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Book Modeling Control and Coordination of Helicopter Systems

Download or read book Modeling Control and Coordination of Helicopter Systems written by Beibei Ren and published by Springer Science & Business Media. This book was released on 2012-02-02 with total page 243 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modeling, Control and Coordination of Helicopter Systems provides a comprehensive treatment of helicopter systems, ranging from related nonlinear flight dynamic modeling and stability analysis to advanced control design for single helicopter systems, and also covers issues related to the coordination and formation control of multiple helicopter systems to achieve high performance tasks. Ensuring stability in helicopter flight is a challenging problem for nonlinear control design and development. This book is a valuable reference on modeling, control and coordination of helicopter systems,providing readers with practical solutions for the problems that still plague helicopter system design and implementation. Readers will gain a complete picture of helicopters at the systems level, as well as a better understanding of the technical intricacies involved.

Book Helicopter Flight Control System Design Using the Linear Quadratic Regulator for Robust Eigenstructure Assignment

Download or read book Helicopter Flight Control System Design Using the Linear Quadratic Regulator for Robust Eigenstructure Assignment written by and published by . This book was released on 1992 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis applied modern, multi-variable control design techniques, via a FORTRAN computer algorithm, to U.S. Army helicopter models in hovering flight conditions. Eigenstructure assignment and Linear Quadratic Regulator (LQR) theory are used to achieve enhanced closed loop performance and stability characteristics with full state feedback. The addition of cross coupling weights to the standard LQR performance index is specifically addressed. A desired eigenstructure is chosen with a goal of reduced pilot workload via performance qualities requirements. Cross coupling weighting is shown to provide greater flexibility in achieving a desired closed loop eigenstructure. While the addition of cross coupling weighting is shown to eliminate stability margin guarantees associated with LQR methods, the modified algorithm can achieve a closer match to a desired eigenstructure than previous versions of the program while maintaining acceptable stability characteristics.

Book Masters Theses in the Pure and Applied Sciences

Download or read book Masters Theses in the Pure and Applied Sciences written by Wade H. Shafer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Masters Theses in the Pure and Applied Sciences was first conceived, published, and disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS) * at Purdue University in 1 957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all con cerned if the printing and distribution of the volumes were handled by an interna tional publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Cor poration of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 36 (thesis year 1991) a total of 11,024 thesis titles from 23 Canadian and 161 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this important annual reference work. While Volume 36 reports theses submitted in 1991, on occasion, certain univer sities do report theses submitted in previous years but not reported at the time.

Book Linear and Nonlinear Control of Small Scale Unmanned Helicopters

Download or read book Linear and Nonlinear Control of Small Scale Unmanned Helicopters written by Ioannis A. Raptis and published by Springer Science & Business Media. This book was released on 2010-09-28 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: There has been significant interest for designing flight controllers for small-scale unmanned helicopters. Such helicopters preserve all the physical attributes of their full-scale counterparts, being at the same time more agile and dexterous. This book presents a comprehensive and well justified analysis for designing flight controllers for small-scale unmanned helicopters guarantying flight stability and tracking accuracy. The design of the flight controller is a critical and integral part for developing an autonomous helicopter platform. Helicopters are underactuated, highly nonlinear systems with significant dynamic coupling that needs to be considered and accounted for during controller design and implementation. Most reliable mathematical tools for analysis of control systems relate to modern control theory. Modern control techniques are model-based since the controller architecture depends on the dynamic representation of the system to be controlled. Therefore, the flight controller design problem is tightly connected with the helicopter modeling. This book provides a step-by-step methodology for designing, evaluating and implementing efficient flight controllers for small-scale helicopters. Design issues that are analytically covered include: • An illustrative presentation of both linear and nonlinear models of ordinary differential equations representing the helicopter dynamics. A detailed presentation of the helicopter equations of motion is given for the derivation of both model types. In addition, an insightful presentation of the main rotor's mechanism, aerodynamics and dynamics is also provided. Both model types are of low complexity, physically meaningful and capable of encapsulating the dynamic behavior of a large class of small-scale helicopters. • An illustrative and rigorous derivation of mathematical control algorithms based on both the linear and nonlinear representation of the helicopter dynamics. Flight controller designs guarantee that the tracking objectives of the helicopter's inertial position (or velocity) and heading are achieved. Each controller is carefully constructed by considering the small-scale helicopter's physical flight capabilities. Concepts of advanced stability analysis are used to improve the efficiency and reduce the complexity of the flight control system. Controller designs are derived in both continuous time and discrete time covering discretization issues, which emerge from the implementation of the control algorithm using microprocessors. • Presentation of the most powerful, practical and efficient methods for extracting the helicopter model parameters based on input/output responses, collected by the measurement instruments. This topic is of particular importance for real-life implementation of the control algorithms. This book is suitable for students and researches interested in the development and the mathematical derivation of flight controllers for small-scale helicopters. Background knowledge in modern control is required.

