A Conceptual Model for Eco-Friendly Low-Cost Counter-Drone Defence Using Biodegradable Sticky Microfibers

A study was conducted for NASA Dryden Flight Research Center to investigate the viability of developing an externally powered zero stage booster fan to boost the altitude performance of a high altitude turbojet from 80 kft. to over 90 kft., in order to realize a very high altitude subsonic remotely piloted aircraft (RPA) capable of atmospheric science missions. A modified non-airbreathing torpedo engine powers the booster fan. The powered fan is grafted onto an airbreathing turbojet (the General Electric YJ97 jet engine) and is used to supercharge the engine (boost inlet pressure and airflow) at altitudes above its original design limits. The inlet boost keeps the engine operating and delivering thrust, at subsonic speeds, to mission altitudes over 95,000 ft. If this modified engine were grafted back into the air vehicle it was originally designed for (the Viet Nam era AQM-91A Compass Arrow) the modifications would enable the vehicle to increase its maximum altitude from 80,000 ft to over 88,000 ft for periods up to 45 min. With some additional wing area, the aircraft, which is in the 5000 lbm TOGW class, could carry a 500 lbm payload to altitudes over 92,000 kft with an operational radius over 1500 NMi. This study examined a number of candidate component arrangements to realize this fan-boosted propulsion system. Performance was estimated for the subsystem components, the resulting propulsion systems, and the associated RPA. In addition, the study estimated the time and cost to demonstrate/validate this concept in a full-scale propulsion system wind tunnel test program. This paper describes the concept, summarizes the concept selection efforts and performance analysis conducted during the study, and explains the rationale behind this unusual approach. A description of the proposed development and test program, and the cost estimate, lies beyond the scope of this paper.

The need for pedestrian target detection in uncrewed aerial vehicle (UAV) remote sensing images has become increasingly significant as the technology continues to evolve. UAVs equipped with high-resolution cameras can capture detailed imagery of various scenarios, making them ideal for monitoring and surveillance applications. Pedestrian detection is particularly crucial in scenarios such as traffic monitoring, security surveillance, and disaster response, where the safety and well-being of individuals are paramount. However, pedestrian detection in UAV remote sensing images poses several challenges. Firstly, the small size of pedestrians relative to the overall image, especially at higher altitudes, makes them difficult to detect. Secondly, the varying backgrounds and lighting conditions in remote sensing images can further complicate the task of detection. Traditional object detection methods often struggle to handle these complexities, resulting in decreased detection accuracy and increased false positives. Addressing the aforementioned concerns, this paper proposes a lightweight object detection model that integrates GhostNet and YOLOv5s. Building upon this foundation, we further introduce the SPD-Conv module to the model. With this addition, the aim is to preserve fine-grained features of the images during downsampling, thereby enhancing the model’s capability to recognize small-scale objects. Furthermore, the coordinate attention module is introduced to further improve the model’s recognition accuracy. In the proposed model, the number of parameters is successfully reduced to 4.77 M, compared with 7.01 M in YOLOv5s, representing a 32% reduction. The mean average precision (mAP) increased from 0.894 to 0.913, reflecting a 1.9% improvement. We have named the proposed model “GSC-YOLO”. This study holds significant importance in advancing the lightweighting of UAV target detection models and addressing the challenges associated with complex scene object detection.

One of the major limiting factors for the transmission of high power microwave (HPM) radiation is the interface between dielectric-vacuum, or even more severely, between dielectric-air if HPM is to be radiated into the atmosphere. Surface flashover phenomena which occur at these transitions severely limit the power levels which can be transmitted. It is of major technical importance to predict surface flashover events for a given window geometry, material and power level. When considering an aircraft based high power microwave platform, the effects on flashover formation due to variances in the operational environment corresponding to altitudes from sea level to 50,000 feet (760 Torr to 90 Torr) are of primary interest. The test setup is carefully designed to study the influence of each atmospheric variable without the influence of high field enhancement or electron injecting metallic electrodes.

