Monitoring Missions Research Articles

Problems of Monitoring Surface Waters in the Dnipro Basin

In Ukraine, the qualitative state of surface waters is unsatisfactory, especially in major water accumulation facilities of national importance, such as the Dnipro reservoirs. This situation necessitates changes in the state monitoring mission and regulatory policies in water use. Particular public importance lies in the objective assessment of the ecological and hydrological state of Ukraine's water bodies and waters, especially under the conditions of ecological-economic and military aggression, with respect to water bodies of national significance, such as the Dnipro reservoirs, primarily the Kremenchuk Reservoir. The study employs scientific methods of systemic analysis, including GIS analysis, generalization, and systematization, while considering synergistic approaches in the development of structural-logical schemes for monitoring systems in hydrology using the abduction method. The necessity of correlation analysis and the integration of surface water and soil monitoring systems has been investigated. For example, soil contamination with free nitrogen has led to a tenfold increase in nitrate concentrations in well water in the Poltava region over recent years. The analysis revealed insufficient observation points for surface water and a lack of systematic soil contamination surveys. It was demonstrated that monitoring of the Kremenchuk Reservoir should encompass not only the water quality of the reservoir itself but also the water-bearing streams, tributaries, and parts of the basin forming the reservoir, in accordance with the proposed structural-logical schemes. It was identified that only 0.1% of the 35 billion UAH allocated over the past 12 years to the Dnipro River rehabilitation program was spent on water monitoring, while water rental payments account for only 20% of state and municipal water management expenditures. A structural-logical scheme for the development of hydro-ecological monitoring of the water environment in part of the Dnipro basin has been proposed. Structural-logical schemes for the development of a spatial monitoring framework for the integral system of the Kremenchuk Reservoir's components have been suggested. The need to establish an information-analytical center for state water monitoring in Ukraine has been identified.

Prop-Plane — new convertible VTOL UAV as a combination of a longitudinal bicopter and a flying wing with a tilt-rotor powertrain

Vertical take-off and landing (VTOL) unmanned aircrafts are the newest and rapidly developing topic which is not only capable of improving Unmanned Aerial Vehicles (UAV) potential but also to create new use cases. This paper proposes a new convertible VTOL concept designed to obtain optimum flight characteristics for monitoring or flying over long objects. The distinctive feature of the proposed design is a combination of a flying wing with a longitudinal bicopter. The aircraft folds the wings down along the main axis of the aircraft during vertical take-offs and landings to descend the center of gravity and increase stability in bicopter mode. The convertible plane maximizes performance during horizontal flight while maintaining vertical take-off and landing capabilities.The design has been implemented in prototype, and the internal systems and the airframe have been designed and manufactured. As a result, the calculated technical characteristics of the UAV including wind resistance capability were described, the principal elements and components of the design were discussed, and the flight tests of the prototype created were conducted and results presented. Furthermore, the advantages and disadvantages of the concept are reviewed and further development of the project is discussed. The conducted work allows us to confirm the assumption that the developed concept can be used for real-world monitoring missions and to continue developing the concept for a full-scale UAV.

Cascade Model Predictive Control for Enhancing UAV Quadcopter Stability and Energy Efficiency in Wind Turbulent Mangrove Forest Environment

Unmanned aerial vehicle (UAV) modelling and control, particularly in quadrotors with high position-orientation coupling, present significant challenges for practical applications, such as environmental monitoring missions in windy mangrove forests. Conventional control strategies like the PID controller, often employed in simulations due to their simplicity, often underperform in real-world scenarios due to their linear assumptions. This research proposes a novel hierarchical cascaded model predictive control system for altitude, attitude, and battery efficiency for quadrotor in mangrove area. This control system addresses computational complexity by decomposing the overall MPC strategy into two distinct schemes, one for translational displacements and another for rotational movements, enhancing the UAV's resilience to wind turbulence, a significant disturbance factor in mangrove environments. Rigorous simulation and experiment test flight involving complex trajectory tracking and windy conditions demonstrate the proposed controller's superior performance compared to conventional PID controller, particularly in terms of stability, disturbance rejection, underscoring its potential for UAV applications in challenging environments.

