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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Optimal and suboptimal corrections for proportional navigation

Cottrell, Ronald Gelnn, 1942- January 1970 (has links)
No description available.
2

A study of observability-enhanced guidance systems / by George Estandy Hassoun.

Hassoun, George Estandy January 1995 (has links)
Erratum pasted on front fly leaf. / Bibliography: leaves 204-214. / xxi, 214 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis investigates a novel guidance law dubbed "observable proportional navigation". Two distinct forms of this guidance law are considered, based on the nature of the associated noise and state estimator. Closed-form solutions are given and necessary limits on the co-efficient of observability are determined. Both forms of the new law are applied to a two-dimensional missile-target bearing-only-measurement problem. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 1995
3

Kill vehicle effectiveness for boost phase interception of ballistic missiles

Bardanis, Florios 06 1900 (has links)
Approved for public release; distribution is unlimited / Boost phase interception of ballistic missiles is envisioned as the primary response of the layered defense architecture implemented in the ballistic missile defense system. A limited time frame in which to take action and the necessity to implement hit-to-kill technology in the kill vehicle counterbalances the many advantages of boost phase interception. Direct hit missile technology is constrained by the requirement to minimize miss distance to a negligible amount between the kill vehicle and optimum aimpoint on the target. This thesis examines kill vehicle effectiveness, which is tantamount to miss distance, as a function of both the kill vehicle maximum acceleration capability and the guidance system time constant necessary to destroy a target. The kill vehicle guidance system is modeled in MATLAB as a fifth-order binomial series with proportional navigation. The simulation examines the effect of an accelerating target attributed to powered flight and aimpoint displacement caused by a shift in tracking point from the target plume to the payload when resolution occurs. The kill vehicle minimum requirements as indi-cated by the simulation include a lateral acceleration capability of four times the target acceleration and a guidance system time constant that is less than one-tenth the estimated flight time. / Lieutenant, Canadian Navy
4

Optimering av slutfasstyrning / Optimization of terminal guidance

Persson, Mathias January 2002 (has links)
Modern missiles must meet higher and higher demands. They should be autonomous, have long range and still have a big effect on the target. To maximize effect on target some missiles not only minimize miss distance, but also try to hit with a certain angle; often perpendicular to the surface of the target. In this thesis a method to guide the missile in the terminal phase of its mission where both point of impact as angle of impact are specified. The method consist of two parts. First a reference trajectory with best possible impact conditions, considering the performance of the missile, is computed. The second part consist of a guidance law which guide the missile along the reference trajectory to the target. Two laws were tested, Biased Proportional Navigation (BPN) and Modified Biased Proportional Navigation (MBPN). The method was implemented in an existing detailed simulation system. A big number of simulations were done to optimize the algorithms, and to evaluate performance. Performance was then compared to an already existing method for terminal guidance. The new method was better in terms of angle of impact but worse considering point of impact. One big advantage with the new method is that after calculation of the reference trajectory but before the actual flight (to target) it is possible to predict, with a high level of certainty, if the missile is going to hit the target or not.
5

Optimering av slutfasstyrning / Optimization of terminal guidance

Persson, Mathias January 2002 (has links)
<p>Modern missiles must meet higher and higher demands. They should be autonomous, have long range and still have a big effect on the target. To maximize effect on target some missiles not only minimize miss distance, but also try to hit with a certain angle; often perpendicular to the surface of the target. </p><p>In this thesis a method to guide the missile in the terminal phase of its mission where both point of impact as angle of impact are specified. The method consist of two parts. First a reference trajectory with best possible impact conditions, considering the performance of the missile, is computed. The second part consist of a guidance law which guide the missile along the reference trajectory to the target. Two laws were tested, Biased Proportional Navigation (BPN) and Modified Biased Proportional Navigation (MBPN). </p><p>The method was implemented in an existing detailed simulation system. A big number of simulations were done to optimize the algorithms, and to evaluate performance. </p><p>Performance was then compared to an already existing method for terminal guidance. The new method was better in terms of angle of impact but worse considering point of impact. One big advantage with the new method is that after calculation of the reference trajectory but before the actual flight (to target) it is possible to predict, with a high level of certainty, if the missile is going to hit the target or not.</p>
6

