Дисертації з теми "Helicopter dynamic systems"
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Kontitsis, Michail. "Design and implementation of an integrated dynamic vision system for autonomous systems operating in uncertain domains." [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0002852.
Повний текст джерелаSamal, Mahendra Engineering & Information Technology Australian Defence Force Academy UNSW. "Neural network based identification and control of an unmanned helicopter." Awarded by:University of New South Wales - Australian Defence Force Academy. Engineering & Information Technology, 2009. http://handle.unsw.edu.au/1959.4/43917.
Повний текст джерелаLopes, Darby Freitas de Albuquerque. "Estimativa da atitude e posição e controle robusto de um helicóptero autônomo." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/18/18153/tde-08022011-095400/.
Повний текст джерелаThis work concerns the study of an inertial reference system and a control system for an autonomous helicopter using, as basis for the formulation and testing, the linearized mo del of the aircraft Yamaha R-MAX. An inertial navigation system (INS) and an attitude and orientation reference system (AHRS) are used to estimate the position and attitude of the aircraft and robust estimators based on Kalman filter are employed to minimize the effects of parametric uncertainties. A cascaded control architecture with three control methodologies is used, consisting of an inner-loop to ensure stability of the helicopter (the LQR and H \'INFINITE\' techniques are used, separately), a mid-loop based on linearization feedback (FLC) to decouple the dynamics ofthe lateral, longitudinal, vertical and heading axes and an outer-loop based on a proportional-derivative (PD) controller to enable trajectory tracking. Simulation results are presented to evaluate the performance of each approach.
Guivarch, Damien. "Méthodes et outils d'aide à l'estimation des efforts sur les ensembles mécaniques en phase d'architecture. Application aux hélicoptères." Electronic Thesis or Diss., Toulouse, INSA, 2019. http://www.theses.fr/2019ISAT0053.
Повний текст джерелаNew software tools are used to simulate the transient dynamic behaviour of multi-body mechanical systems. Could they provide a good forecast of loads applied on helicopter rotary wing system? The work developed in this thesis provides some answers to this question, knowing that the context considered presents many difficulties: flexible bodies, complex mechanical links, hyperstatisms… The stakes are high because the development cycle of these mechanical assemblies would be greatly reduced by a correct estimation of loads during the first steps of the design of a new architecture. In this context, a new level of modeling is introduced, focusing on the dynamic systems studied. Since this level is part of a multi-scale approach, it is necessary to feed it with simplified models of the subassemblies that form the studied system, and this leads to so-called local studies. The presentation of this work is based on the rotary wing system of H160 helicopter, currently in industrialization phase at Airbus Helicopters, which includes the blades, the main rotor and the hydraulic control actuators. Three major developments are detailed: modelling of a swashplates sub-assembly, blades and the rotary wing system.The new modelling framework thus created allows the loads estimation at the level of the mechanical links of these systems and the monitoring of their evolution over time
Potter, James Jackson. "Input-shaped manual control of helicopters with suspended loads." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50342.
Повний текст джерелаMittal, Manoj. "Modeling and control of a twin-lift helicopter system." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/12174.
Повний текст джерелаBangalore, Ashok K. "Computational fluid dynamic studies of high lift rotor systems using distributed computing." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/12949.
Повний текст джерелаNygren, Kip P. "An investigation of helicopter higher harmonic control using a dynamic system coupler simulation." Diss., Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/12082.
Повний текст джерелаWeiner, Steven David 1956. "The effect of improved aircraft efficiency on helicopter sales using system dynamics." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/91712.
Повний текст джерелаBrown, Sean M. "Determination of Human Powered Helicopter Stability Characteristics using Multi-Body System Simulation Techniques." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/874.
Повний текст джерелаPatrick-Aldaco, Romano. "A Model Based Framework for Fault Diagnosis and Prognosis of Dynamical Systems with an Application to Helicopter Transmissions." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/16266.
Повний текст джерелаLayshot, Nicholas Joseph. "MODELING OF A GYRO-STABILIZED HELICOPTER CAMERA SYSTEM USING NEURAL NETWORKS." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/421.
Повний текст джерелаSumer, Yalcin Faik. "Predictive Control of Multibody Systems for the Simulation of Maneuvering Rotorcraft." Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6940.
Повний текст джерелаMcLucas, Alan Charles Civil Engineering Australian Defence Force Academy UNSW. "An investigation into the integration of qualitative and quantitative techniques for addressing systemic complexity in the context of organisational strategic decision-making." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Civil Engineering, 2001. http://handle.unsw.edu.au/1959.4/38744.