Detecting the near-infrared afterglows of high-redshift gamma-ray bursts using CAGIRE

Transient sky astronomy is entering a new era with the advent of the Space Variable Objects Monitor mission (SVOM), successfully launched on 22 June 2024. The primary goal of SVOM is to monitor the hard X-ray sky searching for gamma-ray bursts (GRBs). On top of its on-board follow-up capabilities, SVOM will be backed by its ground segment composed of several facilities, including the near-infrared (NIR) imager CAGIRE. Mounted on the robotic telescope COLIBRI, it will be a unique instrument capable of performing fast follow-up of GRB afterglows in the J and H bands, ideal for capturing high-redshift (z$>$6) and/or obscured GRBs. This paper is aimed at estimating the performances of CAGIRE for GRB NIR afterglow detection based on the characteristics of the detector and the specificities of the COLIBRI telescope. Quickly fading GRB afterglows pose challenges that should be addressed by adapting observing strategies to the capabilities of CAGIRE. We used an end-to-end image simulator to produce realistic CAGIRE images, taking into account the results from the characterisation of the ALFA detector used by CAGIRE. We implemented a GRB afterglow generator that simulates infrared light curves and spectra based on published observation of distant GRBs (z$>$6). We retrieved the photometry of nine GRB afterglows in various scenarios covered by CAGIRE. Capturing afterglows as early as one minutes after the burst allows for the identification of a NIR counterpart in the brightest four events. When artificially redshifted even further away, these events remain detectable by CAGIRE up to z=9.6 in the J band and z=13.3 in H band, indicating the pioneering potential of CAGIRE in identifying the most distant GRBs to date.

In-flight Energy Calibration of the GECAM Gamma-ray Detectors

The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) mission is designed to monitor the Gamma-Ray Bursts (GRBs) associated with gravitational waves and other high-energy transient sources. The mission consists of two microsatellites which are planned to operate at the opposite sides of the Earth. Each GECAM satellite could detect and localize GRBs in about 8 keV–5 MeV with its 25 Gamma-Ray Detectors (GRDs). In this work, we report the in-flight energy calibration of GRDs using the characteristic gamma-ray lines in the background spectra, and show their performance evolution during the commissioning phase. Besides, a preliminary cross-calibration of energy response with Fermi GBM data is also presented, validating the energy response of GRDs.

TO THE ISSUE OF PROTECTING THE RIGHTS OF CHILDREN IN THE CONDITIONS OF MARTIAL LAW

The aim. The purpose of this study is to conduct an analysis of violations of children's rights in the context of armed conflict on the territory of Ukraine in order to determine ways to improve the regulatory and legal mechanisms for their protection. Materials and methods. To achieve the goal of the work, general scientific and special methods of scientific knowledge are used. The formal-legal method was applied to the analysis of legal acts regulating the protection of children's rights. Thanks to the application of this method, the formulation of legal norms, their legal technique, the conceptual and categorical apparatus was studied in order to clarify the content and essence of regulation, and the norms of international and national law were determined to identify gaps, collisions, and contradictions. The method of statistical analysis made it possible to determine the dynamics of the number of cases of abduction of children or their adoption. Results. During the research, it was established that russian aggression against Ukraine is accompanied by systematic violations of international law aimed at protecting the rights of the child, in particular the UN Convention on the Rights of the Child, the Geneva Conventions, and The Hague Conventions. According to the data of international monitoring missions, in the temporarily occupied territories of Ukraine numerous facts of violation of children's rights to life, protection from torture, personal integrity, dignity, safety, as well as rights to protection from sexual violence have been recorded. In addition, children are deprived of safe conditions for life, healthy development and realization of the right to education. Such systemic violations require an urgent response by the international community in the form of strengthening preventive measures to prevent further violations of childhood rights. Conclusions. As a result of the full-scale invasion and occupation of part of the territory of Ukraine, the number of cases of violation of children's rights has increased significantly. In particular, this concerns violations of the rights to life, personal integrity, protection of dignity, the right to protection from sexual violence and a number of others. Based on this, the problem of protecting children's rights is of great importance and determines the need to improve the existing mechanisms of legal protection at the national and international levels.

