Defense Mission Research Articles

Design of a high-stability heterogeneous clock system for small satellites in LEO

We describe our investigation into the performance of low-power heterogeneous timing systems for small satellites, using real GPS observables from the GRACE Follow-On mission. Small satellites have become capable platforms for a wide range of commercial, scientific and defense missions, but they are still unable to meet the needs of missions that require precise timing, on the order of a few nanoseconds. Improved low-power onboard clocks would make small satellites a viable option for even more missions, enabling radio aperture interferometry, improved radio occultation measurements, high altitude GPS navigation, and GPS augmentation missions, among others. One approach for providing improved small satellite timekeeping is to combine a heterogeneous group of oscillators, each of which provides the best stability over a different time frame. A hardware architecture that uses a single-crystal oscillator, one or more Chip Scale Atomic Clocks (CSACs) and the reference time from a GPS receiver is presented. The clocks each contribute stability over a subset of timeframes, resulting in excellent overall system stability for timeframes ranging from less than a second to several days. A Kalman filter is used to estimate the long-term errors of the CSACs based on the CSAC-GPS time difference, and the improved CSAC time is used to discipline the crystal oscillator, which provides the high-stability reference clock for the small satellite. Simulations using GRACE-FO observations show time error standard deviations for the system range from 2.3 ns down to 1.3 ns for the clock system, depending on how many CSACs are used. The results provide insight into the timing performance which could be achieved on small LEO spacecraft by a low power timing system.

A Review on Cooperative Robotic Arms with Mobile or Drones Bases

This review paper focuses on cooperative robotic arms with mobile or drone bases performing cooperative tasks. This is because cooperative robots are often used as risk-reduction tools to human life. For example, they are used to explore dangerous places such as minefields and disarm explosives. Drones can be used to perform tasks such as aerial photography, military and defense missions, agricultural surveys, etc. The bases of the cooperative robotic arms can be stationary, mobile (ground), or drones. Cooperative manipulators allow faster performance of assigned tasks because of the available “extra hand”. Furthermore, a mobile base increases the reachable ground workspace of cooperative manipulators while a drone base drastically increases this workspace to include the aerial space. The papers in this review are chosen to extensively cover a wide variety of cooperative manipulation tasks and industries that use them. In cooperative manipulation, avoiding self-collision is one of the most important tasks to be performed. In addition, path planning and formation control can be challenging because of the increased number of components to be coordinated.

R&D priority-setting for global catastrophic risks: The case of the NASA planetary defense mission

"Mission-oriented" public research organizations invest in R&D to improve decision-making around complex policy problems from climate change to asteroid impacts, thus producing public value. However, the estimation of benefits produced by such R&D projects is notoriously difficult to predict and measure - a challenge that is magnified for global catastrophic risks (GCRs). GCRs are highly uncertain risks that may pose enormous negative consequences for humanity. This article explores how public research organizations systematically reduce key uncertainties associated with GCRs. Building off of recent literature highlighting the organizational and political factors that influence R&D priority-setting at public research organizations, this article develops an analytical framework for explaining R&D priority-setting outcomes that integrates the key stages of decision analysis with organizational and political dynamics identified in the literature. This framework is then illustrated with a case study of the NASA Planetary Defense Coordination Office, which addresses the GCR of near-Earth object (asteroid and comet) impacts. The case study reveals how organizational and political factors interact with every stage in the R&D priority-setting process - from initial problem definition to project selection. Lastly, the article discusses the extent to which the case study can inform R&D priority-setting at other public organizations, particularly those addressing GCRs.

The U.S. Failure in Afghanistan and the Future of World Order

The U.S. withdrawal from Afghanistan is the culmination of a shift in the strategic priorities of the United States in its relationship with the rest of the world that began with the Obama administration. In contrast to George W. Bush’s attempt to challenge the spread of Islamist violence by promoting the establishment of liberal values in the Middle East, the Obama, Trump, and Biden administrations have given up on that project in order to focus on the narrower defensive mission of making sure that the United States is not directly affected by terrorism. According to this policy, the spread of Islamist ideology in the Middle East, Africa, and Europe is no longer a significant U.S. foreign policy concern. Rather, the focus will be on suppressing the most virulent examples of this ideology, such as the Islamic State, while tolerating and even collaborating with others, such as Iran, Pakistan, and now perhaps even the Taliban.

