Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Optimal Trajectory Reconfiguration And Retargeting For A Reusable Launch Vehicle
Download Optimal Trajectory Reconfiguration And Retargeting For A Reusable Launch Vehicle full books in PDF, epub, and Kindle. Read online Optimal Trajectory Reconfiguration And Retargeting For A Reusable Launch Vehicle ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Optimal Trajectory Reconfiguration and Retargeting for a Reusable Launch Vehicle by :
Download or read book Optimal Trajectory Reconfiguration and Retargeting for a Reusable Launch Vehicle written by and published by . This book was released on 2005 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Autonomous reusable launch vehicles (RLV) are being pursued as low-cost alternatives to expendable launch vehicles and the Shuttle. The employment of autonomous reusable launch vehicles requires additional guidance and control robustness to fulfill the role of an adaptive human pilot, in the event of failures or unanticipated conditions. The guidance and control of these vehicles mandate new guidance strategies that are able to identify and adapt to vehicle failures during the flight and still return to earth safely. This work utilizes an online trim algorithm that provides the outer loop with the feasible range of Mach number and angle of attack, for which the vehicle can be rotationally trimmed. The algorithm allows one to include 6-degree-of-freedom (DOF) trim effects and constraints in a reduced order dynamical model which is used in the solution of an optimal control problem. A direct pseudospectral method is used to solve a two-point-boundary-value problem which determines the optimal entry trajectory subject to appropriate constraints such as normal load, dynamic pressure limits, heat load limits, and state dependent constraints.
Book Synopsis Optimal Trajectory Reconfiguration and Retargeting for the X-33 Reusable Launch Vehicle by : Patrick J. Shaffer
Download or read book Optimal Trajectory Reconfiguration and Retargeting for the X-33 Reusable Launch Vehicle written by Patrick J. Shaffer and published by . This book was released on 2004-09-01 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis considers the problem of generating optimal entry trajectories for a reusable launch vehicle following a control surface failure. The thesis builds upon the work of Dr. David Doman, Dr. Michael Oppenheimer and Dr. Michael Bolender of the Air Vehicles Directorate, Air Force Research Lab Dayton Ohio. The primary focus of this work is to demonstrate the feasibility of inner loop reconfiguration and outer loop trajectory retargeting and replanning for the X-33 reusable launch vehicle (RLV) following the imposition of a control surface failure. The trajectory generation model employs path constraints generated by an AFRL trim deficiency algorithm coupled with an inner loop control allocator and aerodynamic database that captures the full 6-DOF vehicle aerodynamic effects while utilizing an outer loop 3-DOF model. The resulting optimal trajectory does not violate the trim deficiency constraints and provides additional margins for trajectories flown during failure conditions. The footprints generated by the thesis show that contemporary footprint analysis for vehicles experiencing control surface failures are overly optimistic when compared to those footprints that consider vehicle aerodynamic stability and realistic landable attitudes at the threshold of the landing runway. The results of the thesis also show the performance reductions resulting from decoupling the inner and outer loop and that trajectories can be generated to the landing runway without using a region of terminal area energy management.
Book Synopsis Fault Tolerant Optimal Trajectory Generation for Reusable Launch Vehicles by : Patrick J. Shaffer
Download or read book Fault Tolerant Optimal Trajectory Generation for Reusable Launch Vehicles written by Patrick J. Shaffer and published by . This book was released on 2006 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reconfigurable inner-loop control laws improve the fault tolerance of a vehicle to control effector failures; however, in order to preserve stability, the unfailed effectors may be deployed to off-nominal positions to compensate for undesirable perturbations caused by the failed effectors. The effectors acting under the influence of a reconfigurable control law can produce significant perturbations to the nominal forces produced by the wing and body and can also affect the range of flight conditions over which the vehicle can be controlled. Three degree-of-freedom (3 DOF) dynamical models used in trajectory optimization for aerospace vehicles typically include wing-body aerodynamic force effects but ignore the aerodynamic forces produced by the control surfaces. In this work, a method for including these trim effects as well as control induced trajectory constraints in a 3 DOF model is presented.
