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Tse, Kim Fung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 103-109). / Abstracts in English and Chinese. / Abstract --- p.i / List of Figure --- p.iii / List of Table --- p.vi / Chapter Chapter 1 : --- Introduction --- p.1 / Chapter 1.1 --- Motivation --- p.1 / Chapter 1.2 --- Background information --- p.2 / Chapter 1.2.1 --- Similar researches on testbed construction --- p.2 / Chapter 1.2.2 --- Formation control theories --- p.2 / Chapter 1.2.3 --- Robot control architectures --- p.3 / Chapter 1.3 --- Basic design of our testbed --- p.4 / Chapter 1.4 --- The organization of this thesis --- p.6 / Chapter Chapter 2 : --- Literature Survey --- p.7 / Chapter 2.1 --- Similar researches on testbed construction --- p.7 / Chapter 2.2 --- Sensors for Distance Detection --- p.10 / Chapter 2.2.1 --- IR Sensor --- p.10 / Chapter 2.2.1 --- Ultrasonic Sensor --- p.11 / Chapter 2.3 --- Formation control theories --- p.11 / Chapter 2.3.1 --- Behavior-based approach --- p.11 / Chapter 2.3.2 --- Leader-follower approach --- p.13 / Chapter 2.3.3 --- Virtual Structure approach --- p.13 / Chapter 2.4 --- Robot control architectures --- p.14 / Chapter 2.4.1 --- Centralized robot controlling system --- p.14 / Chapter 2.4.2 --- Decentralized robot controlling system --- p.15 / Chapter 2.5 --- Summary --- p.16 / Chapter Chapter 3 : --- Wheeled Robot Design --- p.18 / Chapter 3.1 --- Layer Concept in Robot Construction --- p.19 / Chapter 3.1.1 --- Processing layer --- p.20 / Chapter 3.1.2 --- Sensing layer --- p.22 / Chapter 3.1.3 --- Actuating layer (Wheeled Robot) --- p.24 / Chapter 3.2 --- Control Station Setup --- p.27 / Chapter 3.3 --- Sensor performance --- p.31 / Chapter 3.3.1 --- Distance Detection --- p.31 / Chapter 3.3.2 --- Direction Detection --- p.34 / Chapter 3.4 --- "Experiments, results and discussions" --- p.42 / Chapter 3.4.1 --- Experiment 1 - Experiment on MICA performance --- p.42 / Chapter 3.4.2 --- Experiment 2 - Distance maintaining --- p.43 / Chapter 3.4.3 --- Experiment 3 - Robot tracking --- p.45 / Chapter 3.5 --- Summary --- p.47 / Chapter Chapter 4 : --- Levitated Robot Design --- p.49 / Chapter 4.1 --- Possible methods to lift the robots --- p.49 / Chapter 4.2 --- Air table for robot lifting --- p.50 / Chapter 4.2.1 --- Table with air pump --- p.51 / Chapter 4.2.2 --- Table with air compressor --- p.54 / Chapter 4.2.3 --- Comparisons and experiments on the designs --- p.56 / Chapter 4.3 --- New actuating layer for the levitated robot --- p.56 / Chapter 4.3.1 --- Possible actuators for robot to move on air table --- p.57 / Chapter 4.3.2 --- Actuator selection --- p.62 / Chapter 4.4 --- "Experiments, results and discussions" --- p.65 / Chapter 4.4.1 --- Experiment 1 - Testing the performance of actuators --- p.66 / Chapter 4.4.2 --- Experiment 2 - Movement determination --- p.70 / Chapter 4.4.3 --- Experiment 3 - Maintaining position on air table --- p.74 / Chapter 4.5 --- Summary --- p.75 / Chapter Chapter 5 : --- Improvement of Position Detection --- p.77 / Chapter 5.1 --- Direction detection --- p.78 / Chapter 5.1.1 --- One reading approach --- p.79 / Chapter 5.1.2 --- Three readings approach --- p.79 / Chapter 5.1.3 --- Effective readings approach --- p.80 / Chapter 5.1.4 --- Imaginary sensor approach --- p.80 / Chapter 5.2 --- Distance Detection --- p.87 / Chapter 5.3 --- Experimental Results --- p.89 / Chapter 5.4 --- Summary --- p.92 / Chapter Chapter 6 : --- Conclusions and Future work --- p.93 / Appendix --- p.97 / Reference --- p.103

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Thesis (M.S. in Engineering Science (Computer Systems))--Naval Postgraduate School, December 1990. / Thesis Advisor(s): Cotton, Mitchell L. Second Reader: Lee, Chin-Hwa. "December 1990." Description based on title screen as viewed on March 30, 2010. DTIC Descriptor(s): Artificial Satellites, Computer Communications, Students, Theses, Paper, Vehicles, Learning, Circuit Testers, Naval Equipment, Requirements, Control, Reliability Author(s) subject terms: Satellite Communications, Satellite Microprocessors. Includes bibliographical references (p. 91-93). Also available in print.

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The thesis deals with the design and implementation of an Adaptive Flight Control technique for Unmanned Aerial Vehicles (UAVs). The application of UAVs has been increasing exponentially in the last decade both in Military and Civilian fronts. These UAVs fly at very low speeds and Reynolds numbers, have nonlinear coupling, and tend to exhibit time varying characteristics. In addition, due to the variety of missions, they fly in uncertain environments exposing themselves to unpredictable external disturbances. The successful completion of the UAV missions is largely dependent on the accuracy of the control provided by the flight controllers. Thus there is a necessity for accurate and robust flight controllers. These controllers should be able to adapt to the changes in the dynamics due to internal and external changes. From the available literature, it is known that, one of the better suited adaptive controllers is the model based controller. The design and implementation of model based adaptive controller is discussed in the thesis. A critical issue in the design and application of model based control is the online identification of the UAV dynamics from the available sensors using the onboard processing capability. For this, proper instrumentation in terms of sensors and avionics for two platforms developed at UNSW@ADFA is discussed. Using the flight data from the remotely flown platforms, state space identification and fuzzy identification are developed to mimic the UAV dynamics. Real time validations using Hardware in Loop (HIL) simulations show that both the methods are feasible for control. A finer comparison showed that the accuracy of identification using fuzzy systems is better than the state space technique. The flight tests with real time online identification confirmed the feasibility of fuzzy identification for intelligent control. Hence two adaptive controllers based on the fuzzy identification are developed. The first adaptive controller is a hybrid indirect adaptive controller that utilises the model sensitivity in addition to output error for adaptation. The feedback of the model sensitivity function to adapt the parameters of the controller is shown to have beneficial effects, both in terms of convergence and accuracy. HIL simulations applied to the control of roll stabilised pitch autopilot for a typical UAV demonstrate the improvements compared to the direct adaptive controller. Next a novel fuzzy model based inversion controller is presented. The analytical approximate inversion proposed in this thesis does not increase the computational effort. The comparisons of this controller with other controller for a benchmark problem are presented using numerical simulations. The results bring out the superiority of this technique over other techniques. The extension of the analytical inversion based controller for multiple input multiple output problem is presented for the design of roll stabilised pitch autopilot for a UAV. The results of the HIL simulations are discussed for a typical UAV. Finally, flight test results for angle of attack control of one of the UAV platforms at UNSW@ADFA are presented. The flight test results show that the adaptive controller is capable of controlling the UAV suitably in a real environment, demonstrating its robustness characteristics.

Recently, simulation has became the most effective way for analyzing and perfecting the performance of telecommunication networks. It has proven itself as the best method in the realm of education, where the hardware capabilities for practical training are often limited. A simulated network enables students to practice hands-on network programming and to understand, in a practical way, how a data communication network operates and how protocols work.Metanet is an environment that enables the programmer to write networking applications and to test them as if using an IP network with the hosts connected through Ethernet. The whole software is a multi-process application that makes use of just the resources offered by a single machine. It runs on a UNIX system and emulates hosts that also communicate through an emulated network using TCP/IP. Each layer of the hosts' operating system is designed as a separate process that will communicate with the adjacent layers using socket pairs or UDP connections. The application layer has multi-processing capability. / Department of Computer Science

Software emulation of local area and wide area networks provides an alternative method for the design of such networks and for analyzing their performance. Emulation of bridges and routers that link networks together may provide valuable information regarding network congestion, network storms and the like before putting expensive hardware into place. Such an emulation also enables students taking a networking course to develop their own client-server applications and to visualize the basic functioning of the UDP/IP and RIP protocols.This thesis builds on the emulated local area network, Metanet, created by a previous graduate student. It adds the capability of attaching routers and bridges to multiple local and non-local emulated networks so that data may be transferred between two hosts on different segments of the same LAN (via an emulated bridge) or two different networks altogether (via an emulated router). The machines running the Metanet software should support UNIX which has Berkeley's Socket interface as emulated networks on different physical machines utilize this interface for communicating. A comparison of the new networking capabilities of Metanet and other experimental systems like XINU and MINIX is researched. / Department of Computer Science

Thesis (Ph. D.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 140-155). / Also available by subscription via World Wide Web / xiii, 155 leaves, bound ill. 29 cm