Guerra y milicias en el Siglo de las Luces

A lo largo del siglo xviii las milicias se consolidaron como una fuerza que complementó a los ejércitos permanentes, tanto cumpliendo misiones de defensa del territorio como constituyendo una fuerza militar de reserva a la que recurrir siempre que la situación lo requiriese. En oposición a sus predecesoras de los siglos anteriores, estas estuvieron organizadas por una regulación común y controladas directamente por la Corona, lo que constituyó su principal garantía de supervivencia frente a sus detractores. En este artículo se expone la creación, organización y evolución de las milicias que se establecieron en la Monarquía de España durante el Siglo de las Luces, con especial atención a la provincial, y, además, se trata de rebatir las críticas vertidas contra estos cuerpos durante su existencia, así como en tiempos posteriores.

Capturing a spacecraft around a flyby asteroid using Hamiltonian-structure-preserving control

The potentially hazardous asteroid is not only the target of planetary defense missions but also an ideal one for scientific exploration of near-Earth objects due to minimal launching budget during its close encounter with Earth. The flyby segment of asteroid shows to be hyperbolic in an Earth-centred inertial frame. To guide the spacecraft captured by the asteroid under the common Earth's gravity, the Hamiltonian-structure-preserving (HSP) controller, based only on the feedback of relative positions, is constructed to transform the topological structure of the equilibrium point from hyperbolic to elliptic. On account of the small mass of flyby asteroid, a hyperbolic two-body model is used to derive the form of controller. The controller is also proved to work effectively in the hyperbolic three-body model. Critical control gains for both transient and long-term stabilities are investigated, as well as the controlled frequencies caused by different gains. To avoid collision with an asteroid, the artificial potential function (APF) is employed to improve the HSP controller.

Cooperative Task Assignment of a Heterogeneous Multi-UAV System Using an Adaptive Genetic Algorithm

The cooperative multiple task assignment problem (CMTAP) is an NP-hard combinatorial optimization problem. In this paper, CMTAP is to allocate multiple heterogeneous fixed-wing UAVs to perform a suppression of enemy air defense (SEAD) mission on multiple stationary ground targets. To solve this problem, we study the adaptive genetic algorithm (AGA) under the assumptions of the heterogeneity of UAVs and task coupling constraints. Firstly, the multi-type gene chromosome encoding scheme is designed to generate feasible chromosomes that satisfy the heterogeneity of UAVs and task coupling constraints. Then, AGA introduces the Dubins car model to simulate the UAV path formation and derives the fitness value of each chromosome. In order to comply with the chromosome coding strategy of multi-type genes, we designed the corresponding crossover and mutation operators to generate feasible offspring populations. Especially, the proposed mutation operators with the state-transition scheme enhance the stochastic searching ability of the proposed algorithm. Last but not least, the proposed AGA dynamically adjusts the number of crossover and mutation populations to avoid the subjective selection of simulation parameters. The numerical simulations verify that the proposed AGA has a better optimization ability and convergence effect compared with the random search method, genetic algorithm, ant colony optimization method, and particle search optimization method. Therefore, the effectiveness of the proposed algorithm is proven.

Quantum Science and Quantum Technology: Progress and Challenges

Quantum computing has the potential to offer new capabilities and quantum computers will achieve breakthroughs in finance, cybersecurity, medical science and healthcare, defense and military missions, etc. Progress in quantum science and quantum technology are introduced in this paper that specifically include quantum computers, quantum devices, quantum processing units (QPU), quantum artificial intelligence (QAI), quantum machine learning (QML), quantum cloud computing, quantum network and communication, quantum teleportation, quantum experiment satellite, quantum cryptography, and quantum key distribution (QKD). Some challenges are also presented.

Cooperative Multiple Task Assignment of Heterogeneous UAVs Using a Modified Genetic Algorithm with Multi-type-gene Chromosome Encoding Strategy

The cooperative multiple task assignment problem (CMTAP) of heterogeneous fixed-wing unmanned aerial vehicles (UAVs) performing the Suppression of Enemy Air Defense (SEAD) mission against multiple ground stationary targets is studied in this paper. The CMTAP is a NP-hard combinatorial optimization problem, which faces many challenges like problem scale, heterogeneity of UAVs (different capability and maneuverability), task coupling and task precedence constraints. To address this issue, we proposed a modified genetic algorithm (GA) with multi-type-gene chromosome encoding strategy. Firstly, the multi-type-gene encoding scheme is raised to generate feasible chromosomes that satisfy the UAV capability, task coupling and task precedence constraints. Then, Dubins car model is adopted to calculate the mission execution time (objective function of CMTAP model) of each chromosome, and make each chromosome conform to the UAV maneuverability constraint. To balance the searching ability of algorithm and the diversity of population, we raise the modified crossover operator and multiple mutation operators according to the multi-type-gene chromosome encoding. The simulation results demonstrate that the modified GA has better optimization performance compared with random search method, ant colony optimization method and particle search optimization method.