Book Synopsis Optimal Guidance Command Generation and Tracking for Reusable Launch Vehicle Reentry (Preprint). by :
Download or read book Optimal Guidance Command Generation and Tracking for Reusable Launch Vehicle Reentry (Preprint). written by and published by . This book was released on 2006 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this work is to develop a robust guidance and control architecture for autonomous reusable launch vehicles that incorporates elements of recent advances in the areas of optimal trajectory generation and reconfigurable control. This work integrates three separately developed methods to form a coherent architecture with the potential to manage control effector failures, vehicle structural/aerodynamic degradation, uncertainty, and external disturbances. Outer-loop guidance commands in the form of body-frame angular rates (roll, pitch, and yaw) are generated from an optimal reference trajectory that is computed off-line with a direct pseudospectral method and then tracked by a reconfigurable inner-loop control law. The appropriate open-loop state histories from the pseudo-four-degree-of-freedom reference trajectory are converted using a modified backstepping approach that complements the inner-loop control law in a six-degree-of-freedom simulation. The inner-loop control law is capable of reacting and compensating for off-nominal conditions by employing nonlinear reconfigurable control allocation, dynamic inversion, and model-following/anti-windup prefilters. The results show that the inner loop control can adequately track the desired optimal guidance commands; thus, confirming that applicability of this control architecture for future development involving on-line, optimal trajectory generation and high-fidelity guidance and control for reentry vehicles.
Book Synopsis A Reconfigurable Guidance Approach for Reusable Launch Vehicles by :
Download or read book A Reconfigurable Guidance Approach for Reusable Launch Vehicles written by and published by . This book was released on 2001 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: A guidance system with reconfiguration capabilities has been developed for reusable launch vehicles (RLVs). The focus of the development is on reconfiguration after a catastrophic effector failure during final approach - a failure that would otherwise cause loss of the vehicle. We assume here that the vehicle employs a reconfigurable inner-loop control system that recovers some maneuvering capabilities and maintains attitude stability. However, for RLVs, it is often the case that nominal performance cannot be fully recovered, and the outer-loop guidance system must account for the degraded response characteristics. Two approaches are presented. The first approach augments the existing production guidance system with adaptation capabilities. A case study shows that stability is maintained following a primary pitch effector failure. However, it is shown that the trajectory commands to the guidance loops must also be re-targeted in order to achieve a safe landing. The second approach employs an on-line optimal trajectory re-targeting algorithm. A database of neighboring optimal trajectories is encoded in an efficient manner and interrogated on line at regular intervals. Given the current states and certain vehicle parameters, this procedure generates optimal guidance commands and integrates the optimal trajectory to the next update point. A proof-of-concept study of this approach was performed. Following a primary speed control failure, the study shows that this approach achieves acceptable landing conditions.
Book Synopsis Optimal Trajectory Designs and Systems Engineering Analyses of Reusable Launch Vehicles by : Hung-i Bruce Tsai
Download or read book Optimal Trajectory Designs and Systems Engineering Analyses of Reusable Launch Vehicles written by Hung-i Bruce Tsai and published by . This book was released on 2003 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt: Realizing a reusable launch vehicle (RLV) that is low cost with highly effective launch capability has become the "Holy Grail" within the aerospace community world-wide. Clear understanding of the vehicle's operational limitations and flight characteristics in all phases of the flight are preponderant components in developing such a launch system. This dissertation focuses on characterizing and designing the RLV optimal trajectories in order to aid in strategic decision making during mission planning in four areas: 1) nominal ascent phase, 2) abort scenarios and trajectories during ascent phase including abort-to-orbit (ATO), transoceanic-abort-landing (TAL) and return-to-launch-site (RTLS), 3) entry phase (including footprint), and 4) systems engineering aspects of such flight trajectory design. The vehicle chosen for this study is the Lockheed Martin X-33 lifting-body design that lifts off vertically with two linear aerospike rocket engines and lands horizontally. An in-depth investigation of the optimal endo-atmospheric ascent guidance parameters such as earliest abort time, engine throttle setting, number of flight phases, flight characteristics and structural design limitations will be performed and analyzed to establish a set of benchmarks for making better trade-off decisions. Parametric analysis of the entry guidance will also be investigated to allow the trajectory designer to pinpoint relevant parameters and to generate optimal constrained trajectories. Optimal ascent and entry trajectories will be generated using a direct transcription method to cast the optimal control problem as a nonlinear programming problem. The solution to the sparse nonlinear programming problem is then solved using sequential quadratic programming. Finally, guidance system hierarchy studies such as work breakdown structure, functional analysis, fault-tree analysis, and configuration management will be developed to ensure that the guidance system meets the definition of vehicle design requirements and constraints.
