Optimal Trajectory Reconfiguration And Retargeting For The X 33 Reusable Launch Vehicle
DOWNLOAD
Download Optimal Trajectory Reconfiguration And Retargeting For The X 33 Reusable Launch Vehicle PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get Optimal Trajectory Reconfiguration And Retargeting For The X 33 Reusable Launch Vehicle book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page
Optimal Trajectory Reconfiguration And Retargeting For The X 33 Reusable Launch Vehicle
DOWNLOAD
Author : Patrick J. Shaffer
language : en
Publisher:
Release Date : 2004-09-01
Optimal Trajectory Reconfiguration And Retargeting For The X 33 Reusable Launch Vehicle written by Patrick J. Shaffer and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2004-09-01 with categories.
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.
Fault Tolerant Optimal Trajectory Generation For Reusable Launch Vehicles
DOWNLOAD
Author : Patrick J. Shaffer
language : en
Publisher:
Release Date : 2006
Fault Tolerant Optimal Trajectory Generation For Reusable Launch Vehicles written by Patrick J. Shaffer and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2006 with Launch vehicles (Astronautics) categories.
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.
Journal Of Guidance Control And Dynamics
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2007
Journal Of Guidance Control And Dynamics written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2007 with Airplanes categories.
Optimal Trajectory Reconfiguration And Retargeting For A Reusable Launch Vehicle
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2005
Optimal Trajectory Reconfiguration And Retargeting For A Reusable Launch Vehicle written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2005 with categories.
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.
Optimal Trajectory Designs And Systems Engineering Analyses Of Reusable Launch Vehicles
DOWNLOAD
Author : Hung-i Bruce Tsai
language : en
Publisher:
Release Date : 2003
Optimal Trajectory Designs And Systems Engineering Analyses Of Reusable Launch Vehicles written by Hung-i Bruce Tsai and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2003 with categories.
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.
Reusable Launch Vehicle
DOWNLOAD
Author : Committee on Reusable Launch Vehicle Technology and Test Program
language : en
Publisher: National Academies Press
Release Date : 1996-01-22
Reusable Launch Vehicle written by Committee on Reusable Launch Vehicle Technology and Test Program and has been published by National Academies Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 1996-01-22 with Science categories.
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.
A Reconfigurable Guidance Approach For Reusable Launch Vehicles
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2001
A Reconfigurable Guidance Approach For Reusable Launch Vehicles written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2001 with categories.
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.
Optimal Guidance Command Generation And Tracking For Reusable Launch Vehicle Reentry Preprint
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2006
Optimal Guidance Command Generation And Tracking For Reusable Launch Vehicle Reentry Preprint written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2006 with categories.
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.
Redundant Inertial Measurement Unit Reconfiguration And Trajectory Replanning Of Launch Vehicle
DOWNLOAD
Author : Xuefeng Li
language : en
Publisher:
Release Date : 2023
Redundant Inertial Measurement Unit Reconfiguration And Trajectory Replanning Of Launch Vehicle written by Xuefeng Li and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2023 with categories.
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.
Maximum Range Trajectories For An Unpowered Reusable Launch Vehicle
DOWNLOAD
Author : Josiah A. Bryan
language : en
Publisher:
Release Date : 2011
Maximum Range Trajectories For An Unpowered Reusable Launch Vehicle written by Josiah A. Bryan and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2011 with Electronic Dissertations categories.
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.