Download or read book Low thrust Trajectory Optimization Using Stochastic Optimization Methods written by John William Hartmann and published by . This book was released on 1999 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stochastic Optimization Methods written by Kurt Marti and published by Springer Science & Business Media. This book was released on 2005-12-05 with total page 317 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optimization problems arising in practice involve random parameters. For the computation of robust optimal solutions, i.e., optimal solutions being insensitive with respect to random parameter variations, deterministic substitute problems are needed. Based on the distribution of the random data, and using decision theoretical concepts, optimization problems under stochastic uncertainty are converted into deterministic substitute problems. Due to the occurring probabilities and expectations, approximative solution techniques must be applied. Deterministic and stochastic approximation methods and their analytical properties are provided: Taylor expansion, regression and response surface methods, probability inequalities, First Order Reliability Methods, convex approximation/deterministic descent directions/efficient points, stochastic approximation methods, differentiation of probability and mean value functions. Convergence results of the resulting iterative solution procedures are given.
Download or read book Hybrid Methods for Interplanetary Low thrust Trajectory Optimization written by Krisada Aroonwilairut and published by . This book was released on 2002 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Design of Trajectory Optimization Approach for Space Maneuver Vehicle Skip Entry Problems written by Runqi Chai and published by Springer. This book was released on 2019-07-30 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores the design of optimal trajectories for space maneuver vehicles (SMVs) using optimal control-based techniques. It begins with a comprehensive introduction to and overview of three main approaches to trajectory optimization, and subsequently focuses on the design of a novel hybrid optimization strategy that combines an initial guess generator with an improved gradient-based inner optimizer. Further, it highlights the development of multi-objective spacecraft trajectory optimization problems, with a particular focus on multi-objective transcription methods and multi-objective evolutionary algorithms. In its final sections, the book studies spacecraft flight scenarios with noise-perturbed dynamics and probabilistic constraints, and designs and validates new chance-constrained optimal control frameworks. The comprehensive and systematic treatment of practical issues in spacecraft trajectory optimization is one of the book’s major features, making it particularly suited for readers who are seeking practical solutions in spacecraft trajectory optimization. It offers a valuable asset for researchers, engineers, and graduate students in GNC systems, engineering optimization, applied optimal control theory, etc.
Download or read book Stochastic Optimization written by Johannes Schneider and published by Springer Science & Business Media. This book was released on 2007-08-06 with total page 551 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses stochastic optimization procedures in a broad manner. The first part offers an overview of relevant optimization philosophies; the second deals with benchmark problems in depth, by applying a selection of optimization procedures. Written primarily with scientists and students from the physical and engineering sciences in mind, this book addresses a larger community of all who wish to learn about stochastic optimization techniques and how to use them.
Download or read book Optimization of Low thrust Spacecraft Trajectories by Direct Shooting Methods microform written by Christopher Rampersad and published by Library and Archives Canada = Bibliothèque et Archives Canada. This book was released on 2004 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: The direct approach for trajectory optimization was found to be very robust. For most problems, solutions were obtained even with poor initial guesses for the controls. The direct approach was also found to be only slightly less accurate than the indirect methods found in the literature (within 0.7%). The present study investigates minimum-time and minimum-fuel low-thrust trajectory problems via a single shooting direct method. Various Earth-based and interplanetary case studies have been examined and have yielded good agreement with similar cases in the literature. Furthermore, new near-optimal trajectory problems have been successfully solved. A multiple-orbit thrust parameterization strategy was also developed to solve near-optimal very-low-thrust Earth-based transfers. Lastly, this thesis examines the use of the high-accuracy complex-step derivative approximation method for solving low-thrust transfer problems. For certain very nonlinear transfer problems, the complex-step derivative approximation was found to increase the robustness of the single shooting direct method.
Download or read book Advanced Trajectory Optimization Guidance and Control Strategies for Aerospace Vehicles written by Runqi Chai and published by Springer Nature. This book was released on 2023-10-29 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the design and application of advanced trajectory optimization and guidance and control (G&C) techniques for aerospace vehicles. Part I of the book focuses on the introduction of constrained aerospace vehicle trajectory optimization problems, with particular emphasis on the design of high-fidelity trajectory optimization methods, heuristic optimization-based strategies, and fast convexification-based algorithms. In Part II, various optimization theory/artificial intelligence (AI)-based methods are constructed and presented, including dynamic programming-based methods, model predictive control-based methods, and deep neural network-based algorithms. Key aspects of the application of these approaches, such as their main advantages and inherent challenges, are detailed and discussed. Some practical implementation considerations are then summarized, together with a number of future research topics. The comprehensive and systematic treatment of practical issues in aerospace trajectory optimization and guidance and control problems is one of the main features of the book, which is particularly suitable for readers interested in learning practical solutions in aerospace trajectory optimization and guidance and control. The book is useful to researchers, engineers, and graduate students in the fields of G&C systems, engineering optimization, applied optimal control theory, etc.
