirelessly charged using the proposed charging system, regardless of yaw angle between UAVs and wireless charging pad, which can further reduce their control complexity for autonomous landing. The increased overall mission time eventually relaxes the limitations on payload and flight time. In this paper, a cost effective automatic recharging solution for UAVs in outdoor environments is proposed using wireless power transfer (WPT). This research proposes a global positioning system (GPS) and vision-based closed-loop target detection and a tracking system for precise landing of quadcopters in outdoor environments. The system uses the onboard camera to detect the shape, color and position of the defined target in image frame. Based on the offset of the target from the center of the image frame, control commands are generated to track and maintain the center position. Commercially available AR.Drone. was used to demonstrate the proposed concept which is equppied with bottom camera and GPS. Experiments and analyses showed good performance, and about 75% average WPT efficiency was achieved in this research

Wireless Power Transfer for 3D Printed Unmanned Aerial Vehicle (UAV) Systems

Unmanned aerial vehicles (UAVs) have attracted a lot of attention for various applications such as service delivery, pollution mitigation, farming, and rescue operations over the past few years. However, the short duration of battery and the inconvenience of changing it is always a problem. Basically, small UAVs can only carry very limited payloads otherwise the battery will be drained more frequently. This project presents an automatic and high-efficient wireless power transfer (WPT) to supply a 3D printed UAV. A UAV has been 3D printed with wireless power transfer kit implemented to charge 3S 1500 mAh Li-Po battery with up to 1000 mAh automatically once it is landed, without manual operation. 24V DC is supplied to the transmitting side of WPT with the operating frequency at 180kHz and once the battery is fully charged, the charging process will also stop automatically

A Review on UAV Wireless Charging: Fundamentals, Applications, Charging Techniques and Standards

Unmanned Aerial Vehicles (UAVs) are becoming increasingly popular for applications such as inspections, delivery, agriculture, surveillance, and many more. It is estimated that, by 2040, UAVs/drones will become a mainstream delivery channel to satisfy the growing demand for parcel delivery. Though the UAVs are gaining interest in civil applications, the future of UAV charging is facing a set of vital concerns and open research challenges. Considering the case of parcel delivery, handling countless drones and their charging will become complex and laborious. The need for non-contact based multi-device charging techniques will be crucial in saving time and human resources. To efficiently address this issue, Wireless Power Transmission (WPT) for UAVs is a promising technology for multi-drone charging and autonomous handling of multiple devices. In the literature of the past five years, limited surveys were conducted for wireless UAV charging. Moreover, vital problems such as coil weight constraints, comparison between existing charging techniques, shielding methods and many other key issues are not addressed. This motivates the author in conducting this review for addressing the crucial aspects of wireless UAV charging. Furthermore, this review provides a comprehensive comparative study on wireless charging's technical aspects conducted by prominent research laboratories, universities, and industries. The paper also discusses UAVs' history, UAVs structure, categories of UAVs, mathematical formulation of coil and WPT standards for safer operation.publishedVersio

An Assessment of Shortest Prioritized Path-Based Bidirectional Wireless Charging Approach Toward Smart Agriculture

The agriculture sector has witnessed a transformation with the advent of smart sensing devices, leading to improved crop yield and quality. However, the management of data collection from numerous sensors across vast agricultural areas, as well as the associated charging requirements, presents significant challenges. This paper addresses the major research problem by proposing an innovative solution for charging agricultural sensors. The introduction of an energy-constrained device (ECD) enables wireless charging and transmission of soil data to a centralized server. The proposed ECDs will enable enhanced data collection, precision agriculture, optimized resource allocation, timely decision-making, and remote monitoring and control. A bidirectional wireless charging drone is employed to efficiently charge the ECDs. To optimize energy usage, a prioritized Dijkstra algorithm determines the ECDs to be charged and plans the shortest route for the drone. The wireless charging drone landing-charging station achieves an efficiency of 91.3%, delivering 72 W of power within a 5 mm range. Furthermore, the ECD possesses a data transmission range of 100 m and incorporates deep sleep functionality, allowing for a remarkable 30-day battery life.publishedVersio

Localization and detection of wireless embeddable structural sensors using an unmanned aerial vehicle in the absence of visual markers

The objective of this thesis is to develop a fully integrated UAV based platform for autonomous collection of data from embedded sensors. Passive (battery-less) embedded sensors provide means for periodic long-term monitoring of civil structures like bridges. However, collection of data from these sensors requires extensive manual effort of locating them. UAVs can automate this process, although localization of these embedded tags in absence of visual markers pose a challenge. A RF (13.56MHz) reader is used to capture data from RF tags wirelessly. Different tag coil sizes are tested to observe effects on read range as well as to characterize the interaction volume between reader and tag. The UAV platform is integrated with the RF reader to autonomously capture data from tags using GPS based localization. Different sensor configurations are tested and characterized to meet the requirements of X,Y,Z localization set by the reader and tag interaction volume. Flight characteristics are also observed for various UAV navigation parameters. Results suggest that by using low-cost RTK GPS unit, the UAV is capable of detecting and localizing RF tags without any visual markers or aides.Electrical and Computer Engineerin

