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This thesis work has been part of an effort to improve the after-action reviews of the air combat simulator training sessions conducted at the Swedish Air Force Combat Simulation Centre (FLSC). Initial studies identified three main needs regarding the evaluation of air-to-air missile shots during beyond-visual-range combat simulation. These needs included an improved detection of where and when in the simulation playback a missile shot took place, a collected view of flight parameters to prevent confusion and cross-referencing between the various displays, as well as the ability to review an aircraft’s flight parameters over time in order to discuss alternative shooting opportunities or maneuvering patterns. To fulfill these three needs, design studies were performed iteratively in collaboration with staff at the FLSC. This work has resulted in a design proposal with a prototype based on the design guidelines and recommendations of the study's participants. The purpose of the visualization is to provide support for instructors and promote the individual learning of pilots. Hopefully, this can ultimately help in answering the question regarding why a missile missed its target. For instructors and air units such aids could mean that operating errors can be more easily identified and also form a basis for discussion during the assessment briefings. / Detta examensarbete har haft som syfte att förbättra utvärderingen av luftstridssimuleringar som bedrivs vid det svenska flygvapnets luftstridssimuleringscentrum, FLSC. Inledande studier identifierade tre huvudsakliga behov för utvärderingen av flygplansburna robotskott avfyrade mot luftmål utom synhåll, på långa avstånd. Dessa behov inkluderar en förbättring när det gäller att upptäcka var och när i en simuleringsuppspelning som ett robotskott har skett, en samlad vy över flygparametrar för att förhindra förvirring och korsreferering mellan olika skärmar, samt möjligheten att utvärdera ett flygplans flygparametrar över tid för att kunna diskutera alternativa avfyrningsmöjligheter eller manövreringsmönster. För att fylla dessa tre behov har iterativa designstudier utförts i samarbete med personalen på FLSC. Detta har resulterat i ett designförslag med en prototyp baserad på de designriktlinjer och -rekommendationer som studiens deltagare delgett. Syftet med visualiseringen är att ge stöd till instruktörer och främja piloters individuella inlärning. Förhoppningsvis kan detta i slutändan bidra till att svara på frågan om varför en robot missade sitt mål. För instruktörer och flygförband kan ett sådant hjälpmedel underlätta identifiering av felmanövreringar och även ligga till grund för värdefulla diskussioner under analysen av genomförda luftsstridsimuleringar.

International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / Since the Gulf War, there has been significant interest in Theater Missile Defense (TMD) resulting in funding growth from tens of millions of dollars at the time of the Gulf War to $1.7 Billion in 1994. The Ballistic Missile Defense Organization (BMDO) has developed a Theater Missile Defense test and evaluation program that will assess technological feasibility and the degree to which system functionality and performance meet technical and operational requirements. The complexity of the TMD program necessitates a comprehensive test program which includes flight testing, ground testing, and modeling and simulation. This article will provide and overview the requirements and capabilities needed to satisfy these requirements. The data processing, and telemetry communities will play a major role in providing the expertise to support the development of the nation’s future Theater Missile Defense capabilities.

Approved for public release, distribution is unlimited / India has made a concerted effort to upgrade its ISR, precision strike, and missile defense capabilities as it competes with China and Pakistan for regional power. The Phalcon Airborne Warning and Control System, Su-30MKI fighter-bomber aircraft, and S-300PMU surface-to-air missile system are some examples of the new capabilities India is acquiring. I argue that if India continues its military modernization, Pakistan will become more insecure. The increase in the conventional military capabilities gap will likely upset the existing balance of power in South Asia, leading to a regional arms race, lowering the nuclear threshold, and increasing instability in the region. The strategic stability/tactical instability paradox that exists between two nuclear countries may lead them to engage in "small" wars. India's increasing military capabilities may encourage it to conduct a preventive strike against Pakistan. In such a climate, a regional arms race eventually may lead Pakistan to establish a "hair-trigger" nuclear posture. India's effort to achieve a significantly superior conventional military force over Pakistan paradoxically may reduce Indian security by causing greater instability, and possibly lead to nuclear war. Regional stability is enhanced to the extent that there is a rough conventional military balance between India and Pakistan. / Lieutenant, United States Navy