A New Paradigm in Optimal Missile Guidance

Morgan, Robert W. January 2007 (has links)
This dissertation investigates advanced concepts in terminal missile guidance. The terminal phase of missile guidance usually lasts less than ten seconds and calls for very accurate maneuvering to ensure intercept. Technological advancements have produced increasingly sophisticated threats that greatly reduce the effectiveness of traditional approaches to missile guidance. Because of this, terminal missile guidance is, and will remain, an important and active area of research. The complexity of the problem and the desire for an optimal solution has resulted in researchers focusing on simplistic, usually linear, models. The fruit of these endeavors has resulted in some of the world's most advanced weapons systems. Even so, the resulting guidance schemes cannot possibly counter the evolving threats that will push the system outside the linear envelope for which they were designed. The research done in this dissertation greatly extends previous research in the area of optimal missile guidance. Herein it is shown that optimal missile guidance is fundamentally a pairing of an optimal guidance strategy and an optimal control strategy. The optimal guidance strategy is determined from a missile's information constraints, which are themselves largely determined from the missile's sensors. The optimal control strategy is determined by the missile's control constraints, and works to achieve a specified guidance strategy. This dichotomy of missile guidance is demonstrated by showing that missiles having different control constraints utilize the same guidance strategy so long as the information constraints are the same. This concept has hitherto been unrecognized because of the difficulty in developing an optimal control for the nonlinear set of equations that result from control constraints. Having overcome this difficulty by indirect means, evidence of the guidance strategy paradigm emerged. The guidance strategy paradigm is used to develop two advanced guidance laws. The new guidance laws are compared qualitatively and quantitatively with existing guidance laws.
7

A target/missile engagement scenario using classical proportional navigation

Lukenbill, Francis C. January 1990 (has links) (PDF)
Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 1990. / Thesis Advisor(s): Titus, Harold A. Second Reader: Powell, James R. "December 1990." Description based on title screen as viewed on April 1, 2010. DTIC Descriptor(s): Guided Missiles, Simulation, Forward Areas, Optimization, Transfer Functions, Guided Missile Warheads, Dynamics, Two Dimensional, Theses, Targets, Time, Three Dimensional, Solutions (General), Homing Devices, Maneuvers, Evasion, Simplification, Proportional Navigation, Automatic Pilots, Guided Missile Components, Miss Distance. DTIC Identifier(s): Proportional Navigation, Guided Missile Targets, Evasion, Flight Maneuvers, Intercept Trajectories, Guided Missile Trajectories, Antiaircraft Missiles, Aircraft Defense Systems, Miss Distance, Optimization, Adjoint Models, Survivability, Barrel Roll Maneuver, Split S Maneuver, Scenarios, Computer Programs, Theses. Author(s) subject terms: Proportional Navigation, Miss Distance, Adjoint. Includes bibliographical references (p. 111). Also available in print.
8

Tracking of Ground Mobile Targets by Quadrotor Unmanned Aerial Vehicles

Tan, Ruoyu 23 October 2013 (has links)
No description available.
9

Robust Estimation And Adaptive Guidance For Multiple Uavs' Cooperation

Allen, Randal 01 January 2009 (has links)
In this paper, an innovative cooperative navigation method is proposed for multiple Unmanned Air Vehicles (UAVs) based on online target position measurements. These noisy position measurement signals are used to estimate the target's velocity for non-maneuvering targets or the target's velocity and acceleration for maneuvering targets. The estimator's tracking capability is physically constrained due to the target's kinematic limitations and therefore is potentially improvable by designing a higher performance estimator. An H-infinity filter is implemented to increase the robustness of the estimation accuracy. The performance of the robust estimator is compared to a Kalman filter and the results illustrate more precise estimation of the target's motion in compensating for surrounding noises and disturbances. Furthermore, an adaptive guidance algorithm, based on the seeker's field-of-view and linear region, is used to deliver the pursuer to the maneuvering target. The initial guidance algorithm utilizes the velocity pursuit guidance law because of its insensitivity to target motion; while the terminal guidance algorithm leverages the acceleration estimates (from the H-infinity filter) to augment the proportional navigation guidance law for increased accuracy in engaging maneuvering targets. The main objective of this work is to develop a robust estimator/tracker and an adaptive guidance algorithm which are directly applicable UAVs.
10

Proportional navigation target tracking

Pittelkau, Mark Edward January 1983 (has links)
Motivated by the fact that anti-ship missiles present a serious threat to today's Navy, a tracking filter which will give superior tracking and trajectory extrapolation when tracking anti-ship missiles is desired. Because most anti-ship missiles use proportional navigation in their guidance systems, it is best to model their motion using the proportional navigation guidance law. An unbiased narrowband filter is required because the state estimate is used to extrapolate the trajectory over the long time of flight of the gun projectile used to intercept the anti-ship missile. Using the proportional navigation guidance law, a tracking filter is developed which meets the stated requirements. An advantage in using the proportional navigation model, which is not found in previous target models, is the end goal or destination constraint inherent in the proportional navigation guidance law: the anti-ship missile's goal is to strike ownership; the proportional navigation trajectory always passes through the origin. Because of model mismatch when tracking missiles using proportional navigation guidance, previous tracking filters, which use constant velocity, exponentially correlated acceleration, or constant acceleration models of target motion, must use a wide bandwidth or else develop significant bias errors. / M.S.

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