Uncertainty and Spatial Correlation in Station Measurements for mb Magnitude Estimation

Abstract The body-wave magnitude (mb) is a long-standing network-averaged, amplitude-based magnitude used to estimate the magnitude of seismic sources from teleseismic observations. The U.S. Geological Survey National Earthquake Information Center (NEIC) relies on mb in its global real-time earthquake monitoring mission. Although waveform modeling-based moment magnitudes are the modern standard to characterize earthquake size, mb is important because (1) in many cases, waveform modeling is not possible (e.g., low signal-to-noise events), (2) mb is applicable over a broad range of magnitudes, ∼M 4–7, and (3) there is a many decades-long history of estimating mb magnitudes. We use the NEIC Preliminary Determination of Epicenters earthquake catalog to investigate the uncertainty in NEIC station mb measurements. We show that mb measurements are spatially correlated, which can bias event mb, and we describe an empirical relation between this spatial correlation and station-to-station distance. We further describe an approach to mitigate bias from the spatial correlation. Accounting for the spatial covariance of observations can change the event mb from −0.15 to 0.07 mb units (10th to 90th percentile) for smaller events (mb≤4.5). These smaller events have the largest mb standard deviations ranging from 0.05 to 0.15 mb units (10th to 90th percentile).

Bioinspired Control Architecture for Adaptive and Resilient Navigation of Unmanned Underwater Vehicle in Monitoring Missions of Submerged Aquatic Vegetation Meadows.

Submerged aquatic vegetation plays a fundamental role as a habitat for the biodiversity of marine species. To carry out the research and monitoring of submerged aquatic vegetation more efficiently and accurately, it is important to use advanced technologies such as underwater robots. However, when conducting underwater missions to capture photographs and videos near submerged aquatic vegetation meadows, algae can become entangled in the propellers and cause vehicle failure. In this context, a neurobiologically inspired control architecture is proposed for the control of unmanned underwater vehicles with redundant thrusters. The proposed control architecture learns to control the underwater robot in a non-stationary environment and combines the associative learning method and vector associative map learning to generate transformations between the spatial and velocity coordinates in the robot actuator. The experimental results obtained show that the proposed control architecture exhibits notable resilience capabilities while maintaining its operation in the face of thruster failures. In the discussion of the results obtained, the importance of the proposed control architecture is highlighted in the context of the monitoring and conservation of underwater vegetation meadows. Its resilience, robustness, and adaptability capabilities make it an effective tool to face challenges and meet mission objectives in such critical environments.

High-z gamma-ray burst detection by SVOM/ECLAIRs: Impact of instrumental biases on the bursts’ measured properties

Context. Gamma-ray bursts (GRBs) can be detected at cosmological distances, and therefore can be used to study the contents and phases of the early Universe. The 4−150 keV wide-field trigger camera ECLAIRs on board the Space-based multi-band Variable Object Monitor (SVOM) mission, dedicated to studying the high-energy transient sky in synergy with multi-messenger follow-up instruments, has been adapted to detect high-z GRBs. Aims. Investigating the detection capabilities of ECLAIRs for high-redshift GRBs and estimating the impacts of instrumental biases in reconstructing some of the source measured properties, focusing on GRB duration biases as a function of redshift. Methods. We simulated realistic detection scenarios for a sample of 162 already observed GRBs with known redshift values as they would have been seen by ECLAIRs. We simulated them at redshift values equal to and higher than their measured value. Then we assessed whether they would be detected with a trigger algorithm resembling that on board ECLAIRs, and derived quantities, such as T90, for those that would have been detected. Results. We find that ECLAIRs would be capable of detecting GRBs up to very high redshift values (e.g. 20 GRBs in our sample are detectable within more than 0.4 of the ECLAIRs field of view for zsim > 12). The ECLAIRs low-energy threshold of 4 keV, contributes to this great detection capability, as it may enhance it at high redshift (z > 10) by over 10% compared with a 15 keV low-energy threshold. We also show that the detection of GRBs at high-z values may imprint tip-of-the-iceberg biases on the GRB duration measurements, which can affect the reconstruction of other source properties.