The main body of this thesis consists of six appended papers. In the  first two, different  cooperative surveillance problems are considered. The second two consider different aspects of the trajectory planning problem, while the last two deal with observer design for mobile robotic and Euler-Lagrange systems respectively.In Papers A and B,  a combinatorial optimization based framework to cooperative surveillance missions using multiple Unmanned Ground Vehicles (UGVs) is proposed. In particular, Paper A  considers the the Minimum Time UGV Surveillance Problem (MTUSP) while Paper B treats the Connectivity Constrained UGV Surveillance Problem (CUSP). The minimum time formulation is the following. Given a set of surveillance UGVs and a polyhedral area, find waypoint-paths for all UGVs such that every point of the area is visible from  a point on a waypoint-path and such that the time for executing the search in parallel is minimized.  The connectivity constrained formulation  extends the MTUSP by additionally requiring the induced information graph to be  kept recurrently connected  at the time instants when the UGVs  perform the surveillance mission.  In these two papers, the NP-hardness of  both these problems are shown and decomposition techniques are proposed that allow us to find an approximative solution efficiently in an algorithmic manner.Paper C addresses the problem of designing a real time, high performance trajectory planner for an aerial vehicle that uses information about terrain and enemy threats, to fly low and avoid radar exposure on the way to a given target. The high-level framework augments Receding Horizon Control (RHC) with a graph based terminal cost that captures the global characteristics of the environment.  An important issue with RHC is to make sure that the greedy, short term optimization does not lead to long term problems, which in our case boils down to two things: not getting into situations where a collision is unavoidable, and making sure that the destination is actually reached. Hence, the main contribution of this paper is to present a trajectory planner with provable safety and task completion properties. Direct methods for trajectory optimization are traditionally based on a priori temporal discretization and collocation methods. In Paper D, the problem of adaptive node distribution is formulated as a constrained optimization problem, which is to be included in the underlying nonlinear mathematical programming problem. The benefits of utilizing the suggested method for  online  trajectory optimization are illustrated by a missile guidance example.In Paper E, the problem of active observer design for an important class of non-uniformly observable systems, namely mobile robotic systems, is considered. The set of feasible configurations and the set of output flow equivalent states are defined. It is shown that the inter-relation between these two sets may serve as the basis for design of active observers. The proposed observer design methodology is illustrated by considering a  unicycle robot model, equipped with a set of range-measuring sensors. Finally, in Paper F, a geometrically intrinsic observer for Euler-Lagrange systems is defined and analyzed. This observer is a generalization of the observer proposed by Aghannan and Rouchon. Their contractivity result is reproduced and complemented  by  a proof  that the region of contraction is infinitely thin. Moreover, assuming a priori bounds on the velocities, convergence of the observer is shown by means of Lyapunov's direct method in the case of configuration manifolds with constant curvature. / QC 20100622 / TAIS, AURES

<p>The main body of this thesis consists of four appended papers. The first two consider different aspects of the trajectory planning problem, while the last two deal with observer design for mobile robotic and Euler-Lagrange systems respectively.</p><p>The first paper addresses the problem of designing a real time, high performance trajectory planner for aerial vehicles. The main contribution is two-fold. Firstly, by augmenting a novel safety maneuver at the end of the planned trajectory, this paper extends previous results by having provable safety properties in a 3D setting. Secondly, assuming initial feasibility, the planning method is shown to have finite time task completion. Moreover, in the second part of the paper, the problem of simultaneous arrival of multiple aerial vehicles is considered. By using a time-scale separation principle, one is able to adopt standard Laplacian control to this consensus problem, which is neither unconstrained, nor first order.</p><p>Direct methods for trajectory optimization are traditionally based on<i> a</i> <i>priori </i>temporal discretization and collocation methods. In the second paper, the problem of adaptive node distribution is formulated as a constrained optimization problem, which is to be included in the underlying nonlinear mathematical programming problem. The benefits of utilizing the suggested method for online trajectory optimization are illustrated by a missile guidance example.