Повний текст джерелаRodriguez, Jonathan. "Contrôle actif d’une suspension de boîte de transmission principale d’hélicoptère." Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0033.
Повний текст джерелаOne of the main causes of discomfort in helicopters are the vibrations transmitted from the rotor to the structure. In forward flight, the blades are submitted to cyclic aerodynamic loads which generate low frequency (around 17Hz) but high energy mechanical vibrations. These vibrations are transmitted from the rotor to the main gearbox, then to the structure and finally to the crew and passengers. In order to maintain acceptable comfort for crew members and passengers, a lot of antivibration devices have been developed since the last 30 years. These systems are generally passive because most of the mechanical energy transmitted to the structure is at only one frequency ωc which is equal to the product bΩ with b the number of blades and Ω the rotor rotational speed. However, modern helicopters evolve and the rotor rpm, which has always been considered as fixed during flight is now a function of time, depending on the flight phases in order to increase performances and reduce energy consumption (variation bandwidth of Ω +/- 10%). This new constraint on the design of helicopters makes the active antivibration technology completely relevant with its capacity to adapt in terms of amplitude and frequency to the perturbation. During this thesis, the passive suspension called SARIB from Airbus Helicopters, based on the DAVI principle (Dynamic Antiresonant Vibration Isolator) is modified in order to implement active components and command (actuation). The theory of the control algorithms used in this thesis is presented in detail in order to define the theoretical tools of the active DAVI control which are : FXLMS control (adaptive control) and LQG (optimal control). To simulate the complete system, a 3D multibody model of the active suspension has been set up, coupled to a the flexible structure of a NH90 (Airbus Helicopters). On this model are applied the different control algorithms presented before and their performances are compared for different loads with variable frequency on the rotor hub. In the same way, different locations for the error sensors in the structure are studied to find the optimal control configuration. The simulations show that the FXLMS algorithm is well suited for the control of harmonic perturbations and reduce significantly the dynamic acceleration level on the cabin floor, without parasite reinjection on other parts of the structure. A comparison of the active SARIB with classical cabin vibration absorbers is also made in terms of efficiency in order to show the advantages of using the DAVI system as a base for an active antivibration device. Finally, this thesis also presents the experiments realized in the dynamics laboratory of Airbus Helicopters on a 1:1 scale prototype of the active SARIB suspension with FXLMS control. The results demonstrate the efficiency of the active suspension architecture and control algorithms
Johnson, Kevin Lee. "Prediction of operational envelope maneuverability effects on rotorcraft design." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47601.
Повний текст джерелаRiviello, Luca. "Rotorcraft trim by a neural model-predictive auto-pilot." Thesis, Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-04142005-203616/unrestricted/riviello%5Fluca%5F200505%5Fmast.pdf.
Повний текст джерелаBottasso, Carlo, Committee Chair ; Hodges, Dewey, Committee Member ; Bauchau, Olivier, Committee Member. Includes bibliographical references.
"Development of an autonomous miniature helicopter: dynamics analysis, autopilot design and state estimation." 2009. http://library.cuhk.edu.hk/record=b5894129.
Повний текст джерелаThesis (M.Phil.)--Chinese University of Hong Kong, 2009.
Includes bibliographical references (leaves 168-176).
Abstract also in Chinese.
Chapter 1 --- Introduction --- p.18
Chapter 1.1 --- Motivation and Problem Statement --- p.18
Chapter 1.2 --- Literature Review --- p.19
Chapter 1.2.1 --- Avionics Design --- p.19
Chapter 1.2.2 --- Controller Design --- p.21
Chapter 1.2.3 --- Dynamics Analysis --- p.23
Chapter 1.2.4 --- State Estimation for GNSS Outage --- p.24
Chapter 1.3 --- Outline --- p.25
Chapter 2 --- Actuation Dynamics --- p.26
Chapter 2.1 --- Mcchanism Of The Rotor --- p.27
Chapter 2.2 --- Mcchanism Of Swashplate And Rotor --- p.28
Chapter 2.3 --- Numerical Analysis Of Cyclic Pitch Angle --- p.31
Chapter 2.4 --- Helicopter Dynamics --- p.33
Chapter 2.4.1 --- Aerodynamic Forces And Moments --- p.35
Chapter 2.4.2 --- Aerodynamic Drag --- p.36
Chapter 2.4.3 --- Incremental Lift --- p.36
Chapter 2.4.4 --- Tail Rotor Thrust And Moment --- p.36
Chapter 2.4.5 --- Deadweight And Moment --- p.37
Chapter 2.5 --- The Conventional Inadequacy Of Adding A 90° Phase-Lag --- p.38
Chapter 2.6 --- The Gyroscopic Effect In Helicopter Dynamics --- p.39
Chapter 2.6.1 --- How Precession Works --- p.43
Chapter 2.6.2 --- The Analytical Form --- p.45
Chapter 2.6.3 --- Numerical Analysis Of The Gyroscopic Effect --- p.48
Chapter 3 --- State Estimation For GNSS Outage --- p.52
Chapter 3.1 --- GNSS Error And UAV Failure --- p.52
Chapter 3.2 --- "Kalman Filter, And The Extended Kalman Filter" --- p.53
Chapter 3.3 --- Unscented Kalman Filter --- p.54
Chapter 3.4 --- Process And Measurement Model --- p.55
Chapter 3.4.1 --- The IMU Driven Model And Sensor Error --- p.57
Chapter 3.5 --- Modifications To The Model And UKF Algorithm --- p.62
Chapter 3.5.1 --- Acceleration White Noise Bias (AWNB) --- p.62
Chapter 3.5.2 --- Acceleration Scale (AS) --- p.64
Chapter 3.5.3 --- Prioritized Propagation Of States (PPS) --- p.64
Chapter 3.5.4 --- Performance Of The Proposed Enhancements --- p.66
Chapter 3.5.5 --- Tripled Percentage Reduction Of Position RMSE When Using PPS With AWNB --- p.73
Chapter 4 --- Autopilot For Attitude Stabilization --- p.84
Chapter 4.1 --- Oil Test Bondi --- p.85
Chapter 4.2 --- On Unconstrained Flight --- p.88
Chapter 4.2.1 --- Tracking Reference Problem --- p.88
Chapter 4.2.2 --- An Alternative To PID Attitude Control --- p.91
Chapter 4.2.3 --- The Proposed Hierarchical PD Controller --- p.91
Chapter 4.2.4 --- Stability Analysis --- p.92
Chapter 4.2.5 --- Hierarchy Of The Varying Tracking Reference --- p.95
Chapter 4.2.6 --- Asymptotical Stability And Robustness --- p.99
Chapter 4.2.7 --- Experiment and Performance Of The Proposed Controller --- p.101
Chapter 5 --- Avionics And Test Bench Design --- p.105
Chapter 5.1 --- Avionics Design --- p.105
Chapter 5.1.1 --- Design Essentials --- p.107
Chapter 5.1.2 --- Synchronization Of Commands --- p.107
Chapter 5.1.3 --- Normalization Of Servomechanism Commands --- p.110
Chapter 5.2 --- Test Bench Design --- p.110
Chapter 5.2.1 --- The Idea --- p.111
Chapter 5.2.2 --- Concern --- p.111
Chapter 5.2.3 --- Test Bench Design Options --- p.112
Chapter 5.2.4 --- Building The Test Bench --- p.113
Chapter 5.2.5 --- Disturbance In IMU Data --- p.113
Chapter 5.2.6 --- The Solution To IMU Saturation --- p.115
Chapter 6 --- Conclusion --- p.118
Chapter 6.1 --- Actuation Dynamics --- p.118
Chapter 6.2 --- State Estimation for GNSS Outage --- p.119
Chapter 6.3 --- Hierarchical PD Controller --- p.121
Chapter A --- Appendix - Derivation From Recursive Least Square Estimation To Kalman Filter --- p.122
Chapter A.1 --- Recursive Least Square --- p.122
Chapter A.1.1 --- Alternate Estimator form for RLS --- p.134
Chapter A.1.2 --- Propagation of States and Covariance --- p.137
Chapter A.1.3 --- Kalman Filter --- p.139
Chapter B --- Appendix - Actuation by Gyroscopic Effect --- p.144
Chapter B.1 --- Expression of The Induced Moment Due to Gyroscopic Effect In The Total External Moment --- p.150
Chapter B.2 --- An Illustrated Example --- p.153
Chapter B.3 --- Another Derivation By Using A Different Orientation Definition --- p.156
Chapter B.4 --- Dimensions of the helicopter for experiments --- p.166
Bibliography --- p.167
Vijaya, Kumar M. "System Identification And Control Of Helicopter Using Neural Networks." Thesis, 2010. http://etd.iisc.ernet.in/handle/2005/1977.
Повний текст джерелаLee, Chin-Lung, and 李金龍. "DSP-Based Implementation and Dynamic Simulation Of Helicopter Shipboard Launch and Recovery System." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/19244860211629667808.
Повний текст джерела國立成功大學
航空太空工程學系碩博士班
93
From 1970’s, the development of Integrated Circuit (IC) has grown into more important in hardware circuit, because of its stable capability. Without a doubt, the reasons are its smallness, preciseness, high speed, and cheapness. Due to these advantages, we use DSP chip which is manufactured by Texas Instrument to implement this dynamic simulation system in this thesis. The complicated helicopter control loops are simulated by MATLAB & Simulink, translated to C code by real-time workshop (RTW), and finally downloaded to DSP .What we have expect is making the helicopter auto-pilot system lighter and smaller through this research. The contribution in this thesis is combination of system design on a loop : helicopter nonlinear model, LMI flight controller, ship motion, and helicopter shipboard operational environment. We utilize DSP chip for controller of this system to implement the designing of hardware-in-the-loop.
Lai, Gilbert Ming Yeung. "Modelling and Control of Small-Scale Helicopter on a Test Platform." Thesis, 2008. http://hdl.handle.net/10012/3761.
Повний текст джерела盧柏諺. "A System Dynamics Approach to Analyze Helicopter Maintenance Policies – The Case of Army Aviation." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/66401316867830999839.
Повний текст джерела國防大學
資源管理及決策研究所
105
The principle of our military strategy follows the concept of “Strong Defense Posture, Effective Deterrence” and strengthens the capability of air-ground operations, Special Forces, logistic support, etc. Since the Army Aviation and Special Forces Command’s helicopters have high mobility and can work with the air-ground operations; therefore, it could implement a variety of tasks. As a result, the Ministry of National Defense uses the helicopter troops as a part of restructuring of the armed forces. This research focus on the type of Army Aviation helicopters, as this type of helicopters has been serving for more than twenty years accumulating operation hours. The Army Aviation units are facing the problems of spare parts shortage and delivery delay. Consequently, the spare parts inventory is hard to meet the maintenance requirement, which let the aircraft be grounded or even be put into storage. We apply system dynamics to find out the cause-effect relation of critical variables and build a system dynamic analysis model. As a result, this model can be used to simulate different policies, and see the differences of the availability, the number of storage, the spare parts demand and supply, the man-hour demand and the delay time of aircraft removal from storage. The policies, include budget satisfaction rate, safety stock, one for one exchange rate, domestic repair ratio, and storage period. Relevant policy recommendations will also be discussed in this paper.
Matlala, Puseletso. "Design of a DDP controller for autonomous autorotative landing of RW UAV following engine failure." Thesis, 2016. http://hdl.handle.net/10539/23516.
Повний текст джерелаA Rotary Wing Unmanned Aerial Vehicle (RW UAV) as a platform and its payload consisting of sophisticated sensors would be costly items. Hence, a RW UAV in the 500 kg class designed to fulfil a number of missions would represent a considerable capital outlay for any customer. Therefore, in the event of an engine failure, a means should be provided to get the craft safely back on the ground without incurring damage or causing danger to the surrounding area. The aim of the study was to design a controller for autorotative landing of a RW UAV in the event of engine failure. In order to design a controller for autorotative landing, an acceleration model was used obtained from a study by Stanford University. FLTSIM helicopter flight simulation package yielded necessary RW UAV response data for the autorotation regimes. The response data was utilized in identifying the unknown parameters in the acceleration model. A Differential Dynamic Programming (DDP) control algorithm was designed to compute the main and tail rotor collective pitch and the longitudinal and lateral cyclic pitch control inputs to safely land the craft. The results obtained were compared to the FLTSIM flight simulation response data. It was noted that the mathematical model could not accurately model the pitch dynamics. The main rotor dynamics were modelled satisfactorily and which are important in autorotation because without power from the engine, the energy in main rotor is critical in a successful execution of an autorotative landing. Stanford University designed a controller for RC helicopter, XCell Tempest, which was deemed successful. However, the DDP controller was designed for autonomous autorotative landing of RW UAV weighing 560 kg, following engine failure. The DDP controller has the ability to control the RW UAV in an autorotation landing but the study should be taken further to improve certain aspects such as the pitch dynamics and which can possibly be achieved through online parameter estimation.
MT 2017
Tsai, Jiang-Min, and 蔡健民. "A Study of Rotor Unsteady Wake and Blade Dynamics Coupled System in Helicopter Forward Flight." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/76030797394846166730.