Modern air defence systems are facing accelerated development of ballis tic, hypersonic, and unmanned threats that increasingly surpass the capa bilities of traditional defensive technologies. This paper analyses the main challenges posed to air defence by ballistic missiles and various categories of unmanned aerial vehicles. Through case studies from Ukraine, Israel, and the Gulf War, it illustrates the limited effectiveness of existing defence systems, particularly against sophisticated threats. Special attention is giv en to the concepts of air defence saturation through drone swarms and the economic implications of such tactics. In the final section, technological solutions for future defence are presented, including a multi-layered or bital sensor architecture, directed energy weapons, and electronic warfare systems. The paper concludes that the future effectiveness of air defence will depend on the ability to integrate various technologies into flexible and economically sustainable defence systems.

<div class="section abstract"><div class="htmlview paragraph">The availability of new technologies and the growing interest in the development of autonomous aircraft has created a demand for performance evaluation of aircraft flying at high altitudes over a long period of time for applications such as monitoring, telecommunications, etc. This work presents a study on the use of wings with high aspect ratio for the application in unmanned aircraft, that fly at high altitudes and require great endurance to remain flying as long as possible. With reference to the AeroVironment Helios aircraft, which hit the altitude record in 2001, flying at more than 29,000 meters altitude, a comparison was made between five wings with different wingspan from the aerodynamic and structural point of view. The aerodynamic performance of each wing was calculated and structural design and sizing was performed, assuming that it is the main structural component of the wing. Optimazing each wing aerodynamically and structurally, it was possible to compare wing performance in terms of maximum range and maximum endurance. The analysis focused on evaluate the aerodynamic and structural performance for a more efficient design that meets flight requirements. The results showed that the increase in wingspan improves the aerodynamic performance of the wing, but with the cost of increasing its structural weight. The wing with the largest wingspan (20% increase relative to the baseline wing), although presented the best aerodynamic characteristics, presented bad performance due to its heavy weight. However, the proposed modification of the original wing with 10% increase in wingspan presented the best performance in terms of range and endurance.</div></div>

The Internet of Things (IoT) is revolutionizing transportation, with the market surging from $135 billion USD in 2016. This growth highlights the integration of IoT devices, robotics, and automation, enhancing efficiency across various sectors. Robotics-based IoT merges robotics with IoT, enabling real-time communication and autonomous decision-making through sensor networks. In manufacturing, IoT-enabled robots optimize production by monitoring equipment health, predicting maintenance, and streamlining workflows, reducing downtime, and increasing productivity. In healthcare, robotic systems enhance patient care by monitoring vitals, administering medications, and performing precise surgeries, all while communicating with healthcare providers for coordinated care. The logistics sector benefits from autonomous drones and vehicles that optimize routes and manage inventory efficiently, ensuring timely deliveries and reducing human error. Keeping all these in contentions, Swarm robotics based unmanned transportation system using collaborative robots (ColBots), was conceived in this paper. Swarm robots are inspired by ant colonies, involving multiple wirelessly connected robots, communicating seamlessly, in an coordinated actions. This technology enables efficient teamwork for tasks like cleaning, assembly, and exploration of hazardous environments. Following this view, the following research work explores unmanned transport systems using swarm bots, highlighting the interaction between humans and robotics. The solution explores the concept of master and slave configuration pattern in order to boost the overlapping communication protocol. Using LiDAR as the main data actuation tool for automated navigation, a prototypic exploration on the same has been made to solve of generic tasks via the ColBots. The results suggests that this protype is capable enough to be used for most of general transportation services and can help in transportation on any scale whether be it inside a building or inside a city or across states.