</p><p>In the third paper, the problem of active observer design for an important class of non-uniformly observable systems, namely mobile robotics systems, is considered. The set of feasible configurations and the set of output flow equivalent states are defined. It is shown that the inter-relation between these two sets may serve as the basis for design of active observers. The proposed observer design methodology is illustrated by considering a unicycle robot model, equipped with a set of range-measuring sensors.</p><p>Finally, in the fourth paper, a geometrically intrinsic observer for Euler-Lagrange systems is defined and analyzed. This observer is a generalization of the observer recently proposed by Aghannan and Rouchon. Their contractivity result is reproduced and complemented by a proof that the region of contraction is infinitely thin. However, assuming <i>a</i> <i>priori </i>bounds on the velocities, convergence of the observer is shown by means of Lyapunov's direct method in the case of configuration manifolds with constant curvature.</p>

2002年元月，美國小布希總統宣稱北韓與伊拉克、伊朗，同屬「邪惡軸心」（Axis of Evil）國家，這些國家均係美國列入防止核武擴散之對象，於是北韓與美國關係旋墜落谷底，北韓之鬥爭策略是先昇溫，復加壓，然後迫使美國讓步；北韓復於2006年10月9日，正式對外宣布成功進行地下核武試驗，此舉無疑對東亞及國際安全均帶來衝擊。台灣基於同為亞太國家成員之一，應該理解北韓核武危機所牽動東北亞安全環境變化，以及美國、日本、中國及俄羅斯等國家多邊體系關係，倘北韓核武危機未能圓滿解決，擁核後之北韓除易成為東北亞潛伏威脅外，將引起日本加速武裝。北韓除製造核武問題外，北韓經濟困頓、民不聊生，朝鮮勞動黨為維繫獨裁政權統治，大肆販售飛彈等軍火牟取利益，甚至遭控訴涉及國際間多起販毒、製造假煙及偽造美鈔事件，而台灣位居東亞海空交通樞紐，台灣海峽為北韓船隻往來必經之路，因而有必要瞭解北韓政軍經現況，深入剖析北韓對於國際間衍生種種安全問題，訂定因應措施，以確保國家安全。 由於台灣外交情勢嚴峻，往往無法參與區域性國際組織，北韓乃伺機對台洽購精密儀器或刺探高科技產業技術，使得台灣容易成為北韓覬覦獲得國際管制性物品漏洞，本論文試圖探究並思索如何防止北韓向台灣採購可供軍事用途之精密儀器等用品，或可供生產提昇國防武器裝備之科技機器流向北韓，並配合國際反恐措施予以列管，這樣不僅符合國際利益，而且可以提昇台灣國際形象與國家地位；況且台灣亦有必要隨時瞭解國際上及美、歐等先進國家之最新出口管制措施，從而監督台灣廠商禁止將進口之高科技戰略性物品與生產之精密工具機，輾轉出口至管制地區（包括：伊朗、伊拉克、利比亞、北韓、中國、古巴、蘇丹等國），並配合國際防止擴散組織，共同防止大規模毀滅性武器擴散，形成全球安全之出口管制制度。 / In January 2002, President George W. Bush declared North Korea, Iraq, and Iran as an “axis of evil”. These countries are regarded as subject to the non-proliferation of nuclear weapons by the U.S. As a result, the relationship between North Korea and the U.S. has deteriorated. North Korea has attempted to gradually increase pressure to force the U.S. to concede; on October 9, 2006, North Korea officially announced the success of its secret nuclear weapon test, which undoubtedly made a tremendous impact on security in East Asia and the world. As a member of the Asia Pacific Region, Taiwan should understand how security in Northeast Asia changes due to the fact that North Korea is now a country with nuclear weapons. Taiwan should also be aware of the multilateral relations between the U.S., Japan, China, and Russia. Without a satisfactory solution to the threat of North Korean nuclear weapons, Japan may accelerate its military build-up in response to this lurking danger in Northeast Asia. Besides the nuclear weapon issue, North Korea has a poor economy and starving people. The Korean Workers’ Party has been accused of being involved in arms sale (such as missiles), international drug smuggling, counterfeit tobacco products, and counterfeit U.S. banknotes in order to maintain its dictatorship. As Taiwan’s geographic position is vital in the air and sea transport in East Asia, it is imperative for Taiwan to understand North Korea’s politics, armed forces, and economy. Taiwan must analyze and understand international security issues related to North Korea and map out corresponding actions so as to ensure national security. Due to its difficult diplomatic situation, Taiwan is unable to join many regional organizations. Therefore, North Korea takes this opportunity to purchase precision devices or pry into high technology from Taiwan. This makes Taiwan prone to become a legal loophole of which North Korea can take advantage to obtain international control items. This study investigates the ways for Taiwan to prevent North Korea from purchasing precision devices for military use or high-tech machinery that can improve defense weapons. In addition, the study also discusses how Taiwan can have better export control against North Korea by conforming to international anti-terror measures. To follow international principles is not only in line with global interests, but can also improve Taiwan’s international image and status. Therefore, Taiwan must keep itself updated of the latest export control measures implemented by the U.S., Europe, and other advanced countries. By doing so, Taiwan government can also prevent corporations in Taiwan from re-exporting strategic high-tech commodities and related production machinery to controlled territories, such as Iran, Iraq, Libya, North Korea, China, Cuba, and Sudan. With cooperation with international non-proliferation organizations, proliferation of WMDs can be stopped and a comprehensive export control network can be formed to maintain global security.