Greenhouse gas retrievals for the CO2M mission using the FOCAL method: first performance estimates

Abstract. The Anthropogenic Carbon Dioxide Monitoring (CO2M) mission is a constellation of satellites currently planned to be launched in 2026. CO2M is planned to be a core component of a Monitoring and Verification Support (MVS) service capacity under development as part of the Copernicus Atmosphere Monitoring Service (CAMS). The CO2M radiance measurements will be used to retrieve column-averaged dry-air mole fractions of atmospheric carbon dioxide (XCO2), methane (XCH4) and total columns of nitrogen dioxide (NO2). Using appropriate inverse modelling, the atmospheric greenhouse gas (GHG) observations will be used to derive United Nations Framework Convention on Climate Change (UNFCCC) COP 21 Paris Agreement relevant information on GHG sources and sinks. This challenging application requires highly accurate XCO2 and XCH4 retrievals. Three different retrieval algorithms to derive XCO2 and XCH4 are currently under development for the operational processing system at EUMETSAT. One of these algorithms uses the heritage of the FOCAL (Fast atmOspheric traCe gAs retrievaL) method, which has already successfully been applied to measurements from other satellites. Here, we show recent results generated using the CO2M version of FOCAL, called FOCAL-CO2M. To assess the quality of the FOCAL-CO2M retrievals, a large set of representative simulated radiance spectra has been generated using the radiative transfer model SCIATRAN. These simulations consider the planned viewing geometry of the CO2 instrument and corresponding geophysical scene data (including different types of aerosols and varying surface properties), which were taken from model data for the year 2015. We consider instrument noise and systematic errors caused by the retrieval method but have not considered additional error sources due to, for example, instrumental issues, spectroscopy or meteorology. On the other hand, we have also not taken advantage in this study of CO2M's MAP (multi-angle polarimeter) instrument, which will provide additional information on aerosols and cirrus clouds. By application of the FOCAL retrieval to these simulated data, confidence is gained that the FOCAL method is able to fulfil the challenging requirements for systematic errors for the CO2M mission (spatio-temporal bias ≤ 0.5 ppm for XCO2 and ≤ 5 ppb for XCH4).

Hexa-Propeller Airship for Environmental Surveillance and Monitoring in Amazon Rainforest

This paper proposes a new kind of airship actuator configuration for surveillance and environmental monitoring missions. We present the design and application of a six-propeller electrical airship (Noamini) with independent tilting propellers, allowing improved and flexible maneuverability. The vehicle has different combinations of differential propulsion and can be used in a two-, four- or six-motor configuration. We developed a high-fidelity airship simulator for the Noamini airship, which was used to test and validate a control/guidance approach. Incremental Nonlinear Dynamic Inversion (INDI) is used for the velocity/attitude control to follow a high-level L1 guidance reference in a simulated waypoint-tracking mission with wind and turbulence. The proposed framework will be soon implemented in the onboard control system of the Noamini, an autonomous airship for environmental monitoring and surveillance applications.

Some issues of the status and functioning of the United Nations human rights monitoring mission in Ukraine