Autonomous environmental protection drone

During the summer, forest fires are the main reason for deforestation and the damage caused to homes and property in different communities around the world. The use of Unmanned Aerial Vehicles (UAVs, and also known as drones) applications has increased in recent years, making them an excellent solution for difficult tasks such as wildlife conservation and forest fire prevention. A forest fire detection system can be an answer to these tasks. Using a visual camera and a Convolutional Neural Network (CNN) for image processing with an UAV can result in an efficient fire detection system. However, in order to be able to have a fully autonomous system, without human intervention, for 24-hour fire observation and detection in a given geographical area, it requires a platform and automatic recharging procedures. This dissertation combines the use of technologies such as CNNs, Real Time Kinematics (RTK) and Wireless Power Transfer (WPT) with an on-board computer and software, resulting in a fully automated system to make forest surveillance more efficient and, in doing so, reallocating human resources to other locations where they are most needed.Durante o verão, os incêndios florestais constituem a principal razão do desflorestamento e dos danos causados às casas e aos bens das diferentes comunidades de todo o mundo. A utilização de veículos aéreos não tripulados (VANTs), em inglês denominados por Unmanned Aerial Vehicles (UAVs) ou Drones, aumentou nos últimos anos, tornando-os uma excelente solução para tarefas difíceis como a conservação da vida selvagem e prevenção de incêndios florestais. Um sistema de deteção de incêndio florestal pode ser uma resposta para essas tarefas. Com a utilização de uma câmara visual e uma Rede Neuronal Convolucional (RNC) para processamento de imagem com um UAV pode resultar num eficiente sistema de deteção de incêndio. No entanto, para que seja possível ter um sistema completamente autónomo, sem intervenção humana, para observação e deteção de incêndios durante 24 horas, numa dada área geográfica, requer uma plataforma e procedimentos de recarga automática. Esta dissertação reúne o uso de tecnologias como RNCs, posicionamento cinemático em tempo real (RTK) e transferência de energia sem fios (WPT) com um computador e software de bordo, resultando num sistema totalmente automatizado para tornar a vigilância florestal mais eficiente e, ao fazê-lo, realocando recursos humanos para outros locais, onde estes são mais necessários

UAV Control in Close Proximities - Ceiling Effect on Battery Lifetime

With the recent developments in the unmanned aerial vehicles (UAV), it is expected them to interact and collaborate with their surrounding objects, other robots and people in order to wisely plan and execute particular tasks. Although these interaction operations are inherently challenging as compared to free-flight missions, they might bring diverse advantages. One of them is their basic aerodynamic interaction during the flight in close proximities which can result in a reduction of the controller effort. In this study, by collecting real-time data, we have observed that the current drawn by the battery can be decreased while flying very close to the surroundings with the help of the ceiling effect. For the first time, this phenomenon is analyzed in terms of battery lifetime degradation by using a simple full equivalent cycle counting method. Results show that cycling related effect on battery degradation can be reduced by a 15.77% if the UAV can utilize ceiling effect.Comment: ICoIAS 201

Design and development of multiband antennas for unmanned aerial vehicles (UAVs)

Abstract. This thesis aims to design and analyze microstrip patch antennas for unmanned aerial vehicles (UAVs) for Internet of Things (IoT) communication. With the growing need for reliable and efficient communication in UAV, understanding the unique challenges and requirements of antenna design for UAV-based communication systems becomes crucial. During the process of antenna integration onto the UAV body, important attention must be given to vital factors including the availability of mounting space, weight limitations, and radiation parameters. In this study, extensive efforts were made in the design of the antenna to meet the specific requirements for UAV applications. The antenna structure chosen was a microstrip patch antenna with an inset feed technique. The design aimed at optimizing the antenna for multi-band operation, ensuring compatibility with various communication frequencies. Careful considerations were made regarding size, weight, and functionality to ensure the antenna’s suitability for UAV applications. The first part of the thesis introduces the antenna theory, highlighting significant parameters such as radiation pattern, gain, and efficiency, which are crucial for UAV antenna design. The methodology for selecting various parameters is explained, and the radiation pattern and gain of two commercially available antennas were measured in the SATIMO chamber as a benchmark. The fabricated microstrip patch antenna was also tested both with and without the presence of a UAV to examine the impact of the UAV’s body on its performance. The designed antenna demonstrated a semi-omnidirectional pattern at sub-gigahertz frequencies, achieving a gain value exceeding 6 dBi, thereby fulfilling the requirements for UAV applications. The second part of this thesis focused on further advancements in the design process. Efforts were made to improve the antenna’s performance and behavior through various design modifications and optimizations. The design process involved iterative steps, such as adjusting the dimensions and parameters of the antenna to enhance its performance metrics. The results obtained demonstrated notable improvements in terms of radiation patterns with 92 degree of 3 dB angular beamwidth, gain enhancement up to 6.7 dBi, and overall antenna performance. These findings contribute to the body of knowledge in UAV antenna design and highlight the potential for further advancements in this field