Impact time control based on time-to-go prediction for sea-skimming antiship missiles

This paper proposes a novel approach for guidance law design to satisfy the impact-time constraints for a certain class of homing missiles. The proposed guidance law provides proper lateral acceleration commands that make the impact time error converge to zero by the time of impact. This scheme can be applied to any existing guidance law for which a formula of predicted time to go is available. Convergence of time-to-go errors is supported by Lyapunov stability. The optimal guidance law and the impact angle control guidance law are extended by the proposed method for impact-time-control guidance and impact-time-and-angle-control guidance, respectively. The performance of the extended guidance laws is demonstrated by numerical simulation

The Third Battle

Since the beginning of the twentieth century, submarines have been the weapon of choice for weaker naval powers that wish to contest a dominant power\u27s control of the seas or its ability to project power ashore from the sea. This is because submarines have been and are likely to remain the weapon system with the highest leverage in a battle for control of the ocean surface. Hence, antisubmarine warfare (ASW) will always re-main the most important element of the U.S. Navy\u27s core mission-sea control.https://digital-commons.usnwc.edu/usnwc-newport-papers/1017/thumbnail.jp

Generalized formulation of linear nonquadratic weighted optimal error shaping guidance laws

This study presents a novel extension to the theory of optimal guidance laws represented by the nontraditional class of performance indices: nonquadratic-type signal Lp" role="presentation">Lp norm for the input weighted by an arbitrary positive function. Various missile guidance problems are generally formulated into a scalar terminal control problem based on the understanding of the predictor–corrector nature. Then, a new approach to derive the optimal feedback law, minimizing the nonquadratic performance index, is proposed by using the Hölderian inequality. The proposed extension allows a more general family of formulations for the design of closed-form feedback solutions to various guidance problems to be treated in a unified framework. The equivalence between the proposed approach and other design methodologies is investigated. In general, the type of input norm mainly determines the variability of input during the engagement while trading off against the rate of error convergence. The analytic solution derived in this study is verified by comparison with the solution from numerical optimization, and the effect of the exponent p" role="presentation">p in the performance index on the trajectory and command is demonstrated by numerical simulations

Energy-optimal waypoint-following guidance considering autopilot dynamics

This paper addresses the problem of energy-optimal waypoint-following guidance for an Unmanned Aerial Vehicle with the consideration of a general autopilot dynamics model. The proposed guidance law is derived as a solution of a linear quadratic optimal control problem in conjunction with a linearized kinematics model. The algorithm developed integrates path planning and following into a single step and is able to be applied to a general waypoint-following mission. Theoretical analysis reveals that previously suggested optimal point-to-point guidance laws are special cases of the proposed approach. Nonlinear numerical simulations clearly demonstrate the effectiveness of the proposed formulations

Thither the Russian Navy? Putin’s Navalization in a Historical Context

The Syrian operation of 2012 was the first successful employment by Russia of expeditionary warfare, narrowly defined as naval support to Russian (or Soviet) ground forces in a war away from their periphery (i.e., in a country that does not border them), from the sea. This was brought about in part by the development of two types of cruise missiles: advanced anti-ship missiles (which protects their expeditionary force from NATO naval units, enabling local sea control) and new land attack cruise missiles (similar in design and capability to the U.S. Tomahawk). In the past geographical, technological and political constraints have kept Russia from employing its navy in this manner. To prove this, Russia’s unique geographic situation must be understood, along with the development of naval warfare (in particular the concept of sea control). A review of Russian naval history will show that, though they aspired to such a capability, neither Imperial Russia nor the Soviet Union were able to accomplish this. In the modern age (defined as the turn of the 20th Century), two cases can be identified that involved a Russian/Soviet attempt at such expeditionary operations --- the Russo-Japanese War and the Spanish Civil War. In the former, though armed with what was considered a “great power” navy, geography and politics assured Russian naval defeat (leading to their defeat on land). In the latter, the lack of a great power fleet ensured that they were once again unable to support their ground forces, leading to withdrawal (and failure to achieve their objectives in Spain). In Syria, Russia was able to successfully support expeditionary ground forces, using amphibious transport protected by a balanced fleet of escorts with advanced-technology missiles, in addition to providing for the direct support of ground forces through employment of land attack cruise missiles. Both the case studies and late-Cold War doctrinal writings show that this has always been on the minds of the Russians, but the confluence of geographic realities, doctrine, and economic or technological shortcomings assured their inability to realize these objectives. As a result of this new capability, the modern Russian navy will continue to enjoy a more significant place in Russian military strategy, even following the Syrian conflict

Analytic approach to impact time guidance with look angle constraint using exact time-to-go solution

This paper proposes an analytic approach for impact time control guidance laws against stationary targets using biased proportional navigation. The proposed guidance scheme realizes the impact time control in two different ways: the first approach directly uses the exact time-to-go error to satisfy both the impact time control and the field-of-view constraint, while the second approach adopts a look angle tracking law to indirectly control the impact time, with the reference profile of the look angle generated using the exact time-to-go solution. The stability properties of the proposed guidance laws are discussed, and numerical simulations are carried out to evaluate their performance in terms of accuracy and efficiency