The survival of our nation, during a nuclear exchange, depends upon an effective national defense structure. The prime weapon system in this defense structure is the ballistic missile. Although many factors enter into an evaluation of the effectiveness of a ballistic missile, one of the most important measure is accuracy. Without an accurate weapon system we have no weapon system. The Department of Defense has places emphasis on using a method of accuracy evaluation called "Probably Circular Error (CEP)." Probably Circular Error is defined as "The radius of a circle, centered at the intended target, within which 50% of the missiles would be expected to impact" or "The probability is 0.50 that an individual missile will impact within a circle whose radius is equal to the CEP." The statistical techniques and assumptions used in generation a CEP value will be investigated.

Målet med detta examensarbete var att undersöka och ta fram ett konstruktionsförslag av en bärgningsmodul anpassad för Saabs robotsystem, RBS15, vilket skulle möjliggöra återanvändning av komponenter och underlätta utvärderingar av flygkroppen. Liknande system används av andra företag inom försvarsindustrin för att kunna utvärdera sina produkter. I examensarbetet har olika aspekter av bärgningssystemet undersökts, inklusive analys av fallskärmsinitiering, dimensionering av fallskärmar och infästningspunkter, samt packningsstudier av fallskärmsystemet. Litteraturstudier, intervjuer och simuleringar har använts som lösningsmetoder för att analysera och modellera systemet och dess komponenter. Beräknade krafter och flygbana visade att de befintliga spanten och infästningspunkterna på roboten klarade belastningen från fallskärmssystemet. Slutsatsen är att en bärgningsmodul till RBS15 har stor potential. Med detta system skulle roboten kunna återanvändas och utvärderas effektivt, vilket kan leda till ekonomiska fördelar och underlätta framtida utveckling av systemet. / The objective of this thesis was to investigate and develop a design proposal for a recovery module for Saab's missile system, RBS15, which would enable component reusability and facilitate evaluations of the missile. Similar systems are utilized by other companies in the defense industry to assess their products. The thesis project has explored various aspects of the recovery system, including parachute initiation analysis, dimensioning of parachutes with their affiliated attachment points, and packing studies of the parachute system. Literature reviews, interviews, and simulations have been employed as methods to analyze and model the system and its components. Calculated forces and flight trajectory demonstrate that the existing frames and attachment points on the missile can withstand the load from the parachute system. The conclusion is that a recovery module for RBS15 holds significant potential. With this system, the missile could be effectively reused and evaluated, which can lead to economic benefits and facilitating future system development.

Nonlinear stabilization and control autopilots are capable of sustaining nominal performance throughout the entire fight envelope an interceptor missile may encounter during hostile engagements and require no gain scheduling to maintain autopilot stability. Due to non minimum phase conditions characteristic of tail controlled missile airframes, a separation of time scales within the dynamic equations of motion between rotational and translational differential equations was enforced to overcome unstable effects of non minimum phase. Dynamic inversion techniques are then applied to derive linearizing equations which, when injected forward into the plant result in a fully controllable linear system. Objectives of the two time scale control architecture are to stabilize vehicle rotational rates while at the same time controlling acceleration within the lateral plane of the vehicle under rapidly increasing dynamic pressure. Full 6 degree of freedom dynamic terms including all coriolis accelerations due to translational and rotational dynamic coupling have been taken into account in the inversion process. The result is a very stable, nonlinear autopilot with fixed control gains fully capable of stable nonlinear missile control. Several actuator systems were also designed to explore the destabilizing effects second order nonlinear actuator characteristics can have on nonlinear autopilot designs.

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<p>Activity planning for space mission operations has traditionally been a human-in-the-loop effort, conducted by ground operators. Over the past two decades, advances have been made toward automating the mission planning process, in an effort to improve the efficiency of the mission operations system, while increasing the mission return. In keeping with NASA’s goals, some aspects of onboard mission planning are increasingly used for complex missions, particularly for planetary surface missions that are subject to long communication delays.</p> <p>This dissertation research develops an automated mission planning framework and applies it to two spacecraft scenario case studies: a science orbiter and a science rover mission. Mission plans are optimized on the basis of science return, accommodating spacecraft movement</p> <p>to sites of scientific interest according to ground-team preferences, while staying within rover engineering and traverse-related constraints. Automated mission planners offer the capability to schedule engineering and science activities onboard, without ground-in-the-loop interaction. Resource modeling and path planning can be done onboard, reducing the need for modeling and verification by ground operators. Further, automated mission planners</p> <p>may incorporate an optimization executive that maximizes the mission return within the available resource constraints. The proposed planners may be utilized onboard autonomous spacecraft and rovers with limited human support. Also, they may be run on the ground by</p> <p>mission planning teams to provide additional insight during the planning process. Utilizing a variety of optimization approaches, the developed automated mission planners establish the planned sequence of activities, including and engineering activities, while adhering to constraints imposed by orbital geometry or planetary pathing requirements and resource availability. The focus of the work is on remote, robotic missions in which human-in-the loop decision input is delayed or at times unavailable. Two major classes of robotic missions are examined: Orbital science missions in which primary science activities are performed periodically at a specified rate, and a planetary rover mission in which a larger variety of science activities are interspersed with unique terrain navigation activities. The automated mission planning framework is designed to be adapted based upon the application. Optimization methods suitable for different mission planning problems are presented, comparing methods on the basis of computation speed, resources required and solution value.</p> <p>The Aerospace Systems Engineering definitions for “robustness” and “flexibility” are given quantifiable, mathematical definitions and are incorporated into the framework as quality metrics to provide criteria with which to evaluate and compare the produced activity plans.</p> <p>The metrics “reliability” and “latent performance index” provide additional criteria for plan evaluation. A variety of automated mission planning algorithmic approaches are developed and described functionally and mathematically. Planning tools capable of plan verification, Monte Carlo simulation-based verification and plan variation analysis are developed and described in detail. Two detailed, step by step case studies are developed, applying and</p> <p>running all the mission planning and analysis tools to provide planning solutions and analysis of generated plans for the science orbiter and science rover scenarios. The application of the developed planning solutions to the presented missions, including the determination</p> <p>of the quality metrics, are seen as the primary contributions to the advancement of the</p> <p>state of the art in automated mission planning. The Automated Mission Planning and plan analysis techniques and practices are summarized into a User’s Guide to Automated Mission Planning. The guide aids the user in developing their own automated mission planning framework and applying it to their unique mission planning problems. Numerous avenues for future work are proposed to extend this research into other, useful areas. Two areas of road mapping—tasks that must be done to enable a future vision for improved automated planning—are discussed.</p>

<p dir="ltr">At the cusp of scientific discovery and innovation, mankind's next greatest challenge lies in developing capabilities to enable human presence in deep space. This entails setting up space infrastructure, travel pathways, managing spacecraft traffic, and building up deep space operation logistics. Spacecrafts that are a part of the infrastructure must be able to perform myriad of operations and transfers such as rendezvous and docking, station-keeping, loitering, collision avoidance etc. In support of this endeavour, an investigation is done to analyze and recreate the solution space for fuel-optimal trajectories and control histories required for onboard trajectory design of inexpensive spacecraft transfers and operations. This study investigates close range rendezvous (CRR), nearby orbital transfer, collision avoidance, and long range transfer maneuvers for spacecrafts whose highly complex and nonlinear behavior is modelled using the circular restricted three-body problem (CR3BP) dynamics and to which a finite-burn maneuver is augmented to model low-propulsion maneuvers. In order to study the nonlinear solution space for such maneuvers, this investigation contributes new formulations of nonlinear programming (NLP) optimal control problems solved to minimize fuel consumption, and validated by traditional methods already in use. This investigation proposes a Feature Learning based Optimal Control Method (L-OCM) to learn the solution space and recreate results in real-time. The NLP problem is solved off-line for a range of initial conditions. The set of solutions is used to generate datasets with initial conditions as inputs and the identified features of the optimal control solution as outputs. These features are inherent to reconstructing the optimal control histories of the solution and are selected keeping onboard computational capabilities in mind. Deep Neural Networks (DNNs) are trained to map the complex, nonlinear relationship between the inputs and outputs, and then implemented to find on-line solutions to any initial condition. The L-OCM method provides fuel-optimal, real-time solutions that can be implemented by a spacecraft performing operations in cislunar space.</p>

Due to increasingly difficult threats, current air defense missile systems are pushed to the limits of their performance capabilities. In order to defend against these more stressing threats, interceptor missiles require greater maneuverability, faster response time, and increased robustness to more severe environmental conditions. One of the most critical missile system elements is the flight control system, since its time constant is typically half of the total missile system time constant. Conventional autopilot design techniques have worked well in the past, but in order to satisfy future and more stringent design specifications, new design methods are necessary. Robust control techniques (in particular, H-Infinity Control and Mu-Synthesis) and their application to the design of missile autopilots are addressed in this thesis. In addition, conventional autopilot designs are performed as comparative benchmarks. This paper reviews the missile autopilot design problem and presents descriptions of the classical and H-Infinity/Mu design methods. Missile autopilot designs considering both rigid-body dynamics and elastic-body dynamics are presented. Comparisons of the design approaches and results are also discussed. The results show that the application of robust control techniques to the design of missile autopilots can improve the performance and stability robustness characteristics of the flight control system. / Master of Science

This research project assesses the continued utility of Allison's three policy-making models in analyzing contemporary foreign policy problems. It also explores the effect of cultural considerations on Allison's concepts by delving into the unique themes of Japanese politics. The climate in which this policy decision is made is framed through a discussion of the strategic environment and Japanese defense policy following the Cold War and 9/11. The rational actor, organizational process, and bureaucratic politics models are applied to Japan's 2003 decision to field a missile defense system through a qualitative analysis of English-language secondary hard-copy and online sources. Some Japanese government materials are reviewed as well; the Japanese language, however, presented challenges to research. Despite the expectation that the rational actor model best describes the Japanese approach to missile defense, this project shows the true value of Allison's theories lies in their capacity to expose issues relevant to policy problems from varying perspectives. Japan's missile defense policy likely resulted from a combination of the three models, each influenced in varying degrees by the cultural aspects of Japanese politics. / Master of Arts

Beginning in the 1990s, the United States and Japan began redefining their bilateral security alliance. This redefinition also prompted Japan to change its security policies. To what extent and in what ways have changes in the U.S.-Japan security alliance contributed to these changes? I argue that these changes are the result of negotiations of the Japan-U.S. Joint Declaration on Security Alliance for the 21st Century, signed on April 17, 1996, and the occurrence of an exogenous event. I also argue that the negotiated changes only progress to a certain point, at which time an exogenous event acts as a catalyst to continue change. I examine two cases of policy change associated with exogenous events (the U.S.-led invasion of Afghanistan and the 2003 North Korea Missile Crisis). Finally, I summarize my results that Japan was able to change its security policies through negotiations and through a series of systematic steps that follow a consistent trajectory of change; but exogenous events have continued the change that started as a result of the negotiations and the systematic steps. / Master of Arts

Decision-making during crises is an important task that many elected officials face during their time in office. This thesis seeks to identify principles that make up a sound policy decision-making process and may lead to more positive outcomes. The analysis here is a comparative case study of three national security crises that faced the John F. Kennedy administration: the Bay of Pigs, the Cuban Missile Crisis, and the Vietnam conflict. Each case is examined for the presence of indicators of groupthink. I hypothesize that the relative absence of groupthink is related to a positive outcome. That hypothesis is examined by reviewing each case; the cases that contained higher levels of the indicators of groupthink tended to have a poorer quality process than those with less evidence of groupthink. / Master of Arts