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Lau, Tak Kit. / Thesis (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

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Thesis (Ph.D.) - University of Glasgow, 2001. / Ph.D. thesis submitted to the Department of Aerospace Engineering, University of Glasgow, 2001. Includes bibliographical references. Print version also available.

BRANCH OF AERONAUTICAL ENGINEERING UNIVERSITY OF THE WITWATERSRAND / An experimental investigation was carried out on a half scale model of a helicopter COmbined Infra-Red Suppression and Tail rotor Elimination (CIRSTEL) system to characterise its performance in terms of power consumption, thrust, pressure drops and temperature reduction. The model consists of a Circulation Control Tail Boom and Thruster (CCTB&T) with the hot engine gasses ducted into the tail boom where they are mixed with ambiant air supplied by a fan situated in the body of the helicopter. The CCTB&T replaces the conventional tail rotor on a helicopter and supplies the torque to counter-act the torque applied to the main rotor. The model was tested using both hot and cold air to simulate the flow of hot engine gasses. The performance is defined in terms of thrust, power, and mass flow coefffcients which were found to be constant for the configuration tested. It was shown that the power requirements of the fan are significantly reduced by introducing the hot engine gasses into the tail Boom. The temperature of the hot engine gasses is also reduced from 450°C to approximately 200°C The surface temperature of the model was found to be less than 55'C of the configuration.

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