Download or read book Advances in Low thrust Trajectory Optimization and Flight Mechanics written by Yang Gao and published by . This book was released on 2003 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dissertation presents advances in trajectory optimization and flight mechanics of low-thrust spacecraft. With the aid of the extended multiple-shooting techniques with state and costate nodes, the hybrid method and the direct-shooting method are systematically described and used to solve a variety of optimal orbit transfer problems. The optimization methods are demonstrated by presenting solutions for optimal Earth-orbit and interplanetary trajectory examples, and complex interplanetary missions using solar electric propulsion (such as Eros sample return and Pluto-flyby missions). Alternative formulations of equations of motion are discussed, which include inertial frame transformation in terms of three Euler angles and a modified set of equinoctial elements using non-dimensional angular momentum. Finally, a low-thrust Earth-capture guidance scheme is developed and presented, which makes novel use of Perkins' low-thrust universal solution and doesn't require a stored reference trajectory. The simplicity and performance of this new guidance design makes it a viable candidate for onboard implementation.
Download or read book Stochastic Optimization written by Ioannis Dritsas and published by BoD – Books on Demand. This book was released on 2011-02-28 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stochastic Optimization Algorithms have become essential tools in solving a wide range of difficult and critical optimization problems. Such methods are able to find the optimum solution of a problem with uncertain elements or to algorithmically incorporate uncertainty to solve a deterministic problem. They even succeed in fighting uncertainty with uncertainty. This book discusses theoretical aspects of many such algorithms and covers their application in various scientific fields.
Download or read book Low thrust Trajectory Optimization Using a Discretized Impulsive Thrust Model written by Evgeniy Sklyanskiy and published by . This book was released on 2004 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spacecraft Trajectory Optimization written by Bruce A. Conway and published by Cambridge University Press. This book was released on 2010-08-23 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a long-overdue volume dedicated to space trajectory optimization. Interest in the subject has grown, as space missions of increasing levels of sophistication, complexity, and scientific return - hardly imaginable in the 1960s - have been designed and flown. Although the basic tools of optimization theory remain an accepted canon, there has been a revolution in the manner in which they are applied and in the development of numerical optimization. This volume purposely includes a variety of both analytical and numerical approaches to trajectory optimization. The choice of authors has been guided by the editor's intention to assemble the most expert and active researchers in the various specialities presented. The authors were given considerable freedom to choose their subjects, and although this may yield a somewhat eclectic volume, it also yields chapters written with palpable enthusiasm and relevance to contemporary problems.
Download or read book Low thrust Trajectory Optimization Using Differential Inclusion Concepts written by Daniel Pierre Thunnissen and published by . This book was released on 1996 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Low thrust Trajectory Optimization and Interplanetary Mission Analysis Using Evolutionary Neurocontrol written by Bernd Dachwald and published by . This book was released on 2004 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Reinforcement Learning Approach to Spacecraft Trajectory Optimization written by Daniel S. Kolosa and published by . This book was released on 2019 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation explores a novel method of solving low-thrust spacecraft targeting problems using reinforcement learning. A reinforcement learning algorithm based on Deep Deterministic Policy Gradients was developed to solve low-thrust trajectory optimization problems. The algorithm consists of two neural networks, an actor network and a critic network. The actor approximates a thrust magnitude given the current spacecraft state expressed as a set of orbital elements. The critic network evaluates the action taken by the actor based on the state and action taken. Three different types of trajectory problems were solved, a generalized orbit change maneuver, a semimajor axis change maneuver, and an inclination change maneuver. When training the algorithm in a simulated space environment, it was able to solve both the generalized orbit change and semimajor axis change maneuvers with no prior knowledge of the environment’s dynamics. The robustness of the algorithm was tested on an inclination change maneuver with a randomized set of initial states. After training, the algorithm was able to successfully generalize and solve new inclination changes that it has not seen before. This method has potential future applications in developing more complex low-thrust maneuvers or real-time autonomous spaceflight control.
Download or read book Advances in Cooperative Control and Optimization written by Michael Hirsch and published by Springer. This book was released on 2007-10-24 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: Across the globe, the past several years have seen a tremendous increase in the role of cooperative autonomous systems. The field of cooperative control and optimization has established itself as a part of many different scientific disciplines. The contents of this hugely important volume, which adds much to the debate on the subject, are culled from papers presented at the Seventh Annual International Conference on Cooperative Control and Optimization, held in Gainesville, Florida, in January 2007.
Download or read book Three dimensional Low thrust Trajectory Optimization with Applications written by James K. Whiting and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamic Stochastic Optimization written by Kurt Marti and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: Uncertainties and changes are pervasive characteristics of modern systems involving interactions between humans, economics, nature and technology. These systems are often too complex to allow for precise evaluations and, as a result, the lack of proper management (control) may create significant risks. In order to develop robust strategies we need approaches which explic itly deal with uncertainties, risks and changing conditions. One rather general approach is to characterize (explicitly or implicitly) uncertainties by objec tive or subjective probabilities (measures of confidence or belief). This leads us to stochastic optimization problems which can rarely be solved by using the standard deterministic optimization and optimal control methods. In the stochastic optimization the accent is on problems with a large number of deci sion and random variables, and consequently the focus ofattention is directed to efficient solution procedures rather than to (analytical) closed-form solu tions. Objective and constraint functions of dynamic stochastic optimization problems have the form of multidimensional integrals of rather involved in that may have a nonsmooth and even discontinuous character - the tegrands typical situation for "hit-or-miss" type of decision making problems involving irreversibility ofdecisions or/and abrupt changes ofthe system. In general, the exact evaluation of such functions (as is assumed in the standard optimization and control theory) is practically impossible. Also, the problem does not often possess the separability properties that allow to derive the standard in control theory recursive (Bellman) equations.