<p>Introduced fish are a major threat for high altitude aquatic habitats and <em>Salvelinus fontinalis</em> have been widely used throughout the Alps for stocking lakes and rivers. Understanding its feeding ecology is a basic, but essential tool for interpreting its impact. To assess which factors determine the diet of <em>S. fontinalis</em> we analyzed more than 500 stomachs from several introduced populations from the Gran Paradiso National Park (GPNP, Western Italian Alps) and we measured the availability of several prey groups (zooplankton, aquatic invertebrates, terrestrial invertebrates). We complemented the study with a short, but exhaustive literature review on the <em>S. fontinalis</em> feeding ecology. In general the food composition reflected the availability of prey -confirming that <em>S. fontinalis</em> is an opportunistic predator- and was influenced by habitat type (stream <em>vs</em> lake), fish size, and seasonality. The obtained results were discussed in the light of the existing literature on the feeding ecology and ecological impact of <em>S. fontinalis</em>. Large benthonic insects account for a substantial part of the diet of stream dwelling brook trout, while they are almost absent both in the diet and in the prey species pool of lake-dwelling brook trout, probably reflecting a stronger ecological impact in the lakes.<strong> </strong></p>

A wide range and variety of reconnaissance and observation tasks, which were solved using strategic unmanned reconnaissance aircraft in military conflicts of the twentieth century, due to the need to update the features, conditions and problematic issues of its application.The purpose of the article. Systematize the features, conditions and problematic issues of the use of strategic unmanned reconnaissance aircraft in military conflicts of the 21st century.An analysis of the results of the hostilities inIraqin 1991 showed the need for the use of reconnaissance UAVs of extended stays in the air with a range of about 1,000 km and more.The creation and use of strategic-level unmanned vehicles was not relevant for all participants in military conflicts. So, if for the Israeli army, whose intelligence facilities were located mainly in the operational-tactical depth of up to400 km, this problem was irrelevant. For the US defense department, the potential reconnaissance facilities of which were located in overseas theaters of war, the question of the availability of strategic UAVs with the ability to control them from the mainland became after 1991 one of the top priorities.Afghanistanhas become the first region of use for the Global Hawk American UAV. Unlike the UAV Predator, the Global Hawk was a purely high-altitude strategic reconnaissance aircraft operating at high altitude to nearly20 km.The main difficulties of using Global Hawk, as it was later established, were to organize the management of these devices. So, to ensure the typical forAfghanistancombat operations of the Global Hawk UAV, it was necessary to have three satellite communication lines.Strategic reconnaissance UAVs has proved that in the difficult conditions of modern military conflicts, they perform more efficiently than manned aircraft to accomplish reconnaissance tasks to perform a number of tasks.Further research should be carried out in such topical areas: increasing the survivability of UAVs, developing approaches to using strategic UAVs in various combat conditions, improving the training system for crews of strategic UAVs, reducing the visibility of UAVs for anti-aircraft destruction of the enemy, and the like.

T HE development of aircraft guidance, navigation, and control systems has been a long-standing research area. Numerous methods relating to the enhancement of aircraft performance under various mission parameters have been developed in response to a need for more reliable and robust guidance systems. Current guidance systems applied to commercial, civilian, and unmanned aircraft rely on the knowledge of a flight path, specified bywaypoints located in inertial space. Most missions are considered successful when the vehicle reaches the designatedwaypoint at which new commands are issued to the vehicle to proceed to the next waypoint. Two common types of conventional aircraft guidance are the direct-to-waypoint (DTW) and track-to-waypoint (TTW) methods in relation to pathfollowing between designated waypoints. The DTWmethod simply issues heading commands to the vehicle based on the angular difference between thewaypoint and vehicle.When thevehicle reaches the waypoint, the control system issues a new command to guide the aircraft to the next waypoint. The TTW method aims to follow the track betweenwaypoints. In this guidancemethod the control system aims to minimize the lateral offset between the prescribed flight path and the aircraft’s position, issuing heading commands that return the vehicle to the nominal flight path. The track method therefore places the additional constraint on a flight path that the vehicle must follow in order to reach the waypoint, rather than simply reaching the waypoint. However, both methods are far from optimal. This is evident in how the aircraft transitions between flight paths after reaching awaypoint. During theseflight-path transitions, the aircraft will often overshoot the desiredflight path to correct its track, particularlywhen the flight-path transition angle is acute. Various control strategies have been investigated to alleviate or minimize flight-path deviations. Such strategies include applyingmodern control methods such as receding-horizon control [1,2] and model predictive control [3] to anticipate flight-path changes and take control action before reaching a goal while maintaining adequate vehicle flight performance. Missile guidance and control systems operate on similar principles to commercial, civilian, and unmanned aircraft guidance and control algorithms. The primary mission for missile systems is to intercept a moving target using information about the relative position and velocity between the pursuer and target. One of thefirstmethods used in missile guidance was pursuit guidance (PG) [4–7]. The method operates by forcing the angular displacement error between a pursuer and its target to zero. Control commands scaled by a proportional factor of the current error are then issued to direct the pursuer along the line of sight (LOS) between the pursuer and target. PG solutions, however, do not consider the path taken or the levels of system performance required by the pursuer in reaching the target, resulting in a far-from-optimal solution. To address this problem of suboptimality, additional parameters have been introduced to enhance missile performance. One method includes taking into account the motion of the commanded line of sight between the pursuer and target [4,7–10], issuing lateral acceleration commands based on tracking error and tracking error rate to the target. This approach has been shown to improve overall interceptor performance compared with conventional PG [4,7]. Another suchmethod aims tomodify the level of control the guidance algorithm possesses over the vehicle by adjusting the level of proportional gain. This is achieved by gain scheduling [11] to select gain values based on current interceptor states. In addition to modifying internal missile guidance and control parameters such as variable gains and LOS rate estimation, mission performance can be enhanced by manipulating the trajectory taken by the pursuer to the targets. A good example of such a method is discussed in [12], in which a missile aims to exploit the aerodynamic benefits of high-altitude flight by tracking a virtual target at some initially high altitude that is not necessarily along the trajectory to the true target. This Note discusses the development of a guidance law fusing the virtual-target concepts with those of pursuit guidance for implementation into an aircraft guidance system. This Note develops a path-following aircraft guidance algorithm that pursues synthetic waypoints using only a small set of guidance parameters, extending the virtual-target concept to complete aircraft guidance. The path is defined by the track between a minimal set of waypoints at specified locations, removing the need for a smooth path to be defined or the need for complicated path-switching logic or trajectory planning when awaypoint is reached. The synthetic waypoint travels along the path between waypoints, with the trailing aircraft traveling a smooth path generated through its own dynamics in following the synthetic waypoint. The guidance law is tested by varying guidance parameters, thus assessing vehicle sensitivity to and overall system performance of parameter variations. The following sections discuss the basic concepts of missile and aircraft guidance and provide a detailed description of the structure of the synthetic-waypoint guidance algorithm. A discussion on the implementation of the algorithm into the underlying aircraft control system will also be presented, followed by an analysis of the performance of the guidance algorithm in nonlinear simulation. Received 30 June 2009; revision received 3 November 2009; accepted for publication 9November 2009.Copyright©2009 by theAmerican Institute of Aeronautics and Astronautics, Inc. All rights reserved. Copies of this paper may be made for personal or internal use, on condition that the copier pay the $10.00 per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923; include the code 0731-5090/10 and $10.00 in correspondence with the CCC. ∗Graduate Research Student, School of Aerospace, Mechanical and Mechatronic Engineering; e.medagoda@aeromech.usyd.edu.au. Senior Lecturer, School of Aerospace, Mechanical and Mechatronic Engineering; pwg@aeromech.usyd.edu.au. JOURNAL OF GUIDANCE, CONTROL, AND DYNAMICS Vol. 33, No. 2, March–April 2010

This paper explains how to design a wireless communication system via high altitude platform stations HAPS to cover the specific area (Using Diwaniyah city area as a model). High altitude platform station HAPS is unmanned airplane provides the wireless communication service to the wider area. It is designed to work at high altitude between (17-22 Km) and coverage area 400 Km. This study illustrated for calculating the co-channel interference between HAPS ground station with a terrestrial station and satellite station. Free space losses for a HAPS ground station has been applied to meet the geographic of Diwaniyah city. In addition, explaining the relationship between elevation angles with the radius of the coverage area. Interference mitigation techniques have been given, such as improving the antenna radiation pattern, then it proposed the elevation angle for the HAPS's ground stations to reduce an interference between HAPS network with Fixed Service (FS) and fixed satellite service (FSS). Finally, this study explains the relationship between elevation angles with the radius of the coverage area. For more reliability, the Scenario for covers the city of Diwaniya. Two ground stations have been proposed to connect with high-altitude platform station.

Eucalyptus spp. and Acacia mearnsii are common exotic tree species in eastern Africa that have shown (strong) invasive behavior in some regions. Acacia mearnsii is considered a highly invasive species that is replacing native species and Eucalyptus spp. are known to consume high amounts of groundwater with suspected effects on native flora. Mapping the occurrence of these species in the Taita Hills, Kenya (part of the Eastern Arc Mountains Biodiversity Hotspot) is important as there is lack of knowledge on their occurrence and ecological impact in the area. Mapping methods that require a lot of fieldwork are impractical in areas like the Taita Hills, where the terrain is rugged and the infrastructure is poor. Our aim was hence to map the occurrence of these tree species in a 100 km2 area using airborne imaging spectroscopy and laser scanning. We used a one class biased support vector machine (BSVM) classifier as it needs labeled training data only for the positive classes (A. mearnsii and Eucalyptus spp.), which potentially reduces the amount of required fieldwork. We also introduce a new approach for parameterizing and setting the threshold level simultaneously for the BSVM classifier. The second aim was to link the occurrence of these species to selected environmental variables. The results showed that the BSVM classifier is suitable for mapping Acacia mearnsii and Eucalyptus spp., holding the potential to improve the efficiency of field data collection. The introduced parametrization/threshold selection method performed better than other commonly used approaches. The crown level F1-score was 0.76 for Eucalyptus spp. and 0.78 for A. mearnsii. We show that Eucalyptus spp. and A. mearnsii trees cover 0.8% and 1.6% of the study area, respectively. Both species are particularly located on steeper slopes and higher altitudes. Both species have significant occurrences in areas close to the biggest remaining native forest patch (Ngangao) in the study area. Nonetheless, follow-up studies are needed to evaluate their impact on the native flora and fauna, as well as their impact on the water resources. The maps created in this study in combination with such follow-up studies could serve as base data to generate guidelines that authorities can use to take action in handling the problems these species are causing.

In order to improve the overall performance of the reinforcement learning algorithm and enable multi-agent to complete collaborative navigation in a highly dynamic and multi-constrained complex environment, this paper proposes multi-agent collaborative navigation based on the theory of deep reinforcement learning algorithm, adopting the deep deterministic strategy gradient (MADDPG) technology and introducing the experience priority extraction mechanism and the information calculation optimization method to carry out simulation verification on the multi-agent autonomous navigation problem. The paper proposes PD-MADDPG, an enhanced multi-agent navigation algorithm. Through methods such as prioritized experience replay and adaptive message dropout, the multi-agent collaborative navigation algorithm significantly enhances navigation efficiency, robustness, and scalability in dynamic environments with obstacle, advancing autonomous like drone swarms and logistics robots.

Team Inspiration is a robotics team from San Diego, CA, consisting of passionate middle and high school students. We participate in a variety of robotics competitions including FIRST [1], Robocar [2], and RoboSub [3], an international collegiate level competition. In 2020, our team placed #1 against 33 university and high school teams making history as the youngest team to earn this title. In 2021 our team was accepted to compete in RobotX 2022 [4], an international collegiate competition utilizing an autonomous boat and drone working together. In 2011, our coaches created a team and imagined that one day, the elementary school students playing with Lego robots would grow to compete in RoboSub and beyond. Prior to 2019, our team only had experience with ground robots. We took advice and inspiration from experienced teams and connected with marine technology companies to seek mentorship. With the mentorship from professionals, we were encouraged to push ourselves. Through our speaker series, we learned from many professionals from a variety of STEM fields, especially from those in the marine industry. We learned alongside other students about the far-reaching applications of STEM. In 2019, we began our RoboSub journey starting with the basics: A simple remotely-operated vehicle (ROV) constructed by plastic pipes, brushless motors and on-off control box. We climbed up the complexity scale to prototyping on breadboards and using a reliable off-the-shelf Autonomous Underwater Vehicle (AUV) from Blue Robotics called BlueROV2 [5]. Learning from these platforms, we designed and built our custom AUV, Orange in 2019. The following year we developed Græy which took Orange’s design and improved upon it by adding more capabilities and sensors to incorporate intersub communication. In 2021, adapting to the virtual season we created an open source Unity simulation of the RoboSub competition environment to help our team and others to test their systems. We strive to apply our experience in RoboSub to benefit the local and global STEM education community. Thus, we began collaborating with Porpoise Robotics [6], a team of former submarine engineers, to design low cost underwater ROV to make STEM education more accessible. The ROV is designed to be an affordable robot which can be used to teach STEM, especially robotics and mechatronics, in schools. Sitting well within a consumer price range, the ROV gives schools the opportunity to immerse their students in underwater robotics. In addition to developing the ROV, we have been working with Porpoise Robotics to create a 2-week curriculum for schools to use with the ROV which will aim to teach students Python, underwater dynamics, mechanics, and electrical integration. By teaching young students about basic principles of marine technology and innovation, we hope to inspire them to explore their interest in the field of ocean engineering. The paper will detail how to inspire more engineers to spread their knowledge and help spark interest in marine education to explore the unknown wonderworld of the ocean.

Application of the gas turbine for use in unmanned military aircraft and missiles, industrial or vehicular power applications, and inexpensive general aviation aircraft is possible only through development of low-cost engine components. This paper presents the design and development of an annular fuel vaporizing combustor for a low-cost turbojet for use in a supersonic missile and other expendable or limited-life applications. The design of the low-cost gas turbine and the factors that influence the selection of component characteristics, design configurations, materials, and methods of manufacture are discussed. In order to provide high specific power, the highest burner temperature possible, without introducing design complexity and performance and cost penalties associated with turbine cooling, was selected. Consequently, the combustor's influence on turbine performance and durability had a significant effect on the engine design and cost. The combustor performance goals, including efficiency and temperature pattern factor as provided within envelope, reliability, and cost constraints, are described. An experimental combustor test program was conducted to evaluate the design pertaining to liner cooling, pyrotechnic ignition, fuel introduction, primary and dilution air distribution, and exit gas temperature profiles. The combustor test results and the influence of combustor performance on turbine life are discussed.

The purpose of the flow calibration analysis work is to provide Performance Assessment (PA) with the calibrated site-scale saturated zone (SZ) flow model that will be used to make radionuclide transport calculations. As such, it is one of the most important models developed in the Yucca Mountain project. This model will be a culmination of much of our knowledge of the SZ flow system. The objective of this study is to provide a defensible site-scale SZ flow and transport model that can be used for assessing total system performance. A defensible model would include geologic and hydrologic data that are used to form the hydrogeologic framework model; also, it would include hydrochemical information to infer transport pathways, in-situ permeability measurements, and water level and head measurements. In addition, the model should include information on major model sensitivities. Especially important are those that affect calibration, the direction of transport pathways, and travel times. Finally, if warranted, alternative calibrations representing different conceptual models should be included. To obtain a defensible model, all available data should be used (or at least considered) to obtain a calibrated model. The site-scale SZ model was calibrated using measured and model-generated water levels and hydraulic head data, specific discharge calculations, and flux comparisons along several of the boundaries. Model validity was established by comparing model-generated permeabilities with the permeability data from field and laboratory tests; by comparing fluid pathlines obtained from the SZ flow model with those inferred from hydrochemical data; and by comparing the upward gradient generated with the model with that observed in the field. This analysis is governed by the Office of Civilian Radioactive Waste Management (OCRWM) Analysis and Modeling Report (AMR) Development Plan ''Calibration of the Site-Scale Saturated Zone Flow Model'' (CRWMS M&O 1999a).