Book Helicopter Flight Dynamics

Download or read book Helicopter Flight Dynamics written by Gareth D. Padfield and published by John Wiley & Sons. This book was released on 2008-04-15 with total page 681 pages. Available in PDF, EPUB and Kindle. Book excerpt: The behaviour of helicopters is so complex that understanding the physical mechanisms at work in trim, stability and response, and thus the prediction of Flying Qualities, requires a framework of analytical and numerical modelling and simulation. Good Flying Qualities are vital for ensuring that mission performance is achievable with safety and, in the first edition of Helicopter Flight Dynamics, a comprehensive treatment of design criteria was presented. In this second edition, the author complements this with a new Chapter on Degraded Flying Qualities, drawing examples from flight in poor visibility, failure of control functions and encounters with severe atmospheric disturbances. Fully embracing the consequences of Degraded Flying Qualities during the design phase will contribute positively to safety. The accurate prediction and assessment of Flying Qualities draws on the modelling and simulation discipline on the one hand and testing methodologies on the other. Checking predictions in flight requires clearly defined ‘mission-task-elements’, derived from missions with realistic performance requirements. High fidelity simulations also form the basis for the design of stability and control augmentation systems, essential for conferring Level 1 Flying Qualities. The integrated description of flight dynamic modelling, simulation and flying qualities forms the subject of this book, which will be of interest to engineers in research laboratories and manufacturing industry, test pilots and flight test engineers, and as a reference for graduate and postgraduate students in aerospace engineering. The Author Gareth Padfield, a Fellow of the Royal Aeronautical Society, is the Bibby Professor of Aerospace Engineering at the University of Liverpool. He is an aeronautical engineer by training and has spent his career to date researching the theory and practice of flight for both fixed-wing aeroplanes and rotorcraft. During his years with the UK’s Royal Aircraft Establishment and Defence Evaluation and Research Agency, he conducted research into rotorcraft dynamics, handling qualities and flight control. His work has involved a mix of flight testing, creating and testing simulation models and developing analytic approximations to describe flight behaviour and handling qualities. Much of his research has been conducted in the context of international collaboration – with the Technical Co-operation Programme, AGARD and GARTEUR as well as more informal collaborations with industry, universities and research centres worldwide. He is very aware that many accomplishments, including this book, could not have been achieved without the global networking that aerospace research affords. During the last 8 years as an academic, the author has continued to develop his knowledge and understanding in flight dynamics, not only through research, but also through teaching the subject at undergraduate level; an experience that affords a new and deeper kind of learning that, hopefully, readers of this book will benefit from.

Book Flight Simulation of the Model 347 Advanced Tandem rotor Helicopter

Download or read book Flight Simulation of the Model 347 Advanced Tandem rotor Helicopter written by U.S. Army Air Mobility Research and Development Laboratory. Eustis Directorate and published by . This book was released on 1974 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Design of a Multivariable Helicopter Flight Control System for Handling Qualities Enhancement

Download or read book Design of a Multivariable Helicopter Flight Control System for Handling Qualities Enhancement written by and published by . This book was released on 1990 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: New handling qualities specifications are currently being developed for attack helicopters. Most unaugmented helicopters will not meet these specifications and feedback control is necessary to improve handling qualities so that safe operation close to the earth in poor weather conditions and/or at night is possible. In this paper a methodology for the direct design of helicopter flight control systems which meet handling qualities specifications is presented. This methodology uses full state feedback to place closed loop eigenvalues to achieve bandwidth specifications and to shape closed loop eigenvectors to decouple lateral and longitudinal responses to control inputs. Full state feedback requires that all state variables be known; however, only angular rates and normal acceleration are measured by sensors. Thus, a state estimator is required in the feedback loop in order to convert sensor outputs to control inputs. This estimator is designed using eigenstructure assignment so as to achieve loop transfer recovery. Design of a feedback system for use in precise hovering control for a modern attack helicopter is used to illustrate the method. Control law synthesis is accomplished using an eighth order model which includes only rigid body modes. Control law performance is evaluated using a 37th order model which includes rigid body, actuator, rotor, sensor, and flexure dynamics. It is found that a notch filter must be added to the design in order to eliminate a high frequency instability. Once this is accomplished, both the time and frequency response characteristics of the augmented helicopter are much improved compared with the unaugmented helicopter.

Book Procedural Guide for Modeling and Analyzing the Flight Dynamics of the SH 60B Helicopter Using Flightlab

Download or read book Procedural Guide for Modeling and Analyzing the Flight Dynamics of the SH 60B Helicopter Using Flightlab written by Roy C. Wagner and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis uses Flightlab to model and analyze the flight dynamics of the SH-6OB Seahawk helicopter. Flightlab runs on computers utilizing the UNIX operating system and is used for design, analysis and testing of an aircraft using non-linear modeling techniques. It is capable of modeling conventional main rotor-tail rotor and tandem rotor helicopters and tilt rotor aircraft. A procedural guide for modeling and analyzing a single main rotor helicopter is presented using the SH-60B. The non-linear response from lateral and longitudinal cyclic, main rotor collective and tail rotor collective inputs are presented. Flightlab is also capable of reducing the non-linear model to a linear model. The linear and non-linear models are then compared. The purpose of this thesis is to present a guide for using Flightlab to model and analyze an existing helicopter design, and also to have in place a well tested model to be used for further research.

Book Procedural Guide for Modeling and Analyzing the Flight Dynamics of the SH 60B Helicopter Using Flightlab

Download or read book Procedural Guide for Modeling and Analyzing the Flight Dynamics of the SH 60B Helicopter Using Flightlab written by Roy C. Wagner and published by . This book was released on 1995 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis uses Flightlab to model and analyze the flight dynamics of the SH-6OB Seahawk helicopter. Flightlab runs on computers utilizing the UNIX operating system and is used for design, analysis and testing of an aircraft using non-linear modeling techniques. It is capable of modeling conventional main rotor-tail rotor and tandem rotor helicopters and tilt rotor aircraft. A procedural guide for modeling and analyzing a single main rotor helicopter is presented using the SH-60B. The non-linear response from lateral and longitudinal cyclic, main rotor collective and tail rotor collective inputs are presented. Flightlab is also capable of reducing the non-linear model to a linear model. The linear and non-linear models are then compared. The purpose of this thesis is to present a guide for using Flightlab to model and analyze an existing helicopter design, and also to have in place a well tested model to be used for further research.