Collaborative Defense with Multiple USVs and UAVs Based on Swarm Intelligence

Modern defense systems are developing towards systematization, intellectualization and automation, which include the collaborative defense system on the sea between multiple unmanned surface vehicles (USVs) and unmanned aerial vehicles (UAVs). UAVs can fly in high altitude and collect marine environment information on patrolling. Furthermore, UAVs can plan defense paths for USVs to intercept intruders with full-assignment or reassignment strategies aiming at maximum overall benefits. Thus, we propose dynamic overlay reconnaissance algorithm based on genetic idea (GI-DORA) to solve the problem of multi-UAV multi-station reconnaissance. Moreover, we develop continuous particle swarm optimization based on obstacle dimension (OD-CPSO) to optimize defense path of USVs to intercept intruders. In addition, under the designed defense constraints, we propose dispersed particle swarm optimization based on mutation and crossover (MC-DPSO) and real-time batch assignment algorithm (RTBA) in emergency for formulating combat defense mission assignment strategy in different scenarios. Finally, we illustrate the feasibility and effectiveness of the proposed methods.

Dynamics and motion patterns of a k-capture game with attraction-repulsion interaction

In this paper, we propose and formulate a k-capture game, where a single intruder tries to reach a stationary target that is protected by a swarm of defenders, and the defenders try to intercept (capture) the intruder by a synchronous defense with k-capture (at least k defenders have to synchronously reach the intruder's location to capture it). Assume that the defenders have no explicit task collaboration, no spatio-temporal memory and no speed advantage. Three general collective motions with simple attraction-repulsion interaction between defender pairs are introduced to investigate the dynamics and motion patterns of the k-capture game. The results suggest that such system with merely local spacial attraction-repulsion interaction of defenders already shows very rich and even unexpected motion patterns, including the boundary defense motion pattern, the intruder-follower-and-rounded-up motion pattern, the periodic motion pattern, and the multiple small cohesive groups motion pattern. The results also show that the multiple small cohesive groups motion pattern seems to be the most effective defense motion since the power of the collective is better used. The study of k-capture game provides an insight into the defense-intrusion interaction in nature. This approach can also provide elegant insights for artificial systems, such as escort mission for aircraft, defense mission for military base or territorial boundaries by a swarm of autonomous vehicles.

Torres de vigilancia en la costa del antiguo reino de Granada (S XV-XVIII)

A lo largo de nuestras costas mediterráneas nos encontramos con una serie continua de torres de diferentes formas situadas en altozanos que dominan el mar, separadas, unas de otras, a la distancia suficiente para que puedan verse y comunicarse entre sí con facilidad. Son torres de vigilancia o torres almenaras, que detectan la aproximación de embarcaciones intrusas que llegan del norte de África con intenciones poco pacíficas. A estas torres –patrimonio histórico, cultural y turístico– que se construyeron entre los siglos XV y XVIII, se refiere este artículo en el que de forma somera se describe su importancia defensiva a lo largo del tiempo, su organización, su tipología, materiales empleados en su construcción y su conservación.

Optimal SUAS Path Planning in Three-Dimensional Constrained Environments

Small Unmanned Aircraft Systems have grown in autonomy and capability and continue to complement Department of Defense mission objectives. Teaming unmanned aircraft with manned vehicles can expand mission profiles and reduce risk to human life. To fully leverage unmanned systems, vehicles must be efficient and autonomous in path planning development. The work herein explores direct orthogonal collocation optimal control techniques combined with fast geometric path planning algorithms to reduce computation time and increase solution accuracy for small unmanned aircraft systems path planning missions. Previous work in the two-dimensional plane demonstrated a methodology to provide optimal flight paths through defined simplex corridors and simplified the optimal control parameter bounds by formulating the problem in the barycentric coordinate system. These methodologies are extended in this paper for three-dimensional flight and are solved with two different formulations for flight in an urban environment. The first formulation solves the constrained optimal control problem using a single phase while modeling the building constraints with superquadric functions. The second formulation implements the simplex methodology, eliminating polygonal constraints from the search domain, and solving the optimal path in a multiple phase approach. Results illustrate the benefits gained in computation time and accuracy when implementing simplex methods into the optimal control design and provide a foundation for closing the gap to real-time, onboard operations for unmanned vehicle path planning.

Comprehensive Damage Assessment of Cyberattacks on Defense Mission Systems

Comprehensive Damage Assessment of Cyberattacks on Defense Mission Systems

Boeing's Autonomous Military Aircraft

Boeing will build a self-propelled military aircraft to accompany US combat aircraft during missions. Boeing's autonomous airplane will achieve superior flying performance to those pilots even with the most modern aircraft. If technology advances and becomes more accessible to civilians, why would not this happen in the military domain? US, Russian, Australian and British armies have already been using advanced technology for decades were civilians just dream, these technologies being totally secret and forbidden to the general public and mass media. Boeing, which manufactures commercial and military aircraft, wants to revolutionize the art of war and introduce a state-of-the-art, self-propelled aircraft into the battlefield to adapt to a variety of complex military missions. They called it the Boeing Airpower Teaming System because it will team up well with military pilots during reconnaissance missions or even hostility or defensive missions. This autonomous airplane will play the role of additional help designed to significantly reduce the risks to which soldiers are often exposed. The stand-alone aircraft can be sent both on reconnaissance missions and for attack operations (either for defense or for the removal of targets considered terrorist). He will be able to intercept the enemy in good time and to annihilate it. It will be manufactured in Australia and it will have a length of more than 11 meters and Boeing promises autonomy of over 3,700 kilometers (2,000 nautical miles). Obviously, the company will not only produce for Americans or Australians. Any government will be able to purchase the autonomous airplane if it allows it (at least theoretically, because sales of such products are basically also with special political agreements). It is very likely that in the future, we will not even have much need for soldiers if the missions are carried out by autonomous airplanes or robots. Good news, as democracies have come to pay citizens to motivate them to become soldiers.

Adaptive Weapon-to-Target Assignment Model Based on the Real-Time Prediction of Hit Probability

Weapon-to-target assignment (WTA), which minimizes the damage to our forces by launching interceptor missiles (weapons) against ballistic missiles of the enemy (targets), is a critical decision-making problem of ballistic missile defense missions. The primary objective is to launch an interceptor with a high hit probability for each target. The existing research on WTA assumes that the hit probability is known before an engagement regardless of whether the probability varies during the engagement. However, the hit probability in actual engagement situations is a time-dependent variable that changes in accordance with the flight states of the target and interceptor that are unknown in advance. Therefore, a rolling horizon-based decision approach is necessary. In this research, we propose an adaptive WTA (AWTA) model that makes WTA decisions at each radar scanning time based on the hit probability predicted using radar information about the engagement situation-for each target, an interceptor with a hit probability higher than a threshold is launched, thereby maximizing the total hit result. A machine learning model is suggested to learn the probabilistic relationship between the flight states and hit results, and this model is embedded in the solution procedure of the AWTA model. The performance of the AWTA model is evaluated via a simulation-based experiment, and the results confirm that the proposed AWTA model is appropriate for real-time engagement situations.

Europejska Strategia Bezpieczeństwa 2003–2008. Analiza politologiczna

In 2003, the Council of Europe, the highest political organ of the European Union, resolved to adopt the European Security Strategy. This document outlined three fundamental objectives for the EU: stability and good governance in the area of the EU’s closest neighbors; creating an international order that would be based not only on bilateral relations, but primarily on efficient multilateral relations; and preventing threats, whether new or traditional. The Strategy assumed that the EU would take the responsibility for international security both in the realm of ‘peace keeping’ (peace and defensive missions) and ‘peace-making’ (peace and offensive missions). Defining the threats that the European Union needs to defy, the Strategy enumerates local conflicts, terrorism, the proliferation of weapons of mass destruction and their potential use against the territory of the EU and its member states, collapsing states, and conflicts breaking out in such states and their neighborhood, as well as organized crime. The assessment of numerous threats to internal and external security, presented in the European Security Strategy, remains up-to-date. There have also emerged new threats for Europe that result from the need to ensure energy security, primarily with respect to the diversification of energy sources. The significance of climate change to international security has increased. The same applies to IT security or piracy. The EU has been rather anxious about the intensification of frozen conflicts, in particular the outbreak of war between Russia and Georgia. The Polish Ministry of Foreign Affairs has indicated that the enlargement process is a significant stabilizing factor in the EU neighborhood. Fundamental importance is also attached to the review of cooperation principles with the USA, the crucial role of the UN in the international system, and cooperation with regional organizations, such as the African Union. There is also the need to develop a strategic partnership with NATO, in particular in terms of operational cooperation. Another key factor in the strengthening of the EU’s global position is the development of a civil and military crisis response system.