In the guidance literature, minimizing miss distance along with optimizing the energy usage had been an objective for several decades. In current day applications, additional terminal performance such as impact angle and impact time are of paramount importance. These terminal constraints increase warhead effectiveness and survivability of the interceptor. This thesis contributes to the design of guidance laws addressing terminal constraints such as impact angle, impact time, and both impact time as well as impact angle, in addition to interception of targets. In the first part of the thesis, the guidance laws which ensure the alignment of the interceptor at a desired impact angle within a finite time is proposed using different variants of sliding mode control(SMC).The impact angle is first redefined in terms of line-of-sight angle and then the impact angle problem is converted to a simpler problem of controlling line-of-sight angle and their rates. The sliding mode capturability and interpretation of the guidance laws are presented. In order to cater to very large heading angle errors, which give rise to negative closing speed initially, modifications to the guidance laws are also suggested. The modifications to the guidance laws for avoiding singularities, which may be encountered during implementation, due to the inherent nature of terminal SMC, are suggested. However, the guidance laws, which alleviates the possibility of such singularities completely, are also designed by using non singular terminal SMC. The two loop guidance and control, for a skid-to-turn cruciform interceptor in the pitch plane, is also proposed with an autopilot designed using the concept of dynamic SMC. The guidance laws addressing impact angle constraint for three dimensional scenarios are also presented. Unlike the usual approach of decoupling the three dimensional engagement in to two mutually orthogonal planar engagements, the guidance laws are derived using coupled engagement dynamics. These guidance laws are designed using conventional and non singular terminal SMC and provide asymptotic and finite time alignment of the intercept or to the desired impact angles, respectively. Next, the SMC based guidance laws which ensure the interception of targets at pre-specified impact times is proposed in this thesis. The guidance law is first designed for stationary targets and then extended to constant velocity targets using the notion of predicted interception point. A switching surface is designed using the concepts of collision course and time-to-go with non-linear engagement dynamics and its role in achieving the objectives is also discussed. In order to account for large heading angle errors and even for negative initial closing speeds, different methods of estimation of time-to-go, resulting in two different guidance laws, are used. Unlike the existing guidance laws, the proposed guidance laws achieve an impact time even less than its initially estimated value. The flexibility in selecting a desired impact time is also exploited using the maximum available acceleration information. A cooperative salvo attack strategy, based on the proposed impact time guidance law, with a desired impact time chosen in real time using a centralized coordination algorithm, is proposed for stationary targets. The coordination manager determines a common impact time based on time-to-goof the interceptors, by minimizing the total switching surface deviations which in turn reduces the control effort. The thesis also proposes a SMC based guidance strategy which addresses impact angle and impact time constraints simultaneously. This guidance scheme is based on switching between impact time and impact angle guidance laws based on certain conditions. Unlike existing impact time guidance laws, the proposed guidance strategy takes into account the curvature of the trajectory due to the impact angle requirement. The interceptor first corrects its course to nullify the impact time error and then aims to achieve interception with desired impact angle. In order to reduce the transitions between the two guidance laws, a novel hysteresis loop is introduced in the switching conditions. Initially stationary targets are considered, and later the same guidance scheme is extended to constant velocity targets using the notion of predicted interception point. Theclaimsofalltheguidancelawsarevalidatedwithextensivesimulationsandtheir performances are compared with existing guidance laws. Although all the guidance laws derived in the thesis are based on the assumption of constant speed interceptors, their performances are evaluated with a time-varying speed interceptor model, subjected to aerodynamic conditions, to validate their efficacy. The implementation of impact time guidance on time-varying speed interceptors is a formidable challenge in the guidance literature. Such implementations have also been presented in the thesis after introducing the notion of average speed and shown to yield satisfactory performance.