Book Synopsis Autonomous Trajectory Planning and Guidance Control for Launch Vehicles by : Zhengyu Song
Download or read book Autonomous Trajectory Planning and Guidance Control for Launch Vehicles written by Zhengyu Song and published by Springer Nature. This book was released on 2023-04-15 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book highlights the autonomous and intelligent flight control of future launch vehicles for improving flight autonomy to plan ascent and descent trajectories onboard, and autonomously handle unexpected events or failures during the flight. Since the beginning of the twenty-first century, space launch activities worldwide have grown vigorously. Meanwhile, commercial launches also account for the booming trend. Unfortunately, the risk of space launches still exists and is gradually increasing in line with the rapidly rising launch activities and commercial rockets. In the history of space launches, propulsion and control systems are the two main contributors to launch failures. With the development of information technologies, the increase of the functional density of hardware products, the application of redundant or fault-tolerant solutions, and the improvement of the testability of avionics, the launch losses caused by control systems exhibit a downward trend, and the failures induced by propulsion systems become the focus of attention. Under these failures, the autonomous planning and guidance control may save the missions. This book focuses on the latest progress of relevant projects and academic studies of autonomous guidance, especially on some advanced methods which can be potentially real-time implemented in the future control system of launch vehicles. In Chapter 1, the prospect and technical challenges are summarized by reviewing the development of launch vehicles. Chapters 2 to 4 mainly focus on the flight in the ascent phase, in which the autonomous guidance is mainly reflected in the online planning. Chapters 5 and 6 mainly discuss the powered descent guidance technologies. Finally, since aerodynamic uncertainties exert a significant impact on the performance of the ascent / landing guidance control systems, the estimation of aerodynamic parameters, which are helpful to improve flight autonomy, is discussed in Chapter 7. The book serves as a valuable reference for researchers and engineers working on launch vehicles. It is also a timely source of information for graduate students interested in the subject.
Book Synopsis Redundant Inertial Measurement Unit Reconfiguration and Trajectory Replanning of Launch Vehicle by : Xuefeng Li
Download or read book Redundant Inertial Measurement Unit Reconfiguration and Trajectory Replanning of Launch Vehicle written by Xuefeng Li and published by Springer Nature. This book was released on 2022-09-22 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book analyzes the problems to be solved urgently in the development of launch vehicle control system. The techniques of redundant Inertial Measurement Unit (IMU) reconfiguration and trajectory replanning are proposed aiming at the inertial device failures and power system failures during flight of launch vehicles, respectively. It introduces the background of redundant IMU reconfiguration and trajectory replanning technologies and models of launch vehicle dynamics and redundant strap-down IMUs. The approaches for redundant strap-down IMU fault detection, reconfiguration and trajectory replanning are proposed, putting forward a prospect for the development of launch vehicle control system. The content of this book is concise and highly pragmatic. It could serve as a reference for engineers and researchers engaged in the analysis, design and verification of launch vehicle control systems and also as a reference for graduate students and senior undergraduates majoring in navigation, guidance and control.