A First Catalog of Variable Stars Measured by the Asteroid Terrestrial-impact Last Alert System (ATLAS)

Abstract The Asteroid Terrestrial-impact Last Alert System (ATLAS) carries out its primary planetary defense mission by surveying about 13,000 deg2 at least four times per night. The resulting data set is useful for the discovery of variable stars to a magnitude limit fainter than r ∼ 18, with amplitudes down to 0.02 mag for bright objects. Here, we present a Data Release One catalog of variable stars based on analyzing the light curves of 142 million stars that were measured at least 100 times in the first two years of ATLAS operations. Using a Lomb–Scargle periodogram and other variability metrics, we identify 4.7 million candidate variables. Through the Space Telescope Science Institute, we publicly release light curves for all of them, together with a vector of 169 classification features for each star. We do this at the level of unconfirmed candidate variables in order to provide the community with a large set of homogeneously analyzed photometry and to avoid pre-judging which types of objects others may find most interesting. We use machine learning to classify the candidates into 15 different broad categories based on light-curve morphology. About 10% (427,000 stars) pass extensive tests designed to screen out spurious variability detections: we label these as “probable” variables. Of these, 214,000 receive specific classifications as eclipsing binaries, pulsating, Mira-type, or sinusoidal variables: these are the “classified” variables. New discoveries among the probable variables number 315,000, while 141,000 of the classified variables are new, including about 10,400 pulsating variables, 2060 Mira stars, and 74,700 eclipsing binaries.

PERENCANAAN PEMBANGUNAN KEKUATAN MARITIM INDONESIA UNTUK MENGHADAPI TANTANGAN TAHUN 2020

<p><em>Problems of Indonesian maritime force development planning is inseparable from the role of government to support the development of maritime forces. In accordance with geography constellation as the largest archipelago in the world according to UNCLOS 1982, Indonesian economic development currently the largest in Southeast Asia and number 16 in the world with 6.4% gross domestic product (year on year). In this sense, it is time for implementing maritime force development based on maritime perspective and state defense as a whole integrated. Regardless of budget required by the military to implement its vision and mission of defense, the state has to be able to fulfill it and is able to offset foreign policy of the so-called Indo-pacific region in 2020. </em><strong></strong></p><p><strong><em>Keywords:</em></strong><em> Defense, Maritime Defense, Military Reformation, Military Innovation.</em></p>

International coordination on planetary defence: The work of the IAWN and the SMPAG

Space capabilities play a crucial role in ensuring human security. One of the threats coming from space is the possible damage to our assets by an asteroid or comet impact. As demonstrated by the object entering the Earth's atmosphere over Chelyabinsk, Russia, in February 2013, the threat of an asteroid or comet impact is a real and global issue demanding development of an international response. Addressing such a hazard, by first identifying those objects that pose a threat to enable planning a corresponding mitigation campaign, require international coordination. The United Nations Member States, especially those with capabilities to engage in a possible planetary defence mission, already share a number of common activities in this field. This paper outlines the progress made in the implementation of recommendations for an international response to the NEO impact threat, as agreed under the auspices of the United Nations (UN) Committee on the Peaceful Uses of Outer Space (COPUOS) and welcomed by the UN General Assembly in its resolution 68/75 of December 2013. The recommendations provide for a coordinated international response to a possible NEO threat. They aim at ensuring international information-sharing in discovering, monitoring and physically characterizing potentially hazardous NEOs with a view that all countries, in particular developing countries with limited capacity in predicting and mitigating a NEO impact, are aware of potential threats. They emphasize the need for an effective emergency response and disaster management in the event of a discovered NEO impact threat. The International Asteroid Warning Network (IAWN) and the Space Mission Planning Advisory Group (SMPAG), which are the two entities established in 2014 as a result of the UN-endorsed recommendations, are important mechanisms at the global level for strengthening the coordination in the area of planetary defence. The United Nations Office for Outer Space Affairs (UNOOSA) acts as secretariat to SMPAG and works with both IAWN and SMPAG in addressing this global issue. In the event of a credible impact prediction, warnings would be issued by the IAWN, the SMPAG would propose mitigation options and implementation plans for consideration to the Member States. The goal is the global protection of the eco-system, of human beings and their properties on Earth, and of the civilization of humankind from a devastating asteroid impact. The current paper outlines the work of the IAWN and the SMPAG towards a road-map for planetary defence at the global level, including agreements on initial criteria and thresholds for impact threat response actions, consideration of mitigation mission types and technologies and mapping of threat scenarios to mission types as well as developing a plan for action in case a credible threat is discovered. The paper also reflects on how to convey information about the NEO impact warnings and associated impact probabilities to the public and governmental decision-makers as part of the agreed communications guidelines, which are another important pillar in the work of the IAWN.