Today, the United Nations plays a leading role in the development of international law and cooperation among the world's states. Member states have pledged to realize their rights and fulfill their obligations under the UN Charter. The main objectives of the UN are envisaged in Article 1 of the Charter, where the key provision relating to human rights is reflected in paragraph 3 of Article 1. According to it, the UN aims to achieve international cooperation in solving international problems of an economic, social, cultural and humanitarian character and in promoting and encouraging respect for human rights and fundamental freedoms for all without distinction of race, sex, language or religion [1]. As it can be seen, the Charter only calls on states parties to promote the protection of human rights, without establishing clear obligations to protect and guarantee them.
 Since 2014, i.e. since Russia launched its war against Ukraine, the aggressor has not stopped committing crimes against our country and our people. Russia's actions encroach not only on the sovereignty of our state, but also on human rights and freedoms. Under such circumstances, the international community cannot stand aside from these events. Many international human rights organizations have offices in Ukraine. Among them is the UN. On 31.07.2014, the Government of Ukraine and the Office of the United Nations High Commissioner for Human Rights signed an agreement on the deployment of a short-term UN human rights monitoring mission in Ukraine.
 The legal status of UN monitoring missions in legal science has not been the subject of a separate study. Certain aspects of the activities and competence of such missions have been considered in the works of such scholars as I.A. Shumilo [14], F. Megre [13], K. Boyle [12] and others, which are devoted to the coverage of international mechanisms for the protection of human rights and freedoms, the status of the UN General Assembly and the UN Human Rights Council. Therefore, the task set out in this article is to analyze and establish the specifics of the legal status of the UN Human Rights Monitoring Mission (hereinafter - the Mission), in particular, the one established for Ukraine, and the limits of the Mission's powers under the UN Charter, UN General Assembly resolutions, and international agreements between UN agencies and Ukraine. Therefore, the relevance of this article is beyond doubt. It has been established that the purpose of the Mission is to facilitate cooperation between the Government of Ukraine and the Office of the United Nations High Commissioner for Human Rights (hereinafter - OHCHR)[2] and it plays the role of a subsidiary mechanism for the protection of human rights and freedoms within the UN. The conclusions of the mission will undoubtedly serve as a convincing additional evidence base for Ukraine in international judicial and other bodies in protecting its interests and establishing the guilt of the Russian Federation for actions committed against our country.

Rovibrational Energies of 13C16O2 Determined with Kilohertz Accuracy.

Accurate spectroscopic data of carbon dioxide are widely used in many important applications, such as carbon monitoring missions. Here, we present comb-locked cavity ring-down saturation spectroscopy of the second most abundant isotopologue of CO2, 13C16O2. We determined the positions of 88 lines in three vibrational bands in the 1.6 μm region, 30011e/30012e/30013e-00001e, with an accuracy of a few kHz. Based on the analysis of combination differences, we obtained for the first time the ground-state rotational energies with kHz accuracy. We also provide a set of hybrid line positions for 150 13C16O2 transitions. The rotational energies (J < 50) in the 30013e vibrational state can be fitted by a set of rotational and centrifugal constants with deviations within a few kHz, indicating that the 30013e state is free of perturbations. These precise isotopic line positions will be utilized to improve the Hamiltonian model and quantitative remote sensing of carbon dioxide. Moreover, they will help to track changes in the carbon source and sink through isotopic analysis.

One small step for a robot, one giant leap for habitat monitoring: A structural survey of EU forest habitats with Robotically-mounted Mobile Laser Scanning (RMLS)

EU States are mandated by the 92/43/EEC Habitats Directive to generate recurring reports on the conservation status and functionality of habitats at the national level. This assessment is based on their floristic and, especially for forest habitats, structural characterization. Currently, habitat field monitoring efforts are carried out only by trained human operators. The H2020 Project “Natural Intelligence for Robotic Monitoring of Habitats – NI” aims to develop quadrupedal robots able to move autonomously in the unstructured environment of forest habitats. In this work, we tested the locomotion performance, efficiency and the accuracy of a robot performing structural habitat monitoring, comparing it with traditional field survey methods inside selected stands of Luzulo-Fagetum beech forests (9110 Annex I Habitat). We used a quadrupedal robot equipped with a Mobile Laser Scanning system (MLS), implementing for the first time a structural monitoring of EU forest habitats with a Robotically-mounted Mobile Laser Scanning (RMLS) platform. Two different scanning trajectories were used to automatically map individual tree locations and extract tree Diameter at Breast Height (DBH) from point clouds. Results were compared with field human measurements in terms of accuracy and efficiency of the survey. The robot was able to successfully execute both scanning trajectories, for which we obtained a tree detection rate of 100 %. Circular scanning trajectory performed better in terms of battery consumption, Root Mean Square Error (RMSE) of the extracted DBH (2.43 cm or 10.73 %) and prediction power (R2adj = 0.72, p < 0.001). The RMLS platform improved survey efficiency with 19.31 m2/min or 1.77 trees/min in comparison with 3.45 m2/min or 0.32 trees/min of traditional survey. Finally, a processing script was developed to allow the repeatability of RMLS surveys in similar habitat monitoring missions. In the future, a human-robotic monitoring framework might represent an accurate support for those repetitive and time-consuming activities in habitat monitoring, offering a valuable benefit for biodiversity conservation.

Capacity and establishment rules govern the number of nonnative species in communities of ground-dwelling invertebrates.

Nonnative species are a key agent of global change. However, nonnative invertebrates remain understudied at the community scales where they are most likely to drive local extirpations. We use the North American NEON pitfall trapping network to document the number of nonnative species from 51 invertebrate communities, testing four classes of drivers. We sequenced samples using the eDNA from the sample's storage ethanol. We used AICc informed regression to evaluate how native species richness, productivity, habitat, temperature, and human population density and vehicular traffic account for continent-wide variation in the number of nonnative species in a local community. The percentage of nonnatives varied 3-fold among habitat types and over 10-fold (0%-14%) overall. We found evidence for two types of constraints on nonnative diversity. Consistent with Capacity rules (i.e., how the number of niches and individuals reflect the number of species an ecosystem can support) nonnatives increased with existing native species richness and ecosystem productivity. Consistent with Establishment Rules (i.e., how the dispersal rate of nonnative propagules and the number of open sites limits nonnative species richness) nonnatives increased with automobile traffic-a measure of human-generated propagule pressure-and were twice as common in pastures than native grasslands. After accounting for drivers associated with a community's ability to support native species (native species richness and productivity), nonnatives are more common in communities that are regularly seasonally disturbed (pastures and, potentially deciduous forests) and those experiencing more vehicular traffic. These baseline values across the US North America will allow NEON's monitoring mission to document how anthropogenic change-from disturbance to propagule transport, from temperature to trends in local extinction-further shape biotic homogenization.

Detail and structural design of a fixed-wing BWB UAV

The current study focuses on the development of a prototype BWB UAV for highway traffic monitoring by supporting a Cooperative Intelligent Transport System (C-ITS). This system allows the monitoring of traffic conditions at large roads and highways. Having determined the mission requirements and concluded the aerodynamic conceptual and preliminary design phases, high fidelity CFD simulations are performed, aiming to calculate the key aerodynamic and stability characteristics of the platform and to optimize its performance throughout the mission. More specifically, regarding the aerodynamic vehicle design, results concerning the calculation of stability derivatives, control surfaces sizing, trim analysis and flight envelope (V-n diagram) are presented, along with the respective methodologies. Considering the structural design of the aircraft, a combination of layout, FE simulations and parameterized design tools were employed, allowing the design and sizing of the skin and the internal structural parts. The parts are mainly made of composite and additively manufactured nylon materials. Coupled interaction loops are conducted among the aerodynamic and structural analyses to optimize the overall performance of the aerial vehicle, maximizing the aerodynamic efficiency, and reducing the structural weight. Finally, the study is concluded by the presentation of the manufactured prototype of the UAV, which satisfies all the structural, aerodynamic, stability and performance requirements for the established highway traffic monitoring mission.

Underwater Vehicle Path Planning Based on Bidirectional Path and Cached Random Tree Star Algorithm

Underwater autonomous path planning is a critical component of intelligent underwater vehicle system design, especially for maritime conservation and monitoring missions. Effective path planning for these robots necessitates considering various constraints related to robot kinematics, optimization objectives, and other pertinent factors. Sample-based strategies have successfully tackled this problem, particularly the rapidly exploring random tree star (RRT*) algorithm. However, conventional path-searching algorithms may face challenges in the marine environment due to unique terrain undulations, sparse and unpredictable obstacles, and inconsistent results across multiple planning iterations. To address these issues, we propose a new approach specifically tailored to the distinct features of the marine environment for navigation path planning of underwater vehicles, named bidirectional cached rapidly exploring random tree star (BCRRT*). By incorporating bidirectional path planning and caching algorithms on top of the RRT*, the search process can be expedited, and an efficient path connection can be achieved. When encountering new obstacles, ineffective portions of the cached path can be efficiently modified and severed, thus minimizing the computational workload while enhancing the algorithm’s adaptability. A certain number of simulation experiments were conducted, demonstrating that our proposed method outperformed cutting-edge techniques like the RRT* in several critical metrics such as the density of path nodes, planning time, and dynamic adaptability.

Adaptive sensor management for UGV monitoring based on risk maps

Because of the recent advances in sensor technology, unmanned ground vehicles (UGVs) are equipped with various high-performance sensors to improve their mission performance. The energy consumption of the sensors is a critical issue because most UGVs operate on rechargeable batteries while conducting their missions. In particular, efficient sensing has become a crucial challenge due to the growing demand for advanced intelligent monitoring missions. However, while previous studies have focused on power consumption models for vehicle locomotion, they have not fully addressed the high energy consumption of sensors.This study proposes an adaptive sensor-management algorithm to address the critical issue of energy consumption by considering the monitoring and navigation sensors that are widely used in UGV monitoring. After characterizing the proposed adaptive sensor-management strategy based on a risk map composed of monitoring and saving zones, we present a power consumption model to quantify the energy savings of the sensors. Furthermore, the optimal interval was derived to minimize power consumption during UGV monitoring. The proposed algorithm can minimize the energy consumption by adjusting the optimal interval according to the mission environment. We demonstrate the results of our analysis through various evaluations.

Wideband Omnidirectional Antenna Featuring Small Azimuthal Gain Variation.

Wideband omnidirectional antennas are essential components in radio monitoring and communication systems, enabling the reception of signals from all directions over a wide bandwidth. This paper presents a novel wideband omnidirectional antenna design that achieves a 1-dB gain variation across its azimuthal plane within a bandwidth of 1.8 GHz to 7.77 GHz. The antenna's exceptional performance is attributed to two flower-bud-shaped monopoles that, through pattern superposition, generate a wideband omnidirectional radiation pattern. Analysis shows that the use of a circular ground plane also reduces the azimuthal gain variation. Additionally, an embedded matching structure integrated into the antenna's base enhances the impedance bandwidth without compromising its compact size. Analytical investigations demonstrate that the matching structure effectively behaves as a five-order LC circuit, explaining its wideband matching capabilities. Furthermore, structural modifications effectively reduce side lobe levels, ensuring minimal interference. Experimental measurements corroborate the antenna's omnidirectional radiation pattern and confirm that the azimuthal gain variation remains within 1-dB throughout its bandwidth, while maintaining an S11 below -10 dB from 1.8 GHz to 7.7 GHz. The antenna's bandwidth overlaps with the spectrum intensively used in mobile communication technologies, such as LTE, Bluetooth, and IEEE 802.11be, as well as radiolocation applications, making it a promising choice for unmanned aerial vehicles conducting communication and radio monitoring missions.

Development of Mobile App to Enable Local Update on Mapping API: Construction Sites Monitoring through Digital Twin

Unmanned ground vehicles (UGVs) have emerged as a promising solution for reconnaissance missions, overcoming labor cost, frequency, and subjectivity issues associated with manual procedures. However, for dynamic environments such as construction sites, the constantly changing conditions hinder a manager from planning the UGV’s paths. For an autonomous monitoring mission, the path planning should be dealt with by having a map with the site’s most recent scene. In this study, we develop a mobile app capable of local map updates by overlaying an image on a mapping API (e.g., Google Maps) hence working as a digital twin capable of creating a dynamic representation of the updated terrain over the mapping API. UGV operators can draw a path on such an updated construction scene using a tablet PC or smartphone. Discrete GPS information (e.g., latitudinal, and longitudinal) is executed for the UGV’s controller. In the overlaying procedure, the homographic relation between the image and map is automatically computed and then projected. We successfully demonstrated the capabilities of the technique with two construction sites and a soccer field using images from the ground and satellite, respectively. The error generation is quantitatively measured and analyzed.