Повний текст джерела淡江大學
機械工程研究所
83
The induced wake has a great effect on the stability of a helicopter rotor blades in hover and forward hlight. The research work in this paper is to study the interactions among induced wake and rotor blades. This paper contains three parts:(1) the stability of induced wake and its mode shapes analysis. (2) the coupled system analysis of induced wake and rigid blades. (3) the coupled system analysis of induced wake and elastic blades. The Peters' Generalized Dynamic Inflow Theory with its accuracy and excellent characteristic in coupling is chosen as induced wakde theory. The merit of aeroelastic system coupled with rigid blades and elastic blades lies in it's a three-dimensional model and can be ulitized to predict the stability of a helicopter in different foward flight conditions. This aeroelastic system is etablished in a non-rotating system with which it containts periodic coefficients; thus, Floquet Theory is chosen to perform an eigen-analysis. The results of this paper provide us an eigen-analysis among induced wake coupled with rigid blades and with elastic blades in aeroelastic system. In accordance with the results of this eigen-analysis, we realize that induced wake on rigid and elastic blades flapping damper somehow has an effect in hover and forward flight; especially, the effect in forward flight is much stronger. Above all, the research work in this paper can help to realize a helicopter flight conditions and also to motivate its futher research and design.
HSU, WEN-CHI, and 許文琦. "The Study on Helicopter Maintenance Model in Naval Anti-Submarine Aviation Wing: the Perspective of System Dynamics." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/232a88.
Повний текст джерела國防大學
資源管理及決策研究所
106
Along with the advances in technology and changing in the form of war, the reformation of the R.O.C. Armed Forces should focus on keeping cultivating talents, establishing asymmetric warfare capabilities, and innovating military theories. For the perspective of national security and military defense, safeguarding the security of sea areas is an important issue for Taiwan, a country which is surrounded by sea. The anti-submarine helicopters of our Naval Anti-Submarine Aviation Wing have become an important force in naval anti-submarine operations due to their high mobility and strong monitoring capability. Maintaining the equipment to make helicopters successfully carry out anti-submarine missions has also become an issue that is worthy of attention and discussion. In this study, we use naval anti-submarine helicopters as research object, apply system dynamics to find out the key variables that affect the helicopter maintenance mode and build a system dynamics model. We use this model to analyze and simulate in different policies, and explore the impact of logistic maintenance policy adjustments on the helicopter availability and maintenance costs. Relevant policy recommendations will also be discussed in this paper.
MA, JO-YUN, and 馬若筠. "A Study on the Maintenance and Supply Policy of Attack Helicopter in Army Aviation with System Dynamics." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/95z9jv.
Повний текст джерела國防大學
資源管理及決策研究所
107
This study takes a certain type of attack helicopter in Army Aviation as the research object and uses system dynamics to explore the key factors affecting the helicopter's availability of maintenance and supply policy. This study builds a dynamic analysis model and divides the model into two parts: one is a maintenance and supply policy analysis model for peacetime; the other is a combat simulation model assuming regional conflict in 2035 and taking the available attack helicopters from peacetime model as input. There are several factors taken into consideration, such as annual task hours, spare parts inventory with safety level, the budget satisfaction rate of military procurement and pre-operation time. All these factors have effects on helicopter availability and cost-effectiveness in peacetime. The wartime simulation model takes the helicopter availability from peacetime model as input, and analyze the combat effectiveness (attrition and killed rate) for both sides with Lanchester’s Law in anti-landing operation. This study builds a system dynamics model combining peacetime and wartime considerations, which could be used as a reference for making the regulation of maintenance and supply policy.
Lin, Fang-Jin, and 林昉瑾. "The Coupling Design and Analysis of Chord Length and Twist angle of Helicopter Rotor Blade in Unsteady Wake Dynamic System." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/72078042661563400276.
Повний текст джерела淡江大學
航空太空工程學系
87
Optimum design of two different design variables, chord length and twist angle, through an unsteady aerodynamic system will be considered in this study. Besides, this paper also discuss the coupling effect between chord length and twist angle, and apply wake dynamics, areodynamics and optimality criterion theory to obtain the optimum configuration of rotor blades. The purpose of this study is to obtain a helicopter blades' chord length and twist angle which to minimize the power output and also maintain the lift force in a misson. Because design variable doubles and couples so that the problem becomes complicated, an improve move limit with Bezier curve technique will be implemented in optimal program to overcome these effect. The BELL UH-1H helicopter rotor blades will be redesign by optimum design program exactly and steadily. The result of new design rotor blade will compare with the original rectangular rotor blade in numerical examples.