<div>Since as early as the 1920s, dinitrogen tetroxide (N2O4) has been regarded as a promising oxidizer in rocket propulsion systems. In more recent times, its predecessor, mixed oxides of nitrogen (MON), remains a top contender among oxidizers, due to its unique characteristics such as low freezing temperature and compatibility with common spacecraft materials. Today, these N2O4-based oxidizers are the preferred choice in many upper stages, launch escape systems, reaction control systems, liquid apogee engines, and in-space primary propulsion systems. N2O4-based oxidizers are a key factor in rocket propulsion, and thoroughly understanding their history, development, characteristics, synthesis, and composition analysis are crucial for space exploration today and into the future.<br><br></div><div>To fully understand and predict the physical properties of a MON sample, it is important to measure and quantify its chemical composition. The recommended method for MON composition analysis, as prescribed by the Department of Defense’s Defense Specification (MIL-SPEC) document on N2O4, involves the oxidation of NO and dinitrogen trioxide (N2O3) in the MON sample to determine their amounts. An equation unofficially called the “MIL-SPEC equation” is then used to determine the amount of NO needed to mix with N2O4 to synthesize that particular MON sample. However, no explanation is given as to how the equation was derived, or its significance.<br><br></div><div>This thesis aims to collect and organize key information on the synthesis, handling, and composition analysis of MON propellant. First, the history of development of N2O4-based oxidizers was researched, and current and future uses of N2O4 and MON propellants were identified. Then a method for synthesis and composition analysis was devised and tested. Water contamination was expected of skewing the results, so the process of water contamination was examined analytically. Then a detailed derivation of the MIL-SPEC equation was conducted, to fully understand its mechanics. An attempt was then made to reverse-engineer an unexplained numerical value in the equation, labeled by the author as the “solubility factor”. Several derivations were provided with varying degrees of complexity, producing alternative solubility factors of varying accuracies. Finally, experimental data was applied to these derived, hypothetical solubility factors and the MIL-SPEC solubility factor, with the intent of determining whether improvements could be made to the MON composition determination process.<br><br></div><div>The results suggest that the MIL-SPEC equation is sufficient for providing a relatively accurate measurement of the composition of a MON sample, while also being easy to implement, both in taking the necessary measurements and in conducting the numerical calculation. However, some minor adjustments to the equation could produce consistently more accurate composition measurements without adding any more difficulty or complication.</div>

<div>The orbits of interest for potential missions are stable or nearly stable to maintain long term presence for conducting scientific studies and to reduce the possibility of rapid departure. Near Rectilinear Halo Orbits (NRHOs) offer such stable or nearly stable orbits that are defined as part of the L1 and L2 halo orbit families in the circular restricted three-body problem. Within the Earth-Moon regime, the L1 and L2 NRHOs are proposed as long horizon trajectories for cislunar exploration missions, including NASA's upcoming Gateway mission. These stable or nearly stable orbits do not possess well-distinguished unstable and stable manifold structures. As a consequence, existing tools for stationkeeping and transfer trajectory design that exploit such underlying manifold structures are not reliable for orbits that are linearly stable. The current investigation focuses on leveraging stretching direction as an alternative for visualizing the flow of perturbations in the neighborhood of a reference trajectory. The information supplemented by the stretching directions are utilized to investigate the impact of maneuvers for two contrasting applications; the stationkeeping problem, where the goal is to maintain a spacecraft near a reference trajectory for a long period of time, and the transfer trajectory design application, where rapid departure and/or insertion is of concern.</div><div><br></div><div>Particularly, for the stationkeeping problem, a spacecraft incurs continuous deviations due to unmodeled forces and orbit determination errors in the complex multi-body dynamical regime. The flow dynamics in the region, using stretching directions, are utilized to identify appropriate maneuver and target locations to support a long lasting presence for the spacecraft near the desired path. The investigation reflects the impact of various factors on maneuver cost and boundedness. For orbits that are particularly sensitive to epoch time and possess distinct characteristics in the higher-fidelity ephemeris model compared to their CR3BP counterpart, an additional feedback control is applied for appropriate phasing. The effect of constraining maneuvers in a particular direction is also investigated for the 9:2 synodic resonant southern L2 NRHO, the current baseline for the Gateway mission. The stationkeeping strategy is applied to a range of L1 and L2 NRHOs, and validated in the higher-fidelity ephemeris model.</div><div><br></div><div>For missions with potential human presence, a rapid transfer between orbits of interest is a priority. The magnitude of the state variations along the maximum stretching direction is expected to grow rapidly and, therefore, offers information to depart from the orbit. Similarly, the maximum stretching in reverse time, enables arrival with a minimal maneuver magnitude. The impact of maneuvers in such sensitive directions is investigated. Further, enabling transfer design options to connect between two stable orbits. The transfer design strategy developed in this investigation is not restricted to a particular orbit but applicable to a broad range of stable and nearly stable orbits in the cislunar space, including the Distant Retrograde Orbit (DROs) and the Low Lunar Orbits (LLO) that are considered for potential missions. Examples for transfers linking a southern and a northern NRHO, a southern NRHO to a planar DRO, and a southern NRHO to a planar LLO are demonstrated.</div>