Book Synopsis Analysis of the Staging Maneuver and Booster Glideback Guidance for a Two-stage, Winged, Fully Reusable Launch Vehicle by : J. Christopher Naftel
Download or read book Analysis of the Staging Maneuver and Booster Glideback Guidance for a Two-stage, Winged, Fully Reusable Launch Vehicle written by J. Christopher Naftel and published by . This book was released on 1993 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Flight Test Results of an Adaptive Guidance System for Reusable Launch Vehicles by : John D. Schierman
Download or read book Flight Test Results of an Adaptive Guidance System for Reusable Launch Vehicles written by John D. Schierman and published by . This book was released on 2004 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: To enable autonomous operations in future Reusable Launch Vehicles (RLVs), reconfigurable control and adaptive guidance will often be required to facilitate recovery of the mission following a major anomalous event such as an effector failure. An adaptive guidance system that works in conjunction with a reconfigurable controller and an autonomous trajectory command reshaping algorithm is presented. The guidance law utilizes a backstepping architecture to generate pitch rate commands that drive the inner-loop control system. Under extreme failure conditions the control surfaces can saturate in an attempt to meet commanded moments. In these cases, the guidance feedback gains are reduced to preserve stability margins in the guidance loops. A case study is presented that shows the benefits of the guidance gain adaptation. Without adjusting the gains, the guidance loops go unstable, whereas stability is maintained with gain reduction.
Book Synopsis Optimal Three Dimensional Launch Vehicle Trajectories with Attitude and Attitude Rate Constraints by : Fred Teren
Download or read book Optimal Three Dimensional Launch Vehicle Trajectories with Attitude and Attitude Rate Constraints written by Fred Teren and published by . This book was released on 1969 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aerospace America written by and published by . This book was released on 2005 with total page 732 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis High-Fidelity Real-Time Trajectory Optimization for Reusable Launch Vehicles by : Kevin P. Bollino
Download or read book High-Fidelity Real-Time Trajectory Optimization for Reusable Launch Vehicles written by Kevin P. Bollino and published by . This book was released on 2006 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: Creating simplicity out of complexity, this research abandons the traditional guidance and control architecture for aerospace vehicles and embraces a revolutionary concept based on the principles of nonlinear optimal control theory. Motivated by the emerging needs of the next generation of reusable space vehicles, an autonomous integrated guidance and control system is developed that provides a safe approach to the highly constrained and nonlinear reentry problem. A pseudospectral-based optimal guidance scheme is used to generate high-fidelity, vehicle-tailored solutions to reentry trajectory optimization and guidance problems. To provide an autonomous, onboard capability of satisfying final-approach requirements, a new method is developed that includes an automatic generation of landing constraints given any runway geometry. This unique and simple approach avoids significant complexities arising from previous ideas of trajectory segmentation, trimmed flight, and trajectory tracking schemes. When demonstrating the new ideas, it is shown that the proposed approach can easily compensate for large uncertainties and disturbances consisting of hurricane-force wind gusts. An investigation of these new principles for the complete, nonlinear six degree-of-freedom system dynamics indicates that while the results are quite promising, a substantial amount of new theoretical and computational problems remain open, particularly in the area of over-actuated dynamical systems.
Author :Committee on Reusable Launch Vehicle Technology and Test Program Publisher :National Academies Press ISBN 13 :0309588960 Total Pages :99 pages Book Rating :4.3/5 (95 download)
Book Synopsis Reusable Launch Vehicle by : Committee on Reusable Launch Vehicle Technology and Test Program
Download or read book Reusable Launch Vehicle written by Committee on Reusable Launch Vehicle Technology and Test Program and published by National Academies Press. This book was released on 1996-01-22 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: The key to opening the use of space to private enterprise and to broader public uses lies in reducing the cost of the transportation to space. More routine, affordable access to space will entail aircraft-like quick turnaround and reliable operations. Currently, the space Shuttle is the only reusable launch vehicle, and even parts of it are expendable while other parts require frequent and extensive refurbishment. NASA's highest priority new activity, the Reusable Launch Vehicle program, is directed toward developing technologies to enable a new generation of space launchers, perhaps but not necessarily with single stage to orbit capability. This book assesses whether the technology development, test and analysis programs in propulsion and materials-related technologies are properly constituted to provide the information required to support a December 1996 decision to build the X-33, a technology demonstrator vehicle; and suggest, as appropriate, necessary changes in these programs to ensure that they will support vehicle feasibility goals.
Book Synopsis Maximum-range Trajectories for an Unpowered Reusable Launch Vehicle by : Josiah A. Bryan
Download or read book Maximum-range Trajectories for an Unpowered Reusable Launch Vehicle written by Josiah A. Bryan and published by . This book was released on 2011 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt: A software package has been developed that numerically maximizes the range of an unpowered reusable launch vehicle (RLV) during the Terminal Area Energy Management (TAEM) phase of reentry into Earth's atmosphere by adjusting the angle-of-attack control profile at preselected energy heights along its trajectory. The software computes the optimal trajectory in terms of angle-of-attack deviations from a maximum lift-to-drag trajectory, which is the traditional trajectory used to maximize range of an unpowered aerial vehicle. In order to test the optimization software, an aerodynamic model of the X-34 launch vehicle was developed to calculate lift and drag coefficients for a given angle of attack and Mach number. Consideration of different numbers of control nodes is made, primarily with gradient-based optimization, though particle-swarm optimization is briefly tested. The merits of alternative control laws, such as constant-velocity or constant-dynamic-pressure quasi-equilibrium glide (QEG) algorithms, have also been investigated in an attempt to find a control law that does not require the inherent computational costs associated with numerical optimization. A two-point boundary-value problem is set up using optimal control theory to describe the optimization problem with simplified aerodynamic and atmospheric models.
Book Synopsis Minimum-fuel Optimal Trajectory for Reusable First-stage Rocket Landing Using Particle Swarm Optimization by : Kevin Spencer G. Anglim
Download or read book Minimum-fuel Optimal Trajectory for Reusable First-stage Rocket Landing Using Particle Swarm Optimization written by Kevin Spencer G. Anglim and published by . This book was released on 2016 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Reusable Launch Vehicles (RLVs) present a more environmentally-friendly and cost-effective approach to accessing space when compared to traditional launch vehicles that are discarded after each flight. This paper studies the recyclable nature of RLVs by presenting a solution method for determining minimal-fuel optimal trajectories using principles from optimal control theory and Particle Swarm Optimization (PSO). The problem is formulated as a minimum-fuel, minimum-landing error powered descent problem where it is desired to move the RLV from a fixed set of initial conditions to three different sets of terminal conditions: an unspecified downrange landing, a specified downrange landing, and a return-to-launch-site landing. However, unlike other powered descent studies, this paper considers the highly nonlinear effects caused by atmospheric drag, which are often ignored for similar powered descent studies on the Moon or Mars. Rather than optimize the controls directly, the throttle control is assumed to be bang-off-bang with a predetermined thrust direction for each phase of flight. An overview of optimal control theory and particle swarm optimization is first presented. The PSO method is presented and verified in a one-dimensional comparison study, and is then applied to the two-dimensional cases, the results of which are illustrated.
Book Synopsis Adaptive Guidance Systems for Hypersonic Reusable Launch Vehicles by :
Download or read book Adaptive Guidance Systems for Hypersonic Reusable Launch Vehicles written by and published by . This book was released on 2001 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper presents an adaptive guidance system approach applied to hypersonic Reusable Launch Vehicles (RLVs). After an effector failure, it is assumed that the inner-closed-loop system utilizes a reconfigurable control algorithm to recover nominal maneuvering capabilities to the extent possible. However, nominal performance will typically not be fully recovered for RLVs, and the outer-loop guidance system must account for the degraded vehicle response. Two main approaches for the adaptive guidance system are presented. The first approach augments the existing production guidance system by adding adaptation capabilities. A case study shows that stability is maintained following a primary pitch effector failure. This is achieved by adapting gains in the guidance feedback loops. However, it is shown that the trajectory commands to the guidance loops must also be re-targeted in order to achieve a safe landing. The second approach employs an on-line optimal trajectory re-targeting algorithm. Here, the calculus of variations is used to generate a database of admissible neighboring extremals. This database is then encoded in an efficient manner to generate mappings between the current states and vehicle capabilities and the costates defining the admissible optimal trajectories. These mappings are interrogated on-line at regular intervals to obtain the optimal guidance commands. A proof-of-concept case study of this approach shows that the final landing conditions are achieved following a primary speed control effector failure.