Book Helicopter Flight Dynamics

Download or read book Helicopter Flight Dynamics written by Gareth D. Padfield and published by John Wiley & Sons. This book was released on 2018-11-19 with total page 858 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Book The behaviour of helicopters and tiltrotor aircraft is so complex that understanding the physical mechanisms at work in trim, stability and response, and thus the prediction of Flying Qualities, requires a framework of analytical and numerical modelling and simulation. Good Flying Qualities are vital for ensuring that mission performance is achievable with safety and, in the first and second editions of Helicopter Flight Dynamics, a comprehensive treatment of design criteria was presented, relating to both normal and degraded Flying Qualities. Fully embracing the consequences of Degraded Flying Qualities during the design phase will contribute positively to safety. In this third edition, two new Chapters are included. Chapter 9 takes the reader on a journey from the origins of the story of Flying Qualities, tracing key contributions to the developing maturity and to the current position. Chapter 10 provides a comprehensive treatment of the Flight Dynamics of tiltrotor aircraft; informed by research activities and the limited data on operational aircraft. Many of the unique behavioural characteristics of tiltrotors are revealed for the first time in this book. The accurate prediction and assessment of Flying Qualities draws on the modelling and simulation discipline on the one hand and testing practice on the other. Checking predictions in flight requires clearly defined mission tasks, derived from realistic performance requirements. High fidelity simulations also form the basis for the design of stability and control augmentation systems, essential for conferring Level 1 Flying Qualities. The integrated description of flight dynamic modelling, simulation and flying qualities of rotorcraft forms the subject of this book, which will be of interest to engineers practising and honing their skills in research laboratories, academia and manufacturing industries, test pilots and flight test engineers, and as a reference for graduate and postgraduate students in aerospace engineering.

Book Procedural Guide for Modelling and Analyzing the Flight Characteristics of a Helicopter Design Using Flightlab

Download or read book Procedural Guide for Modelling and Analyzing the Flight Characteristics of a Helicopter Design Using Flightlab written by Gary P. McVaney and published by . This book was released on 1993 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents one method for modelling and analyzing a helicopter design using Flightlab. Flightlab is a computer program that provides for engineering design, analysis and simulation of aircraft using non-linear dynamic modeling techniques. The procedure to model a single main rotor helicopter is outlined using the sample helicopter design in the book 'Helicopter Performance, Stability, and Control' by Ray Prouty. The analysis procedure contains computer program scripts for determining the time response of the helicopter to standard control inputs such as a longitudinal impulse, a lateral step, and a pedal doublet. A linear model of the helicopter can be extracted from the non-linear model, and a comparison of the time response to the control inputs based on these two models is presented. The procedure for conducting frequency sweep testing for the linear model is also discussed. This guide to using Flightlab for aircraft modelling and analysis is designed to make it easier to use Flightlab for creating additional aircraft models for use in control system analysis and additional engineering design.

Book Eigenspace Design of Helicopter Flight Control Systems

Download or read book Eigenspace Design of Helicopter Flight Control Systems written by and published by . This book was released on 1990 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: An eigenstructure based design methodology for helicopter flight control systems is developed and evaluated in this report. The report provides a detailed review of the application of multivariable design techniques to helicopter flight control systems, a review of applicable handling quality specifications, a description of the mathematical models used, a presentation of the theory of eigenstructure design, application of the theory to a helicopter design problem, and evaluation of the performance and robustness properties of the resulting control laws.

Book Helicopter Mathematical Models and Control Law Development for Handling Qualities Research

Download or read book Helicopter Mathematical Models and Control Law Development for Handling Qualities Research written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-10 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Progress made in joint NASA/Army research concerning rotorcraft flight-dynamics modeling, design methodologies for rotorcraft flight-control laws, and rotorcraft parameter identification is reviewed. Research into these interactive disciplines is needed to develop the analytical tools necessary to conduct flying qualities investigations using both the ground-based and in-flight simulators, and to permit an efficient means of performing flight test evaluation of rotorcraft flying qualities for specification compliance. The need for the research is particularly acute for rotorcraft because of their mathematical complexity, high order dynamic characteristics, and demanding mission requirements. The research in rotorcraft flight-dynamics modeling is pursued along two general directions: generic nonlinear models and nonlinear models for specific rotorcraft. In addition, linear models are generated that extend their utilization from 1-g flight to high-g maneuvers and expand their frequency range of validity for the design analysis of high-gain flight control systems. A variety of methods ranging from classical frequency-domain approaches to modern time-domain control methodology that are used in the design of rotorcraft flight control laws is reviewed. Also reviewed is a study conducted to investigate the design details associated with high-gain, digital flight control systems for combat rotorcraft. Parameter identification techniques developed for rotorcraft applications are reviewed. Chen, Robert T. N. and Lebacqz, J. Victor and Aiken, Edwin W. and Tischler, Mark B. Ames Research Center...