Download or read book Robust Nonlinear Feedback Control of Aircraft Propulsion Systems written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-13 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the final report on the research performed under NASA Glen grant NASA/NAG-3-1975 concerning feedback control of the Pratt & Whitney (PW) STF 952, a twin spool, mixed flow, after burning turbofan engine. The research focussed on the design of linear and gain-scheduled, multivariable inner-loop controllers for the PW turbofan engine using H-infinity and linear, parameter-varying (LPV) control techniques. The nonlinear turbofan engine simulation was provided by PW within the NASA Rocket Engine Transient Simulator (ROCETS) simulation software environment. ROCETS was used to generate linearized models of the turbofan engine for control design and analysis as well as the simulation environment to evaluate the performance and robustness of the controllers. Comparison between the H-infinity, and LPV controllers are made with the baseline multivariable controller and developed by Pratt & Whitney engineers included in the ROCETS simulation. Simulation results indicate that H-infinity and LPV techniques effectively achieve desired response characteristics with minimal cross coupling between commanded values and are very robust to unmodeled dynamics and sensor noise. Garrard, William L. and Balas, Gary J. and Litt, Jonathan (Technical Monitor) Glenn Research Center NAG3-1975

Download or read book Robust Nonlinear Control of Vectored Thrust Aircraft written by John Comstock Doyle and published by . This book was released on 1993 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hierarchical Robust Nonlinear Switching Control Design for Propulsion Systems written by Alexander Leonessa and published by . This book was released on 1999 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Robust Control written by Jürgen Ackermann and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt: New results, fresh ideas and new applications in automotive and flight control systems are presented in this second edition of Robust Control. The book presents parametric methods and tools for the simultaneous design of several representative operating conditions and several design specifications in the time and frequency domains. It also covers methods for robustness analysis that guarantee the desired properties for all possible values of the plant uncertainty. A lot of practical application experience enters into the case studies of driver support systems that avoid skidding and rollover of cars, automatic car steering systems, flight controllers for unstable aircraft and engine-out controllers. The book also shows the historic roots of the methods, their limitations and research needs in robust control.

Download or read book Robust and Adaptive Control written by Eugene Lavretsky and published by Springer Nature. This book was released on 2023 with total page 718 pages. Available in PDF, EPUB and Kindle. Book excerpt: Zusammenfassung: Robust and Adaptive Control (second edition) shows readers how to produce consistent and accurate controllers that operate in the presence of uncertainties and unforeseen events. Driven by aerospace applications, the focus of the book is primarily on continuous-time dynamical systems. The two-part text begins with robust and optimal linear control methods and moves on to a self-contained presentation of the design and analysis of model reference adaptive control for nonlinear uncertain dynamical systems. Features of the second edition include: sufficient conditions for closed-loop stability under output feedback observer-based loop-transfer recovery (OBLTR) with adaptive augmentation; OBLTR applications to aerospace systems; case studies that demonstrate the benefits of robust and adaptive control for piloted, autonomous and experimental aerial platforms; realistic examples and simulation data illustrating key features of the methods described; and problem solutions for instructors and MATLAB® code provided electronically. The theory and practical applications address real-life aerospace problems, being based on numerous transitions of control-theoretic results into operational systems and airborne vehicles drawn from the authors' extensive professional experience with The Boeing Company. The systems covered are challenging--often open-loop unstable with uncertainties in their dynamics--and thus require both persistently reliable control and the ability to track commands either from a pilot or a guidance computer. Readers should have a basic understanding of root locus, Bode diagrams, and Nyquist plots, as well as linear algebra, ordinary differential equations, and the use of state-space methods in analysis and modeling of dynamical systems. The second edition contains a background summary of linear systems and control systems and an introduction to state observers and output feedback control, helping to make it self-contained. Robust and Adaptive Control teaches senior undergraduate and graduate students how to construct stable and predictable control algorithms for realistic industrial applications. Practicing engineers and academic researchers will also find the book of great instructional value

Download or read book Robust Nonlinear Control System Design for Hypersonic Flight Vehicles written by Obaid Ur Rehman and published by . This book was released on 2011 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis develops a new nonlinear robust control design procedure which addresses some of the challenges associated with the control of uncertain nonlinear system and applies the proposed method to tracking control of an Air-breathing Hypersonic Flight Vehicle (AHFV). The AHFV is a highly nonlinear system and the combination of nonlinear dynamics, parameter uncertainty and complex constraints make the flight control design a challenging task for this type of vehicle. The main contribution of this thesis lies in the fact that it presents a robust feedback linerization based strategy which solves the control issue of a class of nonlinear systems subject to parametric uncertainty. The method is effectively applied to the tracking control of an AHFV. It is also demonstrated that the proposed approach can be used to design a single robust controller for a large flight envelope rather than using several gain scheduled controllers. This research, firstly presents three different approaches to develop linearized uncertainty models for a class of nonlinear systems using a robust feedback lnearization method. The feedback linearization approach to linearize the nonlinear dynamics has some advantages over the point linearization (Jacobian linearization) method. However, the feedback linearization method only linearizes the nominal model of a system and in the presence of uncertainty in the model the exact linearization is not possible. In this thesis, we present a robust approach to deal with the nonlinearities arising from the uncertainties in the system and use a nonlinear AHFV model to demonstrate the effectiveness of the method. Besides parametric uncertainty, due to the presence of body-integrated propulsion system, and the flexible modes, the nonlinear model of AHFV does not possess full relative degree. Any attempt to feedback linearize this nonlinear model will result into having input term in low order derivatives of the system output. In this research, we strategically remove the coupling and flexible effects from the nonlinear model and simplify the model in such a way that the full relative degree condition is satisfied. In the development of linearized uncertainty model for an AHFV the conventional feedback linearization approach is used to remove the known nonlinearities from the simplified system model and the nonlinearities arising from the uncertainties are treated in three different ways. In the first method, nonlinear uncertainties are linearized using Taylor expansion at an arbitrary point by considering a structured representation of uncertainties. This lienarization approach approximates the actual nonlinear uncertainty by considering only the first order terms and neglecting all the higher order terms. For the linearized model, a minimax Linear Quadratic Regulator (LQR) controller combined with feedback linearization law is proposed to fulfill the velocity and altitude tracking requirements of an AHFV. In the second method, an unstructured uncertainty representation is considered and a minimax Linear Quadratic Gaussian (LQG) controller combined with feedback linearization law is proposed for the same tracking requirements. In the third, method the nonlinear uncertainty terms are linearized at an arbitrary point using the generalized mean value theorem. The main advantages of using this approach are that upper bound on the uncertainties can be obtained by both structured and unstructured uncertainty representations and there is no need to ignore higher order uncertainty terms. The uncertain linearized models obtained from this method are followed by guaranteed cost and minimax LQR controllers combined with feedback linearization law. Rigorous simulations using actual nonlinear model for all the above methods are presented in the thesis to analyze the effectiveness of these controllers. These simulations have considered several cases of uncertainties for a step change in the reference commands. In order to see the robustness properties of the proposed robust scheme a Monte-Calro based simulation is also presented by considering the given bound on the uncertain parameters. Also, in order to demonstrate the effectiveness of the approach for a large flight envelope, several simulations are performed to observe the tracking response for the given reference trajectories in a large flight envelope.

Download or read book Robust Nonlinear Control of Vectored Thrust Aircraft written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-11 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: An interdisciplinary program in robust control for nonlinear systems with applications to a variety of engineering problems is outlined. Major emphasis will be placed on flight control, with both experimental and analytical studies. This program builds on recent new results in control theory for stability, stabilization, robust stability, robust performance, synthesis, and model reduction in a unified framework using Linear Fractional Transformations (LFT's), Linear Matrix Inequalities (LMI's), and the structured singular value micron. Most of these new advances have been accomplished by the Caltech controls group independently or in collaboration with researchers in other institutions. These recent results offer a new and remarkably unified framework for all aspects of robust control, but what is particularly important for this program is that they also have important implications for system identification and control of nonlinear systems. This combines well with Caltech's expertise in nonlinear control theory, both in geometric methods and methods for systems with constraints and saturations. Doyle, John C. and Murray, Richard and Morris, John Unspecified Center NAG2-792...

Download or read book Robust Control written by Jürgen Ackermann and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many plants have large variations in operating conditions. To ensure smooth running it is essential to find a simple fixed gain controller that guarantees rapidly decaying and well-damped transients for all admissible operating conditions. Robust Control presents design tools, developed by the authors, for the solution of this design problem. Examples of simple and complex cases such as a crane, a flight control problem and the automatic and active four-wheel steering of a car illustrate the use of these tools. This book is intended for anyone who has taken an undergraduate course in feedback control systems and who seeks an advanced treatment of robust control with applications. Drawing on the resources and authoritative research of a leading aerospace institute, it will mainly be of interest to mechanical and electrical engineers in universities, institutes and industrial research centres.

Download or read book Robust Multivariable Flight Control written by Richard J. Adams and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: Manual flight control system design for fighter aircraft is one of the most demanding problems in automatic control. Fighter aircraft dynamics generally have highly coupled uncertain and nonlinear dynamics. Multivariable control design techniques offer a solution to this problem. Robust Multivariable Flight Control provides the background, theory and examples for full envelope manual flight control system design. It gives a versatile framework for the application of advanced multivariable control theory to aircraft control problems. Two design case studies are presented for the manual flight control of lateral/directional axes of the VISTA-F-16 test vehicle and an F-18 trust vectoring system. They demonstrate the interplay between theory and the physical features of the systems.

Download or read book Stability and Control of Aircraft Systems written by Roy Langton and published by John Wiley & Sons. This book was released on 2006-11-02 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the current climate of increasing complexity and functional integration in all areas of engineering and technology, stability and control are becoming essential ingredients of engineering knowledge. Many of today’s products contain multiple engineering technologies, and what were once simple mechanical, hydraulic or pneumatic products now contain integrated electronics and sensors. Control theory reduces these widely varied technical components into their important dynamic characteristics, expressed as transfer functions, from which the subtleties of dynamic behaviours can be analyzed and understood. Stability and Control of Aircraft Systems is an easy-to-read and understand text that describes control theory using minimal mathematics. It focuses on simple rules, tools and methods for the analysis and testing of feedback control systems using real systems engineering design and development examples. Clarifies the design and development of feedback control systems Communicates the theory in an accessible manner that does not require the reader to have a strong mathematical background Illustrated throughout with figures and tables Stability and Control of Aircraft Systems provides both the seasoned engineer and the graduate with the know-how necessary to minimize problems with fielded systems in the area of operational performance.

Download or read book Robust Nonlinear Feedback Guidance for an Aerospace Plane written by Markus Antonius Van Buren and published by . This book was released on 1992 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Model based Nonlinear Control of Aeroengines written by Jiqiang Wang and published by Springer Nature. This book was released on 2021-08-17 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book aims to develop systematic design methodologies to model-based nonlinear control of aeroengines, focusing on (1) modelling of aeroengine systems—both component-level and identification-based models will be extensively studied and compared; and (2) advanced nonlinear control designs—set-point control, transient control and limit-protection control approaches will all be investigated. The model-based design has been one of the pivotal technologies to advanced control and health management of propulsion systems. It can fulfil advanced designs such as fault-tolerant control, engine modes control and direct thrust control. As a consequence, model-based design has become an important research area in the field of aeroengines due to its theoretical interests and engineering significance. One of the central issues in model-based controls is the tackling of nonlinearities. There are publications concerning with either nonlinear modelling or nonlinear controls; yet, they are scattered throughout the literature. It is time to provide a comprehensive summary of model-based nonlinear controls. Consequently, a series of important results are obtained and a systematic design methodology is developed which provides consistently enhanced performance over a large flight/operational envelope, and it is thus expected to provide useful guidance to practical engineering in aeroengine industry and research.

Download or read book Advanced Control of Turbofan Engines written by Hanz Richter and published by Springer Science & Business Media. This book was released on 2011-10-20 with total page 275 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced Control of Turbofan Engines describes the operational performance requirements of turbofan (commercial) engines from a controls systems perspective, covering industry-standard methods and research-edge advances. This book allows the reader to design controllers and produce realistic simulations using public-domain software like CMAPSS: Commercial Modular Aero-Propulsion System Simulation, whose versions are released to the public by NASA. The scope of the book is centered on the design of thrust controllers for both steady flight and transient maneuvers. Classical control theory is not dwelled on, but instead an introduction to general undergraduate control techniques is provided. Advanced Control of Turbofan Engines is ideal for graduate students doing research in aircraft engine control and non-aerospace oriented control engineers who need an introduction to the field.

Download or read book Robust Multivariable Control of Aerospace Systems written by Declan Bates and published by IOS Press. This book was released on 2002 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Classical design and analysis techniques, many of which date back to the 1950's, are still predominantly used in the aerospace industry for the design and analysis of automatic flight control and aero-engine control systems. The continued success and popularity of these techniques is particularly impressive considering the radical advances in aircraft and spacecraft design and avionics technology made over this period. Clearly, an understanding of both the advantages and limitations of these methods is essential in order to properly evaluate the likely usefulness of more modern techniques for the design and analysis of aerospace control systems. One of the themes of this book is that the multivariable robust control methods it describes are logical and natural extensions of the more classical methods, and not replacements for them. It is assumed that readers of this publication are already familiar with classical flight control techniques. Emphasis is on the philosophy, advantages and limitations of the classical approach to flight control system design and analysis. Abstracted in Inspec

Download or read book Robust Nonlinear Control Theory with Applications to Aerospace Vehicles written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The focus of this program is fundamental research in general methods of analysis and design of complex uncertain nonlinear systems. The approach builds on our recent success in blending robust and nonlinear control methods with a much greater emphasis on the use of local and global techniques in nonlinear dynamical systems theory. Specific areas of accomplishment include real-time trajectory generation for unmanned aerial vehicles, geometric mechanics and nonlinear stabilization, linear parameter varying control, and unified techniques for stabilization of nonlinear systems that combine model predictive control techniques with control Lyapunov function techniques. In addition, the program explored techniques for modeling and control of chemically reacting systems, with applications to gas turbine engines and materials growth.

Download or read book An Investigation of Nonlinear Controller for Propulsion Controlled Aircraft written by National Aeronautics and Space Adm Nasa and published by . This book was released on 2018-10-22 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aircraft control systems are usually very reliable because of redundancy and multiple control surfaces. However, there are rare occasions when potentially disastrous flight control system failures do occur. At such times, the use of appropriate modulation of engine thrust to stabilize the aircraft may be the only chance of survival for the people aboard. In several cases where complete loss of control systems has occurred in multi-engine aircraft, pilots used the propulsion system to regain limited control of the aircraft with various degrees of success. In order to evaluate the feasibility of using only engine thrust modulation for emergency backup flight control, the NASA Dryden Flight Research Center has been conducting a series of analytical studies and flight tests on several different types of aircraft in a propulsion controlled aircraft (PCA) program. Simulation studies have included B-720, B-727, MD-11, C-402, C-17, F-18, and F-15, and flight tests have included B-747, B-777, MD-11, T-39, Lear 24, F-18, F-15, T-38, and PA-30. One objective was to determine the degree of control available with manual manipulation (open-loop) of the engine throttles. Flight tests and simulations soon showed that a closed loop controller could improve the chances of making a safe runway landing. The major work to date has concentrated on three aircraft (F-15, F-18, and the MD-11). Successful landings using PCA controllers were performed on the F-15 and MD-11 without the use of control surfaces. During the course of the research, some unique challenges have been identified. Compared to the conventional flight control surfaces, the engines are slow and have limited control effectiveness. Hence the ability of the system to promptly respond to aerodynamic changes is limited. Consequently, many nonlinear effects, which are easily accommodated by a conventional flight control system, become significant issues in the design of an effective controller when the engines are used as the o...

Download or read book Applications of Robust Control to Nonlinear Systems written by Richard Dean Colgren and published by AIAA. This